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Unread 29-08-2012, 01:51
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Arrow Re: pic: Delrin Poly Cord Pulleys

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Originally Posted by Mk.32 View Post
So my worst fears as been confirmed, the .6 ID of these pulleys make them to flexible. Under the load of 4 cords there is about an 1/8 of an inch of deflection which makes them very stiff to turn. We are switching to 6061-T6 and with an ID of .66.
If you can, go with a much larger OD and use round hollow tube for the roller material.

1.5" diameter x 0.040" to 0.063" wall thickness aluminum tube works great for polycord rollers.
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Unread 29-08-2012, 01:55
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Re: pic: Delrin Poly Cord Pulleys

Quote:
Originally Posted by artdutra04 View Post
If you can, go with a much larger OD and use round hollow tube for the roller material.

1.5" diameter x 0.040" to 0.063" wall thickness aluminum tube works great for polycord rollers.
Agreed, in the 1.5" range you can find very nice rubber tubing to slide over the Tube to act as grip as well!

Such as McMaster: http://www.mcmaster.com/#87235K34 (comes in black btw )

We used 1.25 OD X .060 wall. It allowed us to press in a FR8 Bearings. So we drove one roller and made the rest dead/pressed in bearings.

-RC
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Unread 29-08-2012, 01:56
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Re: pic: Delrin Poly Cord Pulleys

Quote:
Originally Posted by artdutra04 View Post
If you can, go with a much larger OD and use round hollow tube for the roller material.

1.5" diameter x 0.040" to 0.063" wall thickness aluminum tube works great for polycord rollers.
Yup. We loved it.

If you can drop down to 1.25" 1/16" wall the bores can accept an FR8 bearing too, very convenient.
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Unread 29-08-2012, 09:15
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Re: pic: Delrin Poly Cord Pulleys

If you want to avoid grooves altogether, a plate of finger guides may work. See the bottom-left of this photo:
http://www.chiefdelphi.com/media/photos/37572
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Unread 02-09-2012, 12:52
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Re: pic: Delrin Poly Cord Pulleys

Nice, these look great! I wish I had those. I had to bang those out made out of wood on our homemade lathe. http://www.chiefdelphi.com/forums/sh...Homemade+Lathe
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