Scrunt & Farthing Posted July 5, 2020 Share Posted July 5, 2020 What foundry are you going to send them to, Ben? I have no experience of Alu in v.low volume, only Bronze. I need to make some similar bits for my Leyland at some point. Dave Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted July 12, 2020 Author Share Posted July 12, 2020 On 7/5/2020 at 7:31 PM, Scrunt & Farthing said: What foundry are you going to send them to, Ben? I have no experience of Alu in v.low volume, only Bronze. I need to make some similar bits for my Leyland at some point. Dave I think I will be visiting the foundry with a batch of patterns this week so I will check he is still happy to do aluminium and for me to give details here. The 3D printer has been used again to make the core prints for both ends of the header tank. The first step was to glue ans screw them on. Filler was used to cover the screw heads and tidy up any small gaps. The front half of the header tank pattern is now finished but I need to confirm the locations of the features on the back half. I don't have the drawings so it is being scaled from photos and chassis details but I am still not sure if there should be a flange for attaching to the front of the bonnet. I took some of the bits of wrought iron to work and blasted then in my lunch breaks. They have had a couple of coats of Bondaprimer 2 Quote Link to comment Share on other sites More sharing options...
Foden7536 Posted July 13, 2020 Share Posted July 13, 2020 Where are you based Ben? I get aluminium castings done by “Harling Foundry” in Hastings, they are very sympathetic with work on older stuff and delicate with patterns. They do quite a lot of vintage and veteran car stuff for me. Lloyd (the boss man) is very pleasant and knowledgeable. 01424 443160 If that’s any help. 1 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted July 19, 2020 Author Share Posted July 19, 2020 On 7/13/2020 at 8:57 PM, Foden7536 said: Where are you based Ben? I get aluminium castings done by “Harling Foundry” in Hastings, they are very sympathetic with work on older stuff and delicate with patterns. They do quite a lot of vintage and veteran car stuff for me. Lloyd (the boss man) is very pleasant and knowledgeable. 01424 443160 If that’s any help. Thanks, I am based near Birmingham, my usual foundry appears to have been on holiday this week but has the advantage that I can get there in my lunch breaks. Good to know there are others out there. Not too much progress on this particular project this week, I have just been putting metal back onto some of the body ironwork where it has been cut or broken off. The repair pieces are being machined from EN3 steel and arc welded to the wrought iron. These ones make up the back corners of the body and carry the rear hoop. 1 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted August 9, 2020 Author Share Posted August 9, 2020 Virtually all of my casting work is done by Andy of AJD Foundries. I can get there from work during my lunch breaks and I have been really impressed with the quality of work. The water manifolds have turned out well; the foundry seemed quite happy with the 3D printed patterns so I can continue to use the printer for the smaller patterns and details on the larger ones. The pipe bend for the radiator outlet also looks good. When I have finished the patterns for the radiator and made the patterns for the water pump there will be somewhere to fit it. 3 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted October 11, 2020 Author Share Posted October 11, 2020 Although I have drawn the radiator out in CAD, I wanted to check the dimensions against the engine and chassis before gluing any of the 3D printed features in place. No drawings have survived for the radiator so it is all worked from photos and chassis dimensions. A little bit of glue, filler and some paint completes the spilt pattern for the top tank but I still need to make the core box before I can drop it off at the foundry. The sides are pretty much finished now (just need to polish the pattern coat). Quote Link to comment Share on other sites More sharing options...
andypugh Posted October 11, 2020 Share Posted October 11, 2020 How does the top tank attach to the radiator core? Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted October 11, 2020 Author Share Posted October 11, 2020 2 minutes ago, andypugh said: How does the top tank attach to the radiator core? It is a horizontal tube radiator, the two brass tube plates get sandwiched between the cast sides and the top tank (with lots of 1/4 BSW cheese head screws). Only one of the tube plates has a hole in it to let the water through. The baffle in the cast sides put banks of tube in parallel giving the water a serpentine path (putting each bank of tubes in series with the next). The radiator outlet is at the bottom of one side. The brass pipe bend I had cast recently fits to the radiator outlet and is coupled to the water pump with a piece of flexible hose. Quote Link to comment Share on other sites More sharing options...
andypugh Posted October 11, 2020 Share Posted October 11, 2020 15 minutes ago, BenHawkins said: The baffle in the cast sides put banks of tube in parallel giving the water a serpentine path (putting each bank of tubes in series with the next). How mildly insane! Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted October 25, 2020 Author Share Posted October 25, 2020 I needed to get some parts cast for other projects; it seemed to make sense to get the radiator sides cast at the same time. There is a brace across the bottom of the radiator but the pattern was too big to print in one piece so I split it into four. I included dowel holes so I could fit them together with glue and some 4mm steel rods. It needed a little filler and sanding but is nearly ready for some pattern coat. With that success in hand we continued to print the components for the front half of the header tank core box. I ran out of filament for the printer but was able to glue and screw most of the pieces to the MDF board. I don't know if the foundry would prefer to pack sand into the assembled core box or prefer to mould the two halves and glue them together but the design allows for either method. 4 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted November 1, 2020 Author Share Posted November 1, 2020 The core box is coming along pretty well, the front half is basically complete. The two bosses thicken up the casting so I shouldn't break through when drilling and tapping the casting for the name plate. The back half will be slightly more complicated as it needs to allow for the overflow and water inlet port. The printing does not always go to plan; in this example the nozzle had a blockage and as a result subsequent layers were under-extruded. Most of my prints are around 12 hours and I think my failure rate is less than 5% or about every 240 hours of printing. So far I have not printed any pattern structure that I could not have made in wood but the printer can be going whilst I am earning a living or working on other projects. The glamorous assistant is working from home at the moment, so can switch it off when things go wrong. 2 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted November 8, 2020 Author Share Posted November 8, 2020 The glamorous assistant kept an eye on the printer whilst I was at work this week as she continues to work from home. I am lucky to work in a manufacturing environment so have managed to continue to travel the short distance to work each day and have not yet exhausted the projects at home. I milled the slot in the MDF backing panel for the overflow pipe connection and cut a 44mm diameter hole to accept the 3D printed piece for the water inlet. That should pretty much finish the core box if the paint polishes smooth enough once it has dried (just the pattern coat to go). 3 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted November 15, 2020 Author Share Posted November 15, 2020 The radiator patterns still need a little bit of tidying up so I am unlikely to get them to the foundry this week. For two of our other projects I am trying to make some sense of the numbers on White and Poppe carburettors. They are variable jet carburettors; when the throttle opens the variable jet is also simultaneously opened. However, the handbook suggests the size of the regulating jet and how far it is offset from the axis was varied by the manufacturer to suit the particular engine requirements. Each float bowl lid is marked with the serial number and a series of numbers along the lines of 30.450/500 (1/32). The 30 refers to the diameter of the throttle bore but I am not yet certain of how the rest of the numbering system works. The carburettors are also handed to make finding a replacement more difficult. The carburettor that came with my engine was quite grubby and does not want to come apart. The throttle barrel has signs of having been chiselled out in the past (quite a bad sign) so I decided to immerse it in WD40 for a week before giving it another go. I didn't have enough WD40 so I topped it up with heating oil. 1 Quote Link to comment Share on other sites More sharing options...
Asciidv Posted November 20, 2020 Share Posted November 20, 2020 On 7/13/2020 at 8:57 PM, Foden7536 said: Where are you based Ben? I get aluminium castings done by “Harling Foundry” in Hastings, they are very sympathetic with work on older stuff and delicate with patterns. They do quite a lot of vintage and veteran car stuff for me. Lloyd (the boss man) is very pleasant and knowledgeable. 01424 443160 If that’s any help. Without any doubt the best foundry for our kind of work in the North East is the William Lane Foundry in Middlesbrough. There is a lovely video of what they do on their website. https://www.williamlanefoundry.uk/ They have cast Thornycroft radiator tanks and if you catch them at a time when they are pouring the metal that you need they might even produce your casting whilst you wait. 2 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted December 6, 2020 Author Share Posted December 6, 2020 One week of immersion didn't seem to be enough time to free off the carburettor, but after three weeks and with the assistance of some heat the outer throttle was persuaded out of the body. A day later I managed to remove the inner throttle from the outer throttle. When reassembled none of the parts rotate freely so I will need to spend a couple of hours with some micrometre blue and a scraper to undo the damage done by the mechanic with a chisel. The car project I have been working on is nearing completion so with a couple of hours to fill I decided to machine the castings that connect the water jackets of the four cylinder blocks. One of the broken and corroded originals is in the background. I came up with an alternative craft advent calendar; the glamorous assistant is coming out to the workshop after dinner and making the old Whitworth (BS190) type fasteners for the gearbox. She has made 16 off 5/16 nuts so far so we are a bit ahead of the plan; I might even be able to increase the scope of works at this rate! No Christmas parties to get in the way this year so all the evenings are available. 4 Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted December 13, 2020 Author Share Posted December 13, 2020 I collected the completed castings from the foundry. The header tank design meant the foundry got to spend a couple of hours getting the core sand out through the small holes. I couldn't wait to get on with them so did some of the rough machining. The casting was supported on some 3D printed blocks to keep it vertical, they also fitted into the slots in the table to keep it straight. I have ordered a more appropriate cutter to finish off the ends but it will probably not arrive this year. I have blasted and painted the first batch of nuts and bolts made by the glamorous assistant. Nearly all the gearbox fasteners are complete so we need to come up with a few more items to add to the list. 1 Quote Link to comment Share on other sites More sharing options...
Asciidv Posted December 13, 2020 Share Posted December 13, 2020 Ben, Looks very good! What length of end mill do you need to get to the bottom of that face? Did you finish off the screw cut bolts with a die? The thread length looks very uniform or can your glamorous assistant throw your lathe into reverse with super fast reactions just at the right length? Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted December 13, 2020 Author Share Posted December 13, 2020 42 minutes ago, Asciidv said: Ben, Looks very good! What length of end mill do you need to get to the bottom of that face? Did you finish off the screw cut bolts with a die? The thread length looks very uniform or can your glamorous assistant throw your lathe into reverse with super fast reactions just at the right length? Barry, the end mill only needs to cut just over 3". I have a 14mm end mill that will cut more than that; it has a 12mm shank and I use it with my Diemaster mill but it is not stiff enough for this job (and I don't have a 12mm R8 collet for the Bridgeport I am borrowing). There is no rush to complete the task so I will wait for the long series 20mm end mill to arrive. I can get on with machining the other casting, ordering tube plate material and other projects so there is no risk of thumb twiddling over the Christmas break. For the bolts we just mark a line on the blank with a marker pen and wind the tool out when we get that far, finishing off with a die nut. For the 1914 Dennis we mostly used modern off the shelf BSW & BSF bolts and just machined the numbers off the heads but we are a bit more pedantic with the earlier vehicles where even a BSF bolt looks out of place. Quote Link to comment Share on other sites More sharing options...
BenHawkins Posted December 20, 2020 Author Share Posted December 20, 2020 The glamorous assistant has finished the advent calendar well ahead of time. That is a full set of fasteners for the gearbox so she has moved on to fasteners for other parts. I have done more of the machining on the radiator castings. One lunchtime I picked up the tube plates which came in cheaper than expected; if you base your costings from online retailers, it is often rewarding how much cheaper you can get them from a company on your doorstep. I have to confess it was nice to be able to buy the 1/8BSW screws for the badge off the shelf. Unfortunately the radiator gills have come in a long way over budget. I had a quote for these a few years ago but the company no longer does radiators. The new quote is a significantly higher sum; so high in fact that it is more than the pattern making, castings, tube plates and tubes put together. The gills are made from 0.010" (0.25mm) tin plated steel 15/16" across flats to fit 3/8" diameter tubes; I need around 14,000 of them. The price quoted has made me consider punching them out myself but so far I am unsure how the profile is achieved. 14,000 on the fly press may be more than I can ask of the glamorous assistant; perhaps I should offer to do 7,000. 3 Quote Link to comment Share on other sites More sharing options...
Asciidv Posted December 20, 2020 Share Posted December 20, 2020 Please make them! I am sure that we would all like to see how you go about it. You could imagine if you blanked them first and formed them in a second operation then the tooling would not be that difficult to produce. To do it all in a single hit needs a bit more thought. I wonder if the turned over tips of the segments are really necessary? Quote Link to comment Share on other sites More sharing options...
Old Bill Posted December 20, 2020 Share Posted December 20, 2020 Go on Ben, you make them! That is a very common size so there is a potential market there. I would suggest doing them in a single action would be worth the tooling effort for so many of them. The ones we had done for the Thornycroft didn't have the points turned over though. Good luck with that. I know you like a challenge! Steve Quote Link to comment Share on other sites More sharing options...
mammoth Posted December 20, 2020 Share Posted December 20, 2020 I have a box of 18,000 purchased some time ago for a now stalled project. I would have hoped that the automated punch must still exist. maybe not. The turned over tips are good because they determine very consistent spacing. When it came to finding someone with capacity or knowledge on soldering them to the tubes I discovered that it is now a 'lost trade', so will watch with interest. Quote Link to comment Share on other sites More sharing options...
andypugh Posted December 20, 2020 Share Posted December 20, 2020 (edited) 37 minutes ago, Old Bill said: Go on Ben, you make them! I wonder if it is really as simple as a pentagonal pyramidal spike inside a square hole? (ie. like this https://a360.co/3pagTbb ) And would a hexagon work? Edited December 20, 2020 by andypugh Quote Link to comment Share on other sites More sharing options...
Asciidv Posted December 20, 2020 Share Posted December 20, 2020 Andy, I think the simple pyramid would just tear the metal as it forced it’s way through without any cutting action. Should we have a Christmas competition to design the best punch as there will be nothing worth watching on TV? Quote Link to comment Share on other sites More sharing options...
andypugh Posted December 21, 2020 Share Posted December 21, 2020 4 hours ago, Asciidv said: Andy, I think the simple pyramid would just tear the metal as it forced it’s way through without any cutting action. It might need to be pointier. I think that, ideally it would be a double-action, where the square and inner ring is punched first,, then the spike comes up through the clamped, shape-locked ring and bursts it. But I don't know how you would do that. Possibly with a spring, but a spring stiff enough to punch the initial hole? Quote Link to comment Share on other sites More sharing options...
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