Sterling Diaphragm Engine

[thanh-cuibap]

Hi Ian !!
combining cylinder made of sus 304 and piston made of Brass : ok ?? It is hard to get cast iron and graphite in Việt Nam !

[Ian S C]

thanh-cuibap, I don't know if you have car wrecking yards in Viet Nam, car engines are mainly cast iron, the fly wheel from a truck motor will often give a good supply. Only trouble is cutting it up, then machining needs a lathe. Brake cylinders and pistons are worth looking at.
Ian S C

[thanh-cuibap]

Thank Ian !! but 95% motorcycles in viet nam , so I want combining cylinder made of sus 304 and piston made of Brass , Do you think it's better than both made of aluminum ???

[Ian S C]

Yes, stay away from aluminium if possible, it's not good for cylinders and pistons. I thought that motor bikes were the main means of transport in Viet Nam. Ian S C

[thanh-cuibap]

Thank Ian..you're right, aluminum cylinder and piston is not good , i made all of aluminum because it is easy to find and easy to do...because : first I want to learn and ...now i want to do better !!!
Thank you again !!!!

[Ian S C]

A thing that will give you a good cylinder for a motor is the internal cylinder of a automotive shock absorber, these are about 400 mm long, with a bore of 25 mm to 40 mm, you might be better looking at motor cycle telescopic front forks.
Ian S C

[thanh-cuibap]

A good idea.... A great idea !! you are a master of mechanical engineering !!
Thank Ian !!

[Ian S C]

No, not a master of mechanical engineering, just a collector of mechanical junk.
Ian S C

[Trevor]

Hey Thanh! I am now changing my Diaphragm Beta engine to a Gamma one and using the air diaphragm for the water pump so I can save some energy from friction of pulleys etc.
Ian, What a great idea of using old shock absorbers for the heating chamber - Thanks guys
Trev

[Ian S C]

Hi Trev, with the old shockies you just have to be careful opening them up, at the telescoping end, just above the oil seal make a cut with a hacksaw until it starts leaking, drain out as much oil as you can (there is quite a bit), keep cutting around, you'll get a bit more oil, and eventually the end will come off, and the chrome plated steel strut, and a fitted steel cylinder will come out. Probably best done outside.
Another thing I got was a couple of drive shafts from trucks, one 4"/100 mm dia, and the other 3"/75 mm dia, these are tubes with about a 2 mm thick wall, and I think some get changed after a certain time to prevent breakage (that can be a bit messy).
Ian S C

[Trevor]

Thanks Ian - I like your mechanical junk ideas, I would not have thought that you could even pull them apart, Good One.. It's great that we all share our info - Do you know of any other forum site that we should be on? There seems to be a few, but seem to do much.
Trev

[thanh-cuibap]

Thank Ian !! combining cylinder made of sus 304 and piston made of Brass : it's better than both made of aluminum !!
[img]

Photo0091.jpg (296.1 KiB) Viewed 16795 times

Photo0086.jpg (284.91 KiB) Viewed 16795 times

Photo0092.jpg (265.6 KiB) Viewed 16797 times

[/img]

[Ian S C]

A couple of other sites I frequent are: www.model-engineer.co.uk , And Model Engine Maker. I'd probably be on more but my dial up connection is too slow, and life is too short. The other one I go to is away from this sort of thing, and covers aviation/ Wings over New Zealand/RNZAF Pro Boards.
Good looking motor.
When choosing metals to work against each other, they should not be like metals, steel with bronze, brass, or cast iron are good combinations, it becomes a study in metalagy. The only metal that will work well against it's self is cast iron.
Ian S C

[Trevor]

Thanks Ian,
Thanh - How do you find using the high temp red silicon in these little motors'
Trev

[Trevor]

The model engineer, I actually stopped prescribing to. They had too much that was beyond my lathe work and kept the projects going over too long a time. That's life ...... Trev