| Gallery, Projects and General > Project Logs |
| Gold Blend. A Coffee Jar Engine........ |
| (1/24) > >> |
| Stilldrillin:
A couple of weeks ago, after finishing Rizzo, I had a vague idea...... Something larger. Perhaps! :scratch: To maybe, make a hot air displacer cap, from a stainless steel salt/ pepper pot. :thumbup: So, I took a walk in my local Wilkinson's.... And found a coffee jar too! :D Here they are, leaning affectionately upon each other........ I gave the jar some thought....... A medium temperature hot air engine! It will need a plug to form the top deck. Soon, I had topped an old square piece of 1/4" alloy, into a round piece of 1/4" alloy....... Something like this sort of idea. At 11mm down, it could hold water, for cooling...... Someone, somewhere, has mentioned balsa wood, for a displacer. Mounted on 4mm dia silver steel. Messy stuff......... Next up, two .9mm steel discs. Turned .1” under the 3.75" bore size........ This was the collection at yesterday's knock off....... At 1" stroke, what diameter power piston should I go for? :scratch: I'm just drifting along with it....... Allowing it to develop....... :) Anyone any thoughts/ input? David D |
| sbwhart:
Now this looks interesting :mmr: Stew |
| arnoldb:
Nice one David :thumbup: :scratch: Don't know about the power piston diameter; Stirling engines are still a bit of an unknown to me... But I would have thought that you would have hollowed out the balsa sandwhiches in between the outer ones a bit to drop a bit more weight :scratch: Looking forward to your progress though :D :beer:, Arnold |
| DaveH:
David, Looks very interesting :thumbup: :beer: DaveH |
| NickG:
David, Looks like a great start to me. :thumbup: Is the displacer still quite light with that rod? Will all need to be light for this sort of engine. Are you going to use graphite for the power piston or will it be a bit hard to get in that diameter? It would be a good idea as light, self lubricating and easy to get a good fit. Prob worth doing for the displacer rod guide too but the brass you have there might work if it's a good fit. Leaving a recess for water sounds a good idea to me too. You could always stick a tea light under it if you find it needs more heat too. As I always bang on about, for an LTD you generally need a fairly high ratio of swept volumes, but I'm not sure how high. Assuming you are making the displacer and power cylinder both the same stroke (you don't have to since there will be two cranks) and your Power Piston bore looks about 1"? That would give you a 13.3225:1 ratio which is relatively high but not sure whether it's high enough. I've got some pics of a commercially available LTD which worked really well, I could try to scale those off and get some idea if you think it might help. That thing could run from the heat of your hand with no cooling to the top plate! Nice work :beer: |
| Navigation |
| Message Index |
| Next page |