Torch for silver solder.

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Update, for Cousins you need to add VAT so works out £5 more.
There is a Sievert Promatic 3366 handle with Pizza ignition, possibly great, just costs more £££ !
Chris.
 
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?
K2View attachment 123468View attachment 123469View attachment 123470View attachment 123471View attachment 123472View attachment 123473
Hi Steamchick,

What a nice pair you have. I like the one on the left, I presume it's an American one, with it's offset handle for right handed workers to hold in the left I suppose, what make is the other one?

I also like to use paraffin blowlamps occasionally. Here are a couple I bought from car boot sales (remember those?). The one on the right cost me £1.83 as it was all the change I had in my pocket at the time and the seller accepted it! I'm just in the process of cleaning them up ready to use - my last couple were destroyed in a fire - not caused by the blowlamps I might add. I find them convenient and cheap to run and there is a certain satisfaction in using such a simple piece of technology. I stopped using my heating oil (paraffin) in them as the nozzles kept blocking so now I only use grade 1 paraffin intended for indoor heaters which has a much cleaner burn. I made new leather cup washers from an old pair of my shoes when renovating them.



Blow_lamps.jpg

Stay safe and Healthy,

TerryD
 
Update, for Cousins you need to add VAT so works out £5 more.
There is a Sievert Promatic 3366 handle with Pizza ignition, possibly great, just costs more £££ !
Chris.
Hi Chris,

I'm and old timer and still use a flint striker which I've used for years, originally for lighting oxy acetylene torches.

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.
Hi Chris,

The standard burner supplied with the kit would easily manage the brass bar I think, but with sheet annealing it may be difficult to get an overall heat in one go, with 16g sheet I have to apply the heat to an area until red hot and then move the flame slowly across the sheet with the red heat following until the whole has been annealed, I start at the rear working across and forwards so that the sheet is effectively kept soaking. I find that this works well as I often roll my boilers from sheet rather than using tube as I have a good supply of copper sheet in stock.

May I suggest that you make yourself a small furnace for heating bars. I have one made form a commercial size food can lined with fireclay. a through hole runs axially through the centre (can bottom was removed before fireclay added, and there is a radial hole which accommodates a burner for the heat. I should add that the burner is held in a imple support bracket which directs the heat into the furnace and not inserted into hole. Very simple, effective and cheap idea from somewhere on YouTube. My previous one burnt out and I've just made a new one a few weeks ago ready for use when need arises.

Small furnace.jpg

Small furnace2.jpg

Stay safe and healthy,

TerryD
 
Thank you Terry, yes indeed that sounds like a great idea. Just been watching them being made online. I wonder as its only 1/4" bar whether a standard size bean can with smaller inner chamber would be more efficient, or whether there may be a lack of oxygen to work properly...hmmm
Chris.
 
Hi Chris,

I think that you would be better off with the larger size like mine. If you know anyone who works in say a school, pub or cafe etc (our local pub in the village is still open for takeaway meals for example) where they prepare meals you could scrounge a can. I asked the ladies in the local Morrisons restaurant to save me three or four and they were more than willing. You could aways roll some thin sheet into a tube and pop rivet it at a pinch. I have the remains of an old stainless rubbish bin that I salvaged the sheet from and that would be excellent. A pity that you don't live closer I could help out.

The reason I suggest the larger size is that you get a better insulation and can make better use of the heat available as well as ensuring a good flow of air, plus once you use it you may find more uses than you think. I used plumbing waste pipe as a former (coated in soft soap for easy extraction) to make the holes and a hole saw was used in my electric drill for the burner hole in the can before casting the fireclay. The bolts for the legs and handle were also added before casting the fireclay which I scrounged from a local wood burner/stove shop, mixed with horticultural perlite for extra insulation but fireclay for pizza ovens is cheap in small quantities on eBay where you can also source perlite.

If you do make one, apply gentle heat initially and gradually increase it over a couple of days afterallowing it to thoroughly dry out in order to condition the insulation - if you go full blast straight away you are likely to ruin it.

Stay safe and healthy,

TerryD
 
Thanks once again Terry. Yes I'm sure you are right about the size, I will source one somehow. One video I watched used 1/2 & 1/2 sand/plaster of Paris for the insulation. I thought this was interesting as I think I have some sand and tomorrow for work I have to make some plaster castings, no doubt I will have some left over, though I suspect this would not provide such good insulation.
A comment suggested was to angle the burner hole towards the blocked off rear which might produce a more efficient furnace? Presumably not having the heat source entry hole pointing directly at the metal is a good thing? Or others including yourself would have done so?
And or not to have the rear open at all, ie leave the tin can base intact, though I can see issues with withdrawing the drain pipe former. Whichever I do it cancels out my main desire to have a torch that turns on and off instantly, so this furnace is likely to save me a fair wad of £, So thank you again!
Cheers
Chris.
 
Hi Chris,

glad to be of assistance. I made the hole in mine all the way through as it means that I can heat a section of bar at a distance from the end if I need to bend it ,which is what I did when making some holddowns for my woodworking bench. They were made from 15 mm steel bar, bent at past 90° at around 200 mm from one end. The end needed to be flattened to hold down the timber being worked on. I made the burner tube so that it was at 90° to the main tube so that maximum heat could be focussed on a relatively small area of the metal being worked which is the point of the exercise, after all a blacksmith uses the fire directly to heat the metal, he doesn't direct the heat away from the work, I think that is the more efficient use of heat.

I've never used plaster of paris in a furnace but obviously it must work however I would still recommend using perlite and not sand as a filler as it is a great insulator and reflects heat back on to the work, it is often used in furnaces for melting aluminium and brass as it is such a good insulator and helps to conserve heat making the process more efficient, besides, it is relatively cheap. It is the same principle as in my use of insulating firebrick rather than normal firebrick. You can see these in my pictures of my paraffin blowtorches, I can heat the surface of one end of the brick to red hot (which means that it is reflecting not absorbing heat energy) but am still able to hold the other end which means that heat energy is not wasted heating the bricks, the same principle applies to a furnace lining and I fear sand would tend to absorb, therefore waste, heat energy. That is a theory not based on experience just intuition.

As for removing the plastic pipe, a good coating of soft soap and a twist back and forth occasionally while the compound you use is hardening wil make the removal a breeze.

Anyway, let us know how you get on,

Stay safe and healthy,

TerryD
 
Many thanks to all the amazing input, I now know that propane is hot enough to silver solder with and the torch output has to be proportional to the mass of the part to be soldered. I believe I have a Sievert torch lurking somewhere in my garage as I used one to shrink wrap my boat a few years back but that is another story. If I can find that torch, my only issue will be adaption to current BBQ cylinder fittings as they changed the design a few years back in Canada.

Thanks again to all who contributed.

Colin
 
The Chinese seem to make every form of adapter you may ever need, so you can connect standard cylinders to almost anything now. And very cheap... but as always "caveat emptor" - (is that "buyer beware"? Or "sieze the day"? Or "empty cave"?).
K2
 
Terry, the blow-lamp you like is a Sievert 0.5 petrol model I bought mid-1970s. Primus and Optimus paraffin blowlamps are very common and cheap. But the Swedish are masters of petrol blow-lamps, providing you use unleaded pertrol. Until the 1990s I was always making new wicks and de-leading the white compound from my petrol lamps and stoves. The advantage being that when camping, the fuel (petrol) was carried in my motorbike tank and easily withdrawn using a hose on a fuel tap, instead of the hose to the carburettor. Old petrol blow-lamps sometimes become available second hand, usually because they need dismantling and de-leading, and new wicks and leather cup washers. Otherwise they truly last a lifetime! And give quick light-up using a Butane blow-lamp to pre-heat, and the best flame of all.
Really my favourite hand-blow-lamp.
On cup washers, the washers I have made only last 5 years or so, but bought ones are pre-shaped and don't fail after more than 20 years. So I buy if I can find a good supplier of the correct part. It means I can use a blow-lamp after it has sat in the cupboard for a year or 2 and not have to make a new washer half-way through a hot job. Also, it means I don't have washer sized holes in my gauntlets!
Cheers,
K2
 
Terry, the blow-lamp you like is a Sievert 0.5 petrol model I bought mid-1970s. Primus and Optimus paraffin blowlamps are very common and cheap. But the Swedish are masters of petrol blow-lamps, providing you use unleaded pertrol. Until the 1990s I was always making new wicks and de-leading the white compound from my petrol lamps and stoves. The advantage being that when camping, the fuel (petrol) was carried in my motorbike tank and easily withdrawn using a hose on a fuel tap, instead of the hose to the carburettor. Old petrol blow-lamps sometimes become available second hand, usually because they need dismantling and de-leading, and new wicks and leather cup washers. Otherwise they truly last a lifetime! And give quick light-up using a Butane blow-lamp to pre-heat, and the best flame of all.
Really my favourite hand-blow-lamp.
On cup washers, the washers I have made only last 5 years or so, but bought ones are pre-shaped and don't fail after more than 20 years. So I buy if I can find a good supplier of the correct part. It means I can use a blow-lamp after it has sat in the cupboard for a year or 2 and not have to make a new washer half-way through a hot job. Also, it means I don't have washer sized holes in my gauntlets!
Cheers,
K2
Hi Steamchick,

Mine are both Monitor, a No 126 (1 pint) and a No 32 (1/2 pint) both paraffin only models. I've never tried a petrol one but will keep an eye open for when one comes up. Thanks for the advice.

As for washers, I may go proprietary as I'm fed up of my feet getting wet in the rain due to the number of holes💦💦;) I usually treat my cup washers with boiled linseed oil as it is a good preservative and doesn't go rancid and they seem to last well.

stay safe and healthy,

TerryD
 
I use a MAPP gas torch like this one for most silver soldering jobs: MAPP torch
I break out the oxy-acetylene for heavy materials that require a lot of heat.

I use this solder: stay-silv 56% silver solder
It's expensive, so you don't want sloppy joints. But it flows like water, so you don't NEED sloppy joints.

I use this flux: stay-silv black flux
 
I use a MAPP gas torch like this one for most silver soldering jobs: MAPP torch
I break out the oxy-acetylene for heavy materials that require a lot of heat.

I use this solder: stay-silv 56% silver solder
It's expensive, so you don't want sloppy joints. But it flows like water, so you don't NEED sloppy joints.

I use this flux: stay-silv black flux
Hi Jack,

I thought that the original MAPP - methylacetylene-propadiene propane - gas was phased out in 2008. Most so called MAPP gasses here in the UK are called MAP-Pro, (hence MAP-P or MAPP) a substitute for the true MAPP gas and has a different composition e.g. - Propane, propene, dimethyl ether. MAP will burn hotter than Propane but not as hot as the original. Are you still able to get true MAPP in Australia? I note that the cylinder in the torch example you gave said MAP.

Stay safe and healthy,

TerryD
 
Years ago, I decided to be done with second-rate wanna-be torches, went with air/acetylene swirlfire torch heads, and never looked back. No sodding about with preheat torches, firebrick and the like, just light the torch and get 'er done.

Now, for those of you in the UK still buggering about with paraffin and white gas (panel wipe) blowlamps or torches, you can get replacement jets, pump leathers and the like here: https://fettlebox.co.uk/vintage-stoves-lamps-blowlamps.html

Murph
 
Years ago, I decided to be done with second-rate wanna-be torches, went with air/acetylene swirlfire torch heads, and never looked back. No sodding about with preheat torches, firebrick and the like, just light the torch and get 'er done.

Now, for those of you in the UK still buggering about with paraffin and white gas (panel wipe) blowlamps or torches, you can get replacement jets, pump leathers and the like here: https://fettlebox.co.uk/vintage-stoves-lamps-blowlamps.html

Murph
Hi Murph,

One reason I'm buggering about with paraffin petrol and propane is that they are efficient, convenient relatively safe and have worked for all my needs large and small for almost 60 years, having said that I admit that a good level of skills are needed to get the best from these products. I also began buggering about oxy-acetylene welding and flame cutting when I began my Engineering apprenticeship in 1963 and taught the safe use of it and used it in the workplace for many years and have undertaken courses in with British Oxygen (BOC) and agree that it is easy to use. It can be quite unstable and even a hard knock can set the stuff off, one of the earleist things the guys taught me when handling the large industrial cylinders was that if dropped while changing them their advice was to "run like the devil is on your tail".

However there are a couple of reasons I don't use it at home. the first one is that if not declared it can invalidate my home insurance (I suggest that you check with your company) and secondly when I had my garage/workshop fire the firefighters who attended were only worried about the possibility of acetylene cylinders. After the fire the firefighters told me that if there had been acetylene they would not have 'fought' the fire but just contained it from a distance to prevent spread and it would have been allowed to burn down completely. They were not concerned with paraffin, LPG gasses or even the 2700 litres of heating oil in it's tank inside the building. They were determined not to bugger about with acetylene.

Stay safe and healthy,

TerryD
 
Are you still able to get true MAPP in Australia?

I guess not Terry. I just assumed it was MAPP because it was a yellow cylinder. I didn't realise MAPP had been phased out. The cylinder I have is >95% Propylene and labelled as "MAPP Replacement". Burn temp is quoted at 1982 degrees C. Apparently the old MAPP burned in air at 2020 degrees C.
 
Interesting Jack. I didn't know they could quote "temperature" for combustion, as (in my un-educated stupidity) I thought the gas burned the Hydrogen in the first part of the reaction, then C + O = CO and finally CO + O2 to CO2 in the final stage of combustion. So in my mixed-up mind all hydrocarbon fuels are different calorific values but temperature is a product of how the gases mix and how fast each reaction occurs at each stage..?
Thanks Murph. I'm trying to get a UK supplier to supply the cup-washers I want. Fettle-box came back with "closed for a week". I'm cutting washers from my welding gauntlets at the moment - but the leather only lasts a few years compared to bought cup washers.
As I have inherited 5 paraffin blow-lamps, fuel is relatively cheap and easy to manage, and for my jobs the Propane and Petrol Blow-lamps are powerful and reliable and adequate heat sources, I'll not be trying any other fuels for a while. I did have a problem this last week trying to do a titchy little aluminium soldering job with Butane. So cold (below 3 degrees in my garage) that the butane canisters just failed to boil enough gas to feed the blow-lamp! But it was just enough to pre-heat the petrol blow-lamp which easily did the job (almost too much heat - high risk of melting the aluminium!).
Stay safe! - and warm.
K2
 

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