wheelshape to run on top of a circular rail?

a pair of circular pipes exists, running in parallel.

I wish to use them as tracks for a small railcar.

where to buy wheels, whose "tread" surface is a semi-circle of the right size to fit over the pipes? very low speeds in this cargo application, friction-caused efficiencies should not be an issue.

Or must they be made up by a shop on a custom order?

Reply to
dances_with_barkadas
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Try doing a Google search for "concave rollers".

Here's one example:

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Reply to
no(SPAM)vasys

Can you use a standard v-groove wheel instead or do you need the full contact area between the two?

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Ed Ruf Lifetime AMA# 344007 ( snipped-for-privacy@EdwardG.Ruf.com)
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Reply to
Ed Ruf (REPLY to E-MAIL IN SIG!)

go to a fence supply store. they sell all sized rollers for gates that are shaped to run on pipe rails.

Don

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Reply to
BigDaddy

Always amazes me that I can think up at least three simple things that I would have included right off to assist in an answer ,rather than a huge long thread, when asking for help in any "original post" asking for aid or information.

Where are you located, roughly?

What size is the existing "rail", and is it straight and level, or curved, or ?????, and what span between centres?

What load capacity?

Used Indoor or out, or both or combined or ????

If it's not a trade secret, why not tell us a bit about the proposed use?

Take care.

Brian Lawson, (former user of numerous different applications) Bothwell, Ontario.

Reply to
Brian Lawson

Got a fun park with a roller coaster ride near you? You might ask where they get their wheels from.

Or try asking at a casters store (yellow pages, "casters".

Cheers Trevor Jones

Reply to
Trevor Jones

[hobby groups deleted] If loads are not excessive, you might consider regular pneumatic wheels and tires, with small canted guide wheels to hold the main wheels on track. Use off the shelf, if you can.

Brian Whatcott Altus OK

Reply to
Brian Whatcott

According to Brian Lawson :

And -- does the wheel need to drive the carriage along the rail, or just roll freely?

My first suggestion in the latter case would be to find pulleys for rope or cable of the same diameter, and use those as wheels.

Enjoy, DoN.

Reply to
DoN. Nichols

I don't recall your saying what size the pipes were. As was mentioned by another poster here, wire rope pulleys are available in that cross-section. Lighter construction of the same type is available in fibrous rope pulleys. Some have integral bearings, others are just bushed.

McMaster-Carr carries them in sizes to accommodate up to 1-1/4" rope.

LLoyd

Reply to
Lloyd E. Sponenburgh

I used to have a horizontal photographic copy bench, and the carriage on it that held the camera ran on a pair of 2" diameter tubular rails. The carriage did NOT have wheels in the ordinary sense, but four sets of triple balls races, each set had its three races at 120 degrees to each other, so the contacting surfaces were the outer surface of the tubes and the flat surface of each outer race, thus they made line contact.

The use of sets of three races surrounding the rails may not be suitable for your purpose, but you could use four PAIRS with the members of a pair set at

120 degrees to each, running on the upper part of the rails . This would give a very low friction running system, better than trying to use wheels with semicircular circumferences, which would have quite high wiping friction where the outer edges of each wheel wipe past the rails. Wheels with outer surfaces like vee pulleys would be better, but still have higher wiping friction than the pure line contacts of the outer surface of standard ball races.

Dave.(uk)

Reply to
Davebt

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