Making a vulcanized rubber mold/mould

[DAPPH]

I'm trying to find somewhere that sells approx size 3 x 4 inch pads / sheets of rubber that can be vulcanised in a heated mould around an intricate casting so that I can make wax replicas and do some lost wax casting .

I've spent several hours looking on eBay for a supply source the rubber pads in small ish amounts .... say 14 to 20 sheets/pads at a time . Do any of you guys know what I should be looking for and where ?

Dave

 

[the snooper]

cant you make latex moulds ?

 

[DAPPH]

I'm not sure that they will stay true to the part I'm using as a form when they get hot wax injected in them as the latex is so soft even if it is cast in a bespoke reinforced block

I have some Vinamould rubber , it's a thermo casting material & it melts at 150 to 165 oC which is way above th casting wax melt temp but the block of it that I have feels quite soft even though it is the hardest grade available& so I feel it will compress when a bit of hot wax is injected a mould .

I've found some American stuff called " Castaldo rubber ) that is used in the jewelry industry to replicate an original bespoke made piece of jewelry but the prices for a pound block or a pack of 5 mm strips is astronomically silly for it's only natural rubber with an added sulphur content.

30 years ago I used nearly a pound of it to make moulds for my night school classes in making bespoke gold jewelry and it only cost £ 1.40 ... so there is no way It should be costing about £60 to have a pound of it on my doorstep .

 

[Wendelspanswick]

What is the melting temperature of the wax?

 

[galooph]

I've had pieces of 25mm rubber sheet from http://www.camthorne.co.uk/ before, via their ebay shop. Might be worth dropping them an email.

 

[DAPPH]

What is the melting temperature of the wax?

Not too sure at present but it's likely to be less than boiling point
.
A few years ago I made a lot of RVT(?) silicone moulds to cast some trial sea fishing weight designs I'd come up with . The lead i used ruined the moulds I'd made . Even the ones that did work were one shot wonders for they cracked and distorted with the high hot lead temperatures . I should have tried making a few lost wax forms with these cold poured moulds instead I suppose.
I also discovered that the silicone moulds dry out considerably when you hot cast or leave it unused for a few months .

 

[DAPPH]

I've had pieces of 25mm rubber sheet from http://www.camthorne.co.uk/ before, via their ebay shop. Might be worth dropping them an email.

Thanks Dan , Ive sent them an email asking for their help & expertise etc.

Dave

 

[awemawson]

Goggle Alex Tiranti - he stocks mouldable rubbers, latex's, etc in a whole range of durmometers for all sorts of applications. Base near Reading iirc

Here you go:

http://www.tiranti.co.uk/

 

[DAPPH]

Tanks , email also sent