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WW1 Thornycroft restoration

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On 08/01/2018 at 8:27 PM, 43rdrecce said:

Unfortunately, it doesn't specify which 'mechanically propelled vehicles' the matting was intended for.

I believe that our 1916 fire engine should have linoleum pyramidal matting in the places that it currently has pyramidal aluminium, and possibly on the top of the body too. So that would basically be any horizontal lat surface on the wooden body, especially anywhere that people would stand or walk. 

Edited by andypugh

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1 hour ago, Old Bill said:

Hi Barry.I haven't actually cleaned much off, just the two pieces of stick which didn't run so it wasn't much effort.

I think that if you were wanting coupons of braze to run then you haven't quite embraced the nature of bronze welding. It is much more like gas welding than silver soldering. You heat the area with a flame and dab with the rod and/or flux. It is easiest with oxygen-acetylene but I did once do a 3-man bike frame (no lugs) with a carbon arc torch. It's about heating the metal on both sides of the weld to the point that the metal wets, and then adding enough filler rod incrementally to get the fillet you want. 

It might be that you were scuppered by an insufficiently focussed, insufficiently fierce flame. 

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I dropped a coil of filler rod around the joint and then heated until it melted and ran in. The bit which didn't melt was around the back against the blocks and I couldn't quite see if I had got it hot enough. The answer was not!

Do you think it will have run into the joint or not?

Steve     :) 

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I could but I don't think it is worth the effort as it is only the exhaust down-pipe and I had to knock the flange on so the joint is pretty tight. The consequences of failure are very slight.

 

Steve     :) 

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Could be done very simply by fitting a solid plate to seal the flange then immersing in water and blow down the open end  watching for bubbles! 

Failing that a gob of pre emptive exhaust pipe sealer should do the trick.

Tomo

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1 hour ago, Old Bill said:

I dropped a coil of filler rod around the joint and then heated until it melted and ran in. The bit which didn't melt was around the back against the blocks and I couldn't quite see if I had got it hot enough. The answer was not!

I am uncomfortable setting myself up as some kind of expert here, I doubt that I have much more experience at welding and brazing than you do. But brazing is generally done with the torch in one hand and the filler rod in the other. 

It is entirely possible that the problem is that you don't have goggles or an adjustable helmet. Or that you are not watching what the pool of molten metal is doing, and which of the parts is it wetting / fusing to.

Brazing is a 2-handed job. 

You seem convinced that you are a poor welder. Stop that. Some really very stupid people are good welders and it isn't  a dynamic skill like ball games. You just have to watch what the metal is doing and react to / influence that. 

You might want "welding specs" (serious suggestion, my welding mask has a slot or lenses and its a _huge_ help.  If your eyes are more than 12" away from the weld pool you probably can't see enough. 

(note for Observers: This is "peer" advice. I am not a welder.)

 

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I completely agree with Andpugh, brazing is a two handed operation feeding in the brass rod (dipping it in flux as necessary), and following around the joint as it fuses and fills. The braze will solidify behind the flame as you go, which is often important to hold the job together, or if you are dealing with very thin material or bridging large gaps, like when repairing a fuel tank. I also do not attempt to heat up the whole job, just moderately, then apply intense heat at the point of application, and regulate progress so it does solidify behind you.

I must confess I do not use goggles (don't tell my wife!), as my glasses are necessary for me to simply see what I am doing, and I cannot handle goggles as well. Since the flame strength is not sufficient to melt steel or cast iron, its brightness is not as damaging.

Brazing copper or brass items requires quite some care not to overheat, as there is little margin between just brazing and total meltdown!

I am completely self-taught, but seem to obtain reasonable success, and in many cases prefer to braze rather than weld, as I am hopeless at welding.

Also, sometimes it is better to prepare the surfaces for brazing with something course like emery or a file, as grinding can sometimes cause the brass to fail to flow evenly. I also like to turn the job as I go to ensure the molten brass does not simply run off due to gravity. Does this make sense?

Ian

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Thought i’d add a bit in here regarding PPE (yes, H&S, yawn).

For Brazing and Oxy-Acetylene welding this is the type of visor that works well and allows 2 hand operations. Look for a shade 3 visor, and make sure that it will also deal with hot flying materials.

https://www.fastenal.com/products/details/0800425

 

 

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Like some others here, I am not a welder but when I was on the tools I seemed to have a knack for brazing to the point where I could produce neater brazed joints than some of my welder colleagues. Couldn't gas weld though! Its all about the molten pool and dabbing the rod in it. I repaired many a vintage exhaust system with braze. 

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I found this video on YouTube and it gives a good lesson on brazing steel; this is the way I was taught.

You will notice that the plates are set 1/16" apart and when he turns it over you will see that the braze has formed a nice fillet and has not run down the plates.

Steve said he placed a ring of brazing rod around the joint and tried to melt it into the joint as you would do for silver solder but bronze is of a much thicker viscosity and it won't run into close fitting joints.

I remember at senior school we made a garden rake in the metalwork class. This required the round bar tines to be threaded into a length of flat bar. We were instructed to make the threads a rattling good fit because we were to braze them in. The teacher made up the spelter, as it is called, by mixing what looked like chips from brass that had been turned in the lathe and borax into a paste. I can't belive this was all that was in the mixture but when spread over the top of the thread and heated to a dull red with a Flamefast town gas and compressed air torch it melted into the joint without any problems.

John

Edited by Barney
More info

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Many thanks for all of your thoughts chaps. I think that what I really need is more experience of brazing! My heat source is a propane torch so Andy's comment about an insufficiently focussed and intense flame is relevant. I can only get it hot enough by heating everything to a brilliant red. I fed in the stick with my left hand and then chased it around with the flame which worked quite well until I got to the back which I couldn't see or access properly due to the bricks. Silver solder would have run in that situation of course! I just need to do some more and get a better feel for it and possibly invest in an acetylene kit. More food for thought.

On other subjects, the pattern for the stick of tailboard hinges is now finished. That is pattern number 28 with only three left to do.

DSCN7284.JPG.485c06c35647cb5fc15497c99590f78f.JPG

I have also put two coats of primer onto twenty rope hooks which is a tedious job. Fortunately for me, I can now deliver them to the paint shop for top coating!

DSCN7288.JPG.c9f2762f3db3f49c40fd1d3e15770ad6.JPG

More shortly!

Steve     :)

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I believe that for braizing you can use oxy-propane instead of acetylene.

I've only used oxy-acetylene, but have heard it said that the other method will work. All the same kit, just different flammable gas? Hope someone on here can confirm

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You can use any gas combination that will get the parent metal properly red hot. I have used town gas/compressed air, oxy-acetylene and also a carbon arc accessory on a cheap air cooled arc welder with equal success. The key is the correct flux and the parent metal must be clean, free of rust/oxide and paint.

David

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Thoughts are beginning to move towards getting the engine going. To do that, we need a water system, fuel system, oil and electrical system, none of which are complete yet! The water system is closest with all of the cast fittings ready to fit and only the fabricated elbow between the pump and the suction to complete. As you are aware, I bottled out of bending 2" pipe and managed to import an elbow from the US. I have been waiting to fit the cast elbow to see how long the extension should be. I took the measurements last time I was down so I have now extended it to the correct length.

I started by riveting three strips of copper into the elbow to keep the tube aligned.

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Then it was simply a case of riveting on the tube extension and using my favourite silver solder to make both joints. 24 hours in the pickle and the job was done.

DSCN7279.JPG.6f0ebdd2b4cf1e585d3a1e9a4d79e8e0.JPG

The flange is just pushed on for the time being. I shall align the elbow in the flange next time I am down and then silver solder that one as well. Then it will be finished and we will be in a position to assemble the whole water system!

Steve     :) 

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Hi Chaps.

I need some advice please. The question is how do I bend 1 3/8" dia copper tube whilst keeping it reasonably round?

In my efforts to get the engine to a running condition, I have been looking at making up the oil fill tube. This is the one from the Carlton Colville lorry:

DSCN0479.thumb.JPG.6d4aef929f3facb0b3306f4ff2af8d20.JPG

As you can see, it consists of a brass cup on the top of a bent copper tube. I want to bend the tube, which is 1 3/8" dia, to obtain the clearance around the water pump.

DSCN0480.thumb.JPG.4ca371c3db894f2fb1310f7a0a91a3ec.JPG

First step was to make up a bending jig for the press so I turned a wooden bobbin with a semi-circular groove:

DSCN7295.JPG.e81a2cf166af69bc41d5a25fd4d2a6d3.JPG

This, I cut into three and screwed two parts to a base board.

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So far so good.

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When I started to push, there were some ominous creaking noises so I stopped and annealed the tube. When I pushed for the second time, all looked well.

DSCN7302.JPG.844908a7dad8817b4867f2c90f8a825d.JPG

However, the tube simply flattened and spilled over the edge of the timber.

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I then decded to press a bit harder in the un-annealed state but there was a bang and the timber gave up.

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DSCN7306.JPG.0913c713a8af7e379c896a36b3f78587.JPG

All very annoying and I am at a loss to know what to do next. I could lobster tail it as a final resort but it wouldn't be right. Any suggestions would be most welcome.

Steve.

Edited by Old Bill

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If the sand trick doesn’t produce the required result, 1 3/8” is just under 35mm which seems to be the maximum diameter for commercially available pipe benders. Could you ask your go-to plumber?

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Steve,

You have got the right idea except that the wooden formers are not strong enough to contain the sideways expansion of the tube, they need to be made in steel with a groove that is about 1/4" deeper than half the diameter of the tube. The former needs to be a good tight fit on the tube. 

Hope this helps.  John

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Makers of brass instruments apparently use soapy ice:

https://youtu.be/8NAaRQUTp9g?t=3m18s

Plumbers would use a bending spring:

https://www.ebay.co.uk/itm/Internal-Pipe-Bending-Spring-10mm-15mm-22mm-28mm-Tube-Bender-Plumbing/232601166166?hash=item36281c2156:m:mnHtEuP4Pq_282rt49UhyTA

But I can't see one bigger than 28mm. Though I suppose you could make one with a suitable mandrel and some steel wire (wouldn't even need to be spring wire, but would be better as square. 

 

I have never tried sand as a filler, but I have tried sugar, with no luck at all. 

 

I have heard of using lead or Woods Metal. I think that you would need to use a lot o force in that case. 

I have a cheap eBay hydraulic bender that came with a set of cast formers. You can get the formers separately or about £10 less than for the complete tool (so might as well buy the tool or the "free" hydraulic cylinder. 

https://www.ebay.co.uk/itm/6-Pieces-Cast-Dies-Formers-1-2-21-3mm-2-60-3mm-For-Pipe-Benders-12-Tons-New/222336535165?hash=item33c44a4a7d:g:RDwAAOSw2-BZcqSF

But there is no 1 3/8 former in there. 

 

It is possible that you have under-estimated the wall thickness of the part on the other lorry. Thick-wall tube is far easier to bend without buckling. Get some 1 3/8 solid copper bar and drill a 1/2" hole down the middle :-)

 

 

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1 hour ago, Barney said:

Steve,

You have got the right idea except that the wooden formers are not strong enough to contain the sideways expansion of the tube, they need to be made in steel with a groove that is about 1/4" deeper than half the diameter of the tube. The former needs to be a good tight fit on the tube. 

Hope this helps.  John

If he clamped them wood formers in a vice so the sides were in the vice Jaws...then they would be...

 

Steve:

Fill the tube either with sand...

or water and freeze it.... 

That will prevent the tube walls from collapsing.. 

 

Personally I'd fill it with water and freeze it... 

Edited by flandersflyer

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23 minutes ago, andypugh said:

Makers of brass instruments apparently use soapy ice:

https://youtu.be/8NAaRQUTp9g?t=3m18s

Plumbers would use a bending spring:

https://www.ebay.co.uk/itm/Internal-Pipe-Bending-Spring-10mm-15mm-22mm-28mm-Tube-Bender-Plumbing/232601166166?hash=item36281c2156:m:mnHtEuP4Pq_282rt49UhyTA

But I can't see one bigger than 28mm. Though I suppose you could make one with a suitable mandrel and some steel wire (wouldn't even need to be spring wire, but would be better as square. 

 

I have never tried sand as a filler, but I have tried sugar, with no luck at all. 

 

I have heard of using lead or Woods Metal. I think that you would need to use a lot o force in that case. 

I have a cheap eBay hydraulic bender that came with a set of cast formers. You can get the formers separately or about £10 less than for the complete tool (so might as well buy the tool or the "free" hydraulic cylinder. 

https://www.ebay.co.uk/itm/6-Pieces-Cast-Dies-Formers-1-2-21-3mm-2-60-3mm-For-Pipe-Benders-12-Tons-New/222336535165?hash=item33c44a4a7d:g:RDwAAOSw2-BZcqSF

But there is no 1 3/8 former in there. 

 

It is possible that you have under-estimated the wall thickness of the part on the other lorry. Thick-wall tube is far easier to bend without buckling. Get some 1 3/8 solid copper bar and drill a 1/2" hole down the middle :-)

 

 

Come on then pal... 

Show me how your going to bend a 1 3/8 copper tube with a 'spring'.... 

 

Lol...lol...

Sometimes fella...🤔

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37 minutes ago, andypugh said:

It is possible that you have under-estimated the wall thickness of the part on the other lorry. Thick-wall tube is far easier to bend without buckling. Get some 1 3/8 solid copper bar and drill a 1/2" hole down the middle :-)

 

Many moons ago in the plumbing trade thick wall copper tube was known as Soft Copper Coil and was available in sizes from 1" up to 3" o/d, if I remember correctly. It was used for underground water mains and came in a coil which you unrolled along the trench. With the advent of plastic underground pipe I don't know if this is still available or if you could by it in short lengths. Someone like Grahams Plumbers and Builders Merchants or Alreco non ferris metal suppliers might be able to help.

John

 

Edited by Barney
Somthing went wrong with the quote box so have changed it to italics

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