Vermiculite-concrete as roof

[CanuckJim]

CV,

Type S is a cement. Comes in a bag, just like Portland, and it's marked as such. Ditto Type N, which is used for exterior vertical applications because of it's better stickiness. On the hardness scale, Portland is at the top. The other two have more flex. Type S mixed with fine sand (1:3) is standard here for laying block and brick. No reason at all you couldn't use it in your vermic/cement mix.

Jim

[david s]

CVDukes, If you use colouring in your portland cement mixture (we call it oxide colouring here in Aust. ) you will not get a particularly good colour because the grey of the cement tends to kill the colour of the oxide. I find it better to make a "paint " from white portland cement (expensive but you don't need much) lime, finest sand you can find. Mix these in equal parts with some oxide and paint it over your cement render. You get a nice colour intensity. Remember to add the same proportions of oxide if you do subsequent coats.

[Frances]

uh Jeff... what is that picture of your oven doing hiding in this thread???

Give it its own thread mate, and get the advice it deserves!

I'll start off here, because I happen rather to like those swirls. One piece of advice would be to tone down the light/dark contrast a bit. Say if you went over the whole oven with a translucent layer of ochre. Or put medium ochre/brown brush strokes along the edges of the white swirls, to soften them a bit.

Actually, I'll tell you what I'd probably do: add more little swirls on the big ones. Hang on I'll grab a piece of paper and try to show you what I mean. (Watch this space.)

I think the overall design works beautifully, looks really striking on the small picture, but when its enlarged - well, I see what you mean, it does need a little bit more work

At least, thats my opinion....

[chuckster]

I bought powdered dye at Lowes 2 years ago when I built my oven. I used 1/2 of the bag (it came in a box on the outside) to 1 mixer of concrete. It worked OK for the work area next to the oven. It was about $5US if I remember correctly. Its still red two years later.
Chuck

[Dutchoven]

Here in the US also...type S is preferrable for load bearing applications...type N(having more lime) is preferred for vertical applications...repointing, covering, surface bonding
Dutch

Originally Posted by CanuckJim

CV,

Type S is a cement. Comes in a bag, just like Portland, and it's marked as such. Ditto Type N, which is used for exterior vertical applications because of it's better stickiness. On the hardness scale, Portland is at the top. The other two have more flex. Type S mixed with fine sand (1:3) is standard here for laying block and brick. No reason at all you couldn't use it in your vermic/cement mix.

Jim