Aaron,
There are several online web page areas for making your own home CNC
machine. They sell the lead screws, ball screws, motors, steppers (or
servos), and control circuts. Some even sell shareware computer software!
It is still expensive when all and done, probably on the terms of $2500 for
a machine capable of making wings with some accuracy.
The most expensive part is the table to mount it to. The accuracy of
the "bed" or table is critical to the accuracy of hte machine. A warp in
the table means a warp in the machine travel. That sucks, trust me. Lead
screws and ball screws costs vary widely baqsed on the quality. Good screws
can run you $10,000, while passable ones could be found as cheap as $100.
Wide range. The spindle (the cutter motor) is also critical as any play
there means lack of accuracy. They can run pretty expensive as well, and NO
your home router is not going to do the job.
Accuracy - I would say accuracy to .005 is about the best you can do at
home. Probably only .01 to be honest. The accuracy though is not as
important as the repeatable results of complex shapes. That is the best
reason to do a CNC mold compared to a bagged plug. Curved surfaces can't be
cut by a wire :)
The # of axises is generally 3. You have the x and y travel and the Z
travel for depth. That is sufficient to do what you are looking for and
more. 5 axis cutters (wher the spindle head can rotate in 3 dimentions) is
not really necessary for wing molds.
BUT saying all this, unless you are making a complex shape/planform, try
starting with a bagged "plug". Make a really nice wing with some extra FG
on the skin. No external holes. Then make molds from that. You would be
amazed at the number of commercial wings that are made that way! I could
name them, but I don't want to piss the mfgrs off. But this is not an
inferior way of doing things. All that it means is that super complex
shapes and super ciritical accuracy is not easially obtained and repeated.
Jason Werner
----- Original Message -----
From: "Aaron Coffey" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, September 28, 2000 9:17 AM
Subject: [RCSE] molds and CNC router requirements
> As mold-making seems to be one of the current threads, I have a few
> questions regarding CNC routers for making molds that, for the sake of
> curiousity, I would appreciate answers to if anyone knows... please!
Please
> assume, correctly, that I know very little.
>
> Is a 3 or 5 axis CNC router used to mill wing molds?
> What is considered acceptable accuracy in the mold? .5, 1, 1.5, or 2
> thousandths of an inch?
> Are there any sites dealing with making a router?
>
> I know of a few places detailing the making of CNC foam cutters, but none
> for a router. For a router, the some points that elude me are a source for
> the software and selection of a spindle motor. The cheapest suitable
> commercial router I have found is a 3-axis one by www.easycut.com, at
> $10,000.
>
> Basically, I wish I was one of those people whose job gives them access to
> such nifty equipment... *sigh*
>
> Thank you for your time,
>
> Aaron
>
>
>
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