Look for something that puts out around 25000btu (7kw)
Silver Solder Torch Selection
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I agree that a Sievert Propane torch ( big nozzle) rated over 5W is needed for hand-sized jobs..
For Thumb- sized small assemblies only 3 kW is adequate. A hand-held tin of gas cannot give enough fuel, but a 2 kg or more tank is good.
BUT for 1/3rd cost I use old petrol blowlamps that many are frightened by...(I have to good ones!). Holding a can of 1 pint of petrol very close to a furnace at over 1000 deg. C Is madness to some. My oldest (re-furbished) tool is 1933, my newest I bought in 1977. Each gives about 3 kW oof heat, so 1 on the body of a job (maybe a 3 in diameter copper pot boiler) and 1 on the soldering joint, works fine - but only when I assemble the whole lot into a close fitting furnace of fire bricks to contain the heat.
For a 6 in long twin crank in mild-steel, only 1 torch is needed, but only in a close containment of firebrick. I doubt a hand-held can of gas type of burner can give enough heat if this is just lying open on top of insulation board....
The key is "quick heating" which needs "fuel power". Pressurised petrol can do that - to a limit, but a 7 kg propane tank can do 10kW fuel delivery, so the Seivert torch is OK with that on larger jobs.
But I do like 2 or more wet fuel blow-lamps because you can keep the body of the job quite hot with 1 fixed and direct the second along a joint to get top temperature where needed. In a furnace of firebrick the whole job cools much slower so relieving stresses, especially on later joints on a multiple solder job, like a boiler. E.g, soldering an outer shell to end plates with 55% silver solder after pre-assembling fuel into plates using 35% silver solder means the shell has to be at full temperature but flues (already assembled and soldered) are kept cooler. When the whole boiler cool so the differential temperature sets up shrinkage stresses, so slow cooling helps relieve those.
K2
For Thumb- sized small assemblies only 3 kW is adequate. A hand-held tin of gas cannot give enough fuel, but a 2 kg or more tank is good.
BUT for 1/3rd cost I use old petrol blowlamps that many are frightened by...(I have to good ones!). Holding a can of 1 pint of petrol very close to a furnace at over 1000 deg. C Is madness to some. My oldest (re-furbished) tool is 1933, my newest I bought in 1977. Each gives about 3 kW oof heat, so 1 on the body of a job (maybe a 3 in diameter copper pot boiler) and 1 on the soldering joint, works fine - but only when I assemble the whole lot into a close fitting furnace of fire bricks to contain the heat.
For a 6 in long twin crank in mild-steel, only 1 torch is needed, but only in a close containment of firebrick. I doubt a hand-held can of gas type of burner can give enough heat if this is just lying open on top of insulation board....
The key is "quick heating" which needs "fuel power". Pressurised petrol can do that - to a limit, but a 7 kg propane tank can do 10kW fuel delivery, so the Seivert torch is OK with that on larger jobs.
But I do like 2 or more wet fuel blow-lamps because you can keep the body of the job quite hot with 1 fixed and direct the second along a joint to get top temperature where needed. In a furnace of firebrick the whole job cools much slower so relieving stresses, especially on later joints on a multiple solder job, like a boiler. E.g, soldering an outer shell to end plates with 55% silver solder after pre-assembling fuel into plates using 35% silver solder means the shell has to be at full temperature but flues (already assembled and soldered) are kept cooler. When the whole boiler cool so the differential temperature sets up shrinkage stresses, so slow cooling helps relieve those.
K2
Like many things I have I didn’t spend current prices (and was usually able to take advantage of “first order” discounts & free shipping.
While I usually use the Orca as it seems to have a more stable, hotter pinpoint flame, I also have one of these:
https://a.co/d/b1yNGtQ
This might work for larger parts:
https://a.co/d/ffwMq80
This allows you to use “conventional” torch heads at any angle:
https://a.co/d/eFLVY3q
And another alternative for small projects:
https://a.co/d/6UpvNNN
Oh, I forgot: regardless of which torch you choose, get one of these (fits both 16oz “camping” and 14oz “torch” cylinders):
https://a.co/d/do1f3yc
https://a.co/d/do1f3yc
How do you like your Bernzomatic with the hose for silver brazing? Of course, the link you provided for the Worthington hose might be a good alternative if I were to get something like the Goss I linked above: https://www.gossonline.com/air-propane-equipment/hand-torches/trigger-torch
I did look at a video on the Goss on You Tube (starting at about the 2:08 minute mark).
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Chazz, Jason says to look for spec of around 25000 btu. I could not find a spec on the Bernzomatic ones in the description provided in the Amazon links. Do you happen to know that info?
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Roger Taylor
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On e way to get & retain more heat with propane and Mapp torches is to place the parts on a single electric stove top element and preheat. I use a sheet aluminum disk over the element and form a enclosure out of fire brick.
Still got a small burner. You seem to have a limited budget so why buy a small torch and then find it is not big enough for future projects. At least a big torch will work just as well on small items as it will on larger ones.
Try to find something like this. I don't use those two smaller burners for silver soldering. The ones on teh torches are 1" and 1 1/8" and the larger is what I use all the time now.
Try to find something like this. I don't use those two smaller burners for silver soldering. The ones on teh torches are 1" and 1 1/8" and the larger is what I use all the time now.
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Thanks Jason; but, I really don't want something I need to attach to a 20lb tank. Takes up too much space and heavy for me to lug around. I doubt I will every silver braze anything bigger than possibly a small steam boiler and attachments.
MAPP will always be around, it's just propylene gas (same stuff they make rope from) diluted by various brands with propane.
MAP or MPS gas is the good stuff that went away. It was far superior to MAPP. MAPP is the sales acronym they came up with after MPS was removed from the market.
Maybe I need to rethink the tank thing. I see that I can buy smaller 5lb tanks. Looks like your torches are Sievert. Is this Sievert similar to the ones you have been using? https://www.amazon.com/Sievert-Industries-DS2944-Torch-Kit/dp/B00OTJ1I72
Another question, would this fit a standard US propane tank fitting
I have only used the one with a hose for soft soldering (plumbing) and heat treating relatively small tools. I usually use the Orca for Silver Brazing, but again relatively small parts.
Here is response from Bernzomatic regarding the 8000 torch:
I don’t see any tank-mounted size Propane/MAPp Air torch delivering much more than the 14,000 Btu/hr; you’re going to need to go with a Sievert with a large tank (they eat fuel gas) to get 25,000 Btu/hr. That’s what Quinn (Blondiehacks) uses on big builds.
Thanks Chazz. At this point, I am seriously considering the Sievert DS2944 that I linked above: https://www.amazon.com/Sievert-Industries-DS2944-Torch-Kit/dp/B00OTJ1I72?tag=forumyield-20.
Price seems very low compared to other places.
Price seems very low compared to other places.
If you can find the more basic Sievert that just has the one knob that should be cheaper. You don't really need the pilot light and trigger control. This is a typical starter set sold in the UK and Europe
https://cupalloys.co.uk/product/sievert-beginners-torch-kit/
Sorry don't know what the US fittings are but you need a high pressure regulator, 4 bar (about 56psi) is ideal. Don't get a low pressure one for BBQs etc.
https://cupalloys.co.uk/product/sievert-beginners-torch-kit/
Sorry don't know what the US fittings are but you need a high pressure regulator, 4 bar (about 56psi) is ideal. Don't get a low pressure one for BBQs etc.
rklopp
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You want a torch with a hose and stationary tank. When the torch head is attached to the tank, you are unable to point the torch downward where it's often needed, because liquid fuel gets into the burner and snuffs the flame.
I am thinking I may get the Seivert DS2944 that I linked. Or, is it overkill for the crank to crankshaft connection on the Webster engine and maybe a small boiler in the future.
Or, would one of those Bernzomatics like the 8000 torch suffice for this job and a small boiler in the future. I may also want to do some silver soldering on a gas tank for the Webster, if that would be appropriate. Or any other suggestions.
It all boils down to how much I want to spend on something that I likely won't be using very often. But of course, if I spend any money at all, it needs to work.
Edit: actually, I don't think I will ever make a boiler.
Or, would one of those Bernzomatics like the 8000 torch suffice for this job and a small boiler in the future. I may also want to do some silver soldering on a gas tank for the Webster, if that would be appropriate. Or any other suggestions.
It all boils down to how much I want to spend on something that I likely won't be using very often. But of course, if I spend any money at all, it needs to work.
Edit: actually, I don't think I will ever make a boiler.
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Well finally went and ordered a torch like the one on the Muggy Weld website and used in their You Tube videos. It is similar to the Bernzomatic mentioned by Peter which was unavailable. It is one of the ones that Chazz has. It is the Bernzomatic 8250HT like the one in this link: https://www.muggyweld.com/product/bernzomatic-bz8250ht-torch/
I did talk with the guy at Muggy Weld. He was extremely knowledgeable and helpful; and, they do also sell 56% silver solder rods. They have some You Tube videos that show their products being used to braze with the same torch (Bernzomatic 8250HT).
Hopefully it meets my needs.
I did talk with the guy at Muggy Weld. He was extremely knowledgeable and helpful; and, they do also sell 56% silver solder rods. They have some You Tube videos that show their products being used to braze with the same torch (Bernzomatic 8250HT).
Hopefully it meets my needs.
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35% silver rods are cheaper, but a higher melting point. If the job is in a small furnace of fire bricks surrounding the job - except for access for flame and rods....- then you should manage to silver solder steelwork.
K2
K2
