My X3 CNC Conversion

[cadmonkey]

Just thought I'd share with everyone my X3 conversion. All the information gained from the fine folks here and on the EMC2 mailing list went into this puppy. Gallery Here

It's still a work in progress and I plan to post detailed drawings and models so that others can emulate if they choose.

Simply put it's 300 in/oz steppers on the X and Y direct drive, 600 in/oz on the Z at 2.6:1 ratio via timing belt. All the screws are Nook 0631-0200 XPR precision rolled with SRT nuts (5 tpi screws). Double nut on the X with compression preload instead of tension, single oversized ball preload on the Y, and just the single unmodified nut on the Z. All screws are secured in VXB angluar contact bearings - I couldn't justify the expensive stuff from the big names.

I'm driving the G203V's @ 53VDC from a toroid transformer. The PC is a curbside find - an old Gateway P3 650MHz with 384mb of memory. It's not much but it's enough to run and get the job done. Complex jobs take a while to parse, but run fine.

I moved all the electronics from the X3 column out of the column and into my driver enclosure. No reaching past the column anymore. Hope you all enjoy. Any questions - fire away.

[cjdavis618]

That is very impressive Cadmonkey. You have provided lots of good quality photos of your build as well. Thanks


What size Controller box is that you have on the wall? I haven't been able to find one anywhere near that size for my components. Where did you order/find it?

[cadmonkey]

30x30x8 - Overkill but for the price I couldn't pass it up. Lots of room for future expansion (As I do the Mr. Burns evil genius finger thing and say excellent...) I got it from a local R&D firm that was pitching it because it had a 2" knockout already punched top and bottom and they needed completely sealed units on the top to meet CE requirements. You can't even touch one of these for under $300 and I got it for nothing. A little silicone and a knockout plug and it's good enough for me

Thanks for the compliment. As I find time I'm going to document the mechanical conversion step by step - it really wasn't as hard as I imagined it might be.

[cadmonkey]

I just added another batch of pictures to the album - I noticed there were parts that weren't in the gallery and I didn't have any of the screw grinding pics.

[cadmonkey]

The X3 is singing nicely. With the gibs polished up the X and Y are nice and smooth and I haven't lost a step and right now I'm pushing 30 IPS .001 DOC engraving the Redwings logo in a piece of 6061-T6511 on a .0625" bit - not a lot of cutter forces but going to a final depth of .030" in .001 increments (tonight is the 3rd night) is working nicely. If it weren't smooth and didn't hold position I'd have broken cutters. With the 2.6:1 ratio on the Z screw the head doesn't drop at all over 18 hours and can handle the TIGHT gib setting - it doesn't even shimmy as it moves at rapids (max speed is limited to 30 IPM on Z) - that gib and dovetail still need to be polished but I'll save that for when I install the limits and have to disassemble things again. I have the X and Y limited to 60 ipm right now but am going to test higher speeds later on and see if it can handle it. EMC2 nicely handles the small amount of backlash in my setup (Z is a lot of backlash but that's partly single nut and partly sticktion). All my circles are crispy. Once I get this bad boy done I'll polish it and post pics on my gallery.

I'm so glad I "rolled my own" on this - I learned so much and it's paying it's dividends already. Thanks to everyone here I'm now staying up till 2 in the morning to let a program run...

Greg
www.distinctperspectives.com

[eaglej]

cadmonkey-

Looks great, this is exactly what I hope to do with my X3 once I scrape together all the components ($$$). I saw in your gallery that you commented you may share your 2d prints of all the components you built for the conversion.

I am a design engineer for a living, and I realize how much effort goes into detailing drawings. I would be very grateful if you would be willing to share that print pack- it would save me a lot of time when I get down to it.

I understand if you aren't interested in making them public, but if you are, please drop me a line. Again, great job.

Jason

[cadmonkey]

They WILL be made public - that was my intent from the start. I garned so much information for free on the web I won't hold this back and try and make a profit off them. If I do try for a profit it would be making conversion packs to sell but I haven't made a call on that yet. Now that the machine is CNC they'd be very easy to slap together, but the screws are time consuming. Do enough though and I could upgrade my lathe and be able to go quicker...(sound effects from the Bionic Man echoing in my head...)

The delay will be going back into the models and updating changes made at production time and corrections that I had to make (missing dimensions, hole callouts, that kind of stuff) and an accurate bill of materials. I hope to clean it up by mid July. I'm on vacation right after the 4th and have the cottage to myself so that's my goal is to work on those during the evening hours.

I will state however - I am not, nor do I pretend to be an engineer. I did have a mechanical engineer look over things and make some recommendations of changes as I was designing but I won't guarantee anything.

Thanks for the compliments.

[Crevice Reamer]

Good Job CM! I look forward to the updated plans.

CR.

[MetalBlade]

Looks like a lot of people have gotten the same ideas on retrofitting a better cnc conversion for these X3's at the same time. Your design looks surprising similar to my design as far as the Y-axis goes, except my steppers mount on top and is chain driven so the stepper doesn't stick out so far.

My X mounts are similar to my Y mount. Once I get my production capabilities up to speed, I will be selling mine as a kit that will increase the Y travel to 8'' and X travel to and astounding 30''.

I guess I should also tell you that I applied for my provisional patent a couple of weeks ago. Like you, I wouldn't have done that except for the fact that I'm disabled and can't get a job, so I'm going to have to make my own work. It's just a mater of economical survival you know. I'm all for you posting your designs on the net for people who are capable to manufacture their own to do so; I think it's a great idea. But If I can corner the market on selling mounts that let the ball nut move into the stepper mount, then I hope you understand that it's nothing personal.

Here are some pics of the X and Y base mount so you can see what I’m talking about.

Attachment 61538 Attachment 61539

[cadmonkey]

Interesting! I knew my Y was going to be that way - I never considered doing the same theory with the X. Good thought - and patent away. My goal is in areas other than this so I don't plan to sell parts for conversions, it just popped out there I guess. The difference of my Y from what you've got posted is it's a 3 part piece so there's less stock to remove. Still, it had to be as thick as the mounting ear for the top and sides. The Y barely moves the nut into the standoff, I forget how many inches I get on the Y. X is just 2 or 3" more than stock.

Good luck!

Greg Michalski

[MetalBlade]

Interesting! I knew my Y was going to be that way - I never considered doing the same theory with the X. Good thought - and patent away. My goal is in areas other than this so I don't plan to sell parts for conversions, it just popped out there I guess. The difference of my Y from what you've got posted is it's a 3 part piece so there's less stock to remove. Still, it had to be as thick as the mounting ear for the top and sides. The Y barely moves the nut into the standoff, I forget how many inches I get on the Y. X is just 2 or 3" more than stock.

Good luck!

Greg Michalski

I have to hand it to you Cadmonkey; you’re a smart guy. I'm sure your other ideas are great, and you will have no trouble achieving you next goal. I've been casting parts to get around cutting it into multiple peaces. Solid cast parts will make for a fast and strong product.

[Crevice Reamer]

....that will increase the Y travel to 8'' and X travel to and astounding 30''.

Hi MetalBlade. Welcome to the Zone!

OK, I'll bite. How do you get 30 inches of travel with a 21" table?

CR.