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Great War truck

WW1 Thornycroft restoration

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Hi Mike.


I can't quite picture what you are describing? 'A slice in the end of an old punch'? I'm afraid I just hit them!


The first ones I tackled were the baffle plates. They are easy as they don't have any corners.






I just clamped them between the flanging blocks and knocked them over with a planishing hammer using lots of small hits.








They were quite easy and came out well. I even remembered to make one of each hand!




Then came the end plates which were trickier because of the corners. One corner is 3" rad, two are 2 1/2" rad and the last is 1 1/2".




I started by working the straight edges over, either side of one of the larger radii.






I then moved to the corners, again using lots of small hits and working along and around, back and forth.




One of the tricks I have found is that you must not let the curved face kink. If it begins to go, I hold a dolly up behind the kink and knock the high spot back down.








Then it is a case of just keeping at it until it gets there. Lots of small hits.




On the tightest radius, I did put the propane torch on it to help things along. I couldn't quite get it red hot but it certainly softened and helped it go down.




Job done!




On the end of the fuel tank is the driver's instruction plate. I had one of these made in vitreous enamel many years ago and it has been hanging on my bedroom wall for all of that time! Anyway, I felt that the time has come to fit it. As it is screwed to the outer skin of the tank, I thought it a good idea to drill and tap the holes before soldering the skin onto the end thus removing the chance of puncturing the fuel space.




I laid it out on the plate and spotted through the holes.




Then they were simply drilled and tapped. The plate is a bit thin for tapping really but there are plenty of screws and the instruction plate is not very heavy so I think it will survive.




Time to start thinking about the wrapper. That is going to be a real pain to bend and is going to need some tooling. I also need to get the steel cut as a nibbler and file will be too much like hard work. The whole thing is assembled with rivets and soft solder so there are still a good few hours work in the thing!


Steve :)

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Very shortly, we should have steering! The team has been working on different bits and the item turned to our attention today to complete has been the bracket which holds the bottom of the steering column to the scuttle. The photograph shows the same item at the foot of the steering column on the Carlton Colville “Thorny” and this is what we have had to make. Steve made up the pattern for this and it has been cast for us at our local Foundry.



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The casting was given a good wire-brushing to clean it up to start with. The bracket is actually in two parts – as it has to encircle the steering column but cannot be slid down or up it as one complete item so must be made in two parts and bolted together once they have been placed around the column and are in situ. For ease of manufacture and machining, the bracket is cast as one piece and then split into two with a hack saw. But before it is split into two, the clearance holes are drilled for the bolts which will finally hold the two parts together again.





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The two sawn faces of the split casting must be machined flat again, taking out the saw marks, so that they can marry up cleaning together when bolted up with one another. The top part was easy to hold in a Machine Vice but the bottom part was more difficult because it was “angled” and a little cumbersome to hold in the modest facilities of a small home workshop.




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With the two parts of the bracket bolted together, the next job was to bore it out to 2” in diameter which would encompass the steering column. It was deemed unsafe for us to swing the bolted together embryo bracket in the lathe so it was set up in the Mill to be bored out that way. The Mill is only modest so it was going to be a slow job.


The hole was drilled out to 3/4” first of all – the maximum size that we could take on and then a boring head used to gradually take the hole for the column up to the final 2” diameter.






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With the hole for the column taken out to the final 2” diameter, the bracket was removed from the Mill and a piece of the steering column tube tried in it to check the fit. The last job to do on it now is to check the fit of the feet against the scuttle and also their angle – it could be that this may need some adjustment. The holes remain in the scuttle from the original fitment of 100 years ago and it will be interesting to see if everything lines up!





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Posted (edited)
Lead-free solder + lead-free flux actually works very well on plumbing fittings.


But it isn't that good on steel. You can still buy tinmans' solder. (From Cromwell, as an example. And they open Saturday mornings)


Do you think this might have anything to do with soldering pipework to carry portable water..?...:banghead:

Edited by flandersflyer

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Do you think this might have anything to do with soldering pipework to carry portable water..?...:banghead:


Yes I am sure it does. They are removing lead from everything now but the replacements are never so good functionally although not killing you is a plus point......


Steve :-D

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Yes, it's similar to the "unfortunate" impossibility of buying asbestos for insulation and valve packings!

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More work today prompted by the clutch installation. As you can see, there is a gap between the clutch flange and the gearbox input flange. This is filled with a flexible disc coupling of which the original was made of leather.




We are fortunate in that we have the remains of one to copy. Mind you, how they were made is outside of our knowledge. Fortunately another of our dear friends, Mark, a retired submariner, knows all about this sort of thing and very kindly offered to make it up for us. In fact, he made three as the main propshaft flexible joints operate on the same principle.












These are amazing pieces of work and must have taken him ages as well as the severe wear and tear on hands. Thank you Mark. The next challenge though was to put the holes in them in the right place. Now, how to you put a 5/8" hole in 1" of leather? An ordinary twist drill was suggested so I had a laser cut blank made to position the holes with extra screw-down holes in the edge to enable the leather to be trapped against a board.




Then another woodworking pal suggested using a 'Forstner bit' which is something I hadn't come across. It has the advantage of a sharp edge all round to neatly cut the hole without tearing it. I did a test piece and was pleased with the result.




Then I went for it!










The leather is sandwiched between two plates which spread the load from the bolts. These had also been laser cut some time ago. I cut and filed them for the Autocar couplings but I am certainly glad that technology has moved on and I didn't have to do that again!




These have a single securing rivet to each pair so I drilled through the leather, with a twist drill this time, and made up some rivets by softening some ordinary wire nails.






These went quite well.




Job done!




Now we need a clutch pedal and linkage but that will be a story for another day.


Steve :)


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It's interesting that Dennis went through a number of iterations of steel+bronze universal joint variants (see Ben's threads for examples) before going on to use something a lot like those Thornycroft couplings.

The odd thing is that they used Hooke's joints out of the gearbox, but bizarre and rubbish alternatives elsewhere.

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It is amazing what you can do with a few consecutive days of effort! Mind you, these have all been simmering for a while. Anyway, I have been finishing off the drag link.


As you can see, our original drag link was corroded beyond repair. In some areas, only the brazing material remained such was the depth of corrosion.






Some considerable time ago, Father made up a new set of parts including the ends for a new link.






As they were originally brazed, I have been sitting on them pondering on how to put them together. I have great confidence in the reliability of the silver soldering process so I decided that that would be the way to go. The strength would be there and I have the equipment and experience to do it. The only down side is the cost but for one-off, that is not an issue. The first challenge was how to get the solder into the joint. I could have put some down the hole and heated it until it ran out but that came with the danger that the steam produced whilst the flux was drying out would blow the joint apart. I therefore decided to drill a 1/4" hole at the end of the joint and feed the solder that way until it ran out of the other end.






This all went well and the solder ran through beautifully.






Then I had to do the other end. Much head scratching as to how to prop it up in the appropriate position but all went well and this one ran satisfactorily too.
















It was at this point that I remembered that I had to cut a keyway on the inside before brazing! The plan had been to do it before it was too long for the lathe so I engaged in a certain amount of head scratching. In the end, I reversed my keyway cutting attachment so that it faced the tailstock. Then I made up a clamp to hold the link in a vee-block at the end of the lathe bed. The outer end of the link was propped up on a bit of wood and, fortunately, it proved secure enough to plane the slot. It is only an anti-rotation slot for the ball cup inside the casing. The cup needs to be free to move as the ball joint is trapped between two springs.








Another piece ready for painting and fitting. Hopefully, Father can find the tin with the springs and ball sockets in it. It hasn't been seen for a couple of years!


Steve :)

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After giving Father some grief about finding the ball sockets and springs, they eventually turned up on my bench! First job was to dress the locating peg in the ball cup back to 1/4" wide from the original 5/16" dia. in order to fit the slot. 1/4" is as wide as I can cut unfortunately but I don't think there will be any harm done. If anything, it will be an improvement as the contact area is significantly increased.




There are two cups bedded onto some very stiff springs. They are squeezed up by the end cap which is screwed down to secure them. However, the end cap could unscrew detaching the steering from the wheel to the great inconvenience of the driver so it is secured with a spring clip. This takes the form of a ring of spring steel with the end bent over and inserted through the cap into the drag link end to lock it. As you can see, our original has seen better days although there is enough of it there to copy. I used a piece of 1/8" silver steel which I curved in my bending rolls and then bent the end over in the vice. Finally, I heat treated it with the blowlamp on a fire brick, firstly to bright red before water quenching and then tempering to blue before quenching again. Despite the rather hit-and-miss approach it all went very well with a nice springy clip and none snapped off!






Now it is ready for the paint shop!


Steve :)

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I used a piece of 1/8" silver steel which I curved in my bending rolls and then bent the end over in the vice. Finally, I heat treated it with the blowlamp on a fire brick,


For making springs like that it is probably better (and easier) to use piano wire. You can bend it cold, and it will need no heat-treatment.


Cheap on eBay, I keep various sizes in stock.


I might as well mention that I have a lot of 1/4" spring wire left after

as I had to buy a 20-foot roll.

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Yes, Andy, I did puzzle over what to use. However, I had been given a bundle of small diameter silver steel rods and, as they were in stock and just the right length, I used one of them. It seems to be OK.


Steve :-)

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I wish there was a way to make deliberately-inserted links stand out from the random (and generally completely irrelevant) links that the forum software inserts.

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Something else which has been simmering for a while in this part of the lorry are the foot pedals. Long ago, I was given some very poorly pedals but from whence they came I know not. The clutch pedal had been snapped off and a replacement had been fabricated and welded on.




As you can see, the shaft has a distinct curve in it.




First job, therefore, was to straighten it, a simple exercise now that I have a press. What a wonderful tool!




The clutch pedal would have functioned but I felt that we could do better. The pedals were originally steel castings but I thought that a fabrication would be the solution. Fortunately, the brake pedal was sound, if heavily worn so I had a good look at it and drew it up on the board.










A pal very kindly prepared the files and ordered some laser profiles which duly arrived. Notice the slots and tags to assist with jigging for welding.






One piece was bent, another simple task for my home-made press brake in the press.












Next task was to remove the previous repair. I used a thin cutting disc in the angle grinder but it hardly touched it so hard was it! It took ages and I got it very hot indeed.






The I prepared the end for welding. I didn't want a plain butt joint as I was pretty dubious about the quality of weld we could achieve as there is obviously a lot of carbon in it. I therefore stepped it to increase the length of the weld.





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Now, the pedal face. My pal, Adrian, very kindly machined the face and the letter 'C' on his CNC mill and it looked super.




I squared up the ends of the letter using a dental burr in my Dremel grinder. I couldn't help but imagine the cutter in my teeth. Ugh!




To fit, it needed to be curved so I needed to make up a jig. A rummage in the odds box turned this up which, I am reliably informed, is an 'executive toy'. You can unscrew the cap screws and screw them into different holes. Perhaps I just have a short attention span but I didn't find it very exciting so I decided to turn the block into my jig.




All a bit laborious as I could only use a single point tool. It worked though.




And then I did the job, in about thirty seconds! Never mind the job went so well because I had the right tool.








Another trial fit. As you can see, the pedal looks a bit long so I took a bit more off the end.




With the thought that the pedal was amazingly hard, I softened it back before taking it to see Barry for welding. As you know, my welding is terrible and I want some reliability in this one!










Barry did the job but he said the material was awful and the job did not come out very neatly. In fact, he had to get it pretty hot to be able to weld it at all. I wonder whether that is the cause of the original failure?






I noticed yesterday that there is a small eye on the back of the pedal for an anti-rattle spring. This I made up by cutting a piece of steel and then using my favourite silver solder to attach it.








The pedal shaft will now be sand blasted, filled and painted and that will be another one down. In the mean time, it is back to pattern making!


Steve :)

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We spent Sunday on Brighton sea front watching the commercial vehicles come in. We had a super day but it means that our deadline is now less than one year away!


Dad picked up the steering wheel this week after it had been powder coated. It is fine but not really quite as good as the Dennis. Never mind.






A trial fit to find the safest place to keep it!




Now that the drag link is finished, I could fit the last of my ball joints to the drop arm using a slot nut and split pin. No chance of losing it now!




Then it was on to the final fitting of the steering column. Father has machined the column stay so I just had to align it. This was easier said than done as the scuttle had never been on this chassis before and the steering worm is very slightly bent! To get over that, I messed around with shims and also slotted the holes very slightly.




This worked OK and the casting was bolted up. The outer column was then trial fitted and the steering wheel added to the top.






Looking good!




Once the drag link is painted, this can be fitted and we will have steering at last. Now we must make up the throttle quadrant and the hand levers for the throttle and advance.


Steve :)

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Looks great. Doesn't the gearstick position interfere with the feet of the driver?

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The gear lever is well clear of the pedals so there is no problem there. The hard bit is remembering that the handbrake is a pull-on type, not push-on!




Steve :)

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We also gave the pedals a trial fit. They look promising so they are now in the paint shop.




Finally, I tried to install Mark's most wonderful leather coupling between the gearbox and clutch.




The thickness was absolutely perfect and the bolts even went through every hole (the bit I did!). Dad had a rummage and came up with 19 off 5/8" Whit bolts, 3 1/2" long. We cut them down and drilled split pin holes and they look splendid. When he went looking for bolts, I was sure that he would find 17 (we need 18) so the Gods are smiling on us!




Fully installed, with the clutch-brake, but with the nuts un-pinned as I want to see if the leather settles and I can do them up a bit more.




We are very pleased indeed with this. Thanks Mark!


Steve :)

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We are still doing things although never as quickly as we would like. Thoughts have turned to the floor and, although most is timber, there is a steel strip just under the fuel tank.




We took the opportunity to have a piece laser cut at the same time as the fuel tank components but without the slot for the steering column as I wanted to measure it on the job.




This was marked out and then cut.






As you can see, the slot is most of the way across the plate and this did cause me some concern as to its strength. If I had been designing it, I would have folded the front edge down but the original did not have this feature.




The plate sits on ledges at either end and is bolted through.






It was firmer than expected but, as you can see, it sagged in the middle.




For some reason, I had not properly investigated this feature on the vehicles I have studied but I got the photos out and had another look. This one turned up which is of the tipper lorry sold at the Tucker sale in the 1980's.


Charabanc Engine RH.jpg


If you look closely, just to the right of the fuel filter there is something there. I think it is a piece of bent plate with a bolt through the dash and one through the floor.


Detail Charabanc Engine RH.jpg


Looking in the parts book, there are two likely holes so I have bent up a pair of plates, drilled them and they are now in the paint shop.


Floor Plate.jpg




Looking more closely at the parts book illustration, there is a single hole to the left of the steering column. I believe this to be the anchorage point for the clutch pedal anti-rattle spring. I mentioned this to Father and he produced the spare one he had made when he made the brake shoe return spring anchors, all painted and ready to fit!




The other two holes are for the throttle pedal pivot and, as I had previously detailed that, I made it up.












Another Gosling silver-soldered fabrication!




All of these parts are now in the paint shop awaiting the next assembly session. In the mean time, it is back to pattern making. Only thirteen to go!


Steve :)

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