Need some help with a project forming brass (maybe)

[Aaron_W]

I build models of trucks and fire apparatus, and that is what really led me here. Lots of things an be made on a lathe and mill that are not available as model parts.

One of the things I really want to make is wheels, in particular tiny replicas of the Firestone "widow maker" split rims widely used on commercial trucks from the 1950s through the early 1970s. I'm working in 1/25 scale so the complete wheel will be less than 1" in diameter.




I've been going around and around in my head trying to figure out how best to do that. I thought about splitting the rim to do the center part and then flip it to hollow out the back. Then form the rim section as one or two separate pieces. I think that would work but seems kind of tricky, takes lots of steps and would be easy to ruin the that center disc.

Then it hit me, instead of doing the center as a turned piece of brass or aluminum, what if I made a pair stamping dies? I could make a matching set shaped like the center disc, one convex and one concave. Then I would just need a disk of thin brass, put the two together and then schmoosh them together forming the center disk. I could drill the appropriate holes in the disk while flat, and even make a matching nipple in the dies that would go through the center hub hole to keep everything lined up.

It seems like this would solve many problems, the more time consuming machining of the dies would be a one time job (per size anyway). Once completed making additional center disks would be pretty quick, and best of all it would provide a relatively true to scale thickness. I'm thinking 0.02" brass which would be about 1/2" in scale vs what is probably closer to 1/4" in real life, but far closer to size than I think would be practical for me to reliably machine.

I would still have to make rims, but those seem like a fairly simple process (its a ring) and I could even cast those in resin once I do the first set.


Does this seem reasonable, if so any tips for stamping thin metal.

Should I use steel for the dies, or will aluminum be adequate?

Wack them with a hammer or should I be looking into a small hydraulic press?

 

[Ulma Doctor]

sounds like you have a decent plan going!
aluminum will not offer much of a service life, but i imagine it could be employed for short runs.
they may be able to be punched out with a hammer, i'd consider that first then goto the hydraulic press if necessary
i'd love to see pictures of the process

 

[Aaron_W]

Thanks, never done anything like that. I kept going over ideas in my head of how to make these and then hit on that one. It offers a huge advantage if it works, I could probably turn out a set of wheels in less than an hour if I did the centers of formed brass and then made one set of rims and used them as masters to cast the rest in resin.

I was thinking aluminum wouldn't hold up long term. Been looking at youtube for ideas. Most are related to industrial tool and die, more educational how its made, than DIY, but still interesting. I'm sure there is one out there, everything is on youtube.

 

[dlane]

Just two or a bunch, ? bet ya someone here with CNC could do ihem if a bunch.

 

[Moper361]

I like your thought process and a good idea .From what ive experienced with those rims the way you plan to do it would pretty much be how they were made in real life the centres would have been pressed out with a die .Also on the original rims the centre is then slid into the rim and then rivited or welded in place .

 

[markba633csi]

Why did they call them "widowmaker"? What's so dangerous about them compared to other wheels?
Mark

 

[Moper361]

Why did they call them "widowmaker"? What's so dangerous about them compared to other wheels?
Mark

They were a split rim and back then when inflating tires they never used cages .When inflating if the ring was not installed correctly or damaged once tbe tire gained pressure the ring could dislodge from its position in the rim .Usually the person would be standing in firing line of said ring and at 80 to 90 psi the outcome was not so pretty or fortunate

 

[Aaron_W]

Just two or a bunch, ? bet ya someone here with CNC could do ihem if a bunch.

The plan is to make one set of dies that will then be able to crank out as many of the center disks as I desire. I would think steel forming brass should last a long time. If this works out as I hope I will do other sizes and styles.

I like your thought process and a good idea .From what ive experienced with those rims the way you plan to do it would pretty much be how they were made in real life the centres would have been pressed out with a die .Also on the original rims the centre is then slid into the rim and then rivited or welded in place .

I thought of that and like the idea that they will not only be easier to do this way, but also more authentic.

Why did they call them "widowmaker"? What's so dangerous about them compared to other wheels?
Mark

Yes what Mopar said. Regular split rims can be dangerous if installed incorrectly or when damaged / poorly maintained. The Firestone RH5s in particular were a bad design with a very low tolerance for error or mistreatment. They were also very popular being offered standard on many Ford and GM heavy trucks. The bad reputation split rims have earned are largely due to this particular style of wheel.

Old OSHA video

 

[markba633csi]

Wow. I'll think about that now every time I need to put air in my tires LOL
M

 

[derf]

Thin brass......I would try to spin them like pots and pans are made. You could make the form from hardwood.