Newbie - Plans ?

[gitarre10000]

Hello ,
I have been a woodworker for 10 years and am looking into building a CNC machine. I have a couple books on building a DIY machine , but they are not very specific and really only for the authors specific machine. Does anyone have any plans they would be willing to share? Also looking for additional books , articles , etc.... I am looking at using extruded aluminum for the whole CNC machine and Stepper motors. I was also looking at the Gecko 540 for the BOB and drivers. I would really like to see a few breakdowns of actual machines with parts lists to help me understand different styles. I have seen several different types of linear motion and not sure which is best. I know I want to use lead screws on the machine , no belts. If anyone can help , please let me know.
I Appreciate anyones help.
Thanks

[JD_Mortal]

This is the video series I found, which got me started in my project. Much of the information I knew, but again, much I did not.

Watch all his video's and visit his links.
YouTube - Step 1: Linear Slide Bearings
There are TONS of free plans, but each is specific to the needs of the machine. Have you determined your needs yet?

- Available workspace L/W/H
- Materials desired to mill
- Budget

Followed by... specifics...
- Speed of milling (Get it done: slow, Do it now: medium, Do it yesterday: fast)
- Power of milling (Move it: wimpy, Rip it up: average, Is this butter I am cutting: strong)

Which will determine...
- Structure strength
- Available accuracy (Drive system)
- Motor requirements
- Controller requirements
- Power requirements

Which will result in...
- New-found friends
- Family force-field area
- Excessive floor-scraps
- Higher electric bills
- A collection of CNC nick-knacks
and
- An urge to upgrade to a larger, faster, version 2.0 CNC machine

[JD_Mortal]

For linear setups, you have...
Classic mounted roller bearings on a flat-track or angle-track. (Common DIY use)
"V" bearings on an edge-track, or bar, or square-tube. (Alternative to normal bearings)
Solid or hollow tube-guides mounted on ends, or length-wise on a "T", using linear tube-slides. (Industrial old-style)
Track-slides which have two bearing-channels and linear bearing flat-slides. (Industrial new-style)

For drives you have...
Cable and pulley (Cheapest rope-guide)
Belt and pulley (Special use rope-guide)
Chain and sprocket (Best of rope-guides)
Screw-drive (Common setup)
Ballscrew-drive (Best if budget allows.)
Rack and pinion (Requires strong structure, solid steel mounts.)

I prefer track-slides, but tube-guides are great too. Tube-guides are more expensive, prone to unfixable damage, can bend/sag, expand oddly in all directions. As opposed to track guides, where expansion is nearly undetectable, can't sag on mounted surfaces, can be "fixed" with welding and grinding, and are often cheaper. However, both are out of my specific budget.

As for the drive-system... That ultimately depends on your final desires and demands of your CNC for milling. Ball-screw and cable-pulley have the least resistance. Rack and pinions may require gear-box reduction on the stepper and your maximum force is determined by the machines ability to keep the gears on the track and the track-tooth strength. Belts can get expensive with high loads which requires multiple belts. Chains are prone to stretching-wear and will require multi-layer chains to get more strength. Cables are great, as they can easily be doubled-up for strength without having to upgrade everything. However, they are sensitive to heat-expansion and not good in an environment where the temperature is not constant. Ballscrew is better than screw-drive, if you need low resistance and high speed. Normal screws are great if you need to limit reversing-torque stress, and if you are using high-torque/low-speed setups. The screw will transfer less reverse-torque to the motor, due to the higher friction of the mounting, unlike a ballscrew which will just as easily unscrew as it screws.

[gitarre10000]

Thanks very much ,
I am going to check out the video series now.
Thanks again....

[CNC Lurker]

Originally Posted by gitarre10000 Hello , I am looking at using extruded aluminum for the whole CNC machine and Stepper motors. I was also looking at the Gecko 540 for the BOB and drivers. I would really like to see a few breakdowns of actual machines with parts lists to help me understand different styles. I have seen several different types of linear motion and not sure which is best. I know I want to use lead screws on the machine , no belts. If anyone can help , please let me know. I Appreciate anyones help. Thanks

The buildyourcnc site is what originally got me thinking about building a CNC router. I was going to make one out of MDF or plywood, but I read a few threads where people moved from a wood-built CNC to a metal one because of problems concerning the expansion of the wood. I live in Rockwall, TX, and I'm within a 10 minute drive of Lake Ray Hubbard reservoir so wood expansion was a concern of mine (because of humidity in the air, all my metal tools rusted).

While Googling DIY CNC, I ran upon the Glacial Wanderer website, glacialwanderer original LINK & glacialwanderer upgrade LINK

His build can be found on here too.

All that said, I'm building that version, and you can look at other builds on this link: Links & Build Logs LINK

There is a "Plans and How To's" link on that website as well as this site: FLA100-00 LINK

[JD_Mortal]

MDF is not a great choice for long-term use, however, it is a great "first machine" material. Expansion is limited by painting the material with enamel-based spray-paints. The only critical expansion would be on rail-mounts where expansion would "pinch" or contraction would "gap" your linear-guides.

Metal is not expansion free, and is temperature sensitive... so you have to weigh your options... Which do you have, more temperature fluctuations or humidity fluctuations? I live in Florida, near the coast, we have both here, LOL. (Temperature is less of an issue to MDF, as it is semi-flexible to internal fiber expansion and is also a heat/cold insulator.)

If budget and weight is your concern... then MDF may be your only viable choice, besides birch-wood-ply. Up from that would be structural-beams and supports, and then solid structural aluminum, and then low-grade welding-steel, then high-grade high-carbon steel.

[ger21]

MDF is not a great choice for long-term use.

Sure it is, if built properly and sealed and painted, there's no reason an MDF machine can't last 20 years or more. I started building my machine almost 8 years ago, and it's no different today than the day I painted it. There are probably at least 50 Joe's 2006 builds on here, and I doubt that any have had any issues with the MDF. People replace them with bigger and faster machines, but it's not because the machine's were made of MDF.

[hemsworthlad]

MDF would last about 3 weeks here in UK, probably double if you painted it. . Lol