I faced the same choice a few years ago and am now building a 4” Samson. Totally delighted with the choice. As mentioned above, the original prototype was small so when buying fittings for the 4” Samson you will be in the 3” section of most catalogues.

 Every component on the 4” (including boiler, but not the whole engine of course!) is still a one-person lift. Makes life easier in the home workshop.

 Finished engine and driving trailer can be towed on a 750Kg unbraked trailer with a decent safety margin. Helps, keep the costs down.

Rob

Where did you ask on TT, I can't see it. Edward George (littlesamson) is a regular there and would have answered as well as the couple of members who have/are building the 6". If you e-mail edward who owns little samson I'm sure he will help as hes a nice guy.

I would suggest you get the back issues of ME that had the build in them and also a copy of Edwards book plus either read up Dave's builds on TT or get his "dream come true" books from e-bay. They show lots of machining setups and describe the builds in detail

Rear wheels are 29" over the strakes if you opt to turn teh cast ones. If you go with the more traditional wheels then the rims can be rolled and welded so no need to have such large turning capacity. The 3" scale fronts are 9" so about 18" on the 6"

3" flywheel is also 9" so you would be looking at approx 18" on the larger engine.

Don't have the gear size but the final drives are usually about teh same size as the flywheel

Hi.

I built my 4" little Samson using a Boxford CUD 4.5" and a VTM mill. The only thing I could not manage was fly cutting the saddle on the cylinder block, my local engineer did it for me for a few euros.

I have a gravel drive and the metal rims were not too happy, it was not too keen on wet grass either but I do have a problem with moles and the surface is not too flat.

You could try the 4" Foster by Live Steam Models of Derby. It is a bit bigger than the 4" LS but makes a stunning worker. A French guy has one and he works it all day pulling kids around the showgrounds. I have a mint set of drawings for this model going cheap if anyone is interested.

I have just completed the 6" Little Samson, took me 13 months to build. I bought a Bridgeport J Head mill with power feeds and DRO, perfect for the job. I have a Chinese lathe which took the 18" dia flywheel with the leadscrew taken out (must put it back sometime). I got the gears cut by John England of Bradford West Yorkshire. He did a good job and the price was right. He machined the blanks and did the gear cutting for just over £400.

There are photos of both my engines on Edwards website plus a stunning photo of me.

Regards.

Roger. ScruffyB