cliff1959

Here's a picture so far whether you want to see it or not Hours so far amount to about 650 and everything is made from scrap copper hot water cylinders except the temporary plunger. http://www.iforgeiron.com/forum/images/attach/jpg.gif

Oh, I saw a picture online that showed a bar going through the centre of the workpiece when fitted to the lathe ... more than one way to skin a cat then. Sort of, more by luck than judgement, I heated most pieces just to aid bending so it sort of got annealed. Yes, you described exactly what I did. Just a little bigger than what was required, perhaps 3cms bigger. Unfortunately I'll be in Bristol this coming Saturday but there are others listed so hopefully I can make one of those. If anyone's interested I'll post a picture of what I've built so far?

Thanks for the replies so far. Frosty ... the spinning looks interesting but that would leave me with a hole in the centre of the hemisphere. But it's a technique which looks a lot of fun to have a go at. John ... I'm only a mile away from Cockington so talking to Rex and picking his brains may prove informative. Yes, they do have do be in copper and I intend fixing them using solder, the rest of the Dalek is in copper. Do you mean beating the copper into a hemispherical 'hole'. I have tried this but I found the metal gets very, very thin in the centre although the form was made of concrete ... how would a tree stump be utilised? Would you have to carefully chisel a hemi into it? I had a look at the Westpoint course dates page. Would you require me to book on the course date or just pop in for a few minutes of instruction? Another option I'm looking at is trying to obtain copper hemi's from a ball float manufacturer but this could prove expensive.

Hi newbie in England here, this forum looks like a good place to ask this question. Does anyone know how I can successfully make a 4in (10cm) diameter copper hemisphere?, I need 56 of them for a Dalek I'm making out of old copper hot water cylinders Thanks for any ideas.