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rjo_
09-01-2007, 12:45 PM
I find Beau's and Graham's recent contribution... both interesting and just plain fun.
I have some long term interests that might or might not involve winding tiny coils, but I have been entertaining myself kludging together a
little machine, using a couple of Parallax servo's.

The servo's aren't the problem...the coding isn't a problem. My problem is finding tiny little tracks and various other small parts.
I'm in the middle of no-where and everything I find on the web is either for serious machining and very pricey.

What's a good source for cheap micro-mechanical stuff?

Rich

Beau Schwabe
09-01-2007, 02:11 PM
What kind of "tiny little tracks" ? like a train? what scale are you designing in?

For rapid in-hand and cost effective proto typing I would go with a personal CNC machine that can handle wood plastic or even metal.



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Beau Schwabe (mailto:bschwabe@parallax.com)

IC Layout Engineer
Parallax, Inc.

mpark
09-01-2007, 02:38 PM
Small parts? Try www.smallparts.com (http://www.smallparts.com)!

Graham Stabler
09-01-2007, 09:05 PM
Its a little hard to know what it is you need but you might try searching for thk linear on Ebay they often have really tiny linear rails complete with a carriage for sale.

I assume the little machine you refer to is a coil winder, if you are using RC servos then perhaps you don't need this precision. I'd take a trip to the local model shop, they should sell a range of tubes that telescope along with a lot of odd bits that can be used imaginatively. The local hardware store should also have parts than can be used and abused.

Graham

Gavin
09-01-2007, 10:06 PM
Good idea Graham,

I picked up two of these small THK's·on eBay last week for $30.
Also·got some bigger ones·for a small cnc router.

Put the coil on the old hard disk 17 size stepper and use the floppy drive stepper to move the slide.
Wire friction clamp from UHMWPE/Cutting board mounted on the slide.
Winding coils with super fine wire will really test my accelleration curve programming:)

Gavin

rjo_
09-02-2007, 11:06 PM
Thanks for the responses... working on it.

Beau...

Right now I'm trying to kludge something together for $0 plus change, very much in the spirit of my paranormal imager... just dinking around.
Think I might get it done:)

Graham...

We don't have a model shop... we have a hardware store though:)

Interestingly... for a town of 14000... we have two girly joints and a XXX book store. Maybe I picked the wrong hobby.



Rich

Graham Stabler
09-02-2007, 11:20 PM
Gavin said...

Winding coils with super fine wire will really test my accelleration curve programming:)
Gavin


The non CNC winders have a flat metal belt that runs continously between two pulleys horizontally, the wire guide can grab hold of either the upper or lower part of the belt with electromagnets depending on which direction it needs to move, it then just runs between to switches that change over the electromagnets. That's serious acceleration!

Luckily you are moving so little mass and the traverse will never be all that fast that you should be OK with something a little less extreme especially if your spindle is a stepper motor.

Graham

rjo_
09-03-2007, 02:25 AM
Graham,

Exactly... I'm looking at an "all day" winder here:) Plenty of glue holding everything together... just need to figure out my spindle and I'm off to the turtle races.

Rich

Fred Hawkins
09-03-2007, 04:23 AM
Has anyone ever re-purposed a spinning reel to wind coils? Seems cheap to me if it would work.

lrumler
09-04-2007, 09:22 AM
rjo_ said...
Thanks for the responses... working on it.

Interestingly... for a town of 14000... we have two girly joints and a XXX book store. Maybe I picked the wrong hobby.



Rich


2 girly joints, and TWO XXX bookstores. There is the one behind Shell and the other one on the opposite side of 80.

Lucas

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"Integrity without knowledge is weak and useless, and knowledge without integrity is dangerous and dreadful." -Samuel Johnson

rjo_
09-04-2007, 02:58 PM
Lucas,

You are the expert. Now we know why you haven't been spending more time studying SPIN.

(It turns out we have a model shop too... but I'm afraid if I go in it will be a "nude" model shop:)

I just posted a reply in the "Prop II or Prop III" thread with my Netscape... which you used to set up your account...So... it shows up with your Icon... sorry.

By the way, do you speak Swedish? If so, see if you can help with Spielha's question.

(By way of explanation, Lucas and I have started the first Central Illinois Propeller Abuser's Group.)

Fred,

I researched your suggestion... and it turns out that there are toy spinning wheels...on EBAY... for about $6. I'm considering it. My project is down to spindle design... and I'm thinking this would be a good time to figure out how to adapt an itty bitty self-centering chuck to a Parallax servo. I have a couple somewhere..... I'm thinking that if my coil winder fails... I can move on to "the world's slowest CNC micro-lathe."


Rich

Fred Hawkins
09-04-2007, 05:18 PM
Rich,
I've always been partial to Mitchell reels, but those of my youth seem to have acquired the 'vintage' label. Still there are some less than $10. One guy says he got a box full at a garage sale....

Fred

lrumler
09-04-2007, 07:45 PM
rjo_ said...


By the way, do you speak Swedish? If so, see if you can help with Spielha's question.

Rich


Min svensk är mycket begränsad du kapitalist bedra.

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"Integrity without knowledge is weak and useless, and knowledge without integrity is dangerous and dreadful." -Samuel Johnson

Graham Stabler
09-04-2007, 08:36 PM
Rich, he said spinning reels as for fishing though perhaps a spinning wheel would be better.

Spinning reels are unlikely to be of much use.

Graham

rjo_
09-05-2007, 07:01 AM
Graham,

oops... and I miss spelled (sic) Vinculum. I must be slipping.

Great fun though.

Thanks from everyone for your attention to the Forum.

I'm itching to do some stereo vision work on the Prop... I don't suppose you could use your influence to get one of the guys to post some serial camera code?

It sure would be nice to finally get a couple of cameras hooked up.

Thanks again,

Rich