Thread: refurbishing wagon wheels

Check with a local historical village or museum, some of them run displays and have wheelwrights and blacksmiths doing just that. ie. Highfields Pioneer Village
I think you'll find it is the steel band or rim that tightens the whole structure. They heat up the whole thing so it expands, drop it over the wooden framework, hammer it on, then quench to shrink it (and save the wood from burning). The rim diameter is critical and they have some evil looking kit to expand it where neccessary before final heating.

Good luck!

Thanks Andy, There's not much around in the Mackay area, but I remember a Historical village display on the way into Rockhampton, I will check that out next time I'm down that way.

Expanding the steel ring sounds like it would be the way to do it. I'll have to ponder on that for a while

Andy,
just how hot do you think I would need to get the ring to make it expand sufficiently ? Would I get it hot enough in a bed of coals ? And lastly (for the moment), how much do you think the ring would expand ?

Coal - probably. big fire to get a big enough bed of coals though!

Coefficient of expansion of steel is 2x10 E-5 (ie it increases in length 0.00002m per meter per degree.)

So, those wheels look to be about 1.5m diameter, which give a circumference of about 4.712 meters.

To increase the diameter of the hoop by, lets say 5mm, means you need the circumference to increase to 4.728m - an increase in circumference of 0.016m. Using the length, and the coefficient of expansion, means you need to heat the hoop up to 170 degrees above ambient. Getting 190 degrees C from a bed of coals is no problem!

It's probably out of the question unless you are planning a holiday in Vic, but the Sovereign Hill historical village in Ballarat has a working wheelwrights factory from the late 19th century.

When you go there, they demo all the machines used in the process and contrast how they used to be made by hand.

It's very impressive.

Even if you can't make it in person, maybe you could write to them?

Originally Posted by Stuart.

Coal - probably. big fire to get a big enough bed of coals though!

Coefficient of expansion of steel is 2x10 E-5 (ie it increases in length 0.00002m per meter per degree.)

So, those wheels look to be about 1.5m diameter, which give a circumference of about 4.712 meters.

To increase the diameter of the hoop by, lets say 5mm, means you need the circumference to increase to 4.728m - an increase in circumference of 0.016m. Using the length, and the coefficient of expansion, means you need to heat the hoop up to 170 degrees above ambient. Getting 190 degrees C from a bed of coals is no problem!

Stuart, thanks for the helpful info. From your figures it sounds like around a 16mm increase in dia should be achievable. With that in mind I wonder how much oversize I should make the outside diameter of the wooden circle without running the risk of splitting bits apart

Originally Posted by craigb

It's probably out of the question unless you are planning a holiday in Vic, but the Sovereign Hill historical village in Ballarat has a working wheelwrights factory from the late 19th century.

When you go there, they demo all the machines used in the process and contrast how they used to be made by hand.

It's very impressive.

Even if you can't make it in person, maybe you could write to them?

Craig, I probably cant make the trip down (wish I could though). I have a good mate (also a keen woodworker) who lives about a 1/2 hour from Ballerat. Might be able to get him to wander in one day and ask a few questions and maybe get a contact for me,
Thanks

G'day. My grandfather was a smithy in the Malle, way back inthe early 1900's - made wheels for a living, among all manner of thangs...
My father used to help him, and dad said that they made the steel bands the same size as the outer diameter of the assembled wooden bits. Then heated the band, slipped it over the assembled wheel and doused it in water. The shrinkage apparently compressed the steel band a little and in turn held the spokes etc in place.
BUT worth checking with your local wheel-wright (Under W in the white pages) or maybe Cartwright .
Seriously, I am pretty sure the above is correct, but double check - maybe a smithy search in google?
Jeff

some places were laid out specifically for wheelmaking, dunno if you would call it a wheel well or not; it sloped from the corners down to a central well, no doubt where the hub rested. i think that may have been to set the camber of the wheel before they put the steel tyre on it . There used to be one of those wheelwrights working areas in the stableyards of Newnham Hall here in Launceston. Don't know if it is still there as the College has been there for many years now.

If you look at some wheels, the hub isn't in the same plane as the rim, but parallel to it. Does that make sense?

If it is only for display, why don't you cut the ring with a hack saw assemble your wheel fit the ring with a bandit clamp arrangement, and weld the ring back together. I am sure the finished wheel sitting with the weld at the bottom would never be seen.

Originally Posted by woodsprite

G'day. My grandfather was a smithy in the Malle, ...
My father used to help him, and dad said that they made the steel bands the same size as the outer diameter of the assembled wooden bits. Then heated the band, slipped it over the assembled wheel and doused it in water. The shrinkage apparently compressed the steel band a little and in turn held the spokes etc in place.
Jeff

Thanks Jeff, thats cleared up some foggy thoughts that I was having. The more I thought about making the wooden ring slightly oversize, the more worried I was about having a disaster. It sounds like it should be pretty easy to expand the rim enough if the wooden ring isnt oversize.

Originally Posted by tashammer

some places were laid out specifically for wheelmaking, dunno if you would call it a wheel well or not;
If you look at some wheels, the hub isn't in the same plane as the rim, but parallel to it. Does that make sense?

Tas, clear as mud, mate.
Seriously though, I can see exactly what your talking about. This would offset the wheel rim from the hub slightly, a bit like the rim on your car.
I think I'll try and keep these ones as simple as I can, and centre the rim on the hub. Its a good thought about building something to support the hub during assembly, Thanks

Originally Posted by mjford

If it is only for display, why don't you cut the ring with a hack saw assemble your wheel fit the ring with a bandit clamp arrangement, and weld the ring back together. I am sure the finished wheel sitting with the weld at the bottom would never be seen.

Mj, Thats definitely an option. But i think I'll try heating first, if that fails then I'll have a rethink. I think it would be nice to keep them authentic if I can.

Originally Posted by Ironwood

Stuart, thanks for the helpful info. From your figures it sounds like around a 16mm increase in dia should be achievable. With that in mind I wonder how much oversize I should make the outside diameter of the wooden circle without running the risk of splitting bits apart

Given that the wheel will never be in service, and that the metal that is there will not be overly reliable.

So now, in theory, we need to look at hoop stress. (That is a real term, still used today for anything from why a hotdog splits longitudinally, to pressure vessels, and I imagine it dates back to these sorts of wheels, wine barrel construction etc, where there is a circumferencial hoop taking expansion load.)

However, because we don't actually care how much force the hoop will exert on the wheel, or friction between the wood and the steel band so that it won't slip off while cornering etc, we can look at the much simpler aspect of tension in the hoop, as if it were a simple long rod of steel.

Let's take the steel to have a maximum tensile strength (Ts) of 460MPa, and a Young's Modulus (E) of 200GPa.

Strain = change in length / initial length
Youngs modulus = Tensile strength / Strain

Therefore the maximum change in length (ie circumference) =dL

dL= (Ts x L)/E
dL= (460 x 10^6 x 4.712) / 200 x 10^9
dL= 11mm :eek:

Ie, the material will yield if it is required to try to contract onto a hub that has a circumference that is 11mm oversized.

That isn't disasterous - it will plastically deform, but I certainly would not push it! if you made the wheel even 20mm oversized in circumference, I'd not be betting on the ring surviving. This all sounds quite surprising actually - I was expecting the numbers to give us a lot more room, but them's how they come out.

In other words, you wouldn't want the diameter of the wheel to be much more than 3mm greater than the initial diameter of the hoop!

And that says something about the skills of the wheelwright and the smith.

Originally Posted by Stuart.

In other words, you wouldn't want the diameter of the wheel to be much more than 3mm greater than the initial diameter of the hoop!

Stuart, thanks for going to the trouble to give me all this info, it's much more than I had hoped for.
It could still be some time before I get the chance to tackle the job. when I do, I'll post plenty of pics of the process.

Originally Posted by tashammer

And that says something about the skills of the wheelwright and the smith.

Your not wrong there. Lets hope the skills and knowledge of this and other old and forgotten trades are not lost altogether.