| Gallery, Projects and General > Project Logs |
| Robinson Hot Air Engine. |
| << < (33/38) > >> |
| Stilldrillin:
Just measuring up. Before sorting the wobbly displacer piston...... Is there any reason for the displacer to have .2" clearance at the bottom, (hot end) of it's stroke. And "nil" clearance at the top, (cold end)? :scratch: I can easily extend the shaft by .1", to make both clearances the same. :thumbup: David D |
| NickG:
Do that David, it's quite a bit of clearance though 0.1". What is the clearance around the displacer piston? The hot air engine that I made I think I gave 1/32" all around and at each end. The clearance should be minimal but also enough so that it doesn't cause any sort of drag when squeezing the air from one end to the other. :thumbup: Nick |
| Stilldrillin:
Nick. There's around .08" difference, between slightly distorted displacer, and the cylinder. (.040"/ side). 2.25" bore x .75" stroke. David D |
| Dean W:
--- Quote from: Stilldrillin on February 08, 2011, 08:20:59 AM ---Nick. There's around .08" difference, between slightly distorted displacer, and the cylinder. (.040"/ side). 2.25" bore x .75" stroke. David D --- End quote --- David, that clearance (0.040") sounds okay, considering how large the displacer piston is. I'll (dis)-qualify that by saying I have not built this particular stirling design, but on others the displacer fairly flops around in there. The last one I built had near .020"/ side on a 3/4" diameter piston. For the distance between piston at the top and bottom, the ones I've built have been quite close at the end of each stroke. I would think splitting the top and bottom clearance would be appropriate. |
| NickG:
Was just going to say the same as Dean, that's a relatively small gap so will be fine. You just aim for the least dead space possible but it will be fine. :thumbup: Nick |
| Navigation |
| Message Index |
| Next page |
| Previous page |