7mm SECR P Class

[phileakins]

On the basis that if I keep on talking about it I might actually do it, here is the start of my kit bashing (literally by the looks of it) thread.

I bough the etched kit fully intending to produce a working model in short order.  Several years later I found the box, with the un-started etches, at the bottom of a draw and though I'd better do something with it.  Big mistake.

Back into the draw with the now started and bungled effort - only to be resurrected and dismantled when the  next fit of enthusiasm struck.  Actually got a rolling chassis this time, but then I decided that I wanted to spring it ....... The draw received the now non-rolling chassis together with a motor/gearbox combination which sounded like a class 37 at full chat.

So, third time lucky? I've now got to scratch build the frames to S7 standards and ready for the appropriate working valve gear when it becomes available, which means that I need a scale drawing.

I have a set of GA's from the BR/OPC collection at York of the first two locos built, but they are different in a couple of important respects from the main production run, and of course the kit is of the later loco's. 

So, here is the Plan. Firstly, out with the trusty TurboCAD and prepare a frame drawing.  Secondly use what I can of the remains of the kit as patterns for new parts where the originals can't, for whatever reason (and there are several!) be used.

Third, glue it all together with molten metal to a reasonable standard. 

Sounds so simple don't it. 

Now, where is that box ........  Blast, the draw's stuck.

Phil

 

[Ressaldar]

Hi Phil,

built one several years ago, without putting it back into the drawer - mind you, it was one of the first and served it's purpose on the learning curve - often thought of doing another - one day [erhaps.

Best of luck with the build.

regards

Mike

 

[phileakins]

Just a bit bit of an update -

I'm using the layering facility of the CAD software to draw the frames and the 'gubbins' between, grouping components as  major sub-assemblies (ie springs/axle boxes, brake connections and rigging, cylinders and crossheads, valve gear, reversing gear and so on) so that parts can be easily drawn in situ, then 'turned off' to enable the next layer to be drawn on top without the complication of the earlier parts being visible.  This also mean that layers can be printed in isolation in their correct relative positions and to the correct size, or in any combination thereof.

Slow progress but it's coming on.  I'm finding the software easier to use as I go on, but there are still a lot of "Why the bl**dy hell won't it ....?" when in fact it would if I just took a moment out to read the manual!

My purpose built railway room is complete but the builder says that I can't move in for a month as everything needs to dry out, so practical progress will have to wait for a bit.

Phil

 

[28ten]

Just a bit bit of an update -
when in fact it would if I just took a moment out to read the manual!


Phil

Thats where you went wrong  I find manuals confuse me even more  or maybe thats just me..

 

[phileakins]

Hi Guv.

I've found that with CAD (as with Templot) there ain't no easy way. It's learn what the jargon means and then see how to achieve it, bit by bit in my case.  They're both rather (very?) 'non-intuitive' programs but powerful as hell when you master them (which I ain't - in both cases - especially Templot much as I love it)!

I suppose that, having got some drawings in hand, I should really start thinking about etching - I'll try by hand first though.

Phil

 

[Eastsidepilot]

Phil,
I not up on SECR loco's, I'm assuming this loco is stephenson link valve gear/motion?.
I will look forward with interest at this post mate, as I'm toying with scratch building motion for my GER/LNER J67/68 & 69 tanks that are waiting in boxes on the shelf : 
I'm with you on the Templot, just upgraded my copy, but still haven't mastered it after all the time I've had it.
Col. 

 

[phileakins]

Phil,
I not up on SECR loco's, I'm assuming this loco is stephenson link valve gear/motion?.
I will look forward with interest at this post mate, as I'm toying with scratch building motion for my GER/LNER J67/68 & 69 tanks that are waiting in boxes on the shelf : 
I'm with you on the Templot, just upgraded my copy, but still haven't mastered it after all the time I've had it.
Col.

Hi Col

Yes - it's got Stephenson's motion.  I've done the reversing gear and eccentrics in elevation, about to start on the crosshead and rodding, then the plan view.

Here's the valve gear so far.  I'm using a GA of the first two built - 753/4 which had lever reversing to start with (which makes them a bit more interesting).

First up the eccentrics and guides, then the reversing arrangement at the front end and finally the reverser and linkage:

 

[phileakins]

Got reminded today that tomorrow's the wedding anniversary. Ooops!  ;D  Well, if it ain't on the calendar I need reminding - so it's not my fault ...... And we haven't got a handy garage with flowers and chocolates either.  ???

Anyway, here's the slide bar/crosshead/con rod assembly with the corrected front end.  As it says in the manual 'you only need to draw it once', which might be true, if you get it right first time.  :

The big end is a bit of a guess (there is no elevation on the drawing) and is based on a plan view and a dull photo of the relevant part of a Bluebell loco, which, of course, is different, together with a bit of a drawing from Martin Evan's valve gear book.

[attachimg=1]

And - I've spelled Stevenson correctly this time.

Anyone got a big end drawing?

Phil

[Edit] Egg on face time - it is Stephenson  :-[ [/Edit]