1802 Bell Crank Engine

[b.lindsey]

That's an interesting video and quite a system with great looking results. So what it the mixture applied and how is it colored?

Bill

[Jo]

Thanks Bob & Phil  ,

Bill, The mixture is their own concoction, it comes self coloured for various purposes. It has fine sand in it, which makes it interesting to lay and it has some sort of (Acrylic?) chemical base as it goes off rock hard and I suspect is going to be very durable. 

I was looking at buying the mini real bricks and making the sides of the plinth out of those but had concern about getting my rows true and even.  And they are not cheap either 

I have used less than 1/8th of each packet of brick/block powder so I have plenty for any other engines I might want to make so other than the risk of it going off in the packet it looks to be good value for money  .

Jo

[Marty Feldman]

This excellent thread plus a recent kind PM from Jo have lead me to make a start on my Bruce Engineering casting set for the B&W 1802 engine.  The first chips are now coming off the cistern.  It appears that the most recent contribution to the thread was almost two years ago, so it is isn't clear how appropriate it is to resurrect it with questions, but I thought I might send up a trial balloon:  I would be interested in hearing comments on the ratonale for having paired steam inlets to the cylinder, rather than just one.  In one version of the engine model I have seen, the steam-in line is bifurcated with one branch to each of the two inlet flanges.  In another, one of the two inlet flanges is just covered with a blanking plate.

-Marty-

[Jasonb]

I have done a couple of engines with more than one inlet on the casting, often one is more suited to the specific site installation and the other simply blanked off.

I did actually see this engine today when Jo enticed me down to hers

[Marty Feldman]

Thanks for your sensible sounding comment.  I was afraid that I had missed some tricky essential about steam admission.

-Marty-

[Jo]

Having been told I was not allowed any more castings until I had finished at least the Stuart No 1 and it is going to be another 2 weeks until I can get the specified blue steel I had a look around the workshop for other things to play with, like repairing the workbench  ... when I re-found the Bell Crank Engine.  I had nearly finished it  but wasn't there was a couple of tricky/boring bits to go 

The first for finishing was the chute from the condenser pump into cistern. It had already been bent up but required the hole made in the side of the pump and joining together. The hole was roughed out using H and finished by hand filing. The two parts were soft soldered and then the joint first fettled and then finished by drawing a scalpel along the solder joint. It did not come out bad 

I now need to explore the situation with the rest of the engine. And there are lots of fiddly fixings to make 

Jo

[AOG]

I’m glad you’re working on this again Jo. I remember avidly watching this build when I first got started on this forum. I look forward to seeing it’s completion.

Tony

[scc]

Thanks for the "brick" info Jo.     I've settled in for this engine              Terry

[Jo]

  I remember why I got annoyed with this engine: The Square nuts and bolts do not fit the engine as described in the drawings  And most of the time they look much too big 

At this point I reviewed my pics of other models to find no one not even Anthony did not use square nuts on his engine 


So I am going back to what is  found on the  original Bell Crank Engine and doing a mixture of hex and square 

Jo

[Jasonb]

They do look a bit big, what did you base the sizes on?

I tend to go 1.5-1.6D for the AF

[sco]

Lap engine in the Science museum might be a good reference for what the fasteners should look like:

http://collection.sciencemuseum.org.uk/objects/co50948/rotative-steam-engine-by-boulton-and-watt-1788-beam-engines

Simon.

[Jo]

They do look a bit big, what did you base the sizes on?

  I thought I mentioned in my previous post they are the sizes Anthony quoted on his drawings.


Thanks Simon, the science museum also has a bell crank engine which has a mixture of hex and square fixings which is what I am now doing 

Jo

[Jasonb]

Just looked at the article and they are around 2D, hope you did not make all 80 of the small ones before finding they were too big

[Jo]

Just looked at the article and they are around 2D, hope you did not make all 80 of the small ones before finding they were too big

 

[Jo]

This is a fiddly one to put together 

And I am surprised on just how much movement there is on the bell crank 

Jo