I just finished a machine that I designed and built with my brother. He's a machinist/jig&fixture guy at an aircraft factory. This machine took two months to build on the weekends. I have more information on my website. www.doorbot.net

So far the machine works great. I am having an issue with one of my gekko 202 drives though. It quits periodically and that messes my cuts up pretty badly.

Nice design.
That is exactly what I what to do to my ShopBot, an upright gantry and lower mounted linear bearings.
I hate that the rails on mine are above the table.
Are you running rack and pinion on the X and Y?
Where do I find 120" long linears that are affordable?
I see you didn't use any aluminum in the gantry, why?

Woodcrafter, Why do you hate the rails above the table? I am in the design stage of a 36"x48" router and the above the table rails seems like a good idea.

John

I process sheet goods on my 96 x 48 machine. The tall rails seem to always be in the way. I am really tired of reaching over them to pull parts off the table.
The rails seem to limit the accessibility of the table to only the ends.Besides the greased rails have ruined about a dozen of the screen printed company shirt.
I think the only reason for above the table rails are that they are cheap and easy.

Wes - that is a nice machie. Looks perfect for your mill work.

At those speeds, maybe you are loosing steps ? Geckos are well supported, so maybe they can help.

THanks for the advise! The high rail desigh looks strong and simple to build, but I see what you mean about accessibility. Never even thought about the grease problem!

John

Woodcrafter,

I didn't use any aluminum because of the high cost. I was able to pour a polymer to level out the gantry. Worked great. I have perfect (and I mean perfect) perpendicular on the spindle. When I surface the table I get NO swirl marks or ridges! My brother shot measurements using a K&E transit every 6 inches or so when putting the rails on. That took him a couple of weeks solid. (I only worked weekends since his shop is about 225 miles from me)

Nook sells 118" long linear guides for about 1000.00 per pair.

Yes, I am running rack and pinion on all axis' now. I don't intend to forever though. My design allows me to use a belt drive system in the near future. (hopefully)

Also, you should buy a shop apron and wear it like you do your hearing and dust protection. You will quit buying company shirts by doing this.

Harryn,
The gekko is not losing steps. The red light goes off on that one particular driver and I lose power to the motor. Infant mortality I think. Plus, I have about 600 pounds of cutting force so I don't think I'm losing steps in MDF.

Thanks for the kind comments.

wes,
This is very similar to what I am building, why are you going to the belt driven.


Where did you get the rack and pinion, I already have my rails, but they will be in two seperate rails. We do this at work and it seems ok.

RZBKRAIN,

I got the pinion gears from Mcmaster Carr and the rack from Standard Steel.

www.stdsteel.com
www.mcmaster.com