Stuart Victoria Query

[Clive Brown 1Participant @clivebrown1]

I'm just starting to build a Stuart Victoria engine.On examining the drawngs, I'm slightly surprised that the crankshaft is positioned 1/4" above the cylinder centre-line. Does this height difference have a noticeable effect on the running of the engine, eg a slightly uneven exhaust beat. Do any other Stuart horizontals have this feature? Just curious.

Clive

[Clive Brown 1Participant @clivebrown1]

[JasonBModerator @jasonb]

Should not be. The ctr height of the hole in the main bearings is 5/8" from bottom. (wrong on the 1993 drawings) The ctr line of the holes in the cylinder support brackets are 5/8" from bottom and adding up the various bits of the cross head guide put the cross head pin 5/8 up. 

Horizontal green ctr line runs straight through all three points

You may want to have a look at this thread where depending on what drawings and or book you are working from there are errors, I'll going to post a set of corrected drawings soon if you can wait.

Edited By JasonB on 18/04/2021 17:16:14

Edited By JasonB on 18/04/2021 17:21:42

[Clive Brown 1Participant @clivebrown1]

Thanks Jason. I have the 1993 drawings. I had read the linked thread where discrepancies were pointed out but these seemed to relate to the longitudinal positions of the cylinder, slide-bars etc. I've fabricated the bed and was intending to measure up as the job progressed and make items such as the con-rod to suit. However, my drawing clearly dimensions the main bearings at 7/8" above the bed compared with the cylinder at 5/8". Scaling off the drawings also confirms these figures, the draughtsperson must have been having a bad day. I'll make my bearings 5/8" as you advise.

I await your corrected drawings with interest.

PS.I wonder how many Victorias have been made with the height difference?

Edited By Clive Brown 1 on 18/04/2021 18:44:54

[Steve WithnellParticipant @stevewithnell34426]

Mine certainly has! It's not getting rebuilt now…

Victoria

You can hear the big end knocking, that I will fix one day Usual shortage of 'roundtuits'.

Steve

[duncan webster 1Participant @duncanwebster1]

Lots of GWR locos had the cylinder centre line above the axle centre line, didn't seem to bother them over much. Makes valve timing a bit different, but Steve's video shows it doesn't matter much

[JasonBModerator @jasonb]

I think the problem was a bit of early cut & paste when the '93 drawings were done and a few bits from the beam got copied rather than having the subtle alterations done for the Vic.

I've a set of castings for a smaller ball hopper engine that like the full size has an offset crankshaft.

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