Penrhos Grange by Neville Evans

[terence nearyParticipant @terenceneary25426]

I am currently making a 5" gauge Penrhos Grange deesigned by Neville Evans.

A number of drawing errors have become evident. Is nayone else attempting this model?

[terence nearyParticipant @terenceneary25426]

I am currently making a 5" gauge Penrhos Grange deesigned by Neville Evans.

A number of drawing errors have become evident. Is nayone else attempting this model?

[terence nearyParticipant @terenceneary25426]

Drawing errors

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Hi Terence ,

I was a close friend of Neville Evans and followed his design process for Penrhos Grange closely and sometimes contributed a few thoughts of my own .

There were not that many known errors in the drawings but the ones that were found were reported informally to Polly Model Engineering the drawing and casting suppliers for the design .

They are a nice bunch of people and I'm sure they could help you .

Regards ,

Michael Williams .

[terence nearyParticipant @terenceneary25426]

‘afternoon Michael,

Thanks for the e-mail, I am in touch with Pete Thomas at Polly regarding the Penrhos Grange. However, I know how long things can take especially when you’re are running a business.

I am in no way criticising Neville Evans design I just thought I would alert any other prospective builder to the errors I have found during making the Grange. Most of them a minor but even so can lead to frustration if discovered after a part has be made to drawing. I am working to a combination of the ME articles and the Polly Issued drawings.

I will starting posting in the near future

Regards

Terry

[terence nearyParticipant @terenceneary25426]

Taking the Polly Model Engineering Sheet Numbers or Description in the order in which I made the parts

Sheet 3 :-

Spring Buckle: The 0.149 dimension should be 0.156 minimum to match the radius on the spring Link

Axle box suspension Bracket: The lug is not positioned side ways. It should be positioned to match the hole in the keep plate i.e the centre line of the lug should be .309" from the upper edge

Sheet 10 Valve Gear

Roller die Block: R0.819 should be 4.625

Rocking lever: INA Bearing should be SCE 2-1/2-4

Crosshead link: Diameter 0.125 should be 3/16" to match pin

Crosshead: should incorporate 3/16" Phospor bronze bush.

Sheet 11 Valve Gear Parts & Layout

Eccentric Rods: Upper Rod needs csk pin to avoid fouling Suspension lever bracket..

Weighshaft: Dimension missing, distance between centres of lifting links = 1.431"

More to follow

[terence nearyParticipant @terenceneary25426]

Valve gear.

Rod Valve: Distance between Hole centres should be 6.882" not 6.682"

Cross head Link: I advise making distance between centres 1.995 not 2.095 to give more flexibilty in setting length of the Piston Valve Rod.

Reverser body

View at left hand side of drawing (forward face) 0.281 dia Hole should be 0.25 Dia to match bush.

Plan view on scale is pictorially wrong since pin is in the centre of the nut and will not reach the extreme ends of the scale as shown.

Stays, Stretchers & Splashers.

E) Front Main Stay: Vertical dimesion of Valve rod Should be increased from 1" to 1.25"

More to follow

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