Casting a dome in stages

[simwilli]

Hi I'm going to cast my dome this weekend. Can I cast it in stages or is it best to do it all in one go?

[oblertone]

Are you casting it over a former or freehand ? If over a former I'd tend to go for all at once, if in sections then it doesn't really matter.

[downunderdave]

Mar 2, 2018 20:32:29 GMT simwilli said:

Hi I'm going to cast my dome this weekend. Can I cast it in stages or is it best to do it all in one go?

If you mean a one piece casting laid up over a form then it is better to do it in one go as there is a problem of bonding onto a layer that has already set. 
If you mean casting in a few separate pieces then each piece could be laid up at separate times, avoiding bonding issues, although usually a multi piece casting is also done in one go and then separated on demoulding. Any large casting is prone to cracking due to uneven heating and therefore uneven expansion, hence multi piece castings providing some expansion gaps so the cracks occur where designed.

[simwilli]

Managed to cast the dome in one session today. That was hard work!! I'm Absolutely shattered!!
I tried to do The first layer of homebrew 2 inches thick as recommend but it turned out more like 3 inches thick. Never mind at least its done. Thanks for all the great advice.

Simwilli

[oblertone]

Pictures or it never happened !


Well done on the one-hit method.

[simwilli]

I'm going to leave it for 4 weeks before I add a layer of vermiticulite.

Thanks again for all the advice

Simwilli 

[simwilli]

Removed the fitball and former today and noticed a few places on the inner dome which have not been fully filled with homebrew. Should I fill them or just leave them?

Thanks
Simwilli

[simwilli]