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| Artie:
Andy, think you may be onto something there. A mate, Tel, from another site suggested the indenting the rivets from the inside to out, but I couldnt see how I could do then inside the boiler circle. This might be the goods..Ill have a play.... thanks mate. |
| Bernd:
Andy, Way back I made a riveter to do rivets for HO scale models. I made it at work. It may not be what you want to make right now but will give ideas. Below are pics with a bit of explination as to what is what. First this is what I'm talking about. The main body is made from a chunk of cast iron about 6" long X 2" inches high and 1.5" wide. The table with the slot in it is 6" X 3" The punch and die made from tool steel (silver steel). The spring is from a pen. The parts are heat treated for hardness. Here are the punch and die assembled into the body. The whole riveter assembled. The arm on the left is set so the hammer is dropped from the same height giving consistent rivets. Here it is in action. Just slide along the back fence, drop hammer, move over to do next one, repeat as many times as necessary. And here they are, a bit blurry, but nice consistent rivets. Ok, time for questions. :smart: Bernd |
| Artie:
Hi Bernd, thats real production line stuff.... dont suppose you want to rent it out for afew day? Of course freight to Aus would be a killer..... I think the concept of the brass strip dented and then soldered in place is the way I will try...Ill do a write up if it works ok... Just about finished the rods. Milled 2.5 mm off each side of the rod beams to bring them down to 6mm (from 11mm), the cheeks of the big ends are still 11mm. I used a jig made from a lump of aluminium left over from a casting experiment. Drilled and tapped it for the rod length, bolted a rod down and did the milling on one side, removed it did the other rod the same and then milled a 2.5mm deep pocket where the big end sits to allow the rod beam to sit flat on the plate and then did the other sides of both rods. And the almost finished product, the gudgeon pins are a press fit into the slide mount and free within the rod, like normal car stuff. I am doing this because you can see how much clearance is avalable when the slider moves up to the oiler cups. I wont actually press anything, heating and freezing and loctite will allow hand assembally. And while I love working with the mill and lathe, I also love handworking my bits. So I do a lot of filing and sanding in the final shaping stage. Dont think for a minute that the rod beams came off the tool that smooth! Now working on the reversing linkage... seems like Kvom has answered a few questions I had by posting his pics over in HMEM...thanks mate! Im pretty much following Edgar T.'s plans to the letter here... its an area I dont have much (any?) experience in... so Ill play on something else at another time.... Cheers Rob |
| Bernd:
Nice looking Artie. The sign of a true craftsman, hand finishing. It looks very nice. On the rivets: that tool was just to give you an idea of how even rows of "simulated" rivets can be made fast. I'm sure for your scale it would need to be scaled up some. Bernd |
| andyf:
Artie, More on the rivets. If their heads at full scale are (say) 20mm diameter, then working on the 111' length of Pevensey and the 7'6" length of your model, the heads scale down to about 1.5mm. I suspect that raising indentations of that size in narrow strips of thin brass might cause the strips to deform out to the edges unless you make up a jig to clamp them in a sandwich between two substantial strips of steel. The top one would need a hole for the punch to pass through and the one underneath would act as an anvil with an indentation for the brass to deform into. Further indentations in the anvil piece would accommodate the "rivets" already formed and also act to index the rivets at regular intervals. Unclamping, moving along and re-clamping might make the procedure rather time-consuming..... Andy |
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