-
Looking to pull the CNC conversion trigger
Greetings!
I guess this is part introductory post and part first build thread (I hope) post. So I've been a member since 2010, purchases a PM-45 mill to learn and hopefully convert to CNC in 2012, and am finally getting around to prioritizing that as my main side project. I've done a little manual machining with it here and there, but find it a little frustrating without any sort of DRO on it like I have with the mills at my current job. There, I've used two different knee mills, one with just a DRO, and the other with an XY cnc conversion running prototrak software that I did get a chance to program once or twice.
As for a little background about myself, I've been in the automotive industry for over 10 years, starting out in parts sales, then fabricating/welding, then technician/fabricator, and finally left that industry to work in aerospace. Fabricating and welding are great, however I've grown to love the precision and repeat-ability that can be had with machining. Which brings me to today--trying to take a fancy tool in my collection and upgrade it.
My plans right now are as follows:
-Buy and build the electronics portion of the machine
-Bench test the above
-Buy ball screws, nuts, and machine any brackets/spacers/etc needed to install on the machine
-Machine grooves in the ways for oiling purposes while everything is apart, and add a 1 shot oiler at a later date. Plumb what I can in the meantime.
-Use the mills at my job to do the above machining where possible and gain more seat time machining and with solidworks
-Assemble, Test. Debug, Make cool stuff
-Convert to belt drive, stronger motor, and VFD
-Add power drawbar
-Maybe convert to a different spindle and/or a Tormach Tooling setup
Hopefully I'm on the right track here, which is the reason for my post. While I may have joined all the way back in 2010, I lurked once in a blue moon and then more so just recently. I looked at the CNCcookbook site and took in what I could and understood at the time. I also just read through gd.marsh's thread and had also read at one time jid2's build but now want to re-read them thinking I can take in more now that I have a better understanding. Unfortunately I don't know everything right now, and having a 3 month baby around doesn't let me get online anymore like I used to so this is where my questions come into play. At this point, I have the bug bad, and really want to start accumulating parts for the build but the direction of where to go and what to buy first I just don't know what's best yet. I've narrowed it down to the following two sources I believe are the way to go, so correct me if I'm wrong.
-DMM Tech AC servo kit. I'd basically buy everything they have listed on their multi-axes kit page here, sans the power supply since I'd go with a 72v one instead
DMM | CNC Systems | AC SERVO DRIVE | AC SERVO MOTOR | ROTARY ENCODER
The other option is to piece together a kit through Keling/Automation Technologies since they seem to have everything whether I'd want to do stepper or servo.
So while it's getting late, I'll try to sum it up and ask am I on the right track? Which would be the better choice? What is the difference between DC and AC servos other than one not needing to be converted from the power supply? Is it worth trying to go steppers to save a couple bucks? (More money for other mods) And if there's anything I'm forgetting please mention it.
Thanks.
-
2 Attachment(s)
Re: Looking to pull the CNC conversion trigger
Just another post to hopefully encourage some replies.
Here's my machine hiding in the mess of some of my other tools tucked in the garage. My cardboard box chip shield can only help so much haha.
Attachment 277338
And then while doing some window shopping on Keling's site, here's what I've selected as a start. I'm not sure which USB board to go with, but I do know I'd like to not use the C10 or C11 boards offered in their kit. Any advice on either board?
Attachment 277340
-
Re: Looking to pull the CNC conversion trigger
i think that usb card is redundant as the smoothstepper you have shown there comes with a breakout board.
For what it's worth, I have a USB smoothstepper connected to a C10 breakout board in both my mill and lathe conversions, and I have no complaints to date.
-
Re: Looking to pull the CNC conversion trigger
Right, I was just listing both usb boards but would only chose one. I'm also thinking of an Ethernet connection board now too. Too many options....
Initially I see myself running the machine with my current laptop and then setting up a stand alone system that stays with the machine so I'm fine with either type of board above--just not one that uses a parallel port.
In preparation for making ball screw bearing mounts, I just picked up a Shars boring head kit off ebay last night that should be coming this week. Time to start adding more to the collection than the standard clamp and vice kit that came with the machine.
-
2 Attachment(s)
Re: Looking to pull the CNC conversion trigger
A couple goodies showed up today. I settled on the Nema34 1128 oz-in closed loop hybrid stepper motor kit and also went with the ethernet smooth stepper, which will also use the c10 board in the kit. The boring head also showed up, but no pics of it yet.Attachment 277986
I also began drawing up the motor based off of the metric dimensions on Automations linked file but may start over now that the motor is in hand.
Attachment 277988
-
Re: Looking to pull the CNC conversion trigger
same steppers i have. I think you'll like them. :)
-
Re: Looking to pull the CNC conversion trigger
Are you running them as direct drive, or with a geared down belt and pulley setup? Right now I'm planning to do direct drive for the X and Y, but pulley for the Z along with gas strut assistance like I saw gd.marsh did.
-
Re: Looking to pull the CNC conversion trigger
I'm running all axis on a belt. 2:1 for x and y and 3:1 for z
-
1 Attachment(s)
Re: Looking to pull the CNC conversion trigger
I decided to make my own enclosure so I can put that money towards other important parts. Luckily I had a sheet of 1/8" aluminum around from past protects as well as 1/16" steel that I'll be using as the insert panel. The layout will go something like this, leaving room for a 4th driver and then fuse and terminal bars.Attachment 278278
-
Re: Looking to pull the CNC conversion trigger
-
1 Attachment(s)
Re: Looking to pull the CNC conversion trigger
Robbing Peter to pay Paul, or something like that....I pulled apart my spindle and coolant switch housing last night hoping to find a 220 to 110 transformer. Right now my machine is ran on a 3 wire 220 outlet, so I thought it was stepped down for the light and the pump. Wrong. The light is 24v and the pump appears to be 220--i should have looked in my manual first. Either way, I was going to need that transformer in the box. Luckily, I do have a 4 wire 220 outlet in the garage that my machine can get it's neutral wire from and give me my 110 for the internal outlet.
Attachment 278388
-
Re: Looking to pull the CNC conversion trigger
Who ever did the conversion on my mill had it setup with a 220 plug, and a handful of 110 plugs. I finally redid all of the electrical and wired it for a single 220 plug with a neutral. For the outlet, I just pulled new wire and added the neutral to my outlet. You could probably even just pull a neutral wire, and leave the rest.
-
1 Attachment(s)
Re: Looking to pull the CNC conversion trigger
That's the plan-- there's only about 12' of conduit between the 220v source with a neutral wire and my machine's outlet. Should be easy to pull just one wire.
Today I finished up the panel's mounting solution. I laid out everything, rough marked it, then cleaned things up with a square ruler. The nut rivet tools is one of my favorites in my collection! Attachment 278504
-
1 Attachment(s)
Re: Looking to pull the CNC conversion trigger
A little bit of progress. I have a DPST switching 220v relay coming tomorrow that will fill the empty spot in the middle area. Hopefully this week I can test out my wiring and see if a motor spins. Attachment 279086
-
Re: Looking to pull the CNC conversion trigger
Looking good so far. You made some good choices with the electronics as well.
I know enclosures are expensive, but I found a supply of nice ones at a very nice price too.
LARGE WHITE ELECTRICAL ENCLOSURE
I buy a lot of stuff from them and wish they would have had them when I was looking before. :(
Good luck with it and I will stay tuned. :)
-
Re: Looking to pull the CNC conversion trigger
Wow, that is almost too hard to pass up. I'm wondering just how tight of a fit my panel will be placing it inside since it's right on the money at 19" x 19" and so is the interior dimensions--unless they're counting the folded over lip at the doorway. I'll have to measure the driver height too and see where I'm at. What I was hoping for is making my enclosure 22" x 22" leaving enough room for any switches and fans hanging through to the inside, and now that I think about it I will have to probably pass on that panel. Right now I only get to work on this setup while at work during my breaks since it's sitting on my desk there. Not much time at home to do anything but take care of the kiddo.
Speaking of room for the fans though, anyone have first hand experience with these?
Quiet Cooling Fan System with Thermostat Control for Home Theater AV Cabinets | eBay
And also, while wiring up what I could today, there was a 7th wire for the encoder extension cable that looked "bundled up" with heat shrink. I'm suspecting it's for shielding purposes but am not sure. Doesn't say anything in the driver wiring instructions that I can see.
-
Re: Looking to pull the CNC conversion trigger
So this morning I went in to work extra early all excited like a kid on Christmas, thinking I could temporarily rig up the power supply to 110 and get things started. Well, that I did, and also successfully had 5v power going to the smoothstepper and BOB. I pulled my fuses to the drivers as well as unplugged the signal wiring going to the X axis driver just to make sure I setup the pin-outs right. At that point, I realized I didn't do enough homework to see what had to be configured in Mach4--software of which I have had no experience with, nor previous versions. I went into the stepper plugin and changed the I/O settings for just the X axis and I believe also changed some configuration with Mach, and the most I got was 5v at Pin 2 and 3, dropping to 0 if I pressed the left or right arrow keys. Otherwise there would be constant 5v between those pins and the common 5v in the middle.
My BOB jumper is set for Pins 2-9 as outputs, and I wasn't sure where to set the pull up or down jumper--pulling up I believe is when I could get either 5v constant or 0v during arrow keys. I'll have to read more into settings later (baby needs me now) but if anyone can give some basic setup instructions regarding outputs, active lows, enables, etc, that would be helpful. Thanks.
-
Re: Looking to pull the CNC conversion trigger
On the right track and have two motors turning--the third is at home so I couldn't wire it up temporarily.
https://www.youtube.com/watch?v=q0Gy...r#action=share
-
3 Attachment(s)
Re: Looking to pull the CNC conversion trigger
Nothing too exciting to post, but there are some new things at least. I ordered a few things off of ebay for the enclosure, one being a fan, a power switch, emergency stop button, and xlr style connectors for motor wiring. I figured these things were pretty important in getting the enclosure figured out, holes cut, and important wiring mostly done. The fan just showed up today, while the other parts are most likely on the slow boat.......literally. The enclosure sheet metal I haven't touched in days, and the control board I added nut rivets to for the 220 relay but that's it. Everything should be coming off of that shortly for painting but I'm not sure how soon that will happen.
Attachment 280366
Attachment 280368
Attachment 280370
-
5 Attachment(s)
Re: Looking to pull the CNC conversion trigger
I'm currently working on the enclosure as seen in the following pictures. Still left to do is drill holes at the rear face for XLR motor connectors, as well as route power supply to the work light and coolant pump. I'm thinking about using an XLR for the work light and have it detachable but for the coolant pump I believe that runs on 220v so I'll have to figure out what do do there. I don't think I can use an XLR for that type of power.
Some things I'm missing and still waiting on for the front panel is a green power light for next to the coolant switch, an ethernet panel mount cable, and some spiral cable wrap.
Attachment 282038
Attachment 282040
Attachment 282042
Attachment 282044
Attachment 282046
-
Re: Looking to pull the CNC conversion trigger
Slow in the progress department but its a step forward.
https://youtu.be/bz2KFdIt8ds
-
7 Attachment(s)
Re: Looking to pull the CNC conversion trigger
Electronics are complete and the enclosure is done, sans the lid. I also now have power to my mill again after stealing some components and the spindle direction switch for this build. All 3 axis spin and seem to work fine after generating some g code in CamBam but I don't have things configured right just yet for the ballscrew pitch I'm looking to use. Still trying to figure out where that setting is in Mach 4 as I've had no time to play with it hardly.
Everything in one shot.
Attachment 285602
Front Panel: Estop/Off, main power on momentary switch, spindle direction/power switch, coolant power light, coolant power off/on switch, xlr connection that will be for c10 estop and limit swiches, and my ESS Ethernet connection.
Attachment 285604
My attempt at cleaning up the wiring.
Attachment 285606
Hinges and dual cooling fans.
Attachment 285608
A,B,X,Y,Z motor plugs, and encoders below, spindle power connection, coolant pump connection, xlr is for work light dc power, and 220v inlet power is on the bottom.
Attachment 285610
The mill still in its torn down and in need of a cleaning state.
Attachment 285612
My bench testing helper.
Attachment 285614
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
So I've done a couple of test runs with the x and y axis and there's a clicking coming from one of the x ballnuts. When I run a program I only get so far until the x driver faults and stops working. I may have too much preload on the nuts causing this problem, or there's a finishing issue with the nuts similar to what Jid2 saw in his build. For now, I plan to shim out the nut flange from the machined bearing block and see how that goes. If anyone has any other ideas please share.
More pics to follow...
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
I needed a way to tighten down my a.c. bearing nuts and hold the ballscrew at the same time. The drill chuck kind of worked for gripping but would slip eventually under too much torque. I started with a 7/16" shaft collar, and made the following. Its made to use a 17mm wrench.
http://uploads.tapatalk-cdn.com/2016...831c57598b.jpg
http://uploads.tapatalk-cdn.com/2016...753e2881ad.jpg
http://uploads.tapatalk-cdn.com/2016...c548196540.jpg
(not fully installed because I'm in the middle of working on something else)
After cranking down on the a.c. nut, I saw I still had slop in the bearings-- at least .020 or more, easily visible when changing direction turning by hand. With a quick theorizing and bench test, I believe what is happening is the bearing outer races need spacing apart to leave a gap for the inner races. I suppose this is what I get for eBay ( linear motion bearings2008, mind you) parts. My theory was tested out by inserting mig wire as a shim between the bearings.
http://uploads.tapatalk-cdn.com/2016...dcb3f8be58.jpg
http://uploads.tapatalk-cdn.com/2016...47d36f5a34.jpg
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
Just searched and saw this problem with the bearings is common and that shims are usually required. These bearings were also assembled the same direction as others have seen. Time to look for proper shims so I don't overload them.
http://www.cnczone.com/forums/linear...fxied-end.html
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
I'm currently in the process of taking the x and y axis apart to shim those angular bearings and pack them with grease. The z axis needed about .012" worth of shims. I had to cut them by hand since my metal disc punch set only could do the internal size (3/4" max punch). It currently moves up and down nicely but the spindle, gearbox and motor are still off.
I also picked up some tormach style tool holders off of eBay from YS machine-- going to give them a try and hope they're good enough for my needs with minimal runout.
http://uploads.tapatalk-cdn.com/2016...59487c8b68.jpg
-
Re: Looking to pull the CNC conversion trigger
-
Re: Looking to pull the CNC conversion trigger
First chips under CNC!
http://uploads.tapatalk-cdn.com/2016...6ed53c4b04.jpg
http://uploads.tapatalk-cdn.com/2016...119e2e178b.jpg
The sidewall finish isn't the best but I realized after the fact I had cam bam set to conventional milling for that profile. I also didn't set a deep enough depth for the thru holes and left them with the same .005 remaining stock on the bottom to clean up in post machining.
Time to do limit switches, pump and light wiring, and gas struts next.
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
Good work. A couple of questions. Did you ever find the shims for the bearings? Mine have the same problem and its been years since I looked at them but I know the Z has a big problem with back lash, and a lot is in the bearings when I have the gibs tight (ballscrew moves up and down measurably).
Also on Z I see you used 2 ballnuts nuts. How are they preloaded / spaced? It looks like both are hard bolted to the ballnut adapter.
Mike
-
Re: Looking to pull the CNC conversion trigger
For the shims, I ended up making my own. I used disc cutters to punch out .003" stainless from a roll I bought from mcmaster. The OD turned out to be right around 1-1/4". The ID I made 7/8" to clear the inner race with room to spare. Turned out only the z axis bearings needed shims, as the x and y were a different brand and had proper spacing between the two bearings
http://uploads.tapatalk-cdn.com/2016...465e516979.jpg
http://uploads.tapatalk-cdn.com/2016...54028a5a20.jpg
For the z axis, and actually the others as well, I made the ballnut bearing blocks as close to the actual thicknesses I measured between flanges. Any preloading was done by being a hair under that thickness and if off too much then I used the .003" shim material again to fill the gap. This gave me a 0.000-.002 range of preloading.
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
91TSiGuy,
Where did you procure the disc cutter from? I would like the exact same unit.
Live from downtown Burbank, home of the endless Cup-O-Joe.
JoeyB
Quote:
Originally Posted by
91TSiGuy
For the shims, I ended up making my own. I used disc cutters to punch out .003" stainless from a roll I bought from mcmaster. The OD turned out to be right around 1-1/4". The ID I made 7/8" to clear the inner race with room to spare. Turned out only the z axis bearings needed shims, as the x and y were a different brand and had proper spacing between the two bearings
http://uploads.tapatalk-cdn.com/2016...465e516979.jpg
http://uploads.tapatalk-cdn.com/2016...54028a5a20.jpg
For the z axis, and actually the others as well, I made the ballnut bearing blocks as close to the actual thicknesses I measured between flanges. Any preloading was done by being a hair under that thickness and if off too much then I used the .003" shim material again to fill the gap. This gave me a 0.000-.002 range of preloading.
Sent from my VS985 4G using Tapatalk
-
Re: Looking to pull the CNC conversion trigger
I bought the one pictured above from Amazon and used another one from work for the ID. There's a round model on there that includes both 7/8" and 1-1/4" which is what sizes I ended up needing to make the shims but I don't know how well it'll hold up as stainless cutting stainless.
SE JT-SP310 Locking Disc Cutter Set (10 Piece) https://www.amazon.com/dp/B00CPTXKCO..._WFLCxbMH9V87X
Sent from my VS985 4G using Tapatalk