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General CNC Chat => Show"N"Tell ( Your Machines) => Topic started by: Perfo on July 13, 2008, 12:19:42 AM

Title: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 13, 2008, 12:19:42 AM
http://www.chesteruk.net/store/626_turret_mill.htm Sorry I'm not sure how to post the picture yet.

I'm hoping to CNC this mill and have already started to get a few bits and pieces together which is probably the wrong way to go about it as I won’t profess to know much about the whole conversion business.

Parts list so far is:-
CNC4PC  Bi directional buffered break out boards X 2
CNC4PC  Charge pump board
Motion control products (MCP)  MSD542 micro stepping driver X 3
MCP  34 frame (86BYG450B-011) steppers 3 Nm X  2 for X and Y Axis
MCP  23 frame (FL57STH)  Stepper motor  X 1 for Z axis
Power supply supplied by MCP for the above steppers and drivers.

I started building the box of bits as I had in mind to build a Router but when this Mill came up as a damaged unit in an auction I couldn’t resist and thus my project has now changed with the idea that once I get a CNC’d Miller it will make it a lot easier to make the router table.  In the same auction I also got a Chester Craftsman lathe which I may CNC later depending on my success with the mill.
That’s as far as I’ve got.

What I need to do now is:-

1, Build a base with casters on to actually get the lathe and miller in to my work shop    as I can’t lift the things once inside.

2, Ask some learned fellows a few questions to get me started.

One problem I’ve got is I can’t get Mach 3 to run on my Vista machine ( the driver test fails) but I’ll go through all the set up install steps again as I’ve probably missed something (I’ve installed the memory override dll)

With reference to number two above:-
What sort of drive ratio should I have on the X and Y axis ? I was thinking of using the steppers in 400 pulse per rev mode and each rev (using the standard ACME screws) gives me 3 mm travel.
As the longitudinal travel is 365 mm and I guess it would be nice to be able to travel this distance in high speed non cutting mode (Jog mode ?) in about 30 seconds this would mean 120 ish revs per traverse and 48 K pulses or 1.6 Khz (please tell me If I’m talking utter rubbish here) . If my calcs are anywhere near correct then I could afford to have a 10:1 reduction ratio on the stepper as it should be about to run at 16 Khz no problem (shouldn’t it ?).  Cross travel is half the distance but the same gearing would be ok. The thing that worries me is looking at some pics I’ve found on the net, some folks seem to have coupled the steppers direct or at least through a 1:1 ration pulley system. Surely this would give you an unusable traverse max speed and need you to get bigger motors….hmmmmm…
Last question. I’ve seen a Mill doing thread cutting under control of Mach 3 on you tube and it looks very impressive but how does the Z axis the cutter and the rotating work piece stay in sync ?? I can see how the Cutter and Z axis does but the spindle is free to rotate, Isn’t it ?
Anyway thanks in anticipation for any help or suggestions anyone has.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 13, 2008, 07:24:35 AM
Would recommend you go higher than half stepping, probably best 10x. You should manage to go 1:1 with these motors if the mill had ballscrews, not sure with the acme's thouggh. Wouldnt go as high as 10:1 as I dont think your motors will turn fast enough but you never know.
 The thread cutting thing depends on what you have seen, if its thread milling then the spindle speed is not important, reason is the cutter is spinning round but the X, Y and Z moving in sync with one another is what controls the dia and pitch. Rigid tapping is a whole different ball game, for that youneed prcise spindle control, you can also use a floating holder and do semi rigid tapping but you will still need spindle control (Speed,Fwd and Reverse)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: wantcnc on July 13, 2008, 05:16:07 PM
I converted a Warco VMC which is the same machine as the 626
I used the Motioncontrol MSD542 with the 86BYG stepper on all axis
Which includes the Knee. The reason for this was that the play on the rack and pinion on the quill is rather large (I tried),  where as the weight of the knee pushes all the play to one side.

The ratio used is 3:1 as this works well with the lead screw 3mm pitch
The Z runs on a 6:1 due to the weight
It all runs happily at 600mm/minute which I regard as about the limit for soft cast-iron ways.
The screws are frequently adjusted and lots of lube is required on them

I “customized” three large transformers to give 50V DC at the drives

The machine runs at least 2 days a week production work 8 hours long, and not a beat is missed.

I have been able to fit all the motors in such a way that the machine is not bigger…
I turned around the X axis screw and then fitted the X motor “under” the table
This is done so I can fix a scale on the other side of the knee.
The Y axis also lives “under” the knee, and finally the Z axis. I removed the hand crank
and fitted the toothed wheel on the Z screw the stepper sits on a plate inside the Knee
which is fixed in place of the crank bearing plate. In this way the envelope is not larger due to the stepper motors, which you often see in conversions
when you remove the screws to install wheels, check the bearings and how they are fitted
the Chinese have a thing against finishing…..

I would like to have ball screws, and in time when the machine has earned some of its keep I will fit them. For now I am a happy with the machine and the conversion
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 13, 2008, 09:16:55 PM
Thanks for your answers. It’s good to see someone has already done it on the same machine and with the same steppers and drives.
Wantcnc did you try to direct couple these steppers?  When you say 10:1 or 3:1 I’m assuming you mean 3 turns of the stepper for one turn of the lead screw. How did you mount the steppers ? Was it with toothed belts ?
Sorry I may be being a little slow but I couldn’t quite follow.

I turned around the X axis screw and then fitted the X motor “under” the table
This is done so I can fix a scale on the other side of the knee.

The X axis screw has a bigger over hang on the right hand side due to it being possible to put a powered cross feed on it. Did you mean reverse this so the extra was on the left ?
Any chance you would have a couple of pics I could see to help me visualise the set up?
You must be happy with the outcome and the machines performance so that’s given me a bit more confidence in surging forward. Motion control products have a few steppers in their clearance section so I may need to get on of these for the Z axis as my Z axis stepper is much smaller than the others. I had thought of putting the Z on the hand wheel purely due to the weight of the knee but I take your point about the play and thus will probably follow your example. I assume you are in the UK somewhere? Anywhere near Bangor N Wales ?

Thanks again Gents. I’m a member of other forums (not CNC related) and have spent a lot of time trying to help others and it’s real nice now I’m a newbie to find a forum where experienced people are willing to help
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 14, 2008, 12:42:13 AM
I tried to find the thread milling video without much luck. Here's one very similar
http://youtube.com/watch?v=Dlz0EUq6k9M
I can see this fellow has a shaft encoder. Even with the encoder I'm still amazed it gets the start for the thread spot on with every cut. I'm used to lathes where there is a physical connection between the feed and the chuck so it has to line up. I still think this sort of thread cutting would be better on a lathe but if you've got a CNC'd miller then I suppose you are going to use it for everything you can think of.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 14, 2008, 02:34:33 AM
That guy is basically doing Lathe threading but using his mill, what you need for the is a single pulse per rotation from the spindle so that Mach can calc when to start Z movement and also what the spindle speed is.
 Thread milling is different and probably better suited to a mill, heres a vid of thread milling.
Hood

http://www.youtube.com/watch?v=JA_osyWIEFY
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 14, 2008, 09:35:01 PM
Oh yes I see the difference. Nice bit of thread milling there.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: wantcnc on July 15, 2008, 03:08:05 AM
work is getting in the way at the moment, will try to post a few pics later this week

motor 3 turns shaft 1 turn....
never tried it 1:1 I would be supriced if it would work, on ball screws it may work...but then that is  ££££
X axis rotate was done since I started to fit the motor on the right side, and then realized I needed that for the scale later on
since the shaft is bigger on the right side, I had no choice but to rotate the screw.
I took of the hand wheels....no point if you have a jog wheel and it only adds to the inertia
I still need to cut of the excess shaft.


I'm in NW London :(

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 15, 2008, 09:04:53 PM
A pic paints a thousand words as they say. I'd be interested in where you got your gearing from IE did you use toothed belts and wheels ? I'm thinking there's no point reinventing the wheel here and if you are happy with your system and have proven it to work well then that's just where I want to end up :)  Work interferes with all the best past times doesn't it ? I've had one day of in the last 30 days and that is really slowing the progress on my mill conversion. I get down to Hertfordshire every now and then as I come from Stevenage and have family there so not too far from N London.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 20, 2008, 07:36:08 AM
has anyone got any suggestions as to a good gearing system to get the 3:1 mentioned above ? I'm thinking of timing belts and pulleys, Where would I get suitable ones in the UK ?
Thanks
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 20, 2008, 07:39:35 AM
Timing belts and timing pulleys are the way to go, backlash free and reasonably quiet. I get mine from BSL or Brammer as they are now known but any bearing supply place would be able to get them for you if they dont have them in stock.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 20, 2008, 10:54:10 AM
Thanks. I'll give them a google.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: wantcnc on July 20, 2008, 03:59:52 PM
as promissed some pictures

X and Y are on the proper brackets, Z is still on a lash-up one day I'll get the time to finish that one
for now it works....

I got my belt bits from RS, not the cheapest but it got me going in a hurry

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 21, 2008, 02:55:53 PM
Some good informative pics there my friend thanks. Are they 12mm belts ? Have you thought about putting a solenoid on the oiler ? just something that came to me whilst looking at the machine it could be pulsed every programe run by mach and again at the end of a run.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 22, 2008, 01:56:25 PM
The 600mm per minute max speed will traverse the 365mm table travel in around 36 seconds which I suppose is slightly on the slow side but still quick enough for me I can always upgrade to bigger steppers and ball screws if I found the speed a problem. Y axis is no problem of course at this speed having a much shorter travel. I was thinking of maybe going for a 10:1 on the Z axis as I get nervous when I feel the weight of the knee and table assembly. Do you think a 10:1 would make the Z too slow? I know the total travel of the Z is 360ish mm but in reality wouldn’t you only be using up to 100mm of that travel and for most applications even less. Am I right in that assumption? I’ve got lots of time to think about these things while I wait the long three weeks for my smooth stepper to appear from over the pond.
Thanks again chaps.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 22, 2008, 02:13:29 PM
Hood. Any clues as to which belts and pulleys are suitable ? I can't find any timing belts on the UK brammer site. I've found a few at
http://www.bearingboys.co.UK/Timing_Pulleys-1042-c
But there are hundreds with different codes on that don't mean much to me. Some are pretty hefty in price as well IE over £300. What width of belt is likely to be adequate ? I was thinking 10mm but it's not obvious to me which of the ones on the site are 10mm. Hmmmm
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 22, 2008, 04:24:33 PM
I've had a look on the RS site to. They don't appear to be that overpriced the cheapest I could find was a company called HPC I'll have to give them a ring tomorrow as again whilst their site is a bit easier to navigate than most I'm still not sure what type of pulley and belt I need. WantCNC if you get a few minutes can you remember or have you got to hand which pulleys and belts you used in RS?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 23, 2008, 07:09:59 AM
I think RS will be a lot dearer than your local bearing supplier, Brammers website is crap but they have helpful people at their local depots, well at least I have found that to be the case.
 I have a book at home that gives sizes etc and will look tonight and give you the codes for the ones I put on my Bridgeport (manual conversion one) That would be suitable for yours for sure.
 I just bought some 125mm Dia 14mm pitch 50mm wide for my new mills spindle, inclucding the taper locks I think I was around £50 but again will check tonight and let you know.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 23, 2008, 12:42:07 PM
Wow 50mm wide that’s a chunky belt. I suppose it is the main drive so has to be good for a few horses. Some motor bikes use timing belts as the drive and by eye these are probably only a bit larger than 50 mm and are good for I dunno 60 Hp.
I've found a company called HPC gears on the net and gave them a phone. You give them the ratios, shaft sizes and power of the motors etc and they'll work everything out for you. The fellow got me thinking though he asked what the shaft speed of the Motors was.  I did a quick calc back from 600 mm per minute and came up with 600 RPM as there is a ratio of 3:1 and the lead screw is 3 mm per rev. This started me thinking at 800 pulses per rev this is only 8000 Hz’s. Is this a normal frequency to run these motors at i.e. are there torque problems trying to run them any faster. At 800 steps per mm of travel I have a resolution of 0.00125 mm per step so plenty fine enough for my set up. Should they run faster? Or am I missing something fundamental here?
WantCNC what is the restriction to 600 mm per minute I’m guessing it’s the torque curve and even though 600mm is fine for me I still like to know these things.
Thanks for looking Hood.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 23, 2008, 03:36:43 PM
Yes its got to be a chunky belt, its a BIG AC servo I am putting on the spindle, 163Lb-in Continuus and 490 lb-in peak and dont want any mishaps LOL

Think your calcs are a bit screwed ;)
 200 steps per rev x 10 microstepping (if you are indeed using micro stepping) = 2000 per rev, 3:1 gearing = 6000 thats 3 mm so 1 mm is 2000 steps per unit, 600mm/min at 2000 steps per unit = 600 x 2000 = 1,200,000 per min divide by 60 and thats  20KHz.

Not really sure what steppers will do but will work mine out and that will give you an idea (916 oz in on a Bridgeport Series 1 CNC) 2500mm/min Rapid speed, 5mm pitch screws so thats 500 rpm at the ballscrew, 2.5:1 gearing so thats 1250RPM at the motor. Think my calcs are right LOL

Just away to look see what size belts I got for the first Bridgeport I did.

Hood

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 23, 2008, 03:50:04 PM
Problem, book must be at the workshop after all :( gotta get the desk tidied up so I can find things LOL.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 23, 2008, 04:01:06 PM
hmmm Yep I wasn't counting on micro stepping I thought 800 steps per rev would be good enough as your 20Khz on 2000 steps is correct then div it all by 2.5 gives you 800 steps per rev at 8Khz. I think my calcs and yours are the same except I didn't factor on micro stepping. Does this seem likely?
This is where I come unstuck I'm quite at home with software or electronics etc or even mechanical systems that I've got a bit of experience with (which I haven't at all with a mach3 setup on a proper mill).
As concerns how many steps to use I simply thought what's my target accuracy. I guessed 0.01mm would be a good starting place but not sure if it's realistic. I then thought if 0.01mm is my target then the electronics must have at least this level of resolution so I guessed I'd need at least 100 steps per rev. With my motor and drive combo I think the minimum I can get is 400 steps per rev so I doubled it to 800 steps per rev thinking this gives me a resolution of 0.00125mm I then multiplied or divided this with my mechanical gearing to actually arrive at a final resolution figure which in my case as I have a 3mm pitch lead screw and a 3:1 gearing on the motor I end up with 0.00125 mm travel per step. I’ve got this sneaking feeling I am missing something fundamental here so please don’t give up me just yet. Are there any advantages of micro stepping except a smaller degree of rotation per step? And thus do I need more than 800 steps ?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 23, 2008, 04:16:21 PM
Your bridgeport seems a bit bigger than my 626/vmc which I'm glad about as my steppers are only rated at 305 Oz-in of holding torque (is this the same thing?) so they have a third of your stepper power.
No probs with the book thing whenever you feel like it when you have a minute is good enough for me. I'm still waiting for the base to be released from a fellows locker which I may get back next week. Then I've probably got another week on top of that to wait for my smoothstepper. At least when i get my Base back I can start machining the plates etc for mounting the steppers on.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 23, 2008, 04:21:14 PM
Micro stepping makes for smoother motion, Mariss says 10 micro steps is the ideal and I believe him, he knows his steppers :)
 You seem to be working arse for tit LOL, what you want to do is work from your hardware and that will give you your steps per unit, from that you can work out what kernel speed you would need for a given speed (although if SS its not an issue)
 Ok so stepper at 200 steps per rev, you get Geckos with 10 micro steps so that 2000 steps per rev, 3:1 gearing = 6000 steps per rev of the ballscrew. Ballscrew move 3 mm/rev so thats you back to 2000steps but its per unit now (1 unit = 1mm in your case). With a 2000step per unit I would think you could get 1250mm/min out of a stepper, I get 2500mm/min  with 1000 steps per unit ((200 x 10 x 2.5) / 5) = 1000 steps per unit. Smaller motors can often rotate faster so if you are using smaller steppers you may well get a faster speed.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 24, 2008, 09:57:16 AM
okay cokay then that's how I'll set it up. I do like to know the inns and outs of things but will always opt for the proven tried and tested methods suggested by fellows such as yourself then fiddle and break them later once I know it's all working. :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 24, 2008, 04:21:25 PM
What drives are you getting/have got?

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 24, 2008, 09:37:46 PM
I've got myself some fine 86BYG450B-011 from motion control products 4 phase 4 amp per phase 305 oz/in (2.16 Nm holding torque. I've only got two at the moment but need to find a third as they no longer do these in MCP but have got similar In my simplistic mind I thought I'd try the two I've got and if they work fine then get another but if it struggles on one axis then I'll get a bigger one for that axis.
To with them I've got three MSD542 Microstepping Driver (4.2A Peak)  from the same company.
I must admit though I'm not sure holding torque is directly related to driving torque.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Overloaded on July 24, 2008, 10:26:09 PM
About stepper torque:
    Here is the the general summation of the following topic.
  "As a rule of thumb - the MAXIMUM dynamic torque of a motor will generally be in the order of around 70% of its holding torque."

http://www.machsupport.com/forum/index.php/topic,6466.msg42355.html#msg42355
RC

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 24, 2008, 11:57:23 PM
Thanks. I'm begining to think that maybe my steppers aren't quite big enough. Still it's only a gear change and slowing down the travers so I'll get it going one way or tuther then upgrade in future if need be. Your bridgeport look a bigger beast than mine so maybe it would take 3 times the torque to get it performing properly. I'd be v happy with a performance half of yours ie 1250 mm/m.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 25, 2008, 01:49:55 AM
perfo
 think your steppers should be fine, your mill is quite a bit smaller than the Bridgeport. Another thing  is the Bridgeport has plenty power with the 916 oz/in steppers, I was at one point thinking of reducing the gearing to ge better rapids. Have a new mill I am working on now with AC Servos so not going to bother doing anything to the Bridgeport.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 25, 2008, 11:44:35 AM
That's good to know. I'll have to keep my eyes open for another one then secondhand preferably. What did we do before eBay ? :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 25, 2008, 11:53:10 AM
Just looked at the BSL book, the pitch of the belts I used was 5mm and the belt width was 15mm.
 Not sure where you get your steppers from normally but they are not really that expensive nowadays, certainly mmuch cheaper than when I started out converting my manual Bridgeport 4 or so years ago. ArcEuroTrade sell the same as mine for around £50 and the next size down is about £30 if I remember correctly. Not sure the prices of other places but would think they are about the same.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 25, 2008, 01:27:26 PM
I just had an email back from HPC gears. I told them originally (when I'd gotten the wrong figures) that I had 3Nm motor rotating at 1800 RPM. I gave then the min center sizes and they have done calcs. They say I'll be good for 10mm on the X and Y axis but due tot he 8:1 ration on the Z I'll need 25mm belt or I can go for a 16mm if I use a tensioner pulley with at least 180 degree wrap around. I'm guessing 10mm will handle the torque it's just the lengths needed to get around a 10 then 80 tooth pulley with center bore size of 16mm. You data obviously confirms this if 16mm works OK for you then 10mm will be OK for me. I've asked them for some prices now and the difference between 16mm with tensioner and 25mm without..
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 31, 2008, 03:15:55 PM
The final parts list for 2.16 Nm 1200RPM steppers on each axis is:-

2 X 24ABT5-15 24 TOOTH PITCH 5mm 15mm WIDE PULLEY TO FIT A 10 mm BELT FOR THE X AND Y AXIS
2 X 72ABT5-15 AS ABOVE FOR X AND Y GIVING ME A 3:1 REDUCTION
1 X AT5/455/10 10mm WIDE 455mm LONG BELT FOR X AXIS
1 X AT5/545/10 10mm WIDE 545mm LONG BELT FOR Y AXIS

1 X 10T10-17 10 TOOTH PITCH 10mm 17mm WIDE PULLEY FOR Z AXIS
1 X 80T10-17 80 TOOTH PITCH 10mm 17mm WIDE PULLEY FOR Z AXIS GIVING ME AN 8:1 RATIO
1 X T10/920/12   12mm WIDE PITCH T10 BELT 920mm LONG

It took a while for HPC to reply to me with some figures but the gent was quite helpful. I've now got a bigger problem they’ve quoted me £443 for the above belts and pulleys. That's a figure I just can't afford at the moment I've spoken to BSL and hopefully they are getting back to me tomorrow with a quote but it would have to at least half that figure to be do able. I've got my smoothstepper now and the customs added £16 Vat on top at the border then parcel force added another £8 for their handling costs?? Still it was a bit cheaper than buying the smoothstepper in the UK. I’m a bit gutted at the moment as the £400 + was a complete shocker. It’s my fault of course for not budgeting for it but it puts my project on a firm hold for a bit :( . I’ll look into worm drives or something to see if they work out any cheaper as you can get anti backlash worms and I’m feeling once I’ve got the Mill up and running I can then make some pulleys myself (wishful thinking maybe) . Downside is I won’t be able to use the mill as a conventional one unless I rig up a worm engage/disengage mechanism. Hmmm maybe a car timing pulley could be used I have a couple of them somewhere in the garage.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 31, 2008, 03:26:13 PM
If BSL are much over £100 tell them thats nice, now whats the price with the discount :)
 I have a small HPC book I have had for maybe 15yrs or more and I still get a laugh when I look at their prices, you would think after that many years their prices would be kind of out of date but they are still more expensive 15 yrs on :D

I cant really remember what my pulleys  cost  for that kind of size/pitch but I think around £20, could be wrong though.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 31, 2008, 03:49:38 PM
The 72 tooth ones are £46 plus vat and the 80 tooth t10 ranged from £178 to £203 plus vat depending on if I use a tensioner or not. If BSL come back with £100 or less they will get a new friend. The company I work for has ordered stuff from them before so I've gone through the company connection though I've told them it is private so fingers crossed discounts will be included.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on July 31, 2008, 03:50:12 PM
The HPC moto is "we will never be outpriced"  :-)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 31, 2008, 03:59:45 PM
No way BSL will be under a £100 but no way they should be anywhere HPC prices. What was the price you said RS was?

I can tell you what HPC would say if you told them you could get the pulleys/belts half price somewhere else, they would say yes but not the same quality of our stuff. You would probably find they are from the same batch as the half price suppliers stuff :D

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on July 31, 2008, 04:23:00 PM
Perfo heres the prices of the pulleys/belts I got for the Bridgeport, they are 3yrs out of date but shouldnt have gone up that much, VAT is not included
P30-5M-15MMPB/HTD £5.86 each
P60-5M-15MMPB/HTD £9.94 each
425-5M-15MM               £5.83 each
750-5M-15MM               £9.34 each

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 01, 2008, 02:41:32 PM
That's definitely more like the price I was expecting.
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0184842 this is a link for a 72 tooth T5 HTD pulley £19.64 so less than half the price of HPC at £46.83 though they say theirs (HPC) is a reduced backlash pulley. I'm not sure what the difference is between a HTD and a AT5 or ABT5  but I'm guessing the most common is HTD and these will be fine for my application. BSL are getting back to me on Monday now as they either haven't had time to work out a price or someone forgot. I'm also getting a price from anti friction components which is a local bearing supplier that also deal regularly with my place of work. I'm feeling more optimistic now I may be able to get some pulleys after all.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 01, 2008, 02:46:35 PM
On Re reading the HPC quote it seems to be for pilot bore pulleys as there's no mention of grub screws or keys.
The steppers I'm using have 9.5mm shafts with a flat on so I'm hoping for 9.5 mm bore and grub screw for the 24 tooth and the 10 tooth pulleys. The 72 tooth are going on to a 16mm keyed shaft and the 80 tooth on to an 18mm keyed shaft. I've given all this info to the various companies and stated I can bore out to 9.5 mm if need be but I'm a bit stuck to put a key way in at the moment. That would be a lot of filing I think :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 01, 2008, 03:09:09 PM
It seems HPC have led me up the garden path a bit with what pulleys I need etc. Even RS are quarter of their price the HTD belts are around £5 even for the big Z axis one. I'm feeling that HTD will do me fine and the sales talk of I need this and that whilst may be true they are better they are a lot higher spec than  I need. The downside with RS is they haven't actually got the sizes I'm after they do ones that are close but not the same. IE 9mm or 15mm pulley not 10mm I guess I would have to go for the thicker but don't want to increase drag anymore than necessary. I'll await MR BSL and AFC on Monday and hope they have good news. Hmmm then again it was HPC that told me what I needed I told them the ratios and the RPM/power of the motors and they told me what size pulleys and belts I needed. I think they probably got that bit right though the fellow did sound like he knew his stuff all be-it a tad pricey.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 01, 2008, 03:38:02 PM
I would say the difference between the others and the HPC ones, excepting the cost, is you get a generous helping of bull********* thrown in with HPC :)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 01, 2008, 03:40:28 PM
9 and 15 are standard sizes, 10 and 16 are not. Well thats from anything I have seen.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 01, 2008, 03:43:08 PM
You can opt to go for taper lock pulleys/bushes. Thats what I got for the Beaver mill I am doing, bit more expensive than pilot bore but  way cheaper than HPC :D


Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 01, 2008, 03:49:28 PM
I don't pretend to be any kind of expert on pulleys except that I realize a different number or letter could mean a belt or pulley wont fit.  I'm wondering now then If I should have told BSL and AFC that anything near 10mm would be good enough I basically gave them the spec from HPC thinking these things are fairly standard I hope they don't waste a lot of time trying to match the belt sizes etc exactly. For taper lock I assume you get a standard taper lock adaptor and the pulley fits on it as in the gents pic on this thread. It's another option to think of.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 01, 2008, 03:59:54 PM
Yes taper lock bushes/pulleys come in series, so for one size taper lock there may be 30 different bores you can get. As an example the pulleys I got for the Beaver spindle were both the same
P28-14M-40MM/HTD but I got two different bushes to suit, one for motor and the other for the spindle. Motor one was 2012-24 and Spindle 2012-50. 2012 is the series size and 24 or 50 is the bore size. You wont be going for anything that big so the series number will be different as well.

Hopefully BSL and AFC will just spec you for nearest but they may well try to match as with you giving them part numbers they are probably thinking its from a machine and you need exact replacements. My local BSL is open Saturday mornings so maybe yours will be as well and you could give them a call, if not it will have to be Monday :(

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 01, 2008, 04:03:22 PM
http://www.fptgroup.com/products/taperlockbushes.asp

Thats what Taper Locks are

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 02, 2008, 09:06:02 PM
Splendid on the taper thingys it would save a bit of hassle if I dont get them pre keyed.
I've got all my bits and pieces in a box today. I found an old rack mounted PC case in a skip which is ideal as it has a couple of big fans and an ATX power supply to power the BOB's. The smoothstepper, 2 X BOB's, 3X stepper drives(MSD542's) and the motor PSU all fit in nice and neat in the one box. I'm thinking of connectors now for the leads to the motors. I'm connecting the 8 wired motors in parallel so I'll only need 4 cores to each motor. So I'm thinking of what kind of connectors I can mount in the rear panel of the new box which will be OK at 4.2 amp. The idea being it will make the system neater and if I then mod my lathe which I hope to do once the mill is sorted then I can unplug the Mill from the control box and simply plug in the lathe. I could go for a connector that has enough pins to take all the motors and a few extra for home and limit switches but this means them being pretty close to each other in the plug and seeing the problems people have had on here with cross talk and noise I'm thinking individual plugs with screen cable for each motor and another one for switches.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 03, 2008, 03:38:24 AM
Yes definitely go with single connectors for each motor, I would even go with single connectors for each limit. Rapid is probably about as cheap as you will get in the UK, have a look here for the circular style http://www.rapidonline.com/Cables-Connectors/Connectors-Multipole/Circular-Connectors/Circular-locking-multipole-connectors/66501

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 03, 2008, 07:31:38 PM
They look pretty similar to the ones I got today, mine are domino 5 pin but I'll only be using four. They aren't locking either like the ones in your link but are a pretty good fit and connection. I've gone for 4 plugs and sockets at the moment as you've suggested to keep the limits etc on a separate plug. Next question is what cable to use? I had some instrument cable that has four cores and is screened but my mind played tricks on me as I thought they had about 1mm core but alas it's only about 0.2 mm So not much good for 5 amps. The motor peak current is 4.2 A so I'm expecting anything above about 1 mm would be sufficient and not give me too much volt drop over the 4 to 5 meter run (preferably screened). how important do you think the screening is? The most crucial part of the screening I would have thought is in the step pulses to the driver as any parasitic elements on this line could distort the wave form but these are a good distance from any motors (noise sources) and very short so I'm not expecting problems there.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 03, 2008, 07:38:59 PM
I had thought of using Cat5 cable and doubling up the cores (as it 8 core) This would have made a neat solution as I can get them ready made in different colors from ebuyer pretty cheaply so could put RJ45 type sockets (which I've already got from an old 20 way router box) on the back of my control box and on the enclosure for each of the motors keeping everything neat and tidy and no chances of noise being a problem. The only applications I've seen using POE (power over Ethernet) go up to about 720mA per core so I'd only get 1.5A on a pair of cores which isn't enough.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 03, 2008, 07:41:21 PM
I screen everything, maybe a bit daft but I never get problems with noise. Well thats not strictly true as on the lathe and the mill I am doing most of the control stuff (limits included) are 24v and some of that I dont have  screened. I always screen any 5v stuff and all motor and encoder lines are screened. SY cable is good for the motors and eBay usually has a fair bit in the 1mm and under.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 03, 2008, 10:01:35 PM
hmmm I suppose trailer / Caravan cable would do but it's not screened and not particularly cheap.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 04, 2008, 08:52:07 PM
I'll do a search for SY cable thanks....
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 04, 2008, 10:01:23 PM
Not much on ebay at the moment but it was something I'd forgotten about I'm more used to calling it multiflex or metaflex I think as the sparkies used to call it when I was a mere lad in the apprenticeship. I've got a bit of time yet to ge the cable I'll use anything for now just to get stuff working. I'm still waiting for AFC or BSL to get back to me about the pulleys. I'll harass them again tomorrow. I'm on nights at the moment so sorta run out of enthusiasm by the time I get home and the shops are open.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 04, 2008, 10:03:14 PM
Your limits go straight to a contactor do they ? So it knocks the juice off if they hit?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 05, 2008, 02:05:52 AM
No my limits go to a relay board that I made up, this allows me to use 24V to the limits and just have a short shielded 5v signal wire to the BOB see pic below of the board I made.
Hood
ps thats it just getting tested after soldering so all the link wires would be replaced by switch wires.

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 05, 2008, 08:25:07 PM
Did you mill that PCB or etch it ? I had a bad experience with Ferric Chloride once in my youth making PCB's on a hot sweaty day and ended up with the stuff all over my face..no lasting damage that you can see but was pretty unpleasant for a few years.  Nice to see the ol LED's there multi state LED's would give you red for hit and green for good. The saga continues with the pulleys. I emailed them (BSL) on Saturday to ensure they didn't try and match like for like with HPC but alas it did no good. I phoned them this morn as I hadn't heard anything and they hadn't progressed it at all stating they items didn't look standard. Anyway I explained it all again that as long as I had the ratios and the belts etc roughly the same width IE the system can handle the torque then I could take almost any pulleys. I was on the phone for about 20 minutes explaining I want standard items nothing fancy no matter about flanges or bosses or width of pulley etc etc as long as the 24 tooth and the 72 tooth and the belt matched then it would be ok. I did admit that in my ignorance I had completely misled them by giving them the spec form HPc and asking for a price so it's not really their fault. Anyway you live and learn and have great hopes for tomorrow. I had a good buy on eBay last night got a ER32 R8 collet chuck for £5.75 and a complete collet set up to 20mm for £12 so that should keep me busy for a bit. The gent that had put my lathe and mill base in his locker is in work today/tonight (at long last) so hopefully I can finish drilling and tapping that and it'll be ready for painting and fitting tomorrow.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Chaoticone on August 06, 2008, 12:17:40 AM
Hood etched the PCB for his relay card and did a great job. That Hood is handy as a side pocket.  :D

Brett
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 06, 2008, 06:08:04 AM
Yes as Brett said it was etched, and yes you do have to be careful with that bloody stuff.

Hopefully BSL will get you sorted today.

Great deal on the collets especially :)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 06, 2008, 04:46:35 PM
BSL still haven't responded but AFC have, and their price is £100.21 plus £10 for PnP I don't know if that includes VAT I guess not and don't care much :). I should be getting em on Monday. Problem is they are only pilot bore not keyed etc looking back tot he HPC ones they didn't quote for keyed either though I had told them the shaft sizes and which had keys and which had grub screws. I can bore them out my self no prob but will have to put my thinking head on to figure a way of putting a key in. Still it's do able one way or tuther.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 06, 2008, 06:26:57 PM
I have heard that about some branches of BSL but the one I deal with have always been excellent on service.
 There are a few ways to key, you could grind up a tool and place it in the lathe  and crank back and forward taking a slither off each time. Same with the mill if you chucked up a tool. Another way would be to get a milling cutter the right Dia and plunge down to make a half round slot then file. I have push broaches but unless you know someone that has them its not an option as they are pretty expensive. You could also just put the grub screw into the keyway in the shaft but its not the perfect solution so if you do that make sure its locked in tight.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: cjmerlin on August 07, 2008, 08:54:37 AM
Hi, I did mine in the lathe as Hood explained, Just grind a bit of Hss tool bit exactly the width you need with a slight angle on the end so the chip curls up as you take a cut. I locked the chuck solid using a bit of flatbar mounted on one of the chuck holding bolts and the chuck guard screw on the headstock. Just wind the lathe carriage back and forth taking small cuts. The whole thing took about 30 mins.

Cheers
John
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 07, 2008, 09:02:54 AM
Thanks for that. I was thinking of the mill thing I thought mill a slot then file off the rounded bottoms of the slot. I did think about the scrapie idea but wasn't sure how I'd stop the toll turning in the mill but of course you're idea with the lathe would get round that problem. I think I've got a bit off HSS somewhere I'll have to have a think when the pulleys come. I believe we have got some of those broaches at work but they are at a different site and may not be that happy to send them across for a novice like me to break them :)...I'll try and think of a job to send one of the mech lads over to the other site and just happen to ask him to take these here three pulleys for keying ;). I suppose most on here have a starting point ie they are already proficient tool makers and just want to take their skills to a new level. I on the other hand still look at the lathe or miller with a what's going on here type approach so have a double learning curve..though I suppose having a software/hardware back ground this part of the conversion isn't so daunting where others may be afraid.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 07, 2008, 01:27:55 PM
When(if) I do my lathe conversion is it a reasonably attainable goal to produce the pulleys myself on the mill ? Some of the belts have half round teeth so it could be done on a three axis if the tool is the right diameter. I suppose an automated indexing head (4th axis ) would make it a lot easier and could then do square bottomed teeth as well. I've seen on another forum where people melt there own aluminium and produce blanks in sand moulds. Would that give a good enough quality on the alluminium to then be machined and be good for 1000 RPM?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 07, 2008, 02:23:01 PM
Would prefer to get the proper pulleys myself, also  dont think the pulleys profiles are actually half circles, think they may have some relief on them for leading the belt in. Dont have one here to look at but if I remember tomorrow I will have a look.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 07, 2008, 03:01:01 PM
Don't put yourself to any trouble Mr HOOD it was more of a passing thought than anything I'm seriously considering at the moment. Pulleys come tomorrow with any luck.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 07, 2008, 03:18:52 PM
Thats great, so tomorrow evening you will be making chips?
(http://forums.pcper.com/images/smilies/extras/yllol.gif)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 07, 2008, 04:30:45 PM
Well it is Friday so it would be traditional. :) . Plan for tomorrow is to powder coat my base frames (If I can figure out how to do it) now that I've wrestled them back from the fellow that hide them. Working on eves tomorrow which may hamper my efforts. I have a stumbling block that I can't then get the mill or the lathe on their retrospective stands as they are too heavy. I have a cunning plan that involves borrowing a pallet truck from somewhere, getting the stands and the machines outside then using my tractor to lift them on. Ones on then my new fangled bases make it easy to maneuver them around. If I can do this tomorrow then I'll be in a position to start chipping on Saturday but at present I haven't got the use of a pallet truck. I can borrow one from work for an hour over the weekend may be.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 07, 2008, 04:39:36 PM
Look forward to the the pics ;)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 08, 2008, 03:57:26 AM
Yep I'll have to get some of them sorted. Thanks for the confirmation CJ (john) I may just have a go at it.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: cjmerlin on August 08, 2008, 06:35:26 AM
Hi Perfo, Yep. just make sure that the center of the cutting edge is exactly on the center line or you will get an offset keyway slot and the pulley will never fit the shaft. I made a few cuts and then double checked by offering the shaft to the pulley.

If you do go wrong with it your only recourse to saving the pulley is to make an offset key to fit shaft and pulley which can be a pain in the butt.



Cheers
John
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 08, 2008, 07:50:58 AM
If you do screw up you have another option to cut another keyway further round, not ideal but wont make too much difference to the strength of the pulley. I often have to do this on the pulleys etc for the boats as the keyways have been damaged.

 Another option would be to cut an ovesize keyway to straighten it up then machine a step key to suit.

Obviously the best option is to take care when you do cut it but just thought I would mention the above as it may help you in the future if you need to repair a pulley with a damaged keyway.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 08, 2008, 11:58:14 AM
Some good advice there chaps thanks.
Well I still haven't heard from BSL but my box of bits turned up this morning from AFC. Before ordering I asked them for a price on machining the bores etc and confirmed the sizes I wanted, but alas they couldn't do it and a gent down the road that could was going to double my costs so DIY it was. Only thing is even though I had confirmed the bore sizes with them ie 9.5 mm on all the small pulleys  I got a 10 tooth pulley through the post where the boss and bottom of the teeth only turned out to be about 9.8 mm so I cant use it grrrrrr. HPC had told me I needed T10 on this axis but then I was told no you don't, T5 will do, just make the belt wider. OK I thought that sounds logical for increasing the power capabilities but won't having a smaller pitch mean that the diameter for 10 teeth would be too small for a 9.5mm bore? Nope I was told the max bore is 13 mm on these.  Unfortunately the person giving me the details read the wrong bit in the book or something. Anyway no complaints about their customer service as they were quite apologetic and promise to sort it out first thing on Monday it looks like I can get a 10 tooth and 72 tooth pair with a 1/2 belt if I go for imperial (3/8 pitch) so that's what I'm doing. I did have another radical idea on the keying front and that was due to me not using the handles on the axis any more Id either fix the pulleys to the handle some how or turn down the handle and bore out the pulley to get a nice tight fit and a spot of weld to finish off.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 08, 2008, 12:10:38 PM
Oh did I say I was going to spend this morning trying to powder coat my frames ? What I meant was I was going to go shopping and buy a new bed :)  Bl****dy H*** the price of mattresses and beds...I could get a nice Mill (or even a pulley or two from HPC) for that price I thought. :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 08, 2008, 02:36:24 PM
Just looking back at the pics WantCNC posted my steppers look a lot bigger than his (no not showing off :) ) his look like twin shaft and about 6 mm where as mine have single shaft and 9.5mm. I don't mind them being more powerful than need be it'll mean more scope to up the speed if ever I need too or even go 1:1 on the ratios.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 08, 2008, 04:48:15 PM
LOL, well just think yourself lucky you didnt get the bed from HPC :D

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 10, 2008, 07:52:15 AM
Doesn't bear thinking ABOUT :)
It wasn't a completely wasted day yesterday on the CNC front. I finished putting all the electro gubbins in my rack mounted box and Conected up the motors (yet to finish the plug and socket arrangement). I felt like a right electro newby I couldn't get the steppers to run smooth they turned ok but very juddery. I tried tuning. incidentally when I'm on the motor tuning page my motors don't turn when I press page up and down as per motor tuning instructions  I have to save then exit the tuning to get them to move with the keyboard. Anyway hours wasted trying to tune trying different micro steps etc etc. Then came to the conclusion I must have a cable or two wrong on the steppers even though I was fairly confident this is how I connected them before. I got them from motion control products but unfortunately their PD data sheet for these motors have different wire colours on than mine. I eventually found this site
http://harmonfamily.us/stepper_motor_wiring.htm
Which proved pretty helpful and indeed confirmed I had a few cables wrong. Put them right and the steppers became classical music rather than house music :) Typical I thought if they hadn't turned at all I would have checked the wiring but being a novice I wasn't sure that having the wrong set up on the Acc and velocity could cause juddery motion or even the set up of my drivers...anyway all good now :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 10, 2008, 08:29:16 AM
Yes thats the only thing about the SS, not sure if you will ever be able to move the motors from the tuning window but certainly not possible at the moment.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 10, 2008, 12:45:47 PM
No real problem once you get up and going.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 11, 2008, 07:34:08 AM
The nice Sandra from Anti friction components sorted out my problems with the pulleys. Not only that but her boss is coming past my work place on Thursday so he'll drop them in and pick up the wrong ones without charge. So though I could blame them for a mistake overall I'm pretty pleased with the outcome (at least I will be if all goes to plan). Tonight is powder coating night mark II.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: wantcnc on August 11, 2008, 08:35:48 AM
"Just looking back at the pics WantCNC posted my steppers look a lot bigger than his (no not showing off "

Yes you are :)

you do need to be aware that steppers need to have some work to do in order to run at full speed
to large is not a good thing either... looks like your OK
the double shaft was selected in case I wanted to put encoders on (to check for missed steps)


JB

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 11, 2008, 08:45:04 AM
Belt and braces approach.  What work do I need to do to the steppers ? Would the encoders feed back to Mach 3 via a BOB ? I'm guessing you've dropped the encoder option as you've found them to be pretty reliable as they are? I must admit I've had my steppers for a while and didn't pick them in a scientific manner more like these ones look big enough and 3NM seems about right etc. My Z axis stepper is woefully inadequate though as I hadn't thought of moving a heavy table with it. I'll try and get another stepper the same as the X and Y.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 11, 2008, 08:57:51 AM
Ops sorry I miss read your post. Yep the steppers need to to do the work...not I need to do some work on them.. :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 14, 2008, 01:54:21 PM
Pulleys turned up today. Wow the 72 tooth 13 mm pulley looks big and heavy but I'm sure it'll be ok. The handles that have been on order since I got the Mill (as they were missing) ie the Y and one of the X axis handles also turned up today but unfortunately are the wrong bore so they'll have to go back. I'm thinking I will mount the pulleys on the hand wheels now by turning down the boss on the hand wheel and opening up the bore on the pulleys to get a tight fit then a couple of grub screw retainers to stop them turning. If I feel really brave I suppose I could even thread them but that's a little advance for me.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 15, 2008, 09:28:00 AM
LOl you are not having much luck with the pulleys and handles :D

As for handwheels, I think you will find you never use them. On my first conversion (manual Bridgeport) I kept the handwheels for simple things like surfacing, two months in and I had never used them at all so out came the 9inch angle grinder LOL

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 15, 2008, 12:14:28 PM
I'm tempted to think the same that I'll probably never use them but trying to tread a little cautious. Me and luck so far on this project don't seem to be seeing eye to eye :). I've ordered the Z axis stepper from www.arceurotrade.co.uk  these were slightly more expensive than motion control product but motion charge £10 PnP where as Arc only charge £3.95 so just come in a bit cheaper.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 15, 2008, 01:25:42 PM
Another mistake I've made is the size of the  z axis belt. I had worked out the size and HPC couldn't do that size but suggested the next one up, same sort of thing with the next companies I tried then the pulley got bigger so that meant a bigger belt. The belt I ended up with is much too big (long) still I'll get it assembled and order another one the right size it's a cheap enough mistake to make.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 16, 2008, 07:12:49 AM
Did the same as you the first retro I did so now i get the motors and pulleys mounted before I order belts :)
I have dealt with ArcEuro a ccouple of times, once the courier screwed up, it was the day they shut for Christmas holidays and they went way beyond the call of duty and got things sorted for me, excellent service.

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 18, 2008, 01:47:54 PM
Motor turned up from arceuro today. I'm getting closer now. I'm hoping to borrow an engine lift this week to get my machines on to their stands..at near 400Kg each I struggle a bit to lift them :)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 18, 2008, 02:33:00 PM
Excellent, looking forward to seeing the progress in pictorial splendour ;)

400Kg, thats approx the weight of the saddle and crosslide on my lathe ;)

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 20, 2008, 09:42:50 AM
Ha . Who's showing off now ?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 20, 2008, 01:46:42 PM
:)

Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 23, 2008, 12:15:58 AM
I'm getting closer. I've got the borrow of an engine hoist on Monday. So my machines can finally be put on their stands and I could even destroy some perfectly good bits of metal with them.  Handles have been sent back so don't know how long they'll be to get back to me. I'll have to get some pics done...Maybe tomorrow when I finish painting my frames.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 26, 2008, 04:33:17 PM
well it certainly seems that the saying is correct, "tomorrow never comes "  ;D

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 04:21:22 PM
Ok I got some pics...just godda figure out how to post them.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 04:27:19 PM
Yep I got it. You'll regret you asked I've got a loads of them.  ;)
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 27, 2008, 04:43:42 PM
easy enough, just make sure they are not too large then use the full reply page and additional options button and browse to the location of the pics on your hard drive.
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 04:50:20 PM
just waiting for them to download from the camera.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 04:51:37 PM
I got them lifted on the stands OK and my Chinese ER32 collets and chuck turned up today..
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 27, 2008, 05:07:21 PM
is that the collet chucks from HongKong on ebay? if so then they are ok, the one I got was nice
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 05:32:37 PM
yep...1/4 of the price of a lot in Uk...and seem good kit..I'm not having much luck with these pics... do you attach them using the attach button or the insert image ?
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 05:38:08 PM
Control gear ready to go with a nice smoothstepper.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 05:46:29 PM
My lathe on it's stand..hopefully smaller than the control box.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 05:48:48 PM
third time lucky...This is the mill before mounting ....
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on August 27, 2008, 05:55:42 PM
The mill mounted...and fortunately I've got the hang of this pic posting thing. I've modified the ones above to fit the screen better...
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on August 27, 2008, 06:34:10 PM
Nice pics, will look even nicer next week when they are running from Mach ;D

Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on September 04, 2008, 09:06:36 AM
Ha running next week :) I'm currentely in Romania and will be for a couple of weeks...and I'm not expecting much progress to be made on my CNC project whilst I'm away...(there's just no motivating some folk).
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on September 04, 2008, 09:08:25 AM
Still maybe I'll find some bits of ally whilst I'm here for the brackets. If I had made up a template they could have cast me the brackets here in alloy or cast iron no problem.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Hood on September 04, 2008, 03:37:50 PM
LOL well that will teach you to not be prepared, cast brackets would have meant minimal machining to true up :)
Hood
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on June 05, 2004, 07:16:18 AM
Well I'm back and looking for some time to progress to the next stage. I still haven't recieved the mill handles from chester yet,though they promise today or tomorrow.  Next step to make some cardboard templates to see how I'm gonna mount the motors.
Title: Re: Warco VMc /Chester 626 knee mill CNC conversion
Post by: Perfo on January 30, 2009, 02:22:34 AM
Nothing moved on this project. I've been busy using the Mill and Lathe and getting bogged down in all the other life stuff.