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Big Pcture Thumb Rules

Posted: Sun Dec 21, 2014 11:11 pm
by Bill-W
Helo,

I've been browsing and seen a few comments like this

"this is what i have learned from ian s c, the piston length should be 3 times as long as the diameter."


If your motor is an ALPHA it must have two fitted pistons, and both cylinders have the same volume. If it is a BETA motor, the displacer and power piston are in the one cylinder, and if it is a GAMMA motor the displacer, and power piston are in separate cylinders. The latter two types have a ratio of 1.5 : 1

o
............ and I wondered ............... Is there any central thread on the forum or spreadsheet or book or website that has a list of relevant ratios and thumb rules similar to the above

Am interested n building a LTD coffee cup type engine for starters.

Bill

Re: Big Pcture Thumb Rules

Posted: Mon Dec 22, 2014 12:53 am
by larsinist
That looks like my comments!!
hehe, i nag at ian all the time

LArs

Re: Big Pcture Thumb Rules

Posted: Mon Dec 22, 2014 3:05 am
by Ian S C
Hi Bill & Lars, no there's not Central thread giving info, I just keep repeating it because people don't/ havn't got time to go back and read old threads. Bill I answered your introductory bit won't repeat it.
Bill, the LTD motors are not the easiest motors to get going, but a careful worker should be ok, limit the friction to a minimum, no, or minimal air leaks, and you will probably need to balance the flywheel once the motor is assembled.
Ian S C

Re: Big Pcture Thumb Rules

Posted: Mon Dec 22, 2014 3:36 am
by Bill-W
Ian,

Thanks for your comments I saw your response in the welcome thread as well. I have the Andy Ross book and wil look out for anything by Rizzo.

Bill

Re: Big Pcture Thumb Rules

Posted: Tue Dec 23, 2014 3:20 am
by Ian S C
Bill another thing to look up is the sites on Google by Koichi Hirata in Japan, you'll find a number of plans for hot air engines there on line ready to print out.
Ian S C