PM Research 8M V-twin

[aussiebrj]

Hi PD's..  looking to build one of these V-twin engines, but not sure of the capability of this to drive a 36" Paddler geared down. 
Have any of you used this in a vessel and if so what are your thoughts?

Really appreciate any help - this is really new to me.

Bruce from sunny Queensland   

[derekwarner_decoy]

Hi PD' s......    ...Bruce...here is a build site for a  PM Research 8M V twin.......

http://www.google.com/url?sa=t&source=web&cd=2&ved=0CCAQFjAB&url=http%3A%2F%2Fmodelsteam.myfreeforum.org%2Farchive%2Fpm-research-8m-v-twin__o_t__t_41179.html&ei=lfJOTpztDoOPmQXAiaXOBg&usg=AFQjCNFn-sCQpPKqcN0K7jaf0W9xe4XL9g&sig2=71JVE7Zk5C6449l9ZXlC1g

I have no experience with the engines....but possibly Peter Webster    from Melbourne........[he has posted today] may be able to assist

One aspect of steam... ...is that why hide the engine & boiler & bits?....polish the brass/copper ....lag the boiler & show the world......

Try GOOGLE for as much information on the PM Research 8M V twin engine......... it would appear that they will run happily @ 2000 RPM....& would certainly power a 3 ft model...........but  ...you must balance the design & cost of reducing this to a paddle shaft speed of say 20>..........100>150 RPM........ .....Derek

[aussiebrj]

Hi PD's       Derek thanks so much for the info. It was this link which actually got me interested in this little engine. I also like to fact that the reverse and throttle are incorporated in the engine.
As far as gearing down that is a challenge I will have to look into - have to put my former mechanical engineer's hat on           .........Bruce

[Peter Webster]

Bruce,
          You will have to realize that this engine pulls a lot of steam so a big boiler is called for. I think that it will have more than enough enough power for the intended boat but at 36ins as I was going to use one on a 54ins model of the Pevenseybut decided to use another engine. I do hope that the Paddler is going to be an Aussie type. Derek, I wish that site on the building of this engine was up when I built mine.
Peter W

[kiwimodeller]

Bruce, I have imported at least ten of these engines in to New Zealand and resold them. I have not had anybody say they are unhappy with them, in fact most people rave about how well they go and they are very good value for the price. As far as I know none have been fitted to a paddler so far but I am going to use two of the single cylinder engines (so effectively the same engine) in my 52" sternwheeler and I am confident it will have enough power. I fitted a V Twin to a friends 45" Steam Yacht Tender (and he is still a friend!) and it turned a much bigger prop than any of us thought it would. As Peter says it needs a reasonable volume of steam but it does not need high pressures, 40PSI is plenty. My friends boat has a 6" tall by 4" diameter vertical boiler and I would reccomend a 4" diameter horizontal for the volume which might be a bit big for a 36" boat. If you need to use a 3" diameter boiler it will probably need to be at least 7" long and preferably more. I would be looking to put it in a bit larger hull, say 42 to 48" which would then have plenty of room for a decent size boiler. Depending on paddlewheel size I think you would need a reduction of around 4 to 1. Hope this helps, Ian.

[aussiebrj]

Hi PD's .... Ian thank you so much for your info. As a newbie I really appreciate any guidance. I was thinking of a 4" dia horizontal boiler - self made, and as you said these engines appear to be really good value for money. I'll keep everyone posted.

Peter, I am considering an Aussie - still looking as they say. Regards to all, Bruce.