Reprofiling wheels

[Hardwicke]

I've made my first tentative steps towards reprofiling abd making my own wheels. The last wheel construction I did was over 20 years ago, removing the tyres off an Airfix 04 and fitting Gibson tyres. Still awaiting completion of a Branchlines chassis...
Now I've the Scalefour Society form tool I've started on the mountain of old 00 wheels. So far I've reduced the flange on one wheel using a plain tool in the lathe.

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Next I've got to mount the tool in a boat and see how stable it is.

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It's a steep learning curve but I have all the Sid Stubbs articles and the ones in Scalefour News as help.
Once I've mastered the basics I've a Bachmann 04 diesel, Dapol Baby Warship, Hornby 31, Heljan Railbus and Baby Deltic, Britannia Pacific Plasser 07, and a few Sharman wheels to reprofile.
Wish me luck.

[davebradwell]

I recall the Myford "boat" was intended to be used with specially shaped Myford tool bits. There's no chance of using it with a standard square\rectangular bit. It can't be difficult to put some packing under the form tool to get it at centre height, although it's a fiddle. The nicest solution is the toolholder Jeremy shows in his thread - it just depends on how much you want to spend.

DaveB

[Jeremy Suter]

Mike. Well done for getting started.

How did you hold the wheel? You could thin the wheel down a bit before trying the form tool.

For now. Try packing under the form tool to get the right height. It sounds like you have plenty of wheels to have a go at. So try on a set you can afford to loose as a first go.

[Winander]

You could thin the wheel down a bit before trying the form tool.

On the back of the wheel to thin the width of the flange root will reduce the cut required from the form tool. See Jeremy's post viewtopic.php?f=132&t=6350&start=75#p87915

You may also wish to take something off the boss to make the back flat.

[Hardwicke]

Mike. Well done for getting started.

How did you hold the wheel? You could thin the wheel down a bit before trying the form tool.

For now. Try packing under the form tool to get the right height. It sounds like you have plenty of wheels to have a go at. So try on a set you can afford to loose as a first go.

I've got a couple of tools from Germany. I'll take a photo later.

[Hardwicke]

Mike. Well done for getting started.

How did you hold the wheel? You could thin the wheel down a bit before trying the form tool.
.

Here's the collet I have.

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[Jeremy Suter]

Thanks Mike
Looks like a nice little arbour. How do you fit it to the lathe spindle I assume you have taken off the 3 jaw Chuck or used a 4 jaw independent . The picture on the Fohrmann site shows it in a 3 Jaw chuck which is wrong, that will offset the mandrel by what ever variation that chuck is offset by. Self Centring Chuck only means the jaws go in together.

[davebradwell]

Happy New Year all.

On top of other comments, I felt this gadget puts the wheel a long way from the headstock bearing - not good with a form tool especially in small lathes. I also have suspicions about the 2 parts that screw together too, as there's room for movement there without some kind of internal register like a lathe chuck mounting.

DaveB

[Stephan.wintner]

A few moments studying mine, and the instructions at : https://www.fohrmann.com/media/pdf/32/7 ... chtung.pdf
enlightened me. (I read the Deutsch, not the Englisch, to avoid translation errors - but the translation looks fine to me, at a glance.)

The wheel is supposed to be centered by the conical shank on the spindle, with the screwed on bits supplying clamping force only, not centering. 2 different pieces are supplied, but they specifically say these may need to be reworked to clear counterweights, etc, and only show one in use. They also show it clamped in a lathe collet in the instructions, which would be more concentric than a 3 jaw chuck and closer to the bearing, but they don't really discuss that.

It seems like a reasonable approach to me, provided one tightens the knurled nut, then the counternut, without overtightening either - and hence properly centers the wheel on the cone, and keeps it perpendicular. What do others think ? I'm not in a position to measure it (yet), but if either the nut, counternut, or pressure ring are badly out on parallelism/perpendicularity that could be an issue. If the pressure ring does not clamp at a suitable, evenly distributed spot, that could also be an issue. (I have no reason to believe either fault to be the case, from playing with it.)

Stephan

[Hardwicke]

It worked reasonably well as far as I could tell when I took the excess flange off.
I too was a little concerned about the form tool hitting the knuckle. I'll make a spacer.

[Hardwicke]

Though having read the instructions I had the wheel in the wrong place !

[David Knight]

What diameter is the spindle on the device? I’m just wondering if it would fit in a collet on my Taig lathe.

TIA

David

[Hardwicke]

What diameter is the spindle on the device? I’m just wondering if it would fit in a collet on my Taig lathe.

TIA

David

8mm

[David Knight]

What diameter is the spindle on the device? I’m just wondering if it would fit in a collet on my Taig lathe.

TIA

David

8mm

Thank you, that will just fit.

Now to decide whether to buy one or make my own…

Cheers,

David

[Terry Bendall]

Now to decide whether to buy one or make my own…

In the Tips and Tricks thread Jeremy has shown how to make a mandrel which will do the job perfectly well. The bought item that Mike has shown is fine if you want to pay for it but you don't need anything that complicated. It could be argued that if you can't make your own mandrel you shouldn't be trying to reprofile the wheels.

Terry Bendall

[David Knight]

Actually Terry it was Jeremy’s tutorial I was going to use as guidance. I have the raw materials and the time and I used to have the skills, just a matter of bringing them back up to speed I can think of better uses for €63.90.

Cheers,

David

[Terry Bendall]

Actually Terry it was Jeremy’s tutorial I was going to use as guidance. I have the raw materials and the time and I used to have the skills, just a matter of bringing them back up to speed I can think of better uses for €63.90

In my view David, that is the way to go. I could also think of btter things to spend the money on - or even not spend it at all! The only way to learn skills, or refresh them it to make things. There have been lots of skills that I have developed in the last 60 years or so which I have had to come back to after a long period of time and the knowledge very soon comes back.

Terry Bendall

[Hardwicke]

It wasn't €63 when I bought it !
I did make a tool for holding 7mm wheels about 10 or 15 years ago. It was a holder for the cutter that was the problem.

[Hardwicke]

Here's to wheel collet I made years ago for 7mm

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[Hardwicke]

And here was my first attempt at making a form tool. It's too coarse.

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