Machsupport Forum
General CNC Chat => Show"N"Tell ( Your Machines) => Topic started by: jab_814 on January 12, 2010, 09:30:30 PM
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Hello,
I am new to this so please excuse my ignorance, I am a newb. I work in a production shop that currently uses 6 bridgeport boss 6 mills none are which are cnc, just nc. There is a series 2 boss 6 that is not working just used to maintance the other boss 5 for parts or boards. The boss 5's run great for the high volume of work that we do for powdered metal parts which we just drill holes here do a little milling there. The only complaint is on a weekly basis an axis might go and we will have to stop production to repair the axis. So reading this forum for about 2 weeks now i am interested to convert the series 2 boss 6 into cnc. After retrofitted I will run the machine in production myself to learn all the pros and cons. If it goes great I plan to convert the other boss 5's in the same manner.
I would like out of all this:
- A more reliable machine
- Finer positioning and smoother motion
- Upgradeable to 4 axis's (rotary table)
- More speed in the rapids, but the same performance as the Boss control will do just fine
- A way to adjust the spindle speed via G-code instead of manually
- Control of coolant, by a M9
- Limits and home microswitches to cut the motor
- Smaller footprint
I plan to use:
- Mach 3 Mill
-Geckodrives (G540 or 3 G203V)
-BOB from CNC4PC (C11 G)
-PC (w/ Touch Screen LCD), if the touch screen lcd proves to be overkill it will be eliminated for the boss 5's
-The original Iron from the mill, along with the table, stock stepper motors, and spindle motor
Lastly I will get a power supply and fuses after I find the major parts for control of motors and misc devices
Am I in the right direction as far as parts go or does anybody else recomend trying something different?
I understand that the G540 is 4 axis and also a BOB, but can it control also coolant and a vfd for the spindle?
Is there a way to rigid tap (G84)?
I will also continue to read the forum to help better educate myself
Any guidance in this project, would be great.
Thanks for reading My post,
Joe
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The G540 will I think be far too small for your motors, even the G203 will likely be on the small side for the old Bridgeport steppers but a few people do use them. Might be wise to look at getting modern motors but that will more than likely mean you would have to make up new mounts and possibly even shaft extensions.
I have done a BOSS 6.1 series one Bridgeport and its been working well for about 4 or 5 years.
You are not going to be able to do rigid tapping unless you convert to a servo spindle but semi rigid with a floating holder is possible with a normal induction motor with VFD control and thread milling can be done with any spindle setup.
Hood
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Thanks for the reply
- As far as the motor drives go, what do you mean as " too small for the motors"
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The current rating and voltage of the G540 will be too small for the big steppers that a Bridgeport will have, the G540 is only 3.5Amps and 50v Max.
Hood
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I see that on this forum as well as the cnczone that alot of people are retrofitting using the geckodrives. I also noticed a post on the cnczone that someone posted that the boss 5 stepper motors are around 8 Amp. The largest geckodrive supports 7A and 80VDC. Is there other drives that satisfy the big steppers in the BP that anyone has tried succesfully. I would be using this as a production machine and not a hobby machine. Thanks
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Some of the Leadshine drives are 9 amp but to me your best bet would be to get new steppers and use G202/G203.
Well actually your best bet would be to upgrade to servos.
Hood
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A lot will depend on your budget.
How much can you afford to spend on your upgrade?
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I hope I could use the original steppers and spindle motor, because their are 6 boss 5's that I would like to convert over if the boss 6 seems to be more reliable and accurate.
I hope I could get the same rapids and feed as the old control
These would be used for high production such as a continious loop of drilling cycles and small milling passes.
As hood mentioned before the old steppers need more amperage than what the geckodrives have (7A 80VDC)
Basically, I want the same capabilities that the boss 5 controll offers already but I just want them more relaible such as when someone is running them in the middle of the night I don't get a phone call saying that an axis went out, which would require me to go down and fix it.
So as cheap as possible with respect to reliability and speed I was hoping maybe a 1000, which would not include the cost of a PC and Mach3
I have read that some people kept the power supply that the bridgeport already had but maybe modded it a bit
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What rapids do you get at the moment?
Any gearing between motor and screw?
Is the spindle controlled from the control or is it totally manual?
I did a series 1 boss 6.1 (see pic) with new motors, geckos, PMDX breakout and made a power supply and it was probably less than $1000, was a few years ago so I dont remember exactly but steppers and drives are now cheaper.
Hood
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I have not done any retrofitting yet still in the process of selecting components for the build.
The rapids would be whatever it was originally stocked with
Gearing would also be what it was originally stocked with 2:1
Manual spindle
Hood do you have steppers and what rapid do you get with reliability
Also beautiful job on the 6.1, Wow
Would of you considered or did anything different to your conversion
thanks
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Yes it has steppers on it, gearing if I recall is 2.5:1 and I get 2500mm/min (100ipm) which was the original rapid. Having said that yours is a series 2 it will be a much heavier machine so not sure how yours would perform.
If I was doing it again I would have AC Servos on it and I am actually considering doing that, I have just about finished doing a Beaver Mill which is about the same size as a series 2 Bridgeport and it originally had DC Servos which I swapped out for AC and what a difference compared to steppers :)
If you stayed with steppers you should be able to do it for $1000, you would need 3 drives, a power supply and a breakout and my preference would be new steppers as well.
Steppers would likely be around $100 to 150 each, drives probably around $100 to 130 each, breakout board under $100 and building a power supply should be around $100 I would imagine.
Hood
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What would be the advantage with a AC servo than DC servos, would you have to buy something extra or different to run that type of servo, other than BOB, servo drives, encoders.
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What would be the advantage with a AC servo than DC servos, would you have to buy something extra or different to run that type of servo, other than BOB, servo drives, encoders.
AC servo do not have brushes therefore they do not require as much attention. you must have Drives that match what motors you are using.
archie =) =) =)
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Hood
what AC drives and servo's are you looking at if you do not mind me asking
archie =) =) =)
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I use Allen Bradley DSD or Giddings and Lewis DSA drives, they are one in the same just rebadged.
I used the Bridgeport a few days ago for the first time since I have had the Beaver up and running and I couldnt believe how slow it was, you sure get spoiled with servos ;D
I am definitely going to put servos on the Bridgeport when I get time, I have drives/motors here that are just on the small side for the Beaver mill but will be perfect for the Bridgeport :)
Hood
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Ok,
Yesterday, I finished building a PC to run this thing.
CPU P4 3.2 Ghz HT
MEM 2 GB PC 4200 Kingston
HDD 40 GB SATA
GPU 256 MB NVidia 8400 GS
LCD ELO 15 " Touchscreen (Resistive Type)
OS XP Pro 32 bit
Today, I have just ordered a PMDX122 BOB and 3 203V's. I am going to use the original Steppers and spindle for now, just so I can play around with functions in Mach3; wiring, tuning, and moving. While I am waiting for the parts I am currently going to start building a power supply or I might buy one if feasible, Any Suggestions?
The reason I picked the PMDX122 and 203V's is:
Most of you are using that board for the bridgeport boss and it seems to be adequete and reliable.
The 203v's I got just because I liked the protection that was on them, I am a noob
I do have a Question though as far as some of you are using the smoothestepper with the PMDX122, what is the advantage I am confused. Some say they could not get it to work with their system and some say it works great. Why do some incoporate it?
Thanks Joe
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The SmoothSteppers big advantage is that it does the pulsing so the computer doesnt have to, it makes for a nice clean pulse. On my Bridgeport I never really noticed any difference in what I could get but the motors do sound nicer.
I also use the SS on my other machines and the big advantage with them is they have the servos with 8000 pulses per rev on the encoders so the parallel port just cant pulse fast enough to get any decent rapids.
Think the biggest problem with the SS is it shows up any noise issues you have in your wiring where as the parallel port is more tolerant, personally I have never had any noise issues on any of my machines when using the SS.
Hood
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Hello,
Could this all be powered by a PMDX-135-8020 power supply and a Hammond Manufacturing
Transformer, Toroidal Power; 1000VA; Chassis; Pri:117/234VAC; Sec:Ser 48VCT, Par 24V
The PMDX-135 is a power preparation module for use with CNC motor drivers
Offered in 80 volt and 50 volt versions
Supplies up to 20 Amperes of filtered, unregulated DC when connected to a suitable input transformer
Includes electronic load "DUMP" to help prevent overvoltage when motors produce "back EMF" during rapid deceleration
Provides rapid power off discharge of storage capacitors (under 5 seconds) for additional user safety
Utilizes multiple filter capacitors in order to better handle ripple current heating effects
Utilizes heavy duty bridge rectifier mounted to a large heatsink
Indicators furnished for "DC Output ON" and back EMF "DUMP"
Ideal power source for our PMDX-132 Breakout/Motherboard Combo for Geckodrive stepper motor drivers
Can be used to power all models of Geckodrive stepper and servo motor drivers and also drivers from many other vendors
Has enough power capability to run 4 Geckodrive stepper motor drivers at full power
As far as a power supply and a transformer I have no idea how to design one and i'd rather and feel safer if i bought something that would work than fry something or myself.
Let me know what you huys think when you have time, thanks
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Bob Campbell has a nice PDF on building a power supply, have a look here http://campbelldesigns.net/files/power-supply-part-1.pdf
It will let you see how to calculate the required power and capacitance.
Hood
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I just read this conversation and thought I would chime in.
I completed a BP Boss6 retro a few months ago and all has been running great.
I used the following:
3- Gecko G212
1- Hillbilly's BOB
1-KL-7220 20amp 72V power supply (from Keling inc)
1-Smooth Stepper
1-ELO Touchscreen
I kept the original steppers and when possible the existing wires. I added some relays to allow mach to turn the spindle on/off and switch directions. I'm also controlling the coolant through mach.
I am getting 100ipm currently. I ran it at 120ipm for awhile but wasn't really comfortable at that speed.
I had originally used the original BP power supply but I could only get about 45ipm out of it and even then I would lose some pulses every now and then.
It's a great machine now. Wish I had another one!
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thanks for the responses,
did you guys use another way to power the spindle or did you power it with the made or bought psu and transformer?
Can i use a vfd with the supplied spindle on the Bridgeport and do you recomend any vfds?
Would you definately use a smoothstepper for this retrofit or would you do without one?
Also keep in mind that i will be using this machine as a high production machine. I do not know what to expect I hope it will be as durable as the boss control if not better.
Just curious using a g203 gecko over all the others with the same specs. Should of I picked a different gecko for my application or are they all the same except 203 has more protection?
Thanks again
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thanks for the responses,
did you guys use another way to power the spindle or did you power it with the made or bought psu and transformer?
Not really sure what your asking here as the spindle motor on my BOSS6.1 was at mains voltage so no transformer was used.
Can i use a vfd with the supplied spindle on the Bridgeport and do you recomend any vfds?
Yes if its a 3 phase induction motor you can use a VFD, personally I have found that you will lose a lot of torque when you go below about 20% -30% normal speed with a VFD so I kept the variable sheaves as well and just adjust with a combination of VFD (external pot ) and sheaves. As for VFD afraid I have no recommendations, I have two I have used, a Mitsubishi and a Hitachi and both work well.
Would you definately use a smoothstepper for this retrofit or would you do without one?
Personally I would but probably no huge benefit if your computer can put out a nice clean pulse. The good thing about the SmoothStepper is if in the future you decide you need it there is very little rewiring to do, all you would need is to remove the cables from the parallel ports and plug into the SS.
Just curious using a g203 gecko over all the others with the same specs. Should of I picked a different gecko for my application or are they all the same except 203 has more protection?
Geckos are about the best stepper drives out, as for the models of Geckos I think they are all basically the same with the exception of the protection as you have said.
Hood
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Hey guys,
Few questions, still confused about the power supply
Does anyone know what the specs are for a bridgeport stock stepper p/n 025805, Amp, Volt, inductance ?
Reason for inductance is that the manual for the gecko drives say if you know the inductance you can find the optimal voltage required for the motors.
What did you guys use to heatsink the geckodrives?
Timmy: just curious why did you pick that power supply with that voltage?
are you original motors above rated above 7Amps ?
Do you have these wired in series or parallel?
Are you using half windings?
I know that some are using the geckos and the stock steppers at 8+ Amps max, how are you guys making sure that the drives do not exceed 7 Amps so they do not destroy them. If you had the drive open at 7Amps wouldn't the steppers want to draw more than the rated amperage of the drives and burn them up or shut them down?
Just confused and anxious to try to get something going thanks again guys.
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I have never found the specs for either the Superior or the Sigma motor but I did come across the specs for a similar stepper and I used these to choose my power supply.
Size 42, 7.1 Phase Current, Inductance 2.0mH, Maximum Voltage of 140V.
On my G212's I limited the current to 6.5A (just to be safe).
For a heatsink, I mounted the Gecko's to a 1/2" aluminum plate and then mounted that plate to the existing BPII door/heatsink. I used heat transfer paste between all surfaces.
I also enabled the AUTO CURRENT REDUCTION on the Gecko's.
My motors are 8-wire and are wired series. My motors never are hot to the touch. I would guess they never get above 105degF and usually stay below 92-95deg.
I was reading roughly 54VDC using the original BP supply and could hear the steppers running "soggy". My rapids were a lot slower than what they should have been. When I decided to install a new supply I wanted something that had enough current for 4 axis (in case I ever got around to setting up a 4th). I had read on one of these forums that your could get higher rapids by going to a higher voltage supply as long as you didn't go over the motors max voltage or run into a heating issue. With this in mind I decided to go as high as I could but stay below the max voltage the Gecko's could handle. With the amps I needed and the voltage I was going for, that supply was the only one that fit.
I immediately heard the difference with the new supply. I doubled my rapids and my steppers sound much tighter.
I am still working on an easy/clean/cheap method to control spindle speed but for now we do it manually.
Hope this helps.
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Thanks for the info,
I forgot to mention that I have decided to retrofit a boss 5.1 instead of the 6.2. The reason is we had two sold to us 2 weeks after this post was created.
One was in bad shape as far as the old boss 5 control and the other was really good. So i used the bad shape machine, iron was still good.
I hope this doesn't change anything I am assuming that the only difference is the gearing between the two machines and that they used equivalent motors to run both models.
Timmy what was the similiar stepper from, another bridgeport boss or another stepper from a machine.
Thanks for your help
I plan on ordering a psu and transformer tonight, will update
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The specs came from an Ametek size 42 stepper from another machine. They won't be identical, but close enough for what I needed.
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Timmy are you saying you used the stock sigma or superior motors on your retrofit or you use that other stepper just as a model for your setup since you didn't know the specs.
The Ametek size 42 stepper is not on your machine right.
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I have the stock superior steppers installed.
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Hi guys,
Right now i got the machine moving
I used for now
revs per @ 10000
vel @ 40
Accel @ 2
Geckos 203v 76VDC and 7A
using original steppers
I am still playing with parameters to find the best range, any suggestions?
Also I am looking into a vfd, I am currently interested in hitachi x200 or sj200
Can anybody tell me the difference between the two My understanding is x200 has variable torque and the sj200 has constant torque .
I can get the x200 for $202 and the sj200 for $279
Would anyone recommend one over the other
Also would this be able to plug straight into a pmdx-122 board or do i need some add on.
Thanks again expecially hood and timmy, wouldn't been able to do this without your guidance
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(http://i801.photobucket.com/albums/yy293/jab814/cabinent.jpg)
(http://i801.photobucket.com/albums/yy293/jab814/Bridgeportfront.jpg)
(http://i801.photobucket.com/albums/yy293/jab814/Limit.jpg)
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Joe,
Good job on the retrofit! I did a Series I BOSS 6 and kept the original steppers, Gecko 203's and run then @ 65V/7A. I have had no problems at all for the last 2 years. I also limit my speeds to 100 IPM. Just be aware that your BOSS 5 has no gearing (belt) so your speeds will be slower. Boss 6 and newer have a 2.5:1 drive. I think you will be well served for putting these machines back in production if they aren't wore out. Mine still holds tenths. I reused as many parts as I could to save on components including the original (modified) heat sinks for the Geckos.
Good job.
Dean