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| Dean W:
Glad to see an update, David, but not your troubles getting a simple part! I think you could fix the old one, too. A bit of bashing and a few spots hard soldered to fill the holes and... original part back in service. The small dents and dings shouldn't matter to the displacer can, since it fairly flops around in the hot cap anyway. Not like it has to be a close fit. Good luck how ever you do it. Hope it doesn't keep you away from this project for another two months! ; ) Dean |
| madjackghengis:
Well David, call me a cynic, but can you take about half the thickness off the displacer, and gain it as clearance, and get enough to make it run? Jack |
| Stilldrillin:
Thanks for your replies Chaps! Stew. Not sure as I understand "bushing" for fit.... The displacer spinning is oversize to my bore and cap. Only .02" clearance.... I think it should be around .1"....... Unless anyone else has an opinion on what the clearance should be? :scratch: Jack. Frankly, it's slightly tapered, and skimming would only release around another .02", giving .04".... Hardly enough, probably! Peter, Dean. Looking at it, now.... Yes! You're right. I could probably knock it into some semblance of original shape...... Fortunately..... After my, "blunders you make?", posting....... I had a pm from a Gentleman of this Parish, offering to make one for me....... :thumbup: I now have to decide on sizes, and produce a drawing..... Does anyone have any objections to .1" clearance, o/d and .05" clearance either end? Or, any other comments? :wave: David D |
| sbwhart:
--- Quote from: Stilldrillin on April 19, 2011, 02:09:11 AM --- Stew. Not sure as I understand "bushing" for fit.... The displacer spinning is oversize to my bore and cap. Only .02" clearance.... I think it should be around .1"....... Unless anyone else has an opinion on what the clearance should be? :scratch: David D --- End quote --- Nither do I :lol: sorry misunderstood how it worked :hammer: Stew |
| Stilldrillin:
Well..... Here we go again! ::) Unfortunately, shop time is a bit restricted these days. I have to grab what I can, when I can...... As you all know, Gentleman John supplied a new, superb displacer piston..... Assemble with displacer and linkage at bdc. Mark the hole position...... Rotate to tdc. Piece of paper towel holding displacer at tdc. Mark hole position...... This gave two marks, 5mm apart. Drill pin hole central, to give 2.5mm clearance at each end of stroke. Then assemble with piston and rod. Shorten shaft to just clear underside of conrod. (Tiny chink of light showing)...... Orientated the cylinder and bearing pedestal square to each other, and drilled for 1/8" dowels. The air transfer hole was some distance off tube centre. It took a 10mm recess to clean up. Drilled through 5mm....... Machined a brass bush...... Sleevelocked into place to make a recess for an O ring...... Every internal area which had been rusty, had a coat of Hammerite..... Including inner end of the cylinder, and piston crown....... Assembled with new hot cap gasket, and Hylomar....... More twiddling and fiddling to come. Water test to come next! Hmmmm......... David D |
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