Stothert and Pitt in 1/6th (and other) scales

[Stuart]

Thanks for the info Jo

[Jo]

I started by looking to remount the arms onto the entablature, the arms were clamped in place and the clearance drill for the 8BA bolts used to mark where the holes had to go:



Then drill and tap the holes:



It has now been primed so I have to move onto other things..

The reach rod is not raising up any  more:

<a href="https://www.youtube.com/watch?v=51bOD1abx-s" target="_blank">http://www.youtube.com/watch?v=51bOD1abx-s</a>

But something is not lining up so there is more fiddling to do 

Jo

[jonel]

Jo:

As you recommended I purchased the issues of Engineering in Miniature  (Nov 2002 thru July 2003)which covered the building of this engine by A Mount.  Unfortunately I did not get the Aug 2003 issue with the supplemental article in which he described in detail the fabrication of the flywheel.  Its impractical to purchase one issue and ship it to the USA so I guess the question is did he fabricate the flywheel similarly to the description you gave to Stew with a one piece machined hub or use a split hub design?   

Thanks for any assistance 

Jon

[Jo]

Hi Jon,

In the original article he talked about using a bronze casting and fitting a iron band to make it look like it was a CI casting. Following the series, I guess in the issue you identified, he described making a built up flywheel in exactly the way I made mine 

Good Luck 

Jo

[metalmudler]

Hey Jo, 

That's coming along great and is nicely detailed.
My kit came with a plasma cut steel ring from plate steel, which was mounted 'no pun' to my faceplate, given the warmth from a blow torch while the machined flywheel was in the freezer, then bammo. I know you built your flywheel from scratch,top job on it!   
This whole build is... Well... Just ace !

Paul

[Jo]

The motion is together, still rubbing in places. Mid position



Top position:



Bottom position:



Not easy to turn the flywheel and hold the camera with one the other hand:

<a href="https://www.youtube.com/watch?v=29Bv2RKQyEo" target="_blank">http://www.youtube.com/watch?v=29Bv2RKQyEo</a>

The eccentric rod is still clicking 

Jo

[Jasonb]

I'll bring a nice big 12" file with me at the weekend and sort out where its catching for you

[steam guy willy]

Jo, I looked at the video and noticed that in the down position, the motion moves to the the right  much more than moving to the left in the up position. I found the same on my little engine, is this an optical illusion or just the geometry playing tricks ? good to see the engine looking spic and span. 

[Jo]

Willy,

On the full sized engine the motion remains nearly vertical so something is not the right length/in line.

Jo

[Jasonb]

Yes they look to me moving a lot, Just dusted of my Stuart beam and there is vertually no movement to the vertical links - maybe 1 or 2 degrees.

When your beam is horizontal are the four horizontal links in the motion also horizontal?



Regarding the valve linkage jumping, how freely do the valve links and rod move? if they are a bit tight it may be causing too much drag on the eccentric rod

[Jasonb]

Jo back on page 76 you made a jig for the horizontal links to place the ends 60mm apart, double the drawing would be 58mm (2x29) could they be too long?

J

[Jo]

Could be but I am not pulling it apart again this side of the show, I've got a boiler to define the final details for 

Jo

[steam guy willy]

Jo, I'm sure the linkage measurements are 100% correct. I did notice this on my linkages and commented about it on my June 18 th post as being noticeable, so i think it is just due to the geometry that was available in Mr S&P's drawing office 180 odd years ago !!
willy.

[steam guy willy]

Could be but I am not pulling it apart again this side of the show, I've got a boiler to define the final details for 

Jo

Jo, will you be "showing " at the Midlands show, or is this somewhere else ?
Regards
William.

[Jo]

That was at Guildford, but it seems that someone is  trying to encourage me to enter it for a certain Sandown show.

It can't go yet I still have 4 "engraved" plates to sort out 

Jo