Making moulds from wooden/card masters

[admiraldick]

Hi everyone,

i've been making a pueblo recently for games set in the Old West, but its meant making a lot of windows and doors. so i thought this might be the perfect opportunity to get into resin casting. i would only need a few masters and i could recast them as needed.

obviously, one of the best materials for making doors and windows from if wood (matchsticks, coffee stirrers and lolly sticks) but i wasn't sure if those would not cast well. i don't want wast rubber to find out that i won't be able to remove my masters from the mould. i've looked around but not found the answer i was looking for. has anyone had any experience in this area?

[OSHIROmodels]

has anyone had any experience in this area?

All the time 

You just need a good release agent like a spray on wax and a coat of paint goes down well also.

cheers

James

[Zafarelli]

Balsa wood is a pain to demould, but matchsticks and coffee stirrers should work well. As Jim said, seal the wood with something (I use ordinary spray primer), and you're good.

[DD-Chris]

Agree, as has been said, a good coat of ANYTHING will work, i use brush on varnish on the wood myself. but i assume ANYTHING that will get rid of the pores on the wood will work.

[senex]

imo is wood not the best material to prepare masters for mouldmaking.
why not sculpt the doors and windows in putty and mould these sculpted masters?
A door- or window-frame can in most cases made with only two sculpted sides, the other two side are not to be seen (looking to the wall and to the inside of the room).
for this you can make a  one-sided form and cast it with stewalin
windowframes are mostly fixed on the building and must not be very durable themself.
If you are interessted I may look for some pictures.

[Sangennaru]

I make quite often moulds with balsa with no big deals. You can't use the piece after, anyway, because some parts will remain attached to the silicon. Well, once you have the silicon mould you can easily cast a resin copy and keep it as backup master!

here's a fast tutorial about it:
http://www.thelazyforger.com/tutorials/making-moulds/

Balsa wood is a pain to demould, but matchsticks and coffee stirrers should work well. As Jim said, seal the wood with something (I use ordinary spray primer), and you're good.

Matchsticks are nice, but they hardly have the same amount of texture as balsa wood. Even with the prime you will loose detail, i think that losing the original master is not a great deal, afterall ^^

[Hammers]

Card has a tendency to ward so I'd use sheet plastic or plywood or birchwood or some similar hard wood (on a sidenote: funnily enough balsawood is considered a hardwood)

[OSHIROmodels]

Just back the card with plasticard or somesuch 

cheers

James

[admiraldick]

I just wanted to update this thread a little. with massive thanks to everyone who responded, especially Sangennaru (your tutorial, and in fact whole blog, have been really helpful), i poured my first mould this afternoon. its just a tester; some little windows for my mexican pueblo buildings, but its a start.

hopefully, I'll get the time tomorrow to cast up some resins and I'll post some pictures to celebrate my entry into a much wider world of modelling.

I also wanted to say I took some sound advice from Stu at the Tabletop-Terrain blog (again, another really helpful and encouraging blog).

[Sangennaru]

Will follow this with interest. Please keep us updated!