Great War truck Posted November 15, 2009 Author Share Posted November 15, 2009 Steve has sent me an update on his progress. The pattern is nearly there now, made up from ash (main body), MDF (flange), a bit of pine (core prints) and filler (the rest!). Once sawn in half, the lost material was made up with some 30 thou plywood and fillets were added using fillet leathers glued on. The reason for using proper timber this time is that the moulder said that he didn't like MDF much as it tends to delaminate when trying to draw the mould from the sand. OK for a couple of uses but not much more. The plan is that he should ram up the flanged side first and then, after turning over, manually cut away some of the sand over the flange so thatwhen the other side is rammed, a piece of sand sticks downwards into the cavity but lifts off the pattern when the mould is split. No doubt time will tell as to whether it works. He is now pressing on with the core box and this should be completed tomorrow. Next part will be the main pump body. Our thanks to everyone for all of their helpful comments. Quote Link to comment Share on other sites More sharing options...
Gordon_M Posted November 15, 2009 Share Posted November 15, 2009 (edited) Is one I mentioned earlier, it's called an "oddside" Doubtless an experienced moulder will have no problem with it at all. The one thing that does stand out is the the core will tend to float when the mould is filled, so I'd expect the moulder to put sacrificial metal studs top and bottom at the bend to hold it in place. Waiting to see the finished castings.... Edited November 15, 2009 by Gordon_M speelungg Quote Link to comment Share on other sites More sharing options...
Old Bill Posted November 15, 2009 Share Posted November 15, 2009 Oh, that's what you call it! Good to have a name. Yes, I have been concerned about the core floating off. I rather hope that the prints in this one will be big enough to secure it but time will tell. Experience is a great educator but there are so many skills needed that I am having great difficulty in acquiring them all! The next one I want to tackle is blacksmithing as the body will have a lot of forged items in it which I will want to make. Best finish the pattern making first though. There are two left to do and I am doing the main pump body now. Hopefully some more pics next week. Steve Quote Link to comment Share on other sites More sharing options...
Gordon_M Posted November 16, 2009 Share Posted November 16, 2009 Just a word about how to get cores not to float then, since we are on the subject. If it was straight, and secured both ends, it would probably be OK. If it had a high-strength reinforced temporary core that would probably be OK too. As it is, when the metal hits the mould, the core will tend to float where the bend is in the core, giving a casting that could look OK but might have a really thick wall on the bottom and a thin wall on the top. The way to get round this is to use sacrifical studs of a similar material to the cast metal - basically brass for this sort of stuff. They just look a little like flimsy collar studs, and you would put one or more underneath near the bend to support the core, then one or more on top to prevent it floating up when poured. There is so little metal in them that they are just absorbed into the final casting, but sometimes you can see the marks left on the cast surfaces, same way you can see screw heads and so on that were used to attach nameplates and number plates to patterns. I'd expect any non-ferrous foundry to have a bin full of them of varying sizes and of suitable metal for just such an occasion as this. Enough casting stuff - I'm going to read the M26 Pacific thread again and try to figure out how to justify one to my better half ...:sweat: Quote Link to comment Share on other sites More sharing options...
Asciidv Posted November 16, 2009 Share Posted November 16, 2009 If you want to follow Steve and develop your pattern making skills and learn more about foundry work then this book is excellent. Barry. Quote Link to comment Share on other sites More sharing options...
Old Bill Posted November 16, 2009 Share Posted November 16, 2009 Are those what they call 'chaplets'? I have heard of them before but never seen any.I guess you must need them for casting muzzle-loading gun-barrels as you could only get a core print at one end. An opportunity for another thread I think! Enough casting stuff - I'm going to read the M26 Pacific thread again and try to figure out how to justify one to my better half ...:sweat: Justification is easy. They make very good paper-weights! Steve Quote Link to comment Share on other sites More sharing options...
Gordon_M Posted November 17, 2009 Share Posted November 17, 2009 As far as I remember chaplets were similar but square / box section, with stud being the cheap collar-stud type. Brings it all back.:-\ Quote Link to comment Share on other sites More sharing options...
Asciidv Posted November 17, 2009 Share Posted November 17, 2009 In my little foundry book, chaplets are referred to as any object used to stop the core from floating. The book suggests the use of flat headed nails. This drawing repeated from 'Foundry work for the amateur' shows all. Barry. Quote Link to comment Share on other sites More sharing options...
Gordon_M Posted November 18, 2009 Share Posted November 18, 2009 Well that's the same function, but there's a couple of things wrong with that image .... The heads of the nails will be too small for the required support - basically they will just push into the core as the float force is quite severe. The shank of the nail is so thick it'll probably not fuse correctly into the parent metal, which will give a whopping defect or at least a severe weak spot at the point of use. The real thing has a decent surface area to support core and mould face, but is basically not much more than sheet metal as regards section thickness to allow it to fuse in. Still, more that we need to get into here, and the diagramme is correct in principal if a bit off in practical terms. I've got the "sheet metal" version of that book somewhere, quite handy. Quote Link to comment Share on other sites More sharing options...
Great War truck Posted November 18, 2009 Author Share Posted November 18, 2009 A Hub Cap has been mounted on the new Half-Shaft - both Hub Caps have been cleaned up and painted - so both Half Shafts are ready for fitting. The one original Half Shaft that we had already had a Hub Cap tightly fitted to it and this has not been disturbed. The Hub Cap/Half Shaft assembly is fixed to each back wheel by six, 3" length, 3/4" BSF Nuts and bolts which are inserted through fitted 1 1/8" diam collets that are a tight fit, half in the hub and half in the wheel. We have managed to re-cover six of the original collets but the other six have been made up here. Apart from the Water Pump where we still await the first batch of castings from the Foundry, the next major job will be making up the Universal Joint assembly between engine and gearbox - we never had one of those. Quote Link to comment Share on other sites More sharing options...
nz2 Posted November 18, 2009 Share Posted November 18, 2009 Tim, The Millers lights you showed on this thread some time back, were these standard issue WD to all makes of vehicles or did differing manufacturers supply lamps to pariticular truck builders? In the last week we have purchased three Millers lamps , one with WD markings but unlike yours no date. That one and a mate are side lamps with small red rear lens and a third lamp is the tail lamp with mounting point at the back and clear side lens. The last lamp is missing its main lens and assume this whole lens was coloured red. Not a common find to three together, in fact this pattern of lamp I have not seen before, but then that could be a matter of location. Thoughts of making replacement lens for other lamps as well using clear epoxy resin. material. I judge the temperature from the burners will be not that great to effect the resin. Interested to know of others exeperiences. Doug Quote Link to comment Share on other sites More sharing options...
Great War truck Posted November 19, 2009 Author Share Posted November 19, 2009 Good question and i think that as WW1 truck lamps is a bit of a complicated subject and not much has been written about it, it deserve a whole new thread in their own right. I will give it some thought and start one soon. However, congratulations on finding a WD lamp. They do turn up occasionally and can really vary in price. Sometimes you can only get a shell as the insides have been gutted for a non WD lamp. A good reflector is the hardest bit to find. At the start of the war the WD purchased any lamps they could find, so you do see all sorts of makes turning up. When they got their act together they commissioned various firms to produce lamps just for them, but these all had WD and the arrow embossed on them. You would have thought that they had made enough to last them forever, but this seems not to have been the case as in 1924 a new batch of lamps were made which were all embossed with that year. I have not seen any other dates. Miller and P&H headlamps are the most common (and look very similar). But there were also Lucas "King of the Road" lamps, although i have not seen one with the WD marking. The tail lamp is the hardest to find and it is a shame that you are missing the red lense. You could maybe make one out of resin or turn one down from a slab of perspex. I wouldnt be too worried about the heat as i cant imagine that you would ever need to light it. With a bit of luck you might turn up a rotten lamp with a good lens and be able to swap it over. Tim Quote Link to comment Share on other sites More sharing options...
Minesweeper Posted November 19, 2009 Share Posted November 19, 2009 We have quite a nice Rear Light in the collection - and I am not sure without looking, which Lorry we put it on - or for which one it is ear-marked if it is not yet fitted. But when we got it, the red glass was very dirty and I decided to clean the glass gently with methylated spirits. I had assumed that it was a solid red glass right through - but not the case. The red was actually some kind of translucent lacquer which had been applied to clear glass to make it red, and with my meths, I had started to dissolve the red to reveal the clear glass! So I quickly stopped cleaning it! So what I am suggesting is that if you have to replace the red glass, then explore the idea of your local glazier just cutting a clear glass disc of the required size - and then "red" it with some kind of transparent red lacquer. I cannot think what to use for that purpose but no doubt someone on the Forum will have a suggestion! Tony Quote Link to comment Share on other sites More sharing options...
Grasshopper Posted November 19, 2009 Share Posted November 19, 2009 A red colour gel as use in theatre lighting would be an easy fix. They would have no trouble with the heat from a flame (they handle high output stage lights) and could easily be stuck to the inside of a glass lense with glue. Quote Link to comment Share on other sites More sharing options...
nz2 Posted November 19, 2009 Share Posted November 19, 2009 The use of theatre lighting gel I have thought of and is readily avaliable to me. It varies in differening densities of colour and would be the easy way to reproduce a coloured lens. Also thought of using the gel within a resin built lens. A question here as to the shape of the red lens; does it have a smooth exterior surface or is it patterned, or what ever the word is to describe the finish of multible cut faces. I note Millers have this multiable cut face lens on the side lamps, where as other manufacturers had a smooth surface. However there is always the question as to how was it done orginally and can it be done again in small batches. The concept of orginallity as per Tim! Doug Quote Link to comment Share on other sites More sharing options...
Great War truck Posted November 19, 2009 Author Share Posted November 19, 2009 (edited) Hard to say for sure. it would seem that some were multi faceted and others were jewel type. I dont think that there was any reason to it, it is just what they had in stock. Both are correct and no one will ever tell you that you are wrong. Here are two Millers, which were both very original when we got them. Maybe one was later than the other. when looking at our lamps, you do get the impression that they were trying to reduce costs as the war went on. Less brass is one change you see. Going from a jewel reflector to a plain one is also quite likely another one. if you intend to make one, I would reccommend doing whatever is easiest. Or do you mean the red lense on the rear lamp, which in fact should just be plain glass. Tim Edited November 19, 2009 by Great War truck Quote Link to comment Share on other sites More sharing options...
Great War truck Posted November 25, 2009 Author Share Posted November 25, 2009 Steve has now finished pattern number five so only one left now. That will be the next step. He intends to make a trial spline for the pump spindle before Christmas too, just to prove it before cutting our precious stainless. Quote Link to comment Share on other sites More sharing options...
Great War truck Posted November 26, 2009 Author Share Posted November 26, 2009 Whilst we await the Water Pump Castings to machine, we have set our minds about making up the clutch and universal joint assembly which we have never had - it was not fitted to the engine in its previous use. The metal for this was purchased for Steve and Tony to machine - three pieces of Steel were the very hard EN24 which does not come cheaply! The one piece for the Clutch Centre measuring 6 1/2" in diameter by 8 1/2" long came out at £73 alone! This was to be a very complicated machining exercise for our Home Workshop and Tony did not fancy doing it - so it was pushed out to a Professional to do for us. He has done a wonderful job - it is sad to say that most of the piece of bar that we had to pay so much for has disappeared in swarf! We are again fortunate that we have original drawings to work from - mainly thanks to Ben. Quote Link to comment Share on other sites More sharing options...
Chrisg Posted November 26, 2009 Share Posted November 26, 2009 Make a nice decoration on the mantlepiece :coffee: Quote Link to comment Share on other sites More sharing options...
Stormin Posted November 26, 2009 Share Posted November 26, 2009 Looks lovely. Unfortunately, I guess, it'll be hidden away and never seen. Quote Link to comment Share on other sites More sharing options...
Asciidv Posted November 26, 2009 Share Posted November 26, 2009 (edited) Tony, I see that you are going to make the water pump spindle in stainless steel. Any particular reason why? The original was almost certainly mild steel, all mine are. A quick look at Wikipedia shows that the first patents for Stainless Steel were only appearing in 1915. Was the clutch centre turned on a manual or a CNC machine? I know that the shaft oil groove spiral is a particularly difficult thing to cut in neatly on a manual machine as I have tried it. Barry. Edited November 26, 2009 by Asciidv Quote Link to comment Share on other sites More sharing options...
Minesweeper Posted November 26, 2009 Share Posted November 26, 2009 The Pump Spindles on the two Autocars were originally of mild steel and we had problems with them rusting, so that there was always a leakage problem. So they have been replaced with stainless steel. We had anticipated the same problem with the Dennis and opted to go for Stainless Steel from the outset. The machining of the Clutch Centre was all done on CNC. You may have noticed that the spiral has unfortunately, been cut the wrong way and may therefore drag oil out into the clutch to soak the linings. We will have to keep an eye on it and if it gets really bad, fill the groove and re-cut it. In the past, we have cut similar grooves with a Dremel - freehand - not nearly so neat but every bit as effective. Quote Link to comment Share on other sites More sharing options...
mkorst Posted November 27, 2009 Share Posted November 27, 2009 Guys, I have been following this project for some time now and all i can say is RESPECT. You are doing a very very nice job! It's always a pleasure to see new pictures and follow the progress. Good luck! Cheers, Micha. www.lucrum-socius.com Quote Link to comment Share on other sites More sharing options...
Old Bill Posted November 27, 2009 Share Posted November 27, 2009 Thank you Micha. I must admit that I am concerned about boring everyone with the endless minute detail. Still, you do keep coming back! There are a couple more pieces on order for the clutch to gearbox connection, again in the very tough En24 steel. We hope to get those in a week or so. In the mean time, I am working on the very last water pump pattern, a simple water elbow, and that should be finished this week. That will see the back of the pattern making for a while which will please me greatly. Metal work shops and wood dust really don't mix and I am desperate to give the lathe a good clean and oiling! Steve Quote Link to comment Share on other sites More sharing options...
AndyFowler Posted November 27, 2009 Share Posted November 27, 2009 Steve we never good bored of good restorations ! Keep up the good work ! :-D Quote Link to comment Share on other sites More sharing options...
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