Brake discs a suitable source of case iron

Hi all,

I need to make some replacement axle boxes for a MW 14xx kit that I am putting together and improving on the way.

The axle boxes are brass as you may know so I want to make some CI ones but finding it difficult to locate 1/2" think CI machines plate or block - I'm being a bit lazy and not wanting to go machining a big chunk of CI down.

Is brake disc material suitable CI for axle boxes ? (assuming I can find a solid disc 1/2" or more thick) ?

ta

Lee

Try College Engineering Supply - they can cut slabs down for you to a bit thicker than 1/2" for some machining allowance. Once I got from them an as-cast slab about 3/4 thick, 8 x 4 with bevelled edges, made as test pieces for CI welding. Once through the scale it machined beautifully. I suspect brake discs will be a different grade, made and heat-treated for toughness, might not be easily machinable.

Most brake discs are ventilated and have been for many years. And are usually work hardened at least on the outside faces so my not be ideal.

John and Lee,

​Brake discs machine nicely, the material is of course good quality. It might be hard to find solid discs now, most are ventilated.

Another source of supply is M-Machine that I can recommend from experience.
www.m-machine-metals.co.uk

Regards
​Brian

Someone [maybe Rik Shaw] mentioned Vauxhall Nova solid brake discs being available very cheaply on ebay.

Sorry ... can't find the relevant thread.

MichaelG.

Vauxhall Nova solid brake discs - eBay item 301833633434 - £7.34 (inc post)

Brake discs? Go to your local automotive trade supplier. Preferably a supplier with someone who has been there a looong time (rest can only cross reference for registration numbers!). Or try a local heavy goods haulier that employs a mechanic for service/repairs.

Most rear discs are non-ventilated, I would guess.

Edited By not done it yet on 13/01/2017 10:40:31

I'v used brake disc CI for piston rings, good stuff. If you can get one(or 2 or 3), get an automotive fly wheel, old truck one are good.

Ian S C

I bought one of the Nova ones linked above for tramming the mill.

Like several other contributors have said, the brake discs i have used machine very well. I mostly use them as sacrificial plates mounted on my faceplate, drilling and tapping holes where needed. I get them for free from a local garage.

Thor

That's great guys and nice and cheap too! Solid discs aren't too difficult to find tbh, but I just wanted to hear opinion on the material

oh and good thought about the flywheel too, although I think many are steel aren't they ?

Are ther many solid brake discs tthat are 1/2" thick?

Could just by a bit of square or rectangular CI bar and slice that up

And don't hit it too hard when riviting them to teh frames

A source of cast iron is the weights used in gym equipment. Comes in a range of sizes for obvious reasons....jf

I tried a cast-iron gym weight to turn a small flywheel but never did succeed in breaking through the skin.

Be careful with cast iron from cheap sources like gym weights and garden furniture as the contain all sorts of crap. New brake discs are a good source of high quality cast iron.

I keep a few solid brake discs around the place, they make good sacrificial jig plates. Easy to work and very stable.

The car flywheels that I have are cast iron, older engines ran a bit slower, so a F/W from an older 4 cylinder engine from a truck, or a tractor is a good one to target, you might have to take off the ring gear.

Ian S C

Thanks all,

I ordered a Nova disc yesterday from ebay and it arrived already. Looks to be perfect with a ground finish to 1/2", well 12.6mm so ready to go! I'll update once on the job

Lee

I have previously seen on this forum, recommendations to use sash weights from windows, albeit there is a particular type (or age) to use.

Ed.