Barrel Vault Oven in WSM

[cannyfradock]

Hello Gream

I normally render over the vermicrete layer the following day....good point...while the vermecrete is still "green" it will make a good "bond" with your waterproof render. (I would still give the vermecrete a lick of either uni-bond or SBR diluted with water at a ratio of 3 parts water to 1 part SBR/uni bond........bad point....the more moisture you trap within the dome the more careful you have to be with your curing fires....piamo, piamo...take your time in curing the oven....start with kindling then gradually build up the heat over a 2 or even 3 week period ending up with a firing as hot as the devil's own festering arsehole.....With that sexy beast of an oven you have built you could push it to 650 (ish) celcius, but you should only need to fire it to 450c then wait half an hour and cook on receding heat at about 370c (ish).....practice makes perfect but it's also lots of fun in the trial and error process of knowing how your oven works.

Brilliant build!!!

Terry

[gream0604]

Hi terry. Thanks for the advice. The vermicrete has been on for about a week now. I'm thinking that i might get the first waterproof coat of render on tomorrow. Whats the best mix for the render? Should I be using lime in the render at all?

Cheers

Matt

[cannyfradock]

Hi Matt

For a waterproof render I would use a normal render mortar of 4 parts sand to 1 part opc cement with waterproofer added in the mixing water with a shovel full of hydrated lime added into the mix. But in all honesty I use K-rend. This is a product used on most "new builds" at the moment as a render finish. It comes in 25KG bags and you just add water. It's flexible and waterproof and comes in about 6 different colours. Most builders merchants stock it....or a similar product. It costs about £15 a bag and you will need 2 or 3 bags. If you google "sheffield Insulation" to find your nearest store.......they sell it to Joe Public at about £12 per bag.

Try to put a 10 or 15mm space between the render and the chimney/vent. This is one area which can give a few probs.

Terry

[gream0604]

Got the first coat of render on, and used some of the leftover patio slabs to finish off the front area.





Showing the opening for the flue


And showing the flue in place. Not fixed in yet!

[gream0604]

Getting there with the oven now, Got the render on and painted, and had a few curing fires. Still got a few little bit to do to finish it off!



Couldn't resist firing it up tonight to try some pizzas, and they came out amazing!! So pleased!



There are a few rather large cracks appearing in the render. There is a bit one from front to back along the top of the oven, and a couple of smaller ones on the side. What is the best way to patch these up?