Author Topic: MPCNC  (Read 1439 times)

Offline ddmckee54

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« on: October 02, 2017, 08:03:33 PM »
Anybody here built one of these?

I'm seriously thinking about printing this to replace my current CNC router.  My current router was based on a salvaged New Hermes engraver and only has an 8"x10"x2" work area.  It was cheaper for them to buy a new engraver than it would have been to replace the proprietary controller that was fried, so I bought the engraver as salvage.  I'm currently using an old lap-top with a parallel port, a 3 axis stepper controller I got from Stepper-world, and TCNC running in DOS to control the router.  It's a kludge, but it was cheap and it works.  I've got less than $150 invested in this thing, but it's so small.

I'm thinking that a 24"x36"x6" work area should contain just about any part that I'd ever want to make.  If I wanted to make it bigger I'd just need to make new rails, which are 3/4" EMT.  According to the estimated print times on the web-site, it'll only take me about 119 hours to print the required parts.  The controls are Arduino based and it uses a version of the Marlin software that my printer uses.  The biggest problem is that I'll have to start thinking in mm instead of inches since that's what Marlin uses - not that big of a deal.  Between printing the parts and work, it should keep me off the streets and out of trouble for a little while. 


Offline Mike R

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« Reply #1 on: October 04, 2017, 01:23:20 AM »
You can use your existing control setup with the new hardware.  Its probably as robust or more so than what they are offering which is effectively 3D printer electronics and drivers, modular and cheap but limited in output for a larger machine.
Looking at that design, you will probably be disappointed by the lack of rigidity compared to what you have now.  I don't know how fine a detail you do now but the larger machine will not hold nearly the same tolerances as the small New Hermes.
My experience with things like this are that they are a great introduction to the hobby but you either move "up" or or give up from machines like that - they've made too many compromises in terms of cost that the performance just isn't there.  For example - EMT is not known for its straightness. You'll probably waste countless hours chasing the imperceptible curve in each piece you've cut, trying to get the machine to work just right.  This was my experience with a 3D printer of similar design, using much shorter smooth shafts that also had small curvature to them.

Hopefully you can find a youtube video of somebody who has built one, but IMHO that design is too flimsy to be worth 120 hours pf printing, plus assembly etc.