Self starting single d/a wobbler

[fcheslop]

For a lockdown project Im building a small steam boat designed by Vic Smeed named River Princess she is the smallest of the Wide Awake style of boat
I wanted to make the plant as simple as possible using a single cylinder engine. Normally they wont self start so this one has a kickstart built into the for/reverse and seems to be working reliably
The whole lot is been made from some of those little bits n bobs and some very old and dirty ply at least its keeping me busy
cheers
frazer

 

[ScottB]

I would be interested in seeing more detailed information on your self starting mechanism. Very Nice work!

Scott

 

[Brian Rupnow]

Fcheslop--that is a great idea. I haven't seen that done before. I know that some of the early steam powered Dories liked the motor to be reversible so they could back up, but in most single cylinder engines they let it stop and then started it in reverse.

 

[fcheslop]

Hi Scott, it is simply two pins on the back of the flywheel timed at Top Dead Centre and Bottom Dead Centre. As the the control valve moves from foreword to reverse a pin on the bottom of it contacts the flywheels pins pushing the engines cylinder past either TDC or BDC. It is not perfect and needs a little more tweaking as it can hit a position that locks the engine.Im going to make another pin with radiused sides and soft solder the valves ports then file to give a more gentle shut off . It needs to come to a stop with a little steam pressure or I should say it needs to stall the engine so that the pins are correctly aligned
Hi Brian thanks, the idea is not mine as it was in a Model Engineer in the 1930s and a French Company made a piston valved version although Iv noticed they have a similar problem to me.
The model will be radio controlled so Im trying not to get my feet wet ,all good fun though
Im going to get back on with it soon as Ive finished my version of the Rev Stirlings Glasgow engine
cheers

 

[dnalot]

As a retired boat builder I love seeing a beautiful hull. Especially when they are of lapstrake construction. My brother and I built the C-Dory line of boats, all with lapstrake hulls. Everything looks great, hope to see more when completed.

Mark T

 

[fcheslop]

Thanks Mark, I had a few problems with the hull as the planks did not want to go the way I wanted them to. If making it again I would add another two per side. She is made from scrap that has been laid around for 20 plus years and is just to get my hand back into building them again. The planks ended up a bit awry at the bow and a few joints are a bit gappy due to using scrap well thats my excuse . She is only 2ft long and it gets a bit awkward geralding 1/16 planks. Will have to do better on the Wide Awake build as she will be varnished . Iv always liked clinker hulls but never built a full size one. That must be a joy to build and actually sail in her.
Keep well and thanks again
frazer

 

[dnalot]

I had a few problems with the hull as the planks did not want to go the way I wanted them to

Soak your planks in 3 parts water to 1 part vegetable glycerin. it will make your planks more pliable. They will need to be dried before gluing. Apitong wood
is very weather resistant and works well for uses requiring fine detail. It looks like Mahogany. Yellow cedar is harder to find but is more workable. Both are prized by boatbuilders.


I only had to make the original hull from wood. After that they were made from fiberglass. It would take months to make the wood one. And a few weeks to build the molds from it. Once we had a mold we could cast one every two days, deck house and all, one piece.

Mark

 

[ScottB]

Hi Scott, it is simply two pins on the back of the flywheel timed at Top Dead Centre and Bottom Dead Centre.
cheers

Frazer, I have done the same on a single cylinder double acting engine. I did put two pins on what I called a "self Start Disc" and they are clocked at 12:00 and 6:00 positions when the piston is on either top or bottom dead center. I extender the throttle lever to engage the pins on the self start disk to push the engine off either top or bottom dead center. I have found that the radius on the end of the lever is very critical to a smooth push of the pins without binding.
Scott

 

[fcheslop]

Hi Mark, many thanks for the tip . For my small toys I use ammonia or if its small sectioned just a spray on window cleaner. I have a steam box made from a wallpaper stripper and a length of pipe . The planks on this wee boat are from 1/16 marine ply a bad choice on my part but all I had so cannot grumble about it
Just on carving a wee Puffer from some Yellow Pine she is bread and butter construction and is a bath tub job at 12 inches
Iv attached a video of the plant running
I have not build a model boat for a long time and the idea is to find out what I need tool wise as I no longer have a full woodworking shop to play in. My late father was a cabinet maker but after he passed away the shop was sold on.
So now on my build list is a small table saw, drum sander and a thicknesser. I kept some of the hand tools and can often hear the old man chewing my ear when using them.
Hi Scott, thanks for the rendering we are on similar lines although it looks like youre a good bit ahead of me. I will have another go at the arm as it is rough just a suck it and see job. Im sure I have seen youre engine recently on you tube?.
Thanks again for the info gentlemen its nice to hear how others get round problems and you never know another builder may find it of use

 

[ScottB]

Hi Scott, thanks for the rendering we are on similar lines although it looks like youre a good bit ahead of me. I will have another go at the arm as it is rough just a suck it and see job. Im sure I have seen youre engine recently on you tube?.

Frazer, Yes there was a video posted to you tube of my engine running some time ago. Is your engine a design of your own or built from plans. My engine was of my design.

Scott

 

[fcheslop]

Hi Scott, the engine is my own design .It is made from the junk pile and I would have done a few things differently if I had some better materials
The idea is to use up some of those bits n bobs lying around and just enjoy mucking about with a wee steam plant. Also I am clinically vulnerable so have spent most of the year locked in, unable to get to material suppliers and to tight to pay postage
My main interest are Stirling engines although these are now getting smaller as the stock sizes get smaller.
cheers