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pauljoels
05-10-2009, 12:43 PM
After the recent discussion on delft clay casting it has made me curious to look into it. My main question is about the type of torches which can be used to melt the metal suitably for pouring from the crucible. I currently only have a micro torch that I use for everything I do, and wondered if this is suitable for melting metal quantities for smaller castings? If not, would something like a blow torch from a hardware store suffice? I just don't have the space for the larger one typically used, and have to pack everything up once I'm done playing.

Also, I know Jason just purchased the clay and rings, but was curious to know if it is worth buying the kit with the DVD? I've seen all the vids on Youtube, and a few others, and it really seems simple enough in theory - does the DVD cover anything more advanced than simple designs? If not, I think I will be taking Jasons route.

Any advice much appreciated!

agent_44
05-10-2009, 02:08 PM
I just bought the clay and an aluminium ring. I found plenty of resources on line, like YouTube that gave me the process from start to finish, and any queries I had were answered as best as they could be on here. I'll probably look up more info abou tit before I give it ago, but I didn;t really see the need for the DVD based on what I have found out already.

Coco
05-10-2009, 05:56 PM
But can ye use a micro torch for melting or do you need a bigger one?

pauljoels
05-10-2009, 06:02 PM
Thanks Lucinda - that was what I thought. I was just wondering if anyone who had the DVD had watched it, because if it details how to do more detailed castings I might be interested - all the ones on I've found on the web seem to be about casting quite basic shapes.

And yes - Anyone who has experience with melting can you get away with a micro torch, or will it not sustain a high enough level of heat whilst melting and pouring? If you can, or if you can use a diy home blowtorch (I think screwfix and B&Q have some that heat to 1500-1700 degrees C relatively cheaply), and my guess is these may be a good halfway house.

Lisa Quinn
05-10-2009, 08:36 PM
I tried using my microtorch to melt the silver and it was awful, I couldn't keep all of the silver molten ( I've had it two years though so it may just be wearing out ! ) So I bought the max flame hand torch from Cooksons (hurrah for freepost!!)(Product Code: 999 955B ) which has a max temperature of 2450 degrees with an adjustable flame and does the job perfectly adequately.

Be sure to let us know how you get on Paul, it took me all week to get the hang of this and there is still room for improvement!

Lindyloo
05-10-2009, 08:53 PM
There have been other posts on this topic. I think it might have been titled melting scrap. And George said there that the DIY store torches are fine to use. They reach the same temperature as the one at Cooksons. Would be interested to know how you get on if you get a DIY store one Paul.

agent_44
05-10-2009, 09:51 PM
When I give the casting a go, I'll be doing it with a DIY store torch. A 'proper' torch is on my list but a way off yet!

pauljoels
05-10-2009, 09:53 PM
There have been other posts on this topic. I think it might have been titled melting scrap. And George said there that the DIY store torches are fine to use. They reach the same temperature as the one at Cooksons. Would be interested to know how you get on if you get a DIY store one Paul.

Thank you Linda - I didn't realise it had already been covered. In case anyone else wants to refer to that thread it's here (http://www.cooksongold.com/forum/jewellery-advice/693-any-handheld-torches-available-melt.html).

I think I'll first give it a go with my existing torch, but suspect it isn't quite powerful enough to melt the quantities I will need for casting bearing in mind the extra needed for sprues etc.

pauljoels
05-10-2009, 09:54 PM
When I give the casting a go, I'll be doing it with a DIY store torch. A 'proper' torch is on my list but a way off yet!

Do you know which one you'll be using?

Polly
06-10-2009, 08:18 AM
Hi Paul

I've used the Taymar T1750 bought from Homebase and it has been fine, it was just the job for me!

;)

I'd love to know how you get on, cheers

agent_44
06-10-2009, 09:48 AM
Do you know which one you'll be using?

It's a GoSystem Tech Multi Torch MT2055 which I bought a few years back from B & Q. I think it should do the job for the amount I want to melt, but obviously I'll have to rethink if not!

pauljoels
06-10-2009, 06:42 PM
Thanks for the advice! I will be paying a visit to the DIY shops one evening this week to peruse the blow-torches.

Di Sandland
06-10-2009, 07:27 PM
roxy rotherburgers

Sounds like an aging showgirl!

pauljoels
06-10-2009, 07:38 PM
Sounds like an aging showgirl!

This is true, but can she have one of Boo's antiquesexchanges (http://www.cooksongold.com/forum/how-market-my-jewellery/1059-starting-up-small-online-business-4.html#post16416)?


Thanks Jason, but am I right in thinking that is a bigger setup that I'll struggle to play with indoors? I can imagine my OH telling me off for it now! I don't have a workbench or anthing, and do most of my work on our dining table or coffee table!

pauljoels
06-10-2009, 07:42 PM
In that case I'm not sure it's wise to look into the Oxy/propane! I have worse visions of what Hannah would say/do to me!

Di Sandland
06-10-2009, 07:44 PM
You're obviously not ready yet for ole Roxy - especially with her antiquesexchange :rofl:

pauljoels
06-10-2009, 07:49 PM
:giggle:s and hopes I'll be ready one day - she sounds super!

agent_44
06-10-2009, 08:27 PM
Paul,

It is the same principle with delft whether casting a simple item or something incredibly intricate. I have had no problems and just watched the videos on youtube. It is certainly cheaper than buying the kit just buying rings and clay.

As for handheld torches I have never had any luck with any of them, the ones I have used do smelt the ore eventually but I have never been able to cast as it simply doesn't get fluid enough to fill the mould. If you want decent results I would recommend investing in some sort of oxy/propane rig which will give you enough oomph to pour in under 2 minutes.

Also the handheld torches are rather dirty, the silver in the scorifier always seems to soot up. You have none of this with oxy propane. You can pick up roxy rotherburgers relatively cheaply if you shop around.

Thats *not* what I wanted to hear Jason, lol! Will any Oxy Propane torch do? I was of the impression you could get torches with different sized tips, which I would be interested in if I was to get one. Trouble is when I look on cooksons or anywhere else, I just see a load of bits and no explanation, and I basically don't know what I am doing. Not that I am looking seriously at the moment, my torch has served me well and has certainly done the job so far!

pauljoels
06-10-2009, 08:30 PM
I noticed exactly the same thing Lucinda - I have used a couple whilst on the couple of courses I have done, but I never took note of their setups or anything since I was not interested in them at the time.

Polly
06-10-2009, 08:51 PM
I've used my DIY propane/butane mix torch to smelt gold into simple mould's with no problem. In fact, pretty pleased with the results:)

Coco
09-10-2009, 08:27 PM
So what's the difference between smelting and melting? :dontknow:

pauljoels
09-10-2009, 08:38 PM
1 s! Duh! Actually i'm not 100% myself but I think it's relating to separating the metals, i.e. extracting the silver from the additives (copper?) and similar with gold etc. I might be wrong but that was my understanding.

pauljoels
09-10-2009, 08:42 PM
Just checked on the OED and this is the posh definition:

smelt1

• verb - extract (metal) from its ore by a process involving heating and melting.

Lisa Quinn
23-10-2009, 10:29 AM
Just wondering how everyone got on with the delft clay casting?

pauljoels
23-10-2009, 10:38 AM
I have bought the bits and pieces and ended up buying a butane/propane mix torch from B&Q - it does melt the metal, but takes a while - it says it can reach a temp of 1650 degrees. As for actually casting anything properly yet, I haven't really given it a proper go yet - just too busy... my OH had OFSTED last week so the weekend I got everything I was roped into going in to her school to help get ready, we went to norfolk coast for the weekend and I've been to Paris with work...I think I'm home this weekend so am planning to play around a bit but no doubt it will end up being busy with other boring things that have to be done (cleaning, shopping etc)...

pauljoels
23-10-2009, 10:53 AM
Incidentally - how long should it take to melt silver - I know there are variables, like how much you are trying, but if someone can give me any tangible indication that would be great, and would let me assess the torch I bought.

Gerry Kaspers
23-10-2009, 12:55 PM
I have done a bit of this type of casting in my class - a small hand torch won't produce enough heat in the flame to get the metal really hot to melting point I would suggest. Normally we use a blowtorch with a wide head to produce a bushy flame. The metal has to be heated till it spins and then the flame held over it while you pour very quickly.

Steady hands and strong nerves required and molten metal very dangerous if lands on you!

Gerry

ps_bond
23-10-2009, 02:19 PM
A lot of the canister torches suffer from flaring until they've warmed up; I wouldn't tip either of my Bernzomatics until they had run for a minute or two.

Sievert's easier though, just fractionally less portable.

pauljoels
23-10-2009, 02:25 PM
When I read the instructions (which I rarely do), it did say to leave it on for a minute on a stable surface for at least one minute - just like you suggest Peter. When I've done this it hasn't flared at all (yet).

Jason - the couple of times I have used it, although it has taken a while to get there, the silver has rolled as you suggest, so I think it may be ok - just not had enough time to play properly yet.

I cannot really upgrade due to lack of space as well as the safety implications - one day we'll get a bigger house where I can have a room all to myself for all manner of jewellery things!

glen
25-10-2009, 10:00 PM
my torch is evil, i use a cutting torch and it sooner look at a metal then it is melted... evil i tell ye[-X