Model Engine Maker

Engines => Your Own Design => Topic started by: mike mott on August 04, 2019, 06:03:57 PM

Title: engine for deal sawing machine
Post by: mike mott on August 04, 2019, 06:03:57 PM
Just like a number of other folk on this forum I am guilty of the same thing! more than one project.

After looking at the drawings i have yesterday of other things I began wondering what the innards of the Deal sawing machine engine looked like and since i dont have a drawing other that the three views I showed in the old plate.

here is a conjectural scheme I have started of the valve mechanism at a scale of 1 1/2 inches to the foot the valve travel appears to be .347" and the cylinder bore I am thinking is around 1" and a stroke of 2"

(https://i5.photobucket.com/albums/y169/my30mm/0%20deal%20sawing%20machine/deal%20sawing%20machinex1024_zpsbyxqoqps.jpg) (http://s5.photobucket.com/user/my30mm/media/0%20deal%20sawing%20machine/deal%20sawing%20machinex1024_zpsbyxqoqps.jpg.html)

and without the old section

(https://i5.photobucket.com/albums/y169/my30mm/0%20deal%20sawing%20machine/deal%20sawing%20machine2x1024_zpsewl6f9fx.jpg) (http://s5.photobucket.com/user/my30mm/media/0%20deal%20sawing%20machine/deal%20sawing%20machine2x1024_zpsewl6f9fx.jpg.html)

I am wondering about the valve slide size, and would like to here what the members who are knowledgeable in this area think. as I think it would make for an interesting model.

Mike
Title: Re: engine for deal sawing machine
Post by: crueby on August 04, 2019, 07:23:34 PM
Hi Mike,
That would be a great project!
I have a couple of short write-ups that I collected several years back on valve port proportions, they are attached to this post, some good rules of thumb in them for standard d-valves.

Did a search on that machine, have you seen the writeup it has in the Appletons Dictionary? Starts on page 336, same plates as you show but with details in text.

https://books.google.com/books?id=H3wt6nG0wooC&pg=PA336&lpg=PA336&dq=%22macdowall%22+steam+powered+sawing+machine&source=bl&ots=VxZMq1Q3AC&sig=ACfU3U161VPuq8z7H91UfosYmcrZnnal8A&hl=en&sa=X&ved=2ahUKEwjDhaig7enjAhXkqFkKHZ1CDYIQ6AEwCnoECDAQAQ#v=onepage&q=%22macdowall%22%20steam%20powered%20sawing%20machine&f=false

Chris

Title: Re: engine for deal sawing machine
Post by: mike mott on August 05, 2019, 06:17:41 PM
Hi Chris, thank you for the links I shall read through it all before proceeding. The write ups on the D valves looks to be interesting I have the stuff that Martin Evans wrote in his Book Locomotive Valve gears. The one you linked to seems to be more comprehensive for the theory part.

Good bedtime reading.

Mike
Title: Re: engine for deal sawing machine
Post by: doubletop on August 20, 2019, 08:34:25 AM
Mike

Check out Don Ashton's web page. http://www.donashton.co.uk/ (http://www.donashton.co.uk/) he's a bit of a guru on this subject.

Dons book available here https://www.camdenmin.co.uk/search?q=ashton (https://www.camdenmin.co.uk/search?q=ashton)

Then try the Dockstader simulations http://www.billp.org/Dockstader/ValveGear.html (http://www.billp.org/Dockstader/ValveGear.html)

or the Wallace simulator http://www.avocetconsulting.com.au/modeleng/ (http://www.avocetconsulting.com.au/modeleng/)

Plenty to keep you occupied for a while?

Pete