Paddleducks

Other Marine Models => Live steam => Topic started by: Peter Webster on August 10, 2008, 02:44:45 PM

Title: VR1A Steam Engine
Post by: Peter Webster on August 10, 2008, 02:44:45 PM
I need some advice re this engine . Can you reverse it without stopping the engine and what size boiler would I need to make to get about 10 minutes running time. The boiler will be a simple kettle type as the engine apparently runs on about 10psi once run in.
Peter Webster
Title: Re: VR1A Steam Engine
Post by: Eddy Matthews on August 10, 2008, 03:42:49 PM
I'm afraid I cannot answer your questions Peter, but for those that can, here's a link to the engine Peter is talking about:

http://www.grahamind.com/vr1a.html

It's a Single cylinder, double-acting, reversing (Stephenson gear) steam engine.

Eddy
Title: Re: VR1A Steam Engine
Post by: derekwarner_decoy on August 10, 2008, 07:23:03 PM
Hi PD's.... :thinking...one should let the engine to be at ZERO revolutions prior to engaging the reversing gear.......but the (Stephenson gear) is not mechanically linked....but just by reversing the pressure acting on the mating components

When we look at the depiction of the engine room in the Titanic....it is clear the engine was given a telegraph reversal signal.......

I think.... Bandit.....Vinnie :whistle :ranting :towel or bogstandard could offer the best qualified comment here...........Derek

 :sorry...........we also have Nick from Monahan Steam...who may wish to offer comment.......

Running time = P1xV1xT1...multiplied by Boyles & Charles Laws  = ?.......we have discussed this in previous postings  :hehe :nahnah ::ranting
Title: Re: VR1A Steam Engine
Post by: bogstandard on August 11, 2008, 12:47:05 AM
Never having had anything to do with this sort of engine, I cannot give a qualified comment. Maybe Bandit could, but he's taken an oath of silence for a while.

Looking at it logically, because of only a single cylinder, I would suspect that if the engine was reversed while it was in a certain position, and stopped, it would have to have a physical pushover to get it running again. But on the other hand, I have seen linkage controlled engines swapped over when running.

If you come back again next year I might be able to answer your question, I will be making one then.

Maybe an email to the manufacturer could answer all your questions.

Sorry not much positive info.

John
Title: Re: VR1A Steam Engine
Post by: kiwimodeller on August 11, 2008, 08:09:42 PM
Peter, while not familiar with this particular engine it is my experience that any single cylinder cannot be relied on to keep going if slowede right down or stopped to reverse it however there are ways around this such as fitting an auxillary electric motor operated by a micro switch to spin the motor to restart it. I have even heard of the electric motor being used to get the boat home when the flame went out. Nothing is impossible, it is just a matter of whether it is worth the trouble. Cheers, Ian.