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| NickG:
Well, I finally got a little bit of motivation and got in the garage to cut some metal tonight! A slightly frustrating night but it has yielded 1 component - I started off collecting some materials together but then got bored of that so started turning the bottom displacer cover or hot plate as I've called it on my drawings. I quickly realised that because of the thin register I need to turn that and part it off a longer piece of stock. I have some cast gunmetal that I'm using. The slither that I had planned to use has now ended up as the flywheel! This means I've already deviated from my drawings, when I felt the weight of the aluminium I'd planned to use for the flywheel I thought it was too light, so I thought I'd use the cast gunmetal and thicken it up by 1/16" to 1/4" thick. The diameter has ended up as 1.22" or something rather than the 1.5" I had originally planned. Actually, this now seems a bit heavier than I thought so may have to do the ally one after all but maybe keep the 1/4" thickness, then it might be heavy enough. Anyway, here it is: The cake is 2nd hand, my 2 year old son licks the icing off but he didn't do a very good job on this one so waste not want not! Feel a bit disappointed that that's all I managed in a night but at least it's done. As I said, it deviates from the drawing in size and material. I couldn't be bothered to find / change tools etc either so the recess isn't quite right. I think I will modify the drawing just to widen the alloy flywheel. Unless this one works then I'll change it to brass. The plan is just to loctite it to the crankshaft - just easier for this little engine, it'll have no power so won't come loose. This is probably the 2nd most complex part on the engine so at least it's a start. Nick |
| Stilldrillin:
That looks good Nick.Yer off to a good start. Despite the material decisions/ recycling. :thumbup: You are tougher than me..... I've managed 3off, 20 minute sessions this past week. Before the fingers gave up. ::) Angle grinding yesterday. REALLY didn't need the extra cooling draught it produced...... :bang: David D |
| NickG:
Thanks David, For some reason I didn't feel the cold actually - it must have been the coldest day for a long time yesterday, mind you, had long johns and thermal vest, then a fleece, jeans and overalls on so guessing that helped! Got a bit of carpet in front of the lathe too which helps. What doesn't help is the car sitting behind me with a half dismantled engine and bits everywhere to trip over! Nick |
| NickG:
Did some more in the garage today - again, not as much as I'd have liked. More messing around sorting the parting tool out - it had remained in snapped form since I tried to part off some tough steel but I need it for this. I always struggle turning thin things like cylinder covers for some reason! Not much progress to show, below is the hot plate or bottom displacer plate, the other side doesn't look as good as the parting tool was not on dead centre height so it left a bigger pip that it should of, then I had to file it down - no matter though as it's the underneath of the engine. I have almost finished the top plate which is probably the most complex part - touch wood it's gone ok so far, it had to stay in the milling machine though as just got to drill and tap the hole for the upright then it's finished. I got a good fit with the register on the plastic tube so am confident it will seal well. just need to work out what sort of glue to use. Maybe some quick ish drying araldite? Nick |
| cidrontmg:
Lo Nick, that sure is a small engine! If you need a heavier flywheel, you can solder three twopenny pieces together, and done... I´d be likely to lose most of my ready made parts before I could assemble them together. Even if I kept them in a box, then I´d probably lose even the box... Gluing with Araldite will certainly keep the bottom and the plastic tube together. Even if you later on would like to get them separated :bang: One possible alternative might be "Marston universal jointing compound", that you can get for instance, from http://www.bengs-modellbau.de/werkzeug/werkstattbedarf/marston.php It´s not a silicone but polyurethane, and it never really hardens. It´s easy to take apart if needed, and absolutely tight when in place. The page says it´s blue, but mine is definitely red... Good up to 250C°, at least. The excess (and the stuff itself when disassembling) comes off wiping with a rag with some spirit (ethanol, methanol). I´ve used it in several engines, for gaskets. Despite its English-sounding name, it is made in Germany (http://www.marston-domsel.de/index.php?id=173&L=2&L=2). You don´t need much of it. I bought some years ago a 20 ml tube, and have used it for many engines, when I´ve stripped and put them together again, many many times, during the years. And I still have some 3/4 of it left. It certainly beats silicone gasket compounds (or paper or Klingerite, etc.) in model engines, hands down. And the usual: No connection with Bengs MB, except a satisfied customer. :wave: |
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