I might, at some point, build a large CNC machine to cut out flat panels. My goal is to be able to form masters for casting track links. Other objects may follow. I doubt that I would need a tool with a shaft diameter larger than 1/8". I agree that the Dremel might not hold up, but it is cheap enough to try. I won't use MDF. I don't plan to use the "vacuum work holding" biz. I ordered the plans fot the "wood router" from Hobbycnc as a general guideline. The size of the machine will be changed. The materials will be changed. The MDF will be replaced with steel for the base and aluminum for most everything else including the gantry. The method of power transmission might change as well. I suspect that acme lead screws will be specified in the plans. I have a ball screw that would work well for the Z axis as well as a linear bearing to mount the Dremel on. I may also replace the acme screws on the X and Y axes with a timing belt drive. I have also considered linear actuators.
As for overdoing.... No matter the size of the machine, the controls are going to be the same. The most expensive bits are the stepper or servo motors and their drivers and the ball screws (if you use them). The larger the tool (dremel vs. wood router) the larger the stepper or servo motors. The larger the work area, the longer the ball screws. Small is cheap(ish). I figure, if I can get this to work in a small scale, I can build a larger machine later, say 4' x 8' instead of 18" x 18". I can use the same computer and program for sure and perhaps the same machine controls. Paul H. ----- Original Message ----- From: Michael Clark To: rctankcombat@googlegroups.com Sent: Wednesday, December 03, 2008 1:34 PM Subject: [TANKS] Re: Metal Shaping http://www.rockcliffmachine.com/ Rockcliff is another one that has several plans, most are made of MDF and use a Dremel like tool. I'd be worried about the accuracy because my Dremel doesn't seem to be designed for this sort of use. I'm reall close to deciding on the Rockcliff, but if something is worth doing, it is worth overdoing. Plus I think a larger tool would be more handy in the long run for my other wood working projects. The real draw for me is the Mechmate. I'd like to CNC mount my router. Of all the tools I have, it is the only one that truly scares me. It spins at 40,000 RPM, it is loud, heavy, unweildy and at night, it tells me to do things. Bad Things. On Wed, Dec 3, 2008 at 12:26 PM, Paul Hilton <[EMAIL PROTECTED]> wrote: You guys have got me thinking about homebuilt cnc routers. I was thinking about how to build my own track link masters for casting in zinc alloy. At first I thought that I would have to pay through the nose for a "actual" machinist to build them. I had also considered rapid prototyping or 3D printing. I like this idea better! A foot square machine would do fine. Something like this: http://www.hobbycnc.com/ Paul H. ----- Original Message ----- From: Michael Clark To: rctankcombat@googlegroups.com Sent: Saturday, November 29, 2008 3:51 PM Subject: [TANKS] Re: Metal Shaping I've been reading the forums at mechmate and it seems a 5x5 sized unit is very doable. It might be interesting to make a flat pack tank. Sadly, it doesn't look like there is much price difference in the sizes. The big ticket items are the controllers and motors. On Sat, Nov 29, 2008 at 2:33 PM, Paul Hilton <[EMAIL PROTECTED]> wrote: This makes it even more interesting! I hadn't thought of using the router for this purpose. Aluminum molds would work well for resin casting. Aluminum masters could be cut for making molds of high temp silicon for casting in zinc or tin alloys. I suppose a smaller machine could be built........ Paul H. ----- Original Message ----- From: Paul Hilton To: rctankcombat@googlegroups.com Sent: Saturday, November 29, 2008 3:13 PM Subject: [TANKS] Re: Metal Shaping This might be interesting as well. Didn't look at it real close, still it caught my interest. Paul H. ----- Original Message ----- From: Michael Clark To: rctankcombat@googlegroups.com Sent: Friday, November 28, 2008 7:46 PM Subject: [TANKS] Re: Metal Shaping Would you believe they have a Waterjet cutter in our manufacturing department, but they deem making toy tanks as being a waste of resources? Philistines. To get to the point of this resurrection, I've been looking at DIY CNC machines and I have found the Mechmate http://www.mechmate.com Free plans to download. Some weird clauses in the EULA, but the design looks decent, and will be sturdier and more professional looking then other plans that use MDF. On Wed, Apr 30, 2008 at 10:28 AM, Aahz <[EMAIL PROTECTED]> wrote: Michael Clark wrote: > It looks like it is the Backend bit of a CNC machine. You supply the > frontend > > Price seems to be about 12 grand. I wonder if just upgrading to a > laser cutter wouldn't be a better choice. Considering the quantity of parts we might need as a whole I think we would be better served by finding a Tech college nearby and getting them to use their waterjet. For those of you in the Pacific Northwest that would be Vashon Technical. Aahz. --~--~---------~--~----~------------~-------~--~----~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to [EMAIL PROTECTED] Visit the group at http://groups.google.com/group/rctankcombat -~----------~----~----~----~------~----~------~--~---
