Author Topic: Gas Firing the Scott Vacuum Engine..........  (Read 6816 times)

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #15 on: December 05, 2015, 09:02:39 PM »
So how did the cut down shroud work out David? I hope better than your finger made out!!
Bill

Hi Bill.
 Perhaps, I was a little hasty, cutting down the roof so much. But, it has improved the running.
I can control the revs with the burner. Just needing to turn it down, slowly. Not so many blowouts!  :whoohoo:

I'm now working on a shield, behind the burner verticals. To meet the roof of the shroud. Mebbe!  ;)


The finger? Sunday joint carving, while Mrs. Drillin was also, in her kitchen......... :facepalm:

David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline b.lindsey

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #16 on: December 06, 2015, 02:27:01 AM »
Sounds like a good reason to stay out of the kitchen and in the shop then  ::)

Bill

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #17 on: December 06, 2015, 02:07:54 PM »
Heading the right way, I think...... 

Slow running test..........

<a href="http://www.youtube.com/watch?v=GRAuL-i8RQ4" target="_blank">http://www.youtube.com/watch?v=GRAuL-i8RQ4</a>


Going to shorten the verticals by 1/4".

David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline b.lindsey

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #18 on: December 06, 2015, 02:13:24 PM »
Definitely headed the right way David. I didn't time it but that seems to be close to the 150 rpm you were looking for. Thanks for posting the video!!

Bill

Offline fumopuc

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #19 on: December 06, 2015, 06:53:53 PM »
These are the slow pops I do like very much. Sounds good.
Kind Regards
Achim

Offline Roger B

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #20 on: December 06, 2015, 07:15:01 PM »
That's some interesting R&D work  :ThumbsUp:  :ThumbsUp: The last video looks and sounds good  :praise2:
Best regards

Roger

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #21 on: December 08, 2015, 08:06:53 PM »
Bill, Achim, Roger,
 Thanks for your kind comments!

Here, is the finished gas conversion.

Tank, held by single, knurled retaining nut......




The assembly, is held between the wooden rails. Enabling it to slide, as necessary........




Just noticed, in the last pic. I've forgotten to pickle n polish the burner!  :facepalm:

Don't suppose, anyone will notice........  :ShakeHead:

David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline Don1966

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #22 on: December 08, 2015, 09:46:54 PM »
Nice bit of engineering Dave. I do like the idea of running it on propane......... :cheers:

Don

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #23 on: December 09, 2015, 10:56:36 AM »
Thank you, Don.
 Must admit, it is very convenient now. Turn on the gas. Apply flame. Spin the wheel. Anytime.......  :)


Just made a batch of shutters.

They don't like, (relatively), high revs. The operating arm, tears the 5thou brass. But, only on the down stroke.......  :headscratch:

Background, templates. Centre, new stock. Foreground, oval holes........




I've ordered some 4mm brass washers. Going to solder one, surrounding the hole. 


David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline Roger B

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #24 on: December 09, 2015, 11:19:50 AM »
Tearing on the down stroke makes sense as that is when the shutter is being pressed against the cylinder head and there will be the most friction (I think  :headscratch: )
Best regards

Roger

Offline Ian S C

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #25 on: December 09, 2015, 11:25:55 AM »
I made the shutter for my motor from cast iron, it's .040" thick, and lapped to the valve face, it's survived so far .
Could it be that the brass softens as it heats up,  maybe some stainless steel would be better, or some cast iron.
Ian S C
« Last Edit: December 09, 2015, 11:30:06 AM by Ian S C »

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #26 on: December 13, 2015, 11:11:38 PM »
Nice start on the conversion David. How long do you think it will run on the gas before having to refill the tank?
Bill

The answer to that, is 5 hours, Bill!  ;)

The Robinson, with same volume tank. Was still running, some 3/4 hour later......  :o

David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline b.lindsey

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #27 on: December 14, 2015, 12:49:43 AM »
That's quite an improvement over the meths burner then. Well done!!

Bill

Offline Stilldrillin

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #28 on: January 15, 2016, 08:46:58 PM »
When I drill the 4mm. shutter hole, on a piece of hardwood, a rollover is formed. Just the right size for a 4mm washer.

Flatted to clear underside of the cyl. head........




Had some soldering problems, with the protective varnish. Got there, in the end........




A quick video, of a fast proving run........

<a href="http://www.youtube.com/watch?v=eR5DQYxWwJU" target="_blank">http://www.youtube.com/watch?v=eR5DQYxWwJU</a>



Shutters. Two on left, after a few seconds at speed. Third one after 6 hrs gentle running. Fourth one after several minutes at speed.....




I reckon, that's a success!

David.
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline Don1966

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Re: Gas Firing the Scott Vacuum Engine..........
« Reply #29 on: January 15, 2016, 09:46:14 PM »
That's some awesome results Dave and I loved the video......... :ThumbsUp:

Don