Benson's Vertical Steam Engine

[J.L.]

My second model engineering project will be William Benson's vertical steam engine designed by Anthony Mount and distributed in England by Polly Model Engineering. They make excellent stationary engine kits.

In this picture I am holding the entablature cast in gun metal. This vertical engine will be presented only as a display model.

As with Stuart's 'Victoria' horizontal engine, I am calling upon a professional machinist to help me with items beyond my skill level or the capabilities of my equipment.

 I've had a crack at making a vertical engine before - in paper. These pics show a modified Bertschy engine where the cylinder is at the top. Benson's cylinder will be located at the bottom on the base.

The paper model was fun to modify. A basement was built under the platform to power it electrically.

[derekwarner]

Hullo John........

An interesting engine....however I do not understand the representation of the hexagon images for bolts?? 

Derek

[10KPete]

The model is made from paper....

Pete

[derekwarner]

Thanks Pete....

I saw the words.... "The paper model was fun to modify" ....but did not realise such a structure could be produced from paper and maintain shape considering 

Derek

[10KPete]

I had no idea such thing were being made of paper until JLs early posts on his machine shop diorama, in which he mentioned that the diorama started out on a German paper modeling site. If you go back to his early post you can find the link to that site if I recall.... amazing stuff being done!!

Pete

[Ramon Wilson]

Hi Pete - just looked in here for the first time. You must have missed this some time back -http://www.modelenginemaker.com/index.php/topic,1815.msg26814.html#msg26814

'Paper modelling' can be very impressive despite the medium and as you say some amazing stuff done by those who concentrate on it.

Good Luck with your 'Benson' John, a very nice little engine indeed

Regards - Ramon

[J.L.]

Thanks for the comments and good wishes gentlemen.

Derek, I was totally into paper card modelling for quite a while.  I downloaded the paper engine and printed it out with an ink jet printer, but when I began making it, I realized that to be more robust and durable, the parts should be reinforced. Wood and even old Meccano parts came into play. The desire to make a steam engine totally from metal had begun. 

[10KPete]

So, it really did start on paper!!   

Pete

[J.L.]

Hi Pete,
Yes indeed.

Benson's engine begins with the working up of a rather elegant casting in gunmetal. At first, I thought I could simply place it on the milling machine and fly cut the base flat. However, parts of this base have to be turned, so I abandoned the setup shown in the first two pictures and went with a wooden baseplate mounted on the lathe faceplate.

[J.L.]

The base was off centre a bit, but not enough to require counterbalancing. You will note that the larger boss is centred. When I remounted the base so that the smaller boss was centred, I hand rotated the wooden disk on the lathe and heard a 'cluck"! 

My lathe does not have enough swing to clear the base off centre. What to do?

The answer was to abandon the lathe and machine the smaller boss on a rotary table on the milling machine.    Pictures of that coming...

[J.L.]

The base could not be mounted on my lathe so it was off to the milling machine to use the rotary table.

[J.L.]

The rotary table also came in very handy in locating and drilling the many flange holes in the base.

[J.L.]

The bottom of the base looks like a piece of Swiss cheese, but the countersunk holes will allow bolts to be used as studs.

[J.L.]

The gunmetal base just completed is heavy, but will not have a wide enough stance to stabilize the engine when running. A wooden one was turned on the lathe and loaded with a heavy metal disk.

[J.L.]

Christmas Eve, 2016 

This week I received a phone call from the machine shop informing me that the column for the vertical engine was ready to pick up. I make no apology for having this solid 1 1/2" round bar of mild steel machined for me. It was so far above my pay grade. 

The machinist was very proud of the part and took time to explain how many points were plotted into the computer to create a program that allowed it to be cut with a CNC machine. I think I understood about one word in a score.

It is a beautiful piece of work. Too bad it has to be painted. It looked so pretty in shining steel. Apparently the column on the display machine that William Benson sent to London was unpainted and polished. Of course it was going to be seen by many at the exhibition.

I can only assume that the many workhorse models used in the mines and dockyards were painted to prevent rust.