Crazy idea for Milling using reprap.?

After our art class this morning Midge suggest we walk around the small Town we go to for the class as she wanted to pop up posters for the craft classes she is running..
My eyes lit up like toad of toad hall as I spotted a Model shop. Where i remained for a few hours. Last week I received the little gears from Conrad as suggested by Erik on his blog. I built an extruder but needed a smaller roller bearing which i got in the shop. The gears from Conrad are really for drive coupling. I bought some more in the shop and the drive coupler to try & replace the noisy home brew washer couplers on the RepstrapBertha machine.
Then I noticed some tiny three phase High speed motors used in planes. Looking at a £12 version (they go up to £100) I realized it was rated at 120W with 6k - 9k rpm, its small tiny light fast and seems to be quite powerful with bearings. The armature is stationary the spindle and magnets spin.
I have bought two £12 and £15 with the idea of adding another bearing and a home-made milling tool holder to provide a light weight milling tool for Reprap to hold some thing like the Dremel 107 or 109 engraving cutter.

I haven't a clue if the motor will have enough humph to do the job of milling plastics. This I think is the only area that might be its down fall.?

Then I thought before I go wasting time I would ask if this is a crazy Idea :-O to pursue?

PS Servo motors are just so so tiny now with metal gears as well.
( Iv not been in a pucka model shop for 20/30 years my 4 kids were all girls. ;-( )

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Bodge It [reprap.org]
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BIQ Sanguinololu SD LCD board	BIQ Stepcon	BIQ Opto Endstop
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My rep strap: [repstrapbertha.blogspot.com]

Buy the bits from B&Q pipestrap [diyrepstrap.blogspot.com]
How to Build a Darwin without any Rep Rap Parts [repstrapdarwin.blogspot.com]
Web Site [www.takeaway3dtech.com]

You need a two flute end mill to mill HDPE and a one flute end mill to work with ploypropylene. Talk to Fred at North Bay Technical. I do most of my HDPE milling with a 0.05 inch two flute end mill with a 3/8ths inch cutting depth.

[www.northbaytechnical.com]

They cost about $10-12 which isn't that much more than Dremel stuff and are made of carbide which lasts and lasts.

I bought and tried virtually everything that Dremel makes in the way of cutter heads. None of it was suitable. Once I started buying from North Bay, I've never looked back. :-)

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Hell, there are no rules here - we're trying to accomplish something.

Opportunity is missed by most people because it is dressed in overalls and looks like work.

Thomas A. Edison

... Forrest, you should try to find something cheaper - i ordered my last set of 10 pcs. 1.5mm-two flute endmill for 35 Euros (or 3.5 Euros per bit) incl. Vat and shipping!

Viktor

Do you think that this kind of motor would work though?
Enough torque to cut I have not played with electric plane motors till now in the day it was glow plug engines.
I will get two flute cutters though is this due to 4 flute melting the plastic..?

These ones seem to fit your spec :-

[www.arceurotrade.co.uk]

They have carbide 3 flute as well :-

[www.arceurotrade.co.uk]

[www.arceurotrade.co.uk]

[www.arceurotrade.co.uk]

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Bodge It [reprap.org]
=======================================

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BIQ Sanguinololu SD LCD board	BIQ Stepcon	BIQ Opto Endstop
BIQ Heater Block PCB	BIQ Extruder Peek clamp replacement	BIQ Huxley Seedling
BIQ Sanguinololu mounting	BIQ standalone Sanguinololu or Ramps mounting	Print It Stick It Cut it

My rep strap: [repstrapbertha.blogspot.com]

Buy the bits from B&Q pipestrap [diyrepstrap.blogspot.com]
How to Build a Darwin without any Rep Rap Parts [repstrapdarwin.blogspot.com]
Web Site [www.takeaway3dtech.com]

Mills and lathes use very high quality motors generally. The cheap motors you see on fans, in cheap construction tools are garbage. But the BIG thing is the collets and bearings you use. You need very very little to 0 play. You'll find things like household drills and dremels have a shocking amount of play. It MAY not matter though for plastic repraps as minor temperature fluctuations probably cause more dimenisonal instability than that.

cdreid Wrote:
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> You'll find
> things like .... dremels have a
> shocking amount of play.
>

I think you will find Dremels are regularly used to mill printed circuit boards.

[northbaytechnical.com]

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Hell, there are no rules here - we're trying to accomplish something.

Opportunity is missed by most people because it is dressed in overalls and looks like work.

Thomas A. Edison