Why no 4 x 8 (or larger) builds?

[Free_Thinker]

Greetings! I am new to the site. I have been bitten by the CNC bug. I ran CNC as a machinist for 7 years and can't believe that owning my own can now be a reality! Exciting! The possibilities are endless!

My question: Why doesn't hardly anyone out there (other than blacktoe) have plans or seem to build CNC's larger than 24" or slightly larger wide? I would like a machine with a 4 x 8 cutting area (since that is standard size of full sheets of plywood) and I would not be limited by almost any project. I understand that bigger means more expensive and larger footprint. I also understand that widening the gantry with materials or frames that are not rigid will cause loss of tollerances, but isn't there a way to overcome this in a somewhat inexpensive manner? Why no plans, discussion, etc.? Am I missing it somewhere or is a 4 x 8 machine just much bigger than most want in their shop?

Any plans, discussions, answers, etc. would be appreciated!

[Phife]

Larger machines cost alot more $$, they require larger motors, thicker, stronger materials for the frame and parts, and expensive linear motion systems. They also take longer to build.

They take up alot of space, so if you only have a small shop or basement then a large machine is out of the question.

I am actually in the design phase of my new machine which will be a 5x10 cutting area, I expect it to cost me around $15-20,000 and I plan on taking about 5-6 months to develop/design it and another 5-6 months to build it.

If you have the time, budget and space then a large machine can be made, but most of us here are short on one of those 3 things, so a compromise is made and a smaller machine results.

[lovebugjunkie]

If I needed and had the room for a 4x8 or bigger I would go with.....

MechMate CNC Router - Build your own with our detailed plans

[dave22]

Most people don't build these large machines mostly for the reasons you stated. But mainly I suppose most designs are driven by need, not necessarily the bigger is better attitude.

That said, for excellent plans and a great support forum for a large 4'x8' CNC router see the Mechmate site at this link.

MechMate CNC Router - Build your own with our detailed plans

Hope this helps

[ger21]

I also understand that widening the gantry with materials or frames that are not rigid will cause loss of tollerances, but isn't there a way to overcome this in a somewhat inexpensive manner?

Not really.

In addition to the Mechmate, a lot of builders of Joes 4x4 machine have enlarged it to 4x8. Welcome to Joe'sCNC.com

[CarveOne]

They're around here but you won't find them based on searches for generic thread titles. Mine is here. It started out as a 49" x 62" machine and got totally out of control. Search YouTube for CarveOneCNC for a recent "walk around" video that shows it. 6-1/2' wide by 12' long with cutting area of 50" x 11' 4". I have seen photos of a 20' long home (or shop) built machine posted on CNC Zone.

The MechMate is very popular. My two nearby CNC buddies just got serial #67 assigned to their 5'x10' joint build.

CarveOne

[Lapin]

I also build a quite big machine that will fit an entire MDF or plywood sheet. U can find it here

[Free_Thinker]

I also build a quite big machine that will fit an entire MDF or plywood sheet. U can find it here

You said you build them...does that mean for yourself or others. If for others, I would be interested in a quote on a machine 4x8 or larger. Must be able to do 3 dimensional.

[lumberjack_jeff]

I built Mech Mate #31.

It can be done without breaking the bank.

http://www.mechmate.com/forums/showthread.php?t=1789

[mlabruyere]

You said you build them...does that mean for yourself or others. If for others, I would be interested in a quote on a machine 4x8 or larger. Must be able to do 3 dimensional.

I think he meant that he built it for himself. I've not seen him note anywhere that he was selling them.

If you want one that's already been thought out and engineered for you go with Joe's Hybrid.

I built mine from steel and 8020 and have a cutting area of 42"x45".

[Lapin]

You said you build them...does that mean for yourself or others. If for others, I would be interested in a quote on a machine 4x8 or larger. Must be able to do 3 dimensional.

No sorry, im not selling plans or anything (yet atleast:P) i just wanted to show a bigger machine. And as the other mention i think a Mechmate or a Joes Hybrid is a good choise if u want a bigger and proven design.

[ahren]

I think another part of the reason few sets of 4 x 8 plans have been available is due to the drive mechanism required for an 8' axis. There really wasn't a viable screw-driven system for an axis this long for the DIY community. Mechmate solved this problem with a rack and pinion drive, but it was really integrated into their system and wasn't generically applicable. This was really the inspiration for the development of our own rack and pinion drives, and I think you'll see quite a few more plans coming out this year as a result of these being available.

Since we started selling them in Oct 2009, they have been hugely popular, and are enabling people (including lots of Joe's builders) to build larger machines. Joe has integrated the drives into his newest set of plans, Fine Line has a 4' x 4' in the works that is easily expandable to 4' x 8', and a newcomer to the game, Schuldt Brothers Automation, is working on both kits and plans using the system. 2011 should be an exciting year for bigger machines and plans.

Ahren
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