Pizza oven mold

[keithlmartin]

i have been lurking around forno bravo for over 10 years now with the hopes of one day making my own oven. that time is now come and i feel the cast oven is the one for me.

i am also thinking if im going to make one, why not make more. i have lots of friends... To do so however, requires a mold which in all my searches on here and on the internet, i have not found a detailed process of how to make one.

id prefer a segmented design but at this point, id be happy with a two part mold for the dome and the entrance.

i dont know if it would go against the people of Forno Bravo as i know they are trying to sell ovens however if not, i'd be happy to post my mold build in details so others like me can hopefully find it.

appreciate some help or guidance on this

[david s]

Having been down this road, I’d suggest you first make one for yourself using the sand mould one piece before embarking on building a mould. The time and effort of making moulds is considerable and if not done correctly can place you in a position of having a casting that cannot be removed from its mould. You are then right back to square one. The single piece mould cast in situ method I have detailed will teach you lots, from which you can progress..

[keithlmartin]

Having been down this road, I’d suggest you first make one for yourself using the sand mold one piece before embarking on building a mold. The time and effort of making molds is considerable and if not done correctly can place you in a position of having a casting that cannot be removed from its mold. You are then right back to square one. The single piece mold cast in situ method I have detailed will teach you lots, from which you can progress..

Hey David. I'm very glad you replied as i originally tried to send you this in a pm but the msg i got back was that you have exceeded your private messages.. lol.

so if i cast mine using the sand mold. should i use it to then form my fiberglass molds for future castings?

[david s]

Yes, you could do that, althoughglassing against the underside of the casting will be near on impossible. Try glassing over a gym ball instead. It’s size can be easily altered by how much it’s inflated.
Thanks for alerting me to the PM problem. I thought I’d deleted enough for it to work, maybe not,

[fox]

Making a fiberglass mold is a time consuming and quite a complex job but also quite possible to do if you have the time, the budget and the knowledge.

You have to really think about the interlocking step joints and how the mold will come apart, how to vibrate the refractory and how much money you want to invest in a vibrator.

There could be compromises that might suit some people, certainly making the dome in a one part component would be hugely easier.
Once cast it could be cut into four pieces for portability but, once re assembled the joints would not have any mobility to move like a stepped joint.

Obviously the dome size will make a difference to overall cost, a small dome could be made in two or three components, my first ring mold design worked well for around 10 castings and was fairly easy to build however, any home built design using average tools, will be a big job taking hundreds of hours to complete.

Having said all of that, if you enjoy working with fiberglass, have a decent shed, tools and the desire to succeed then It is very doable.

[w650gb500]

I purchased a 3-piece cast WFO and built it a year or so ago. Here is a link to the thread that I started with pictures for reference.

[jakeanderton]

I purchased a 3-piece cast WFO and built it a year or so ago. Here is a link to the thread that I started with pictures for reference.

"Easy way out" still gets the job done. Nothing to turn your nose up to.

[keithlmartin]

Making a fiberglass mold is a time consuming and quite a complex job but also quite possible to do if you have the time, the budget and the knowledge.

You have to really think about the interlocking step joints and how the mold will come apart, how to vibrate the refractory and how much money you want to invest in a vibrator.

There could be compromises that might suit some people, certainly making the dome in a one part component would be hugely easier.
Once cast it could be cut into four pieces for portability but, once re assembled the joints would not have any mobility to move like a stepped joint.

Obviously the dome size will make a difference to overall cost, a small dome could be made in two or three components, my first ring mold design worked well for around 10 castings and was fairly easy to build however, any home built design using average tools, will be a big job taking hundreds of hours to complete.

Having said all of that, if you enjoy working with fiberglass, have a decent shed, tools and the desire to succeed then It is very doable.

Thank you for the reply. i did see your two molds you made, the one in rings and the other over the exercise ball. wish the one on the ball had a few more photos along the mold making steps..

[Ronstarch]

fox regarding your mold that lasted for about 10 castings, what happened to it after that? Surface no longer smooth enough to release well, cracks/damage?

[fox]

Ronstarch Hi sorry I have not been well for a few months, the mold was badly damaged while trying to remove the 10th casement….. it was a 100% my fault as I was to lazy to wax the mold before the pour, it stuck so badly that I had the use a grinder the get it out!
I have since sold on my business but that old mold has in fact been repaired and I believe it is back in use!