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Eastern and Anderson Grasshopper Beam Engine

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Jo:
This last weekend I have just finished off my Eastern and Anderson Grasshopper Beam Engine, which had for many years sat on my book shelves looking rather sad:



In the main the castings were no problem to machine, what stopped the original build was the need to make a number of long thin spindly items which having attempted a number of times I made the decision that I was not ready for. Time moved on and now the parts have been completed. The tricky spindly bits included such joys as a connecting link 2 ?? long and only 2.4mm diameter:



These were actually cut on my Cowells Lathe between centres, the bearings and end caps being made as turned disc which were super glued to the main link before putting in a machine vice and the faces machined flat and holes drilled/reamed using the DRO to get the lengths correct. 

Another tricky bit was some 1/16? dia valve links. In the end these proved fairly straight forward and all followed a similar process, so to give you an idea this is how I did these links:



Starting on my milling machine I used the DRO to accurately position the centres of the two holes before moving on to my BCA to mill the flats to width:



My Cowells Lathe made cutting the 1/16? shaft a breeze:





Next job was to turn shoulders on each of the faces:





Before a bit of hand filing using filing buttons, super glued in place during the filing operations. These are the resulting links (the photo was taken before polishing :facepalm:).



I?ve got a few more photo?s of making some of the other tricky bits if anyone is interested.

Jo

Bogstandard:
It is so nice to see you posting here Jo, I was looking forwards to seeing this engine finished off and running.

Like yourself, I find fiddly bits like this rather challenging, but it looks like your efforts really paid off this time.

John

Dan Rowe:
Hi Jo,
The small tricky bits are often the most interesting parts to see how to make. I would love to see the rest of the build photos.

Dan

Jo:
The governor was an interesting build:



Most of it is simple turning, for instance the main body is made simply from brass stock and consists of three parts silver soldered together, this cross section explains a lot of the make up:



However the Governor top was a tricky bit:



Originally I thought that I had lost the casting but on further investigation I found that it needed to be made from bar stock. The important thing to note is that this part requires to be threaded squarely with the governor body so it is necessary to first make the body, then taking a piece of ?? brass bar turn and thread it fit the governor body. Once screwed together both embryo cap and body are taken over to the mill and the cavity milled and the drive shaft spindle hole drilled.



The cap now goes back to the lathe and the cap is shaped up,


and the top taper was turned.



I now realised that I had missed a trick and took the cap back to the mill and squared up the cavity and a bit of careful filing to get the various curves looking better?.and then parted it off.  The cap was then turned around and the top drilled to take the cap and balls. The bearing for the drive shaft spindle was a simple brass turning silver soldered to the side of the cap.  This is the final cap in position on the governor body.  (Oops I forgot to take a photo after the drive shaft bearing had been solder on the side, sorry)





The weight arms were a bit of a cheat, I took three 3/16? ball bearings heated them up to soften them, made a simple arm similar to have the link I described earlier and then silver soldered them together.

The bevels were very simple as on this engine it is only a case of, as they say, making to balls go round, rather than controlling the engine. They were  made by first profiling 4 ends  (2 + 2 spare) of a bit of 8mm stainless to match the gear shape, then these were taken to the mill the dividing head set to the gear angle and then each tooth was cut using a piece of broken centre drill ground to a taper, the curves formed by hand so that the gears ran smoothly. Back to the lathe one gear was tapped 10Ba for the drive shaft and the second was drilled 2.4mm for the vertical column:



The parting off of the gears was done on the Cowells using its Sherline 4 jaw self centring chuck.

Jo


Bogstandard:
Jo,

I am glad to see you make gears how I do.

Only sometimes do they need to be perfect, in which case, they would be purchased, most other times, as long as they run smoothly together, then they will do the job admirably.

I think that when beginners see gears in a build, it puts them off a bit, as they can sometimes be very expensive to buy, but with a little knowledge and patience, they can in fact fairly easily make their own, as Arnold is showing in his superb post.

http://www.modelenginemaker.com/index.php/topic,195.0.html

John

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