Torch for silver solder.

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nealeb

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To clear up any misunderstanding - my problem was silver-soldering a machined phosphor-bronze component to another brass component. I just could not get the SS to flow on to the bronze. I wasn't using phosphorus-bearing rods - as you say, a different kettle of fish.

The problem with learning from someone else's experience comes when two different groups of people have such different experiences! Should I listen to someone who says "no way - doesn't work" or someone who says "don't know what they're complaining about - works fine for me." On the non-cadmium-bearing issue, there are enough people who say it works that I'm inclined to believe them - and my only small-scale boiler work to date bears that out. I can't believe that a large boiler will be using some magically different kind of copper, so except for, maybe, heating requirements it's not obvious to me why my experience to date won't scale.

There seems to be a whole bunch of beliefs around silver-soldering that, in my experience, just don't seem to be true. Like, must degrease surfaces and avoid touching them with your hands thereafter. Nope, not true for me - I might give parts a quick wipe over with kitchen paper if they are particularly grubby but the brass I was working with a couple of days ago didn't even get that - after handling, I assembled the two pieces together, fluxed, heated, and the SS flowed beautifully into the joint. Similarly, read the model engineering magazines from many years back and the recommendation seemed to be "ream the holes accurately to fit the tubes, file three or four nicks around the edge to let the SS flow through." Well, maybe, but the more modern recommendation of aiming for a 3-4 thou gap all round (which does, to be fair, mean that you need to look at clamping arrangements to keep everything in place) gives perfect joints. Well, it does for me using non-Cd silver-solder!

I personally do not know any professional boiler-makers but I don't think that any of them in the UK will be using Cd-bearing SS. Now, their heating capabilities might be different - more likely to see oxy-propane or oxy-acetylene (as per Alec Farmer's classic book from many years ago) - but I see that as a learning opportunity. What I just don't know - yet, and it's not that easy to find out - is how much heat is going to be required for my "big" boiler. I've read some useful info in this thread so far re protective clothing and that's something that I have not really needed with my smaller projects to date. A good chance to learn from other's experience!
 

terryd

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Hi Bluejets,
and all I can say is that is not my experience,

TerryD
 

awake

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Yes - all we can safely claim is what we ourselves have experienced! Whether or not someone else's experience will match ... well, that's why they came up with the acronym, YMMV. :)
 

wazrus

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My next boiler, if I live that long, will be of 7" diameter out of 4mm copper. I've done three others, around 5" diameter, two in 4mm copper and one in 3mm. Mostly, I have used 45% silver, with some attachments using tobin bronze, where there might be a likelihood of 'de-soldering' with subsequent heats. The 7" diameter job is right at the limit of the AMBSC specs - or I think it was - beyond which the boiler became a certifiable pressure vessel. Like others, I have had difficulty with cadmium-free silver solder and always make sure I've got cad-bearing. I've bought the stuff both in Australia and in Hong Kong and the prices, although some years apart, were comparable. But heat and more heat is the operative term: copper has amazing conductivity, as we've all found out. Yes, I have a hearth with firebrick lumps and some coke and this works well, but it's a nuisance when a larger lump of copper, at near red heat, has to be manipulated, so my 'rig' is often the stationary LPG torches on surrounding stands with, as I've said, the oxy-LPG wand at hand. I'm usually a one-man band, so too much fumbling is not allowed. For model boilermaking information, I would strongly recommend the Australian Miniature Boiler Safety Committee's (AMBSC) codes. i believe that the AMBSC codes have become a sort of (de Facto) 'standard'.
 

Steamchick

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Recently I had a lot of success with 55% silver... but when I tried 35% silver found it to be completely different... as you say, it doesn't flow so well. worth the extra cost of 55% stuff to finish my 4 inch boiler!
But we can't buy cadmium in the UK.
K2
 

chrisv

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Hi Nealeb,

I agree with your sentiments entirely. I have too few years left to mess about with heavy metals such as cadmium and the Sievert kit that I have has never let me down and well worth the investment.

Stay safe and healthy,

TerryD
Hi Terry,
Is the kit you use one with flexible tube/s to the gas canister or does the burner part screw direct onto smaller gas canisters, there's so many types to choose from!?!
Chris.
 

willray

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Mostly a lurker here to absorb the occasional trick I've not heard of before, but as someone with a few years of silver soldering and brazing under my belt, a few points I don't believe I've seen made, at least not as emphatically as I would make them to a new practitioner:

First - the two most frequent reasons I see for people failing to get their silver solder or braze to flow out, are insufficient flux, and insufficient heat.

For the flux, too much is just enough. Add flux, and add flux, until the surface is covered with a nice thick layer of syrupy fluxy goodness and you're absolutely certain that you've added more than enough - that's your sign that it's time to add more.

For the heat, pretty much the same thing. I cannot count the times I've seen people (both others and myself as well) fight with trying to get a nice joint, finally in desperation crank up the torch, and suddenly have everything flow out beautifully. The tendency, especially for folks new at this, is to try to baby their way up to soldering/brazing heat. This is usually a mistake. Spend too long getting up to heat, and you'll exhaust the oxygen-scavenging chemistry in your flux, somewhat counterintuitively risk "burning" the surfaces you're trying to solder, and to add insult to injury, you'll melt a million balls off the end of your solder poking at the joint trying to find out if it's ready. You are far more likely to be successful if you go at it like a madman or woman, than if you're timid.

Next, if it's within your means, don't be afraid of Acetylene, or Oxygen/Acetylene systems. True, they are a whole 'nother ball of wax compared to propane (or our dearly lamented MAPP), but they also completely change the game when it comes to silver soldering, brazing, and a host of other things. I absolutely wouldn't be without an O/A setup in the shop. Since the OP is interested in silver soldering together a crankshaft rather than copper tubing, they're going to be needing a lot more deep-heat than tubing wants, and O/A will get them there much easier than propane.

And finally, if you have the option: More torch, not more pressure. Increasing heat by going up a torch size, rather than by opening the valve(s) more, usually keeps everything more controllable.

Best of luck!
 
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terryd

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Hi Terry,
Is the kit you use one with flexible tube/s to the gas canister or does the burner part screw direct onto smaller gas canisters, there's so many types to choose from!?!
Chris.
Hi Chris,

Yes mine is a larger torch connecting to a 7kg propane tank. ait is much more versatile than the small what I call 'plumbers' portable torches although I still use one of those for certain work. The larger tank of propane is much more economical and versatile in teh long run The Sieg has a great range of nozzles to fit the basic torch handle from a fine needle point for fine jewellery work up to a roaring flame thrower, I have a range of them for different purposes. The torch is capable of running at up to 4 bar gas pressure which a large tank can provide.

This is the basic kit I started with and you need to add the initial cost of a propane tank. You can have a look at the range of nozzle/burners and accessories also on this site:


Stay safe and Healthy ,

TerryD
 

terryd

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Hi Chris,

Yes mine is a larger torch connecting to a 7kg propane tank. ait is much more versatile than the small what I call 'plumbers' portable torches although I still use one of those for certain work. The larger tank of propane is much more economical and versatile in teh long run The Sieg has a great range of nozzles to fit the basic torch handle from a fine needle point for fine jewellery work up to a roaring flame thrower, I have a range of them for different purposes. The torch is capable of running at up to 4 bar gas pressure which a large tank can provide.

This is the basic kit I started with and you need to add the initial cost of a propane tank. You can have a look at the range of nozzle/burners and accessories also on this site:


Stay safe and Healthy ,

TerryD
Hi,

I forgot to say that I have also used my Sievert torch for bronze welding tubular fabrications as well as soldering silver jewellery (another hobby).

TerryD
 

terryd

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To clear up any misunderstanding - my problem was silver-soldering a machined phosphor-bronze component to another brass component. I just could not get the SS to flow on to the bronze. I wasn't using phosphorus-bearing rods - as you say, a different kettle of fish.

The problem with learning from someone else's experience comes when two different groups of people have such different experiences! Should I listen to someone who says "no way - doesn't work" or someone who says "don't know what they're complaining about - works fine for me." On the non-cadmium-bearing issue, there are enough people who say it works that I'm inclined to believe them - and my only small-scale boiler work to date bears that out. I can't believe that a large boiler will be using some magically different kind of copper, so except for, maybe, heating requirements it's not obvious to me why my experience to date won't scale.

There seems to be a whole bunch of beliefs around silver-soldering that, in my experience, just don't seem to be true. Like, must degrease surfaces and avoid touching them with your hands thereafter. Nope, not true for me - I might give parts a quick wipe over with kitchen paper if they are particularly grubby but the brass I was working with a couple of days ago didn't even get that - after handling, I assembled the two pieces together, fluxed, heated, and the SS flowed beautifully into the joint. Similarly, read the model engineering magazines from many years back and the recommendation seemed to be "ream the holes accurately to fit the tubes, file three or four nicks around the edge to let the SS flow through." Well, maybe, but the more modern recommendation of aiming for a 3-4 thou gap all round (which does, to be fair, mean that you need to look at clamping arrangements to keep everything in place) gives perfect joints. Well, it does for me using non-Cd silver-solder!

I personally do not know any professional boiler-makers but I don't think that any of them in the UK will be using Cd-bearing SS. Now, their heating capabilities might be different - more likely to see oxy-propane or oxy-acetylene (as per Alec Farmer's classic book from many years ago) - but I see that as a learning opportunity. What I just don't know - yet, and it's not that easy to find out - is how much heat is going to be required for my "big" boiler. I've read some useful info in this thread so far re protective clothing and that's something that I have not really needed with my smaller projects to date. A good chance to learn from other's experience!
Hi Neal,

I agree with you, cad bearing silver solder is not necessary (I like to keep heavy metals out of my body as much as I can), If it will flow on a copper 3" boiler it is only a matter of scale with larger work - you just need more heat. I also agree with the need to not necessarily clean meticulously before silver soldering despite all the 'advice' to the opposite. I use plain borax as a flux - it's cheap and effective and a cone and dish to grind it into a paste with water is available from jewellers suppliers - and it cleans the metal when heated as well as helping the solder to flow and protecting the joint from freezing after soldering, I've been carrying out the processes of silver soldering and bronze welding both for a hobby and professionally for nearly 60 years and cannot remember a failed joint even as an apprentice.

I wouldn't use oxy/propane for silver soldering or bronze welding though, it gives a dirty carbon rich flame which may contaminate the joint, I have no proof of that only a hunch, but many years ago when I used to use oxy/propane for flame cutting up to 2 1/2" thick mild steel plate it was a very dirty flame unlike the nice relatively clean flame that you get with acetylene. My boss would let us only use oxy/propane for cutting as it was cheaper than acetylene and he was a real cheapskate.

Just my personal experiences,

Stay safe and healthy.

TerryD
 

nealeb

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Getting back to the original question! TerryD pointed to the basic Sievert torch, which is fine, but particularly if you are going to be using the larger burners, the 3488 handle is worth considering. The separate pilot control and trigger for main gas flow is useful to avoid having to hang the torch up for a moment with an enormous flame coming out of it! You can also start warming up and drying the flux with gentle heat on the pilot setting before quickly gripping the trigger for full heat without having to fiddle with the control knob.

I'm also a fan of the "cyclone" burners. They have two advantages which are sometimes very useful - they give a different flame pattern which tends to circle round tubular components, giving more even heating, and the air inlet ports are down near the handle, which means that in a confined space, the flame doesn't go out. Which is, at best, embarrassing when it happens...

I have no idea, though, if Sievert kit is easily available in North America - but it is very popular in the UK.
 

terryd

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Getting back to the original question! TerryD pointed to the basic Sievert torch, which is fine, but particularly if you are going to be using the larger burners, the 3488 handle is worth considering. The separate pilot control and trigger for main gas flow is useful to avoid having to hang the torch up for a moment with an enormous flame coming out of it! You can also start warming up and drying the flux with gentle heat on the pilot setting before quickly gripping the trigger for full heat without having to fiddle with the control knob.

I'm also a fan of the "cyclone" burners. They have two advantages which are sometimes very useful - they give a different flame pattern which tends to circle round tubular components, giving more even heating, and the air inlet ports are down near the handle, which means that in a confined space, the flame doesn't go out. Which is, at best, embarrassing when it happens...

I have no idea, though, if Sievert kit is easily available in North America - but it is very popular in the UK.

Hi Neal,

I agree about the 3488 handle, it is very useful to be able to just let the pilot burn between soldering/heating tasks. I haven't really found that a problem though but I may add the 3488 to my setup and possible move the 3486 on to a new owner. At the time I bought my kit I was a bit strapped for cash and couldn't afford the 3488 and have managed to doa wide variety of work with it.

Stay safe and Healthy,

TerryD
 

chrisv

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Hi Chris,

Yes mine is a larger torch connecting to a 7kg propane tank. ait is much more versatile than the small what I call 'plumbers' portable torches although I still use one of those for certain work. The larger tank of propane is much more economical and versatile in teh long run The Sieg has a great range of nozzles to fit the basic torch handle from a fine needle point for fine jewellery work up to a roaring flame thrower, I have a range of them for different purposes. The torch is capable of running at up to 4 bar gas pressure which a large tank can provide.

This is the basic kit I started with and you need to add the initial cost of a propane tank. You can have a look at the range of nozzle/burners and accessories also on this site:


Stay safe and Healthy ,

TerryD
Thank you very much Terry that is most helpful.
I'm gathering pure Propane will give a hotter flame than the Butane/Propane mixed DIY store cans that I'm used too. Also that you can order gas itself online for home delivery. I was looking at the Flo Gas website and thinking a 3.9kg cylinder would suit as I'm not normally a heavy user, it would be lighter weight to move around and smaller to store. Something I'm stumped on though is it says it takes a 21mm regulator. Different size cylinders seem to have different size regulator fittings, so do you have to either make sure you get the right size regulator when you buy the torch, or does what you get with the kit dictate which size of cylinder you can have?
Cheers
Chris.
 

chrisv

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Getting back to the original question! TerryD pointed to the basic Sievert torch, which is fine, but particularly if you are going to be using the larger burners, the 3488 handle is worth considering. The separate pilot control and trigger for main gas flow is useful to avoid having to hang the torch up for a moment with an enormous flame coming out of it! You can also start warming up and drying the flux with gentle heat on the pilot setting before quickly gripping the trigger for full heat without having to fiddle with the control knob.

I'm also a fan of the "cyclone" burners. They have two advantages which are sometimes very useful - they give a different flame pattern which tends to circle round tubular components, giving more even heating, and the air inlet ports are down near the handle, which means that in a confined space, the flame doesn't go out. Which is, at best, embarrassing when it happens...

I have no idea, though, if Sievert kit is easily available in North America - but it is very popular in the UK.
Hi Neal, sounds like you use the 3488 handle with separate pilot, how big is the pilot flame? I had in mind it would be really small say an inch or so, but you mentioning warming and drying the flux suggests its more substantial?

Chris.
 

Steamchick

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H ChrisV: I have a few notions on fuel: Very simply, the hydrocarbon content doesn't define the temperature of the flame: The amount of oxygen (air) mixed with the gas does affect it greatly. I thought Paraffin was cooler than petrol - because my paraffin blow-lamps would not braze, whereas my petrol blow-lamp would. But recently, I rebuilt a paraffin blow-lamp and the flame was MUCH better - as good as the Petrol one.
Butane carries more carbon in its molecules than Propane, so more (denser) fuel. But as the pressure is lower, needs a different matching of sizes to get enough air into the flame for fast (= HOT) combustion. The last few weeks have been too cold (below 10C) in my garage for canister butane blow-lamps to be hot enough on small jobs! - The "reduced pressure" causes the flames to be bigger, more "wooly" and just don't give the focussed heat I need. Propane doesn't worry about temperature above -30C, so is much better in "cooler" climates. The 30% mix canisters you are using will loose most of the propane initially, so the pressure will still drop as the the cannister empties. But initially there won't be the problem I have been having with low-pressure butane canisters in the cold. I only use canister fuel for jobs that will go in a "closed fist" - as the "power" (not temperature) of these blow-lamps is too small for silver soldering anything bigger. Last week I soldered aluminium on the end of a small length of 1 inch channel - but this week I can't solder aluminium on a 5 inch can I am making. The blow-lamp isn't big enough. But I know it is OK when the weather is hotter in summer! (aluminium solder is at about 100 degrees below aluminium melting point. Not the 700 degrees you need for silver solder!).
Propane blow-lamps - because more pressure is available - use smaller jet sizes than Butane blow-lamps - and utilise the higher pressure to get higher velocity gas from the jet - which in turn sucks in MORE air and leads to faster combustion and a hotter, more focussed flame - Ideal for silver soldering. Attached some pics (mock-ups) of some set-ups I use to best apply heat for silver soldering boilers. (I had a problem that the cup-washer on the paraffin blow-lamp fell apart before I got full pressure on this lamp for the demo! - Only 40+ years old! These things are "servicable" items though! - I'll have to cut some leather from a welders gauntlet to make another cup-washer).
Using a horizontal tray of sand and fire-brick, using a vertical tin of sand and fire brick. You can see the 2 types of blow-lamp I use (not hand-held) for pre-heating and that gives me space in the middle for the Propane blow-lamp - using a regulator at 20psi (more and the flame blows-out!). Note the readily available fire extinguisher (To extinguish me if I catch fire!) and the use of extra fire-bricks to enclose the hot job and slow the cooling after soldering.. Both the petrol and paraffin blowlamp will normally get the sides of the boiler a dull red colour, while the Propane blow-lamp applied to the appropriate zone between will get a patch of boiler a decent red to melt silver solder easily. It can't do that without the insulation and 2 extra pre-heating lamps providing more heat. But my left hand cooks inside the leather gauntlet holding the propane blow-lamp! - from the radiant heat from the exposed hot-end of the job. I wear a welder's apron so I don't cook as well!
Watch out that the exhaust from one blow-lamp does not get near the air intake for another blow-lamp, as the flame of that one will be extinguished - with gas going everywhere until it ignites with a WHOOSH! - and sets your clothes on fire. It hasn't happened to me - yet - but I keep the extinguisher handy in case...(!?)
Work safely.
Hope this helps?
K2
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terryd

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Thank you very much Terry that is most helpful.
I'm gathering pure Propane will give a hotter flame than the Butane/Propane mixed DIY store cans that I'm used too. Also that you can order gas itself online for home delivery. I was looking at the Flo Gas website and thinking a 3.9kg cylinder would suit as I'm not normally a heavy user, it would be lighter weight to move around and smaller to store. Something I'm stumped on though is it says it takes a 21mm regulator. Different size cylinders seem to have different size regulator fittings, so do you have to either make sure you get the right size regulator when you buy the torch, or does what you get with the kit dictate which size of cylinder you can have?
Cheers
Chris.
Hi Chris,

The screw fitting for the screw fit propane cylinders is standard as far as I know (21 mm LH), but there are also 'clip on' regulators used for leisure purposes (caravans, barbies etc). You need the 0.5 to 4 bar adjustable regulator not the 37 mb fixed one - most burners are intended to be used at 2 bar. The pro 86 or 88 bought as a kit is cheaper than buying separate parts and you can add on later. The kit I referred to from Hamiltons as an example has the regulator included as does the 88 pro torch kit. You appear to be in the UK and Hamiltons appears to be just about the cheapest supplier out there, I bought mine from a local supplier in Leicester who had it for a decent price, or so I thought and was miffed when I found H's kit cheaper and included the regulator which I had to buy separately.

On reflection, personally I don't consider the advantages of the pro86 burner are worth the extra cost for my use. I think that they are intended for professional users who are working continually during the day and the saving in gas would be considerable. Plus I occasionally use my torch held in a dedicated stand pointing at the work leaving both hands free and I don't think that would be easy with the need to hold the lever. In normal use if I need to put the burner down I simply turn down the flame to a minimum and hang the torch on a dedicated hook where it can do no damage - but that is not very often necessary in my model engineering work - more for my other hobby - jewellery making. That, as I say, is just my personal judgement for my circumstances.

As for drying flux, the sievert torches can all produce a very small soft flame and anyway you can simply keep your torch further away from the work just 'stroking' it with the heat, that has never been a problem for me even on delicate jewellery (I studied jewellery and silversmithing for two years at Loughborough University in the early '70s following my early '60s engineering apprenticeship).

Here is the Hamilton kit as I showed earlier the pro 86 is nearly £69 and they offer free delivery over on purchases over £70:


Update, I have just checked the supplier I use for precious metals and jewellers supplies here in the UK and was surprised to find that they sell Sievert products and are just about the cheapest I can find. Well worth a look even though you might buy seperate items to make up a system. As an example I have just bought a needle point burner for my kit from Cousins at £16.40 including delivery and vat, it is priced at £26.90 on Amazon and eBay and £25.95 at Reeves 2000, so worth a bit of research.


Examples of the type of regulator I use are here on eBay, I bought mine from Flogas:


I also use Flogas as a propane supplier, I fell out of love with Calor when they closed a local supplier and B.Oxy. as they charged an annual tank rental for my tank of MIG welding gas and was costing a fortune, I went with another supplier and bought a tank for the approximate equivalent of 1 years Calor rental and now just pay for refills. I use the Flogas 6kg, tank, it is the same diameter as the 3.9 kg just taller and I find it more economical even though I am now like you a light user, plus it doesn't seem to run out on me at inconvenient times

I apologise for the long winded tract but I felt the need to explain my thinking as fully as I could. Aren't you glad to have a fulfilling hobby in these (hopefully soon to be over) lockdown days, I feel sorry for those who just have the TV and social media to pass the time.

Dammit, my tea has gone cold so am now off to the microwave,

Stay safe and healthy,

TerryD
 
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nealeb

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The torch handle has two controls - main gas flow and pilot flow - so you can adjust according to the burner fitted. For example, if I'm using the needle flame burner, I'll probably just use the pilot control as it is a bit more delicate and there's no real point in a separate pilot flame. For bigger burners, you need to adjust the pilot flame size to suit. Bigger burners need a bigger pilot or the gas flow drops to the point that they go out.
 

terryd

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Thank you very much Terry that is most helpful.
I'm gathering pure Propane will give a hotter flame than the Butane/Propane mixed DIY store cans that I'm used too. Also that you can order gas itself online for home delivery. I was looking at the Flo Gas website and thinking a 3.9kg cylinder would suit as I'm not normally a heavy user, it would be lighter weight to move around and smaller to store. Something I'm stumped on though is it says it takes a 21mm regulator. Different size cylinders seem to have different size regulator fittings, so do you have to either make sure you get the right size regulator when you buy the torch, or does what you get with the kit dictate which size of cylinder you can have?
Cheers
Chris.
Hi Chris,

It will burn no hotter than your small torch, however it supplies more heat energy. There is a difference between temperature and heat. for Example a single spark of metal at about 1300°C from a grinder may sting a little but will cause litle damage to the skin because it contains only a small amount heat, however a cup of scalding water at100°C will cause a serious scald as it contains much more heat energy. Having said that if you stand in the stream of sparks from a grinder it will burn - msny years ago it was amusing to see a fellow apprentice once leaping about beating his groin - he had straddle the length of steel channel he was grinding with a large offhand grinder and the concentrated stream of sparks had set fire to the crotch of his boiler suit🔥

A larger torch will produce more heat energy than a smaller one obviously, the problem with the smaller torch is that you get to a point where heat is being lost from the job than the source (blowtorch/lamp) can provide - hence the need for insulation of some kind (insulation bricks, ceramic heat blankets etc), a larger burner will produce more heat energy but not higher temperatures. The advantages of a torch system such as Sievert or Bullfinch is that it is more versatile than a hand held torch using gas canisters you can change nozzles from a very fine flame to a flame thrower with triple nozzles for roofing and weedkilling plus it is much more economical to use refillable bottles than disposable canisters.

An advantage of propane is that it has a much lower boiling point (-42°C) than Butane (-0.4°C) so you can work at lower temperatures.

Stay safe and healthy,

TerryD
 

firebird

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Hi
I'm a bit late replying to this, so not sure if this has been mentioned above.
For years I managed with the cheapo Machine Mart torch but when I started on my first loco boiler I bit the bullet and bought a Sievert torch kit. Bought it from Cup alloys at one of the model engineering shows.
Back home I was keen to try my new torch so connected it to my propane bottle and had a go. I was a little disappointed, I expected to notice a big difference.
It was some weeks later when I did a full set up and changed the regulator for the one supplied in the Sievert kit.
Now there was a noticeable difference. To prove a point I changed back to the cheapo regulator and there was big drop in power.
I haven't done any research into it but suspect the cheapo regulators do not let as much pressure through as the Sievert regulator.

Cheers

Rich
 

chrisv

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Wow thank you all for so much help...my brain hurts! (-:
Steamchick, some great points there, some I am familiar with but just didn't understand why, now I do and can refer back to this, so thank you. I do have a fire extinguisher for just in case!

Nealeb thank you, that confirms the pilot varies so not as useful as I thought.

TerryD sorry your tea got cold (-: I thank you very much this is all invaluable advice. I will check prices at Cousins.
Its all looking like I should be going for the Sievert kit (without the pilot) for the silver soldering and good to hear someone else uses flogas, and I take on board about the taller cylinder.

One issue for me still to tackle in my mind. Two other uses/jobs I have in mind for this.
Firstly annealing, I sometimes have to anneal 1.5mm sheet brass pieces around 10" x 7". Using my two GoGas cans of butane/propane one in each hand and a base and back screen of Thermalite bricks I struggle to do a decent job, ie thoroughly soften it. I'm gathering the Sievert would cope with this on its own, with a bigger burner, if so what sort of size would be appropriate?

Secondly I have on occasion to forge 1/4" round brass bars, and I have this job upcoming. About a dozen of them which will require several reheatings each.
Currently it would be a DIY can in each hand, once hot enough put these down still burning on their stands on the bench and start hammering on my small anvil, wasting gas of course but lighting them up again each time dosent work out.
That's where the pilot torch handle appealed but since i'd likely have to adjust the flame down i'm not sure i'd gain much. I did look initially at the Bullfinch torches and they have the instant Pizza ignition, but generally they don't look like they have the build quality of the Sieverts, and most kind folks are pointing me towards the Sieverts.

Does this info change the recommendations?

Chris.
 

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