need help designing this 6'x6'

[generalee]

i would like to build something like this----this would be using 2"x1/8 steel bar and 3" x 3/16 flat x filled with re bar and glass fiber concrete mix x/y 6' x 6' with z 1'x 9" (acme 10 tpi) gantry estimate 130 lb --- for the corners on the guide trucks i would cut half way through the 3/16 flat and bend it to 90 and fill with weld ---i need all the help i can get!!! also great accuracy is not crucial this is for versatile hobby art i would like to upgrade from my home made pink tools to some store bought

[RossMosh]

I would suggest looking around here and stealing everyone's good ideas. I also think you should think about whether you want to engineer the whole system yourself. That means a lot of frustrating evenings troubleshooting. There are some benefits of spending a bit more and getting something that you know will work.

[awerby]

All it needs is some Pepto-Bismol paint. Trying to build your own slides by cobbling together roller-skate wheels in a flimsy bent-metal enclosure, and hoping they will smoothly glide over that constructed rail is just asking for frustration. If it actually rolls at all, it won't be accurate or rigid. That frame isn't heavy-duty enough either (concrete shrinks as it sets, and won't help a bit if you pour it into your tubes), and all the other things that would make it work have yet to be designed.

Like Ross tried to tell you, there are many proven designs out there, which are okay to copy. People have built them and made them work, and some are even selling the plans for reasonable money. Check out the MechMate site for an example: MechMate CNC Router - Build your own with our detailed plans If you really want to pioneer your own unique design, that's fine, but unless you're really good at that, with a well-equipped shop and lots of time and money, odds are you'll end up losing all that time and money, with an unusable pile of junk to show for it.

Building something more modest to start with, from a design that's been shown to work, will teach you a lot about this and put you in a much better position to succeed in building a larger more ambitious machine.

Andrew Werby
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