Search found 2155 matches

by Ian S C
Wed Jun 20, 2018 1:54 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gamma type cylinder and displacer
Replies: 24
Views: 2646

Re: Gamma type cylinder and displacer

I can only go by what I build, I make the exit from displacer cylinder to power cylinder right at the cold end (I have seen plans where the exit is at halfway). Don't make the transfer port too small. On my motors I try to make the piston larger than the stroke, maybe I'm wrong, but I think the larg...
by Ian S C
Tue Jun 19, 2018 3:03 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gamma type cylinder and displacer
Replies: 24
Views: 2646

Re: Gamma type cylinder and displacer

The normal design of a displacer is that the length should be three times the diameter, although this is not always the case, the Robinson type motor has a shorter displacer, about 1 : 1, but has a internal regenerator. With the 3 : 1 displacer the length of the displacer acts as a regenerator, you ...
by Ian S C
Mon Jun 18, 2018 5:22 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gamma type cylinder and displacer
Replies: 24
Views: 2646

Re: Gamma type cylinder and displacer

If the tube is smooth on the inside, without the ridge caused by welding, a mandrel can be pushed through, and the outside turned down to the desired thickness. I think you should be ok with the 1 mm for the hot cap, but the displacer should be as light as possible. As long as you are not going to r...
by Ian S C
Sun Jun 17, 2018 4:10 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gamma type cylinder and displacer
Replies: 24
Views: 2646

Re: Gamma type cylinder and displacer

For the hot cap, about .5mm in the area to be heated is a good thickness. The displacer could be as thin as .25 mm, I have made them as thin a .007"/.018 mm. Of latter years I have used thin walled tube with an end TIG welded on, I'v got a friend who is a commercial Stainless steel fabricator, he di...
by Ian S C
Sat Jun 16, 2018 4:36 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Tesla's "Ambient Heat Engine" Experiment
Replies: 33
Views: 12952

Re: Tesla's "Ambient Heat Engine" Experiment

Nothing in, nothing out.
Ian S C
by Ian S C
Sat Jun 16, 2018 4:33 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gamma type cylinder and displacer
Replies: 24
Views: 2646

Re: Gamma type cylinder and displacer

For the displacer and hot cap, the best material to use is steel, preferably stainless steel. You want a metal that will not conduct heat rapidly from the hot to the cold end. the resistance to heat conduction directly into the hot end is not impeded as it only has perhaps .5 mm/the thickness of the...
by Ian S C
Fri Jun 08, 2018 3:30 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: the volume ratio between displacer cylinder and power cylinder
Replies: 4
Views: 1024

Re: the volume ratio between displacer cylinder and power cylinder

You won't get enough hot air to the power cylinder. I don't do complex maths for my motors, but 1.5 : 1 is the ratio that Robert Stirling used, and it worked OK for him, and it works for me. The formula is probably quite simple, and probably in the info from NASA that is available on the net. Ian S C
by Ian S C
Fri Jun 01, 2018 1:58 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Whispergen mk4
Replies: 14
Views: 1873

Re: Whispergen mk4

I'm not sure where the 10 W 40 goes, it's what I got off a web site. If its a grease either moly, or a Teflon based one, but don't mix them, specially molly and graphite.
Ian S C
by Ian S C
Thu May 31, 2018 6:27 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Whispergen mk4
Replies: 14
Views: 1873

Re: Whispergen mk4

From what I find on the web, the Whispergen uses 10 W 40, or 10 W 40 Long Drain, I suppose that is a synthetic oil. The coolant is automotive corrosion inhibited glycol antifreeze. The address that I can find is;
Bill Higher
Whisper Tech Ltd.,
224 Armagh Street
Christchurch
New Zealand

Ian S C
by Ian S C
Thu May 31, 2018 1:32 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Whispergen mk4
Replies: 14
Views: 1873

Re: Whispergen mk4

I wonder if wood pellets as used in pellet fires could be used for heating.
Ian S C
by Ian S C
Fri May 25, 2018 3:19 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Whispergen mk4
Replies: 14
Views: 1873

Re: Whispergen mk4

With a different burner it is possible to run on liquid fuel such as kerosene, petrol, diesel. Its possible that someone will come up with a method of using solid fuel with thee motors. I don't know if Peter Lyne looks in on this forum, if he does he knows all about these motors. I don't know where ...
by Ian S C
Sun May 20, 2018 3:58 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Yorky's Twin Cylinder Beam Engine
Replies: 14
Views: 1796

Re: Yorky's Twin Cylinder Beam Engine

There is a wide range of fits of the bearings, so you should be able to find a few good ones. One of the two stove top fan motors that I built has used skate board bearings that are so worn I afraid the balls might fall out. That motor is unusual as Stirling Engines go, it's too powerful, the gyro e...
by Ian S C
Sat May 19, 2018 3:59 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Yorky's Twin Cylinder Beam Engine
Replies: 14
Views: 1796

Re: Yorky's Twin Cylinder Beam Engine

That's a neat way of setting up your crankshaft. If you read a bit about building Stirling Engines, you will come across a bit about removing the shields on bearings, and washing out the grease, these bearing don't have grease. If need be some very light oil, just a very small drop can be used, but ...
by Ian S C
Fri May 18, 2018 3:03 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Whispergen mk4
Replies: 14
Views: 1873

Re: Whispergen mk4

Don't worry they built a few thousand, but I live near Christchurch NZ, where they were developed, and until the workshop and design laboratory was destroyed in an earthquake in 2011. The EQ about put an end to Whisper Tech and the Whispergen. Now I can't call in when I'm in town, have a cup of tea,...
by Ian S C
Fri May 18, 2018 2:50 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Yorky's Twin Cylinder Beam Engine
Replies: 14
Views: 1796

Re: Yorky's Twin Cylinder Beam Engine

You can usually find 6 mm bearings in old VHS recorders, I suppose that they are, or have been chucked out over there. A source of 8 mm bearings (not the best bearings) is Fidgits, I got two for $NZ 1 each, less than 50 UK pence. That fly wheel looks good, it should be quite adequate. I had a motor ...