Newbie- Design Stage Looking for Info

[dsquire]

Originally Posted by RCXPLANES Well I have been busy drawing up what I think is a viable 600mm x 600mm x 100mm cutting area router frame concept. The X and Y axis are fully expandable in future tables. I started out simple but like a lot of CAD projects, with the ability to draw just about anything and import files of available products, the table and motion became a more engineered and machined part table. This seemed to come about as problems were solved. We have a great CNC machine shop in town so I will get the machine parts quoted out this week along with necessary machining of existing available parts. I have two Igus 700 mm "W" linear assemblies so I will need to get quotes on the two remaining linears and the EZ Chain. Here are some pictures of what I have come up with so far. It is not 100% complete but all of the very sticky opperational problems are solved and just a few details need ironing out. Bud

Rcxplanes
I have been checking up on some of your posts and see that you are having some trouble trying to decide what works and what doesn't work. I first caught up with you in the "A different (better) kind of screw" forum. I think what they are doing there is great.

I am going to put you onto another forum that you might be interested in seeing as you are talking about timeing belts. It is "Best belt drive ever! (If I do say so myself)". Here is the link to it. If you haven't seen this have a quick read and look at the video. Mike Everman is one smart cookie in my books.

I have been following different threads on the CNCzone for over 2 years. I have formed several opinions in that time as to what is good and what is not. I was going to build a CNC router myself for cutting wood parts and foam wings and fuselages. It would have been a convertible unit to use x,y, and z for placques and signs. Another setup would have been required for cutting wings with a hot wire. For cutting fuselages it would probably have been 4 axis.

This probably will not happen now due to happenings beyond my control. For control I think that I would have gone with a complete system from Gecko. They may be a bit more expensive but from what I have seen they have always come thru to support their product and customers as if they mattered. Some of the people that tried to buy one piece here and another piece somewhere else ended up spending more money in the long run and still didn't have a good setup.

For framing I was planing on using 8020 aluminum. I did not have any formal plans drawn up but have them in my head.

That will have to do for now. If you have any questions that I can help you with feel free to get back to me.

Cheers

Don

[RCXPLANES]

Hi Don,
Thanks for the support and the link to the belt drive system thread. I will be looking at that next for sure. From what I have read here in CNCZone, I agree that Mike Everman is one of the best thinkers on these forums. Without seeing any problems with the system I have drawn I will read the thread with an open mind.
I agree that the Gekko systems seem to be the best drives going at this time. They are missing a complete package though even though they are very willing to help me succeed.
One option I have been looking at is a complete system from Keling Inc. that has everything for a 270 oz. in,. 3 axis system for $350. Cost isn't the overiding issue here so much as a reliable, complete plug and play system minus software for a first project.
The machining and material estimates for the framwork as drawn just came in today for the prototype. I know it will work very well as drawn but for sure it is over built for the size. The bottom line is the machine work and material supplied from the machine shop for the speciality parts will be expensive at around $3000.00 as drawn with material specified. This puts the prototype at around $4500 - $5000 for a working machine.
I am going to revisit the design and see how I may be able to minimize the materials and machining without sacrificing ridgidity, accuracy and reliability. 0.500" 6061 T6 plate is expensive and more difficult to machine than some other alloys. Some redesign and more FEA time in Solidworks is coming with more realistic goals for a machine of this size.

Thanks,

Bud

[RCXPLANES]

dsquire,
Thanks again for the title to the ServoBelt system thread by Mike Everman. I had a similar system in mind at the begining but my itteration required a moving table as I hadn't thought to make the motors part of the moving apperatus. This also caused some difficulties in the Z axis. For use with stepper motors and having started with XL belt profile, a rack had to be molded or machined for the belt to engage as the XL belt doesnt engage itself well at all. I was also struggling with stepper motor resolution and the rotational to linear motion calcs and required one or more motor reduction steps so I dropped the idea altogether.
The ServoBelt system is definitely something to ponder though. Nice work Mike.

Bud

[rcpilot82]

rcxplanes, what will you be cutting with your router? foam,balsa,light ply? I am a newb also but my router is designed to cut rc "stuff". here is the link if your intrested in what I am doing. http://www.cnczone.com/forums/showthread.php?t=53128 best of luck with your router!!

[RCXPLANES]

Originally Posted by rcpilot82 rcxplanes, what will you be cutting with your router? foam,balsa,light ply? I am a newb also but my router is designed to cut rc "stuff". here is the link if your intrested in what I am doing. http://www.cnczone.com/forums/showthread.php?t=53128 best of luck with your router!!

rcpilot82,
The planed material to be cut with this machine is both soft stuff like wood and foam and some light metalic ali stuff for RC as well as some artisan type work. The wood or foam would be for accurate 3D FG or vacuum form mold bucks that my laser won't do. It's great for 2D stuff but I want more 3D capability. I have a 4 axis hot wire itteration for wing cores on the board as well.
I checked out your machine and I can tell it will serve you well. Unlike yours, I wanted to avoid any welding even at the cost of more machined parts as well as make it a purely belt driven machine. I believe the currently available belts will allow for fairly rapid rough shaping with a slower finish pass that should be plenty accurate.

Bud