Wheel tread tapers

If one were to make some uncoupled wheels for a trolley to run on the underside of an RSJ, should one make the treads match the taper of the RSJ
flange, exceed the taper (run on outside of flange) or be less than that or the RSJ (run towards the centre of the flange)?
I'm thinking that they should run on the outside of the flange for stability, but don't know for sure.
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

Cylindrical wheels, with angled axes?
I don't know for sure either.
-- Peter Fairbrother

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I matched the angle when I turned down the wheels of a Harbor Freight trolley to fit into 3" channel. It rolls well enough, hasn't gotten enough use to show any wear pattern yet.
jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
What about a slightly convex profile on the wheel so it will find its own running position?
--
jasonballamy
-------------------------------------------------------------------------------
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Match the taper of the RSJ.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 23 Jan 2011 00:04:58 -0800 (PST), " snipped-for-privacy@ems-fife.co.uk"

Thanks all! I've just ordered the wheels (Parallel, but the right price :). I think I might go for Peter's suggestion and mount them at an angle to suit the RSJ flanges. It might be possible to turn them conical, but it'd mean dismantling and rebuilding them.
Making conical tyres for them would be silly. If I were going to do that, I could have made them compete from the same bar stock. The wheels cost less than my decent bar stock is worth!
Ho Hum. So many things to think about, so little brain to do it with...
Regards Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

I reckon you'll get the best life that way.
I was going to explain why, it's entirely clear in my head, but I've had a few tries at writing it down clearly, and failed miserably.
But thenI have seven botttles of sngle malt in front of me, having a wee tasting ...
:)
-- Peter F
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The wheels should ideally be parallel and mounted at an angle. That means the peripheral speed is the same across the wheel width. However, most I've seem have tapered wheels as it's far easier and the speed error is negligable at the speeds and distances whe're looking at. One point, is the difference between RSJs and universal beams. Most UBs are refered to as RSJs but have parallel flanges. UBs tend to have replaced RSJs these days.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I'm going for parallel wheels, mounted at the same angle as the beam flanges. In this case, it's actually hanging a the end of a UB _from_ an RSJ, so the trolley will only fit one way up!
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

I gave my neighbour 4 old wheel bearings from my AH Sprite, 6207 IIRC, and he used them for an overhead hoist on a RSJ and inclined them to suit the web angle, no problems at all.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Max load of 1.5T and max speed of 9000 rpm, I would hope they're OK. The only problem is keeping the dirt out.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.