7mm Martin Finney 7mm Duchess

[Dikitriki]

Hi,

A bit of an indulgence this, as it's not Heyside related, but what the heck. It's a kit I have had for a number of years, another of my part-started bargain buys from a show. In fact little had been done (front footplate and bogie from memory) but what had, had been done pretty well. It still all got blow-torched apart, but it meant that every part was perfectly useable. I was fortunately able to find all the boxes in the chaotic mess of the room Heyside lives in, as it is just dumped after the Doncaster show.

The Duchess is one of my favourite locomotives, and I have 3 to do. A de-streamlined from an MMP kit which is slowly going through the paint shops (18 years and counting), this one which is non-streamlined, and a David Andrews kit for one of the last 2. I shall spend tonight going through the boxes and instructions to remind myself where I am up to, and finding all my research sources.

Tomorrow, I shall recommence work on the tender and take some photos of the tender chassis which is pretty far advanced. One thing I have to think about is the compensation.......in that I have made it with compensation, but I'm not convinced it's what I really want to do.

Richard

 

[mickoo]

Hi,

A bit of an indulgence this, as it's not Heyside related, but what the heck

Rule #1

The Duchess is one of my favourite locomotives, and I have 3 to do. A de-streamlined from an MMP kit which is slowly going through the paint shops (18 years and counting), this one which is non-streamlined, and a David Andrews kit for one of the last 2. I shall spend tonight going through the boxes and instructions to remind myself where I am up to, and finding all my research sources.

I've managed to keep my LMR lid on for some time now but this'll be interesting to watch.

.......in that I have made it with compensation, but I'm not convinced it's what I really want to do.

Richard

Of course you don't , equalising beams / compensation, whilst effective and overall easy to set up, are so 'Roman engineering' a Stanier engine requires a more elegant approach I feel

I'll guess it'll be BR green of which I am in favor, however over the years the BR maroon has rather grown on me

Mick D

 

[Heather Kay]

I've managed to keep my LMR lid on for some time now but this'll be interesting to watch.

Most certainly. Best Beloved and I had plans to build 46256 from the Andrews kit, along with 46203 from the same stable - first and last, as it were. However, for various reasons we sold the unstarted kits on. I have to say, I am a little jealous and will watch this build of a Big 'Un with interest.

 

[Dikitriki]

Hi,

I had a very pleasant evening last night going through my Duchess sources and getting back up to speed on the kit, working out why I had done what I had done; going through what's left in the box and looking at the options.

So, today is about the inner chassis. Martin designed the tender so that there is an inner chassis with the wheels, brake and scoop gear, an outer chassis with the axle boxes, springs, drag beam and buffer beam, and a body, which all screw together on final assembly. This makes it much easier to build as you are working on separate units which makes everything much more accessible. Indeed, the body is largely built out of separate units and only assembled at the last. It really is a tremendous model of the big Stanier tender. Naturally, there's a few areas where I go my own way, but if you just built it straight out of the box, you would end up with a model to be proud of.


Of note here are the outriggers that carry the transverse brackets. I have cut them back so that I can get the outer wheels out easily. You can see also that the top of the brake hangers are screwed in - I can remove all the break gear, necessary to drop the middle wheel. The rear axle is fixed, the front 2 are compensated and the central beam is visible. The kit doesn't give you a choice but to build it this way. However, I'd probably spring it if building another, but see later.






I have replaced all the brake spreaders and rodding with castings and wire. They are provided in the kit as a sandwich etch, but I do not believe such an approach can portray the true heft of the parts. These components came from Sanspareil.



The scoop and operating gear is fully modelled, and although I haven't finished it yet, so is the water diverter and the linkages.....excellent!



OK, here's the issue with the suspension. The kit is designed for the Slater's wheels for Finney kits, which in this case means a 5/32'' axle. Because the compensation is designed in, there are no bearings or hornguides for the leading 2 axles. Indeed, I do not think there is enough meat in the bearing area to fit after-market hornguides from any manufacturer. The only option I can come up with (other than to leave it as is) is to fit some 5/32'' bearings, maybe fixed on the leading axle and sprung on the middle, but I'm open to any bright ideas. I also think that with use, particularly on a continuous run layout, there will be necking on the axle as the bearing surface on the beam is small, which will entail some considerable maintenance issues in the future.







Richard

 

[Scale7JB]

Must not start my Finney kits - must not start my Finney kits...!

JB.

 

[Steph Dale]

Richard,
I had a look at my Finney Duchess tender a short while ago and I suspect that any of the brass/nickel-silver hornguides would fit just by notching the frame. Admittedly you won't have a full frame down the sides, but that might be an advantage as there wouldn't be much visible when assembled.
It would also be much easier to do if the frames were modified while flat rather than assembled!
Steph

 

[demu1037]

Hi,

OK, here's the issue with the suspension. The kit is designed for the Slater's wheels for Finney kits, which in this case means a 5/32'' axle. Because the compensation is designed in, there are no bearings or hornguides for the leading 2 axles. Indeed, I do not think there is enough meat in the bearing area to fit after-market hornguides from any manufacturer. The only option I can come up with (other than to leave it as is) is to fit some 5/32'' bearings, maybe fixed on the leading axle and sprung on the middle, but I'm open to any bright ideas. I also think that with use, particularly on a continuous run layout, there will be necking on the axle as the bearing surface on the beam is small, which will entail some considerable maintenance issues in the future.

Richard

Richard, 5/32 i/d tube on the axle & notch the beam accordingly?

 

[Cliff Williams]

Lovely kit!


I made mine come apart like this, it looks like you have found the same mods to be done as me. I would go for the 5/32 tube to cure your axle diameter issue.
Checking 46245 that has done quite a few miles it shows the least wear on the chassis compared to other locos, so it is standing the test of time - fourteen years now on and off.

 

[Dikitriki]

Steph,

I've had a look at the commercial hornguides/bearings, and I think you're right, I could - just -use them. I had a look at the Fourtrack/Meteor ones as I think they are the strongest and deepest, and also, marginally, have the narrowest hornblocks. They would have the greatest soldered surface at the top of the chassis. I would obviously need to use 'normal' Slater's wheels, but that's not a problem, at least for the leading axle. I can't see myself getting to the middle axle now, but I could get some long 5/32'' bearings (Slater's) and spring each side with wire for that axle. It's doable, but I can think about it for a while as no dismantlement of existing work is necessary.

Richard

 

[Dikitriki]

Richard, 5/32 i/d tube on the axle & notch the beam accordingly?

Thanks Andy, good suggestion. I could slieve both leading axles and treat the brass tube as sacrificial if it necks to the point of altering the ride height. It would be a bit of a pain to adjust the compensation beam accurately in situ though. It's on my list for Kettering.

Richard

 

[Dikitriki]

Cliff,

City of London looks beautiful. I am reassured by the lack of wear from the compensation beam.

Richard

 

[Steph Dale]

Richard,

Just a thought, but the small contact area of the brass doesn't necessarily mean high wear - but it definitely means low friction.
You might carry on as you are and use a good quality loaded lubricant (molybdenum or PTFE loaded greases are good at reducing wear).

Steph

 

[Dikitriki]

Richard,

Just a thought, but the small contact area of the brass doesn't necessarily mean high wear - but it definitely means low friction.
You might carry on as you are and use a good quality loaded lubricant (molybdenum or PTFE loaded greases are good at reducing wear).

Steph

Thanks, Steph,

Sounds a good interim solution. Do you have a source for such lubricants in the small quantities we require?

Richard

 

[Steph Dale]

Yep, I'll lob a pot of something in my bag for Kettering. I'll have to see what I've got!

Steph

 

[simond]

Steph,

Classic friction theory suggests that friction is independent of the (apparent) area of contact.
It only relates the load, and the coefficient of friction to give the friction force.

• Amontons' First Law: The force of friction is directly proportional to the applied load.
• Amontons' Second Law: The force of friction is independent of the apparent area of contact.
• Coulomb's Law of Friction: Kinetic friction is independent of the sliding velocity.

<tedious techno-nerd mode / off>

Good lubrication helps. Brass work hardens and steel polishes. Lots of clocks still running after centuries!

Best
Simon

 

[Steph Dale]

Simon,
It's been a long day and yes, you're correct. For some reason I was assuming constant pressure, not load.
It does deviate a little from classic theory once the effects of plastic and elastic deformation are taken into account, but the overall effect is negligible.
And, as you suggest, it'll likely work well for a long time anyway.
Steph

Blimey, that post took an age to type thanks to spellcheck. Mind you, it still might all be gobbledegook anyway...

 

[Dikitriki]

Hi,

Thank you folks. I shall go down the decent lubrication and easy life route. Given my usual 10 year running in period, I should know where I'm going before I paint it.

On to the outer chassis now. I'm going to let the pictures speak for themselves, but will make the following comments.
The footstep stays are designed in. Normally it's a battle to cut and form them to the right length. These just slot in and hold everything vertical.
The transverse bracket carrier on the inner chassis has to fit exactly inside the sideframes on the outer chassis. It does, and the fit is perfect.
I have had to fit a bit of shim to get exactly the right ride height, but that may be just accumulated tolerances in my build of the compensation.
It's really just a case of following the instructions carefully. It all fits and is a joy to build.











Again, not quite finished, but I'm going to move onto the body and the front bulkhead now.

Richard

 

[Cliff Williams]

Can I suggest you remove the front tender buffers and set them right back against the drawbar? You will need to do this - I have built a few of these now and all needed it doing to get it round corners.

 

[Dikitriki]

Thanks Cliff,

I wondered about that, but until I had engine and tender together, I wasn't able to work out if there was a problem.

Richard

 

[demu1037]

Thanks Cliff,

I wondered about that, but until I had engine and tender together, I wasn't able to work out if there was a problem.

Richard

what!!, you haven't 'sprung' them??