Tom Mallard’s Workbench L&B in 7mm scale, CR 828 in 7mm, GWR Saints in 4mm

[45609]

I'll come and have a look at it in the flesh on Saturday. That's assuming you'll have it with you?

 

[Tom Mallard]

I'll come and have a look at it in the flesh on Saturday. That's assuming you'll have it with you?

Yes, it will be with me. Hopefully fit to view...

 

[Len Cattley]

I will at Scaleforum on both days, where will you be Tom?

Len

 

[Tom Mallard]

I will at Scaleforum on both days, where will you be Tom?

Len

Hi Len,

I will mostly be assisting Martin Finney on the Locomotive Construction demonstration desk. See you there!

Tom

 

[Len Cattley]

 

[Tom Mallard]

I had a very busy time talking to other modellers at Scaleforum, and was surprised at the interest in the D15.

I have put the majority of the chassis together now, with just pickups and a few pipes remaining. It has ended up quite a busy place between the frames, but it all fits in and wiggles and whirls appropriately. Plenty of (invited) finger pushing at Scaleforum meant that the components are bedded in and proven too, after nothing came off...

The duplex pumps are screwed to small brackets that sit just above the lower edge of the valence and each casting was modified to represent the type fitted to the D15's. I machined off one of the manifolds and reinstated a more slender version nearer to the centre line of the model so that the rods could pass unimpinged as required.

I really should finish off the tender frames and loco bodywork now.

Best regards

Tom

 

[Steph Dale]

Tom,
Very impressive work, especially considering it's so tiny.
Can I just ask whether you had the Motion Arrangement drawing available to you? It's just that I'm not certain you've got the shape of the crank webs correct...
Steph

 

[Tom Mallard]

Tom,
Very impressive work, especially considering it's so tiny.
Can I just ask whether you had the Motion Arrangement drawing available to you? It's just that I'm not certain you've got the shape of the crank webs correct...
Steph

Are you having a laugh Steph?

No, they're not the correct profile (or width) as I was supplied with pre-existing castings from Martin Finney's range which do not correspond to those on the GA where they appear to be of a more simplistic arc ended profile. I wanted to maintain a straightforward build so kept them as is, though I feel I may still attend to this if my powers of reason get the better of me. In the past I have reprofiled the same cast crank webs and at the time I worried that their integrity could be compromised. Let's hope that with the body on that this flaw is largely invisible.

My scratchbuilt projects encourage more scrutiny.

Best regards

Tom

 

[Steph Dale]

I wish I was...

The cranks shown on the GA aren't right either; the notes panel on the drawing details (IIRC) the use of 'balanced' cranks. The ones you've fitted are absolutely fine for most of the locos with Stephenson valvegear after the S11 (and replacement crank axles) . Unfortunately the D15 had a very peculiar crank shape to balance out the Walschaerts motion.

The arc-ended cranks were a carry over from Adams era and used on the early Drummond locos. After the Urie rebuilding the larger 'balanced' cranks were fitted - the T9s particularly suffering a high failure rate of their original crank axles. As an aside the arc ended form remained in use on Eastleigh drawings as a symbol - even the LN drawings showing this style, which they definitely didn't have in reality.

Steph

 

[Tom Mallard]

I wish I was...

The cranks shown on the GA aren't right either; the notes panel on the drawing details (IIRC) the use of 'balanced' cranks. The ones you've fitted are absolutely fine for most of the locos with Stephenson valvegear after the S11 (and replacement crank axles) . Unfortunately the D15 had a very peculiar crank shape to balance out the Walschaerts motion.

The arc-ended cranks were a carry over from Adams era and used on the early Drummond locos. After the Urie rebuilding the larger 'balanced' cranks were fitted - the T9s particularly suffering a high failure rate of their original crank axles. As an aside the arc ended form remained in use on Eastleigh drawings as a symbol - even the LN drawings showing this style, which they definitely didn't have in reality.

Steph

Steph,

it seems the current cranks are the 'least bad' compared to copying the one on the GA, but it is irritating that no clear profile of the actual one is given. I wonder if it will be nearer in profile to the ones shown on the front coupled axle of the T14?

I skimmed the NRM Eastleigh drawing list and there are two drawings for D15 motion. If you secure a copy, please let me know your findings.

Best regards

Tom

 

[Steph Dale]

I've got a copy of the MA and it shows the cranks having a distinct dog-leg in their side profile, so not like the T14. I'll dig the info out this evening.

I had assumed you had the MA as you've made such a superb job of the motion bracket which isn't shown at all clearly on the GA.

Steph

 

[Tom Mallard]

I've got a copy of the MA and it shows the cranks having a distinct dog-leg in their side profile, so not like the T14. I'll dig the info out this evening.

I had assumed you had the MA as you've made such a superb job of the motion bracket which isn't shown at all clearly on the GA.

Steph

Thanks Steph.

I can read general arrangement drawings well, and aided by Martin's original design drawings, the etched components supplied went together logically though I accept they required a lot of careful fitting and assembly.

I look forward to having a look at the drawing.

Tom

 

[Steph Dale]

Tom,
Here you go - possibly the strangest bit of locomotive engineering I've ever seen...:
Note: This image is part of an original LSWR Eastleigh works drawing, Copyright of the National Railway Museum and reproduced here for research purposes only.

Steph

 

[ZiderHead]

Don't worry about copyright - there is none on engineering drawings, they are not Useful Articles under the law

Edit: If Drummond had added a doodle to the drawing, that part of it might be copyrightable as artwork, but that would have expired in 1982 anyway

 

[Tom Mallard]

Tom,
Here you go - possibly the strangest bit of locomotive engineering I've ever seen...:View attachment 48347
Note: This image is part of an original LSWR Eastleigh works drawing, Copyright of the National Railway Museum and reproduced here for research purposes only.

Steph

Thanks Steph for going to the trouble. Perhaps an Aboriginal design influence? What does the plan view look like, or is it not on the drawing?

 

[Steph Dale]

Don't worry about copyright - there is none on engineering drawings, they are not Useful Articles under the law

Edit: If Drummond had added a doodle to the drawing, that part of it might be copyrightable as artwork, but that would have expired in 1982 anyway

Hmm, well the NRM claim copyright...

Thanks Steph for going to the trouble. Perhaps an Aboriginal design influence? What does the plan view look like, or is it not on the drawing?

Tom,
Plan view is exactly as you have it in your model, I haven't flattened that part of the image yet though so it looks a bit distorted!:

Note: This image is part of an original LSWR Eastleigh works drawing, Copyright of the National Railway Museum and reproduced here for research purposes only.

Steph

 

[adrian]

Thanks for that - I was going to post a reply on that topic but will switch to your thread instead.

 

[Tom Mallard]

The D15 is pretty much done, bar running trials and the like. It will need some extra ballast I have no doubt.

As usual, the work bench emptied of bits, pieces and sub assemblies as the model finally came together - always a good feeling. This model proved quite time consuming to assemble all the layers of detail, with the inside motion being a small portion of this.

Best regards

Tom

 

[Locomodels]

Not a favourite prototype of mine, but what a superb model. I have thoroughly enjoyed your thread, thank you.

 

[Dikitriki]

Absolutely lovely

Richard