How do you keep 2 motors aligned?

[strangetanks]

So I'm building my router table and a thought suddenly occurred to me.

I'm using 2 motors for my x axis, which run on a chain/sprocket system. Sounds like it should run fine, except...

When the machine isn't running, if I bump one side its going to rack it all out of wack. Its a similar configuration to this one: http://buildyourcnc.com/blackToe4x8.aspx

Am I just being worried for nothing?

[ger21]

Am I just being worried for nothing?

Depends how hard you'll be bumping it. When you power it up, you just home it to square it back up.

[cncsigns]

Originally Posted by strangetanks So I'm building my router table and a thought suddenly occurred to me. I'm using 2 motors for my x axis, which run on a chain/sprocket system. Sounds like it should run fine, except... When the machine isn't running, if I bump one side its going to rack it all out of wack. Its a similar configuration to this one: http://buildyourcnc.com/blackToe4x8.aspx Am I just being worried for nothing?

like ger21 said, it will depend on how you bump it, and to elaborate a little on what ger21 said, most machines will have either a hard stop or use some type of proxy switches, if you are using the hard stop method you will jog your machine to home and then physically move the gantry against your hard stops which are set square to your machine, ( there may be more ways to do this that I am not familiar with )
with the proxy switches if you use mach there is an auto squaring setup, which will align your gantry to the switches so once they are square ( the switches and the off sets in mach to align the gantry) auto squaring will be quite simple and automatic I use the switches and they work great,
and are easy to set up and are relatively cheap...
good luck,
cncsigns

[strangetanks]

Thanks guys! After doing a bunch of research on the subject, I found another guy that solved the problem by using a system of cables and pulleys.

Seeing as how I'm strong in mechanical and electrical stuff and pretty much suck with computers, it sounds like a better solution for me.

Thanks all!

P.S. At some point I'll be building a second generation machine (seems like most folks on here do) and I'll definitely keep the software alignment in mind.

[mlabruyere]

You could also use pulleys on the ends of the screws with a 3/4 wide belt running between them with an didler in the middle to eliminate slack. This'll keep them in alignment.

I just use the switches to align the gantry. I'f I've really tweaked it I turn off the switches and software stops and let the gantry square up against the stops. You'll get some noise but if you don't crash the gantry into them it doesn't hurt and gets every thing nice a square.