quick mouldmaking question

[Raffles]

What stops a fiberglass jacket seperating from a silicon mold?

 

[Reactor drone]

Nothing.


or you could build in keys so that the silicone if physically held in place.Building the jacket over a clay layer on top of the piece allows keys to be built into the jacket so that when the clay layer is replaced with silicone the silicone can be locked into the jacket to prevent slumping and deformation of the casts.

For a simpler part with a wooden mould box routering keyways in to the box will do the same thing.

Another method is to collect excess silicone in an icecube tray and attach the collected silicone bumps to a thixotropic silicone mould before covering with the jacket.

 

[Nwerke]

Nothing.
Another method is to collect excess silicone in an icecube tray and attach the collected silicone bumps to a thixotropic silicone mould before covering with the jacket.

You can even do the same thing with cut up chunks of an old mould. Silicone sticks to itself very well.

 

[ZOMBIEREPELLENT]

if you press cotton batting into the silicone as it dries and lay your fiberglass over it then they will be permanantly be bonded, sometimes this isn't a bad idea, sometimes it is.

 

[Draven]

What stops a fiberglass jacket seperating from a silicon mold?

What stops a support jacket from separating?

If it isn't mixed properly, the fibreglass could still be tacky, so always lubricate the rubber before applying any support jacket.

Spray wax, furniture polish and vaseline are all good things to use.

Also, undercuts that stop the jacket sluipping right off might also cause a problem. Check out for those as a solid casting will not give you any yeald!

Exactly what problem are you having?

Draven