Ariel Owners Motorcycle Club

More lockdown DIY. Bronze castings for the 2" and 1 5/8 " exhaust cooling clamps, or rings, or whatever they are called.
Below you see some pics of the way to make a mould to make a pattern that I use as a former in the casting sand.

First I embedded the rings half way up in plasticine
With a thin sheet metal jacket I cast 1st half .
Construct from yoghurt buckets outer mould support that I cast in plaster .
(the mould on the right is the 8 day clock cover mould)
- here a pic is missing, the plaster moulds you see lower down-

After taking first half from plaster support mould , I removed the plasticine and sculpt the 'flip' side in to desired shape with added casting funnel (the colored bit in the middle).
Put back in plaster support and cast second part, remove model from mould .
The blue color is a paint to prevent the mould material to stick to the plaster while casting.

So now I have two two-part moulds for casting the plastic models that I am going to use to press in the bronze casting sand.
I hear you asking; why not use the original rings for pressing in the sand?
because : The plastic models will have a few features build in to make the shape better to withdraw from the sand.

next time, casting the plastic models.
after that, making the bronze casting moulds
and after that comes the actual bronze casting.
dont hold your breath !

Ehhhh, are you following ?

Vincent, are you allowing for shrinkage

Dave

Hi Dave, atm there has been no shrinkage in these moulds/models.
Shrink in the bronze casting will be minimal, 1 > 2 % and by wiggling the plastic model out of the sandmould the hollow shape gets a tiny bit larger.
Final machining of the centre part -which is the casting funnel now- will make the ring fit the pipe.
If he can do it, I can : https://www.youtube.com/watch?v=jHMn92SAlgY

So you see what you can make with little material, unfortunately he has poured some aluminum over his foot.

Easy really.

Who needs Health and Safety, ventilation, protection from hot liquids, eyewear, gloves, clean material free from oil, grease, sand in the melting pot?

Imagine polishing that up with all the voids and inclusions etc, etc.

Quality part though. Just as well its for a Honda and not a repro-casting for my Ariel..........Oh wait a minute.........