annealing copper question(s)

[bearcar1]

I need some advice on this process. I understand the whys and hows but in my latest endeavor in making endplates for a boiler project I've become a bit paranoid and am delving into uncharted waters without a good compass. I took the suggestion from another member and obtained the 'flats' out of the drop piece of the boiler tube. The torch that I have is merely the hardware store, screw-on-the-bottle, flame head on a 1lb. cylinder of MAPP gas. Now then. When I opened out (unrolled) the left over piece of pipe, I heated it the best that I could for about 20 minutes on both sides and it seemed to soften the tube up, not as much as I would have liked but it got the job done it seemed. Of course there was ALOT of surface area there that acted as a heat sink so that is understandable. I'm at the point that I have the blanks cut out and turned to size and am once again going for the annealing process. I cannot seem to get the disks to glow a dull red color (at least that I can tell). What's the opinion here, do I need to get some more heat or is it just that I am expecting the piece to glow for a second or two before it losses that color. I just really do not want to have these pieces crack when I form them as I already have quite a bit of time into them as is and have a lot more to go. The disks are .067" thickness and roughly 3.00" in diameter. I've set up a close fitting hearth from fire brick with a closed in top and open front. I've performed the same heating cycles to both sides. I'm going crazy here and need advice from the folks that have been this predicament.

Thanks in advance

BC1
Jim

 

[firebird]

Hi Jim

I'm not sure about mapp gas? I'm sure somebody will jump in soon and tell you. I use a propane bottle and torch which heats up copper no problem.

Cheers

Rich

 

[Blogwitch]

Jim,

You really need to hold it at cherry red heat (a bright orangey colour) for say at least a minute or two, then you can either let it air cool or drop it into a bucket of cold water, the plate will be soft no matter which method you use. You might need to do this a few times while beating over the edges, you will soon feel it when it starts to harden up again.

There is nothing stopping you doing it in the kitchen (except maybe the better half) and use the stove for the main background heat, using your torch to play over the plate to make sure it is evenly heated through. Or maybe get your barbecue going and bury the plates amongst the charcoal. Just use your imagination and use what you have available.

You really are going to struggle to get and keep it up to annealing temperature with the small torch you have.


John

 

[bearcar1]

Thank you Rich and John for your replies. Turns out that my wife is at work and I was considering the BBQ but thought, what the heck, the good Lord hates a coward and I cleared off one of the front burners on the range and had a go. Put the torch on it for a few minutes and it glowed like a newlywed. I kept it at that color for several minutes and now feel confident enough that it got hot enough. I really do not like using this method and would not suggest it to anyone else but it does work. I had the fire extinguisher at ready in case of any problem. I think that I will try the second piece on the BBQ and see what happens there, at least I won't be in her space should something go wrong. :hDe:

BC1
Jim

 

[Gedeon Spilett]

Hi
you have to stay in subdued light to easily see the red color of the heated metal (the orange color of carrot actually in dim light).
but if you have difficulties to heat your end plate to red, the silver brazing of the boiler looks not doable with your torch.
cheers

 

[Entropy455]

http://www.harborfreight.com/propane-torch-91033.html

Take a look at the above link.

This torch will pump out about 500,000 BTU per hour, which is equal to about 146 kW, or 196 horsepower.

I own this very torch, and I use it often for preheating metals for welding. I occasionally melt small batches of aluminum with it.

The price is hard to beat.

 

[Entropy455]

Also - this torch instantly starts campfires. It will even get wet wood burning. . . .

 

[Blogwitch]

Jim,

Glad it worked for you, even though you didn't like doing it that way.

But it did prove that there are more than one way to skin a cat if you put your mind to it.

I was once on a stand at a steam rally and the chap on the next stand was displaying some of his larger ic engines. All his aluminium casting was done in the garden using an old stainless kettle with the ali being melted on a large open pit fire. He said it was better than his gas smelting plant because he could get larger quantities melted to do larger castings, it took time, be he said that as long as you have patience, almost anything like that can be done over an open flame.

For larger jobs I use burners like Entropy has shown, but with a larger range of smaller nozzles. Stew and myself easily got his 3.5" boiler up to silver soldering temperature in a few minutes with a couple of those.

Like these

http://www.machinemart.co.uk/shop/product/details/fs560-gas-torch-kit?da=1&TC=SRC-propane gas torch


Well done on keeping out of the way of SWMBO


John

 

[bearcar1]

Now that I have a it of a 'feel' for what to look for in terms of heat etc., I agree that the set up I have wont have enough oomph to cut the cheese. ;D I am going to look for a torch setup like what you directed me towards John as I am not going to need something that will start a forest fire in a rainstorm but something a bit more moderate. Tomorrow, or most likely this weekend will be set towards making up a set of punch and die blocks from the brown stuff much like Firebird (Rich) did in his "a small boiler" build thread. I just like the idea of not having to beat the daylights out of these pieces with a mallet although that would work just as well. Like John says, there are more than one way to accomplish ones goals if one takes the time to think about it. :bow:

BC1
Jim

 

[steamboatmodel]

There are times when "having to beat the daylights out of these pieces with a mallet" can be very therapeutic, there are other times when pressing them out with a die and having them all come out the same is equally satisfying.
Regards,
Gerald.

 

[Mainer]

I think you may be overheating the copper, which will adversely affect its properties. Dull red, seen in subdued light, should be sufficient, and I don't believe there is any point to holding it at that temperature longer than it takes to be sure the material is at temperature all the way through.

Copper work-hardens fairly rapidly, so if you are doing a large or complex bend you may need to anneal more than once.

 

[kwoodhands]

First thing, get the copper off the fire brick.It absorbs the heat instead of reflecting it.
If you lay the copper on insulating brick you may be able to heat the copper to orange color.Then it is annealed.
I bought six or eight bricks from the "Pottery Barn".Cost about $25.00 or so if I recall.
You probably need a bigger torch, I use a Victor propane torch that hooks up to a standard barbecue propane tank.
I tried to buy the insulating bricks locally,no luck.The pottery Barn shipped the bricks in a couple of days. You will be amazed at the difference between fire brick and insulating brick.
For now ,try placing the copper on the edges of the firebrick.Then most of the copper will be in between the brick.Then play the torch at one end til it gets orange.This will take some time because the entire piece must heat up.
You might be able to go faster on a charcoal bed to heat the copper as you heat up the top.
mike

 

[bearcar1]

There are times when "having to beat the daylights out of these pieces with a mallet" can be very therapeutic, there are other times when pressing them out with a die and having them all come out the same is equally satisfying.
Regards,
Gerald.

I wouldn't want to waste a good throttling on these pieces, that is what I have old what's her name for. ;D But constable, I was just attempting to make some boiler plates........ honest.

Mike, I will have a look and see if I can find some of those insulating blocs you speak of. -I had the pieces setting on top of a small copper trivet while heating.

BC1
Jim

 

[ref1ection]

After looking at the kit suggested by Bogs I thought it was a good setup and emailed to enquire about shipping to Canada. In the reply I was informed that they don't ship to North America. After quite a bit of searching I thought I'd found what I wanted only to be disappointed. Can anyone suggest a supplier in Canada or the U.S. with a similar torch setup for reasonable money?

Ray

 

[woodnut]

Have you tried Princess Auto?

www.princessauto.com

John

 

[ref1ection]

Thanks, I tried princess auto but no luck.

Ray

 

[Chazz]

This one is 100,000BTUs http://www.plumbersurplus.com/Prod/...C-Weed-Dragon-Garden-Torch-Kit/208093/Cat/797 .

Cheers,
Chazz

 

[steamboatmodel]

After looking at the kit suggested by Bogs I thought it was a good setup and emailed to enquire about shipping to Canada. In the reply I was informed that they don't ship to North America. After quite a bit of searching I thought I'd found what I wanted only to be disappointed. Can anyone suggest a supplier in Canada or the U.S. with a similar torch setup for reasonable money?

Ray

Have you tried a local welding supplies shop? One recomendation I picked up was for this combenation
#3488 Sievert Pro88 Handle
#3509 Sievert 7" necktube#3062-93 Sievert Regulator
#1510IS Sievert 10' hoseNozzle 1.38" Power Burner - (148,000 btu/hour) - silver brazing
#2941-02 Sievert Nozzle 1.1" Standard Burner (26,300 btu/hour)
#3940-02 Sievert Nozzle 17MM Standard Flameless Hot-Air Burner (soft soldier - 3900btu burner)
All using Propane , they even have a 300,000 BTU tip - the #2944
Got a lot of info here:
http://livesteam.proboards.com/inde...thread=611
Sieverts email is http://www.sievert.se/default.asp?locId=7&langId=1
You might also look at Victor LP-1 Proline,
http://www.build.com/victor-lp-1-victor-lp-1-proline-standard-propane-mapp-torch-kit/p337778
Regards,
Gerald.
PS I have manage sofar with a campstove, a paint striper and a turbo tourch.

 

[shred]

'Goss' is another brand for commercial torches. Depending on the local welding shop, one sells Goss and the other Sievert. Both are available in a wide assortment of packages, handles, tips and gases (the welding places mostly stock acetylene ones, but can get propane). A local model boiler guy has used both brands and says they work well with the right tips.

If you just want a ton of uncontrollable cheap heat, get the HF Weed Burner ;D

 

[ref1ection]

Thank you for the advice on the torches. Will see which is available nearby or by mail.

Ray