Messages

281

General Mach Discussion / Re: THC moves on the Z axis...

« on: February 13, 2016, 07:36:07 AM »

Spent the morning ripping my Z axis apart to replace the 10x2 screw & nut with a 10x4 combo.

This seems to have helped but my question is this - it now has the ability to be tuned from the previous 1500mm/min to 3000mm/min easily so should i take advantage of that or will make the problem return?

... this one is an interesting point that I'd be interested to know the answer to.

Your mechanical advantage has halved  (TR10x2D to TR10x4D).... hence if the motor stalled at 1500mm/min..... are you sure that your machine will make 3000mm/min, simply because your leadscrew pitch has doubled .... but your mechanical advantage halved?

282

General Mach Discussion / Re: THC moves on the Z axis...

« on: February 13, 2016, 07:32:07 AM »

As fast as it stays reliable and avoids occilations.   ALSO check your setting in Scam for pluge rate for Z After the pierce. THAT helps with avoiding that dimple you may see on pierce.  It does not help to have a fast Zdrive unless you actually use it (;-)

(;-) TP

.... any suggestions on plunge rate for sheetcam to avoid dimple on pierce?

283

General Mach Discussion / Re: Reference Home Error

« on: February 10, 2016, 01:20:57 PM »

why don't you post your XML profile file, which can be found normally in c:/Mach3/profiles/ then select the folder that matches the profile name listed on the screenset when you start mach.

You will need to call the XML file something unique or it will not upload like coachm.xml

What sort of a breakout board is it?

What pins have you wired the limit switches to on the BoB?


Did it all work before the installation of the ceramic caps (except for the phantom limit switch trigger)?

That being the case are your sure the caps have been installed correctly? 

Did you try changing the debounce setting?

Do you have a motion controller or does the BoB connect directly to the PC via the parallel port?

If you provide as much information as is possible then someone can have a go at diagnosing the issue.... I've yet to hear the complaint of providing too much information....

pictures?

284

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 07, 2016, 12:21:49 PM »

The original poster is using a smooth stepper... Set the kernal speed at 25khz and leave well alone is the advice given on the warp9 forum.

285

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 06, 2016, 03:26:20 PM »

I think I've learnt more from him in the last few weeks than I have reading stuff... <><><>removes hat

286

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 06, 2016, 03:19:37 PM »

Hahaha.... Yeah I'm very very quickly learning that.... Everything I read seems to be turning out to be wrong...

Aghhh.... I hope someone will keep their eye on the manuals for m4 and keep them current and useful

287

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 06, 2016, 02:44:30 PM »

is G8 a valid code with Mach3?

http://machmotion.com/cnc-info/g-code.html
http://machmotion.com/documentation/Software/Mach3/Mach3%20GCode%20Language%20Reference.pdf

288

General Mach Discussion / Re: Mini-Mills - any good???

« on: February 06, 2016, 01:33:28 PM »

Yup, just a chassis.... I took the decision to buy some trusted drives and motors given I had a bob, power supply etc, and didn't have the space for another drive box.... the plan is to link in the other stuff into the same drive box (hence try to use all the same stepper motors.... [right or wrong])

I didn't think you'd beat a bridgeport... what about converting it?  (must have been done)

I wanted something really for PCB's and small stuff, aluminium / wood (kids sort of wall art nothing high precision)...

289

General Mach Discussion / Re: Mini-Mills - any good???

« on: February 06, 2016, 12:53:56 PM »

Dave.... me again haha (turning out to be a right royal PIA....)

I got one of these (1605 ballscrews) .... along with a 64mm spindle mount [just asked for them to swap it at no cost] ..... and a Makita router (note it only comes with a 1/4" collet .... you can use a collet sleeve if you want to use 1/8" bits, but being the perfectionist.... I got the right collet from the US)
http://www.ebay.co.uk/itm/CNC-3040-Frame-Ball-Screw-Alloy-Router-Milling-Mechanical-Kit-Aluminium-Diy-New-/171640434692?hash=item27f6913004
http://www.screwfix.com/p/makita-rt0700cx4-2-710w-router-trimmer-240v/10140 (although I didn't pay that price [they are avail cheaper])
http://www.elairecorp.com/makitaroutercollets.html

Personal choice.... I gave up with spindles ..... seems like a bit of a game of roulette if you end up with a ceramic bearing one or not... plus water cooling it etc sometimes (dependant on size you desire), hence more complexity.

When I get the time I'll be adding a Super PID to it.
http://www.vhipe.com/product-private/SuperPID-Home.htm


What I've done with mine is I'm using the third port of my ESS to drive a separate set of AM882H drives within my same driver control panel (plasma cut for all my various bits, including PC stand and monitor stand [may weld some trolley type wheels on it at some point...])

To be fair I haven't finished the drive case as I'm trying to allow space for whatever THC I end up with in the end [future proof]

Hope it helps.

Intention is to do some PCB work on it .... and aluminium too but we'll see (I've got two proper non cnc mills and a very old lathe and I intend to convert them but time is short).

290

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 06, 2016, 10:12:30 AM »

Stirling, thanks for that, I learn't something with (a) [never considered].

(b)... can you not tune out with digital programmable drives?   (Leadshine AM882)

Say I'm using 1/2 stepping on a plasma z (because I've not got the right leadscrew... yes!) ... 2mm / 200 steps / 2 micro steps... 0.005mm / step

Or if I'm using a better l leadscrew (10mm pitch).... 10 / 200 / 2 = 0.025mm per step .... or would I be better with 4 u Step resolution or some other custom number?

Something I've never known... can you set a stepper drive with a microstep resolution of 5 (odd number multiples).

Thanks for the time & guidance.

__________________________________________________________________________________

Back to the OP & helping

With regards to the external motion controllers and buffer under flow..... would increasing the lookahead not help and also changing the SS velocity update frequency too?

Lookahead is presently set at 100 lines, and the velocity update frequency 1kHz..... although you'd need to reduce the update frequency to increase the ESS buffer  (or reduce your step frequency update too.....  which is 128kHz..... hence halving the ustep resolution will allow for the ESS step frequency update to also be reduced to 64kHz)