# Aster RMN Kit Build



## Charles (Jan 2, 2008)

Seems to be a well designed and straight forward kit. Read some necessary "adjustments" on the other forum along with an indepth discussion. Great support with Andrew (Aster UK):

Rebuilt Merchant Navy Kit Build

We will be doing a second kit and I will film the build process.


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## steamtom1 (Jan 2, 2008)

Charles,
Explain the term "Rebuilt" as it applies to this loco. 
I've done a little investigation, and it looks like they were all built in the '40s and rebuilt in the '50s. My question is "Why?".


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## Dave Meashey (Jan 2, 2008)

Tom;

This is from the Aster UK site. I think it will help answer your question.

The 30 Merchant Navy class locomotive suffered many operational problems mostly due to Bulleid’s untried and untested innovations. By 1955 British Railway’s engineering management decided that the only way to proceed was to completely re-engineer the Merchant Navy class. Consequently the air-smoothed casing, chain driven valve gear and other novel Bulleid features were removed and replaced by less troublesome conventional components. These modifications described as “rebuilding” completely changed the look and reliability of the whole class of locomotives. The first locomotive to receive the treatment was 35018 ‘British India Line’ in 1956. The final example was 35028 ‘Clan Line’ in 1960.

The Rebuilt Merchant Navy class were used on the heaviest express trains, for example the Bournemouth Belle and Atlantic Coast Express. Also the heavy Pullman service operating in association with international passenger services through Southampton’s Ocean Terminal.

Regards,
David Meashey


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## steamtom1 (Jan 2, 2008)

Thanks, Dave,
That answers my question.


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## David Leech (Dec 9, 2008)

Tom,
Just to add to David's answer - WHY did they bother to rebuild in 1956 - 1959 and then withdraw the locomotives in 1964 - 1967 - some only having been used for 5 years.
Well, British Railways just needed to keep steam going as long as they could until suitable diesel power was developed and together with the Standard classes of locomotives, the rebuilds were a cost effective way to go.
As a child, I was pulled by many, both in their original 'air smoothed' condition, as well as rebuilt, and are one of my favourite British locomotives.
All the best,
David Leech, Delta, Canada


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## cocobear (Apr 23, 2012)

Much more interesting to look at compared to their "Spam Can' origins.

dave


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## BigRedOne (Dec 13, 2012)

The link doesn't work for me, it takes me to Flikr's home page.


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## Charles (Jan 2, 2008)

*Section 4*

A bit of fiddling,filing, fussing and fitting but the components are well designed and functional so far in this step.

Step 4 RMN
Use the left and right arrows to move through to the various photos.

Just a few things to be put into place then air test for tuning.

If link does not work try:
https://www.flickr.com/photos/[email protected]/


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## Steve S. (Jan 2, 2008)

*Charles, I always look forward to your picture postings of assembly. I have never gotten the nerve up to try and build a kit myself, but from studying you and Ryan's pictures I have learned a lot about how these things work. Thanks.*


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## Charles (Jan 2, 2008)

*Step Four timing*

Finished the valve gear and running gear in step 4. Spent most of the time tuning and making sure that the valve gear had smooth motion requiring lots of disassembly: filing, adjusting, aligning, clearance along with setting the marks so that it will running well.

Step 4 timing 

Timing photos forth coming....


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## Charles (Jan 2, 2008)

*Steps 4-7 complete timing video*

Having complete the basic chassis and air tested through step7 onto the boiler and backhead:

Completed Steps 4-7

Air test chassis


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## Charles (Jan 2, 2008)

On to step 10-14 boiler fitting and details
On to step 15 Tender build

Current photos


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## dougiel (Jun 3, 2008)

Charles, you seem to be romping through the construction of this kit. Nice to see how others do it. As you are a skilled kit builder it is nice to know you had to carry out some of the rectification to parts that I did on mine. All told I have spent 7 months building mine and its still not quite complete. When parts did not line up well I tended to put them aside and go back later when I was in a better frame of mind. Very nice looking model now its nearly done though.

Hopefully it goes for a running in turn today if the wind here in the UK is not too bad.

DougieL


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## Charles (Jan 2, 2008)

*Step 18*

Going onto the home straight having completed the tender set up:

Tender Step 18

The one aspect that we thought would help prevent a rebuild of the kit was to put crush washers onto the inner cylinder high pressure banjo fitting:

Inner cylinder upgrade


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## dougiel (Jun 3, 2008)

*First Runs*

Well I got my wish to run the RMN a week last Saturday. Conditions were a bit (very at times) windy but the loco ran very well. It appears to be very smooth and controllable. I had two running in turns, one light engine and one with three coaches.

The only downside was it seems to not like curves. On one of 10 foot radii it would slow down quite a lot. It then came out of the curve onto the straight and accelerated. Even though it was going uphill at 1 in 130. And into the wind. This was both light engine and with three heavy brass coaches.

Just got to find a way to secure the cab windows now and a couple of handrails to fit.


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## StackTalk (May 16, 2014)

> . . . The one aspect that we thought would help prevent a rebuild of the kit was to put crush washers onto the inner cylinder high pressure banjo fitting:
> 
> Inner cylinder upgrade


Charles,

I find the above to be interesting. Did you fit the crush washers on dry or did you add sealant?

Why not use them on the outside and not just on the inner cylinder?

Seems that are readily available here:

http://www.mcmaster.com/#crush-washers/=wc051b

Have you used them successfully in the past or was this a new idea?

Cheers,

Joe


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## rbednarik (Jan 2, 2008)

Joe,

The copper crush washers haven't been fitted to the outer cylinders yet as the steam piping to them goes on once the boiler is on the frame with the smokebox saddle.

We have been doing this for years where space permits on banjo and boiler fittings, especially on hard to reach high pressure fittings as they provide a positive seal despite heat andout expansion. The washers can be applied dry, but for peace of mind a small thin film of high temperature thread sealer (permatex) is used either side of the banjo bolt. 

Much better than just some silicone on the banjo fitting and it avoids any potential blowout due to inadequte silicone on the banjo. Usually these blow out in the most inconvient of spots. 

These crush washers are not the same as mcmaster carr's offerings. They are 5mm id with a small od (~7mm) and a very thin thickness. These also allow indexing of a bolt or fitting by stacking and shimming. Useful where a lock nut cannot be applied.

Washers are from Regner and are available in the USA through The Train Dept. They come in 5mm and 6mm inside diameters


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## StackTalk (May 16, 2014)

Ryan,

Thank you for a very complete and very helpful reply.

I haven't experienced any blowouts as yet, but then my population is a little smaller than yours at just five Aster locos, plus one sitting in a box ready to be built when the mood strikes me. 

I Hadn't checked sizes when I posted above, but I thought the link to McMaster-Carr would either confirm that I was headed in the right direction, or else you or Charles would have redirected me.

I do buy from McMaster regularly for work and hobbyist projects.

Thanks again,

Joe


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## rbednarik (Jan 2, 2008)

Joe,

These are not easy to source in the US as most crush washers are for automotive use. I have had good success making them in house from bronze stock but for ease of use and time saving it is easier to buy them! 

The McMaster-Carr listed crush washers are too large and far too thick for this application. The smallest they come is 6mm ID with an 11mm OD. The sealing "shims" are the right thickness but still not the right ID and OD to work with these fittings. Although great for supplies and the like, unfortunately not everything in their industrial catalog scales for Gauge 1.

Most Aster fittings on steam circuits for multi-cylinder engines (with exception) are M5x0.5, so the 6mm ID washer will flop around and potentially make more leaks than it seals.

The Regner crush washers take up no more than "a few thou" once installed as they are paper thin when crushed.

The other positive with the copper crush is that they can easily be reused should you need to take the fittings off for maintenance, fettling or repositioning. This is not possible with just straight silicone sealer. 

However, the OEM method is OK, do not get me wrong, it is just having had a few where the silicone has blown out, the copper crush route eliminates that to a very low margin of error.


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## dougiel (Jun 3, 2008)

I also have not had any "blowouts" on banjo joints yet on my Aster's. I do have one broken banjo bolt though. King from 1999 ? which had stood all these years without a run. Its the top one on the water pump and will not go back in without removing the boiler.

Bummer !. All those other bolts to undo !. May try and get some of these washers here in the UK to try

DougieL


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## StackTalk (May 16, 2014)

Ryan,

Thanks again. I mentioned I had not checked size before making my post, but I did notice that the smallest size McMaster's stocked was M6 with a fairly large OD delta.

So, when in need, I will be sure to contact Jason and get some Regner crush washers from The Train Department. There are a few odds and ends I will add to make up a small order.

Dougie . . .

It seems like a real pain to take a 4 cylinder loco apart but I did have the pleasure of doing so twice with my Castle. 

The first time was because of a clearance issue I had not discovered on one of the 'tween frames eccentric straps where the halves bolt together - that only showed up in reverse and because, as a "new guy" to building an Aster, I had over-tightened the piston and valve rod glands, pinching the o-rings. I subsequently felt that I wanted to decrease the chassis rolling resistance and so off the boiler came. Both issues solved after disassembly and reassembly. It took a couple of hours to take it apart and may be 2 or 3 times as long to put it back together again.

It was fine for a time afterward.

The second time was a personal tragedy. 

Two of the very small screws, an M1.4-7. Dwg. 2, inserted into P/N 14 had come loose on both sides of the valve gear eccentric straps, essentially rendering the inside cylinders not only to become useless, but also an impediment to the outside cylinders! 















Aster provides holes in various places on the frame to allow one to get at various screws, but these little screws cannot be reached except after removing not only the boiler, but the two outside cylinders.

These screws were reinstalled using Loctite 263 and I make no apologies for use of such a strong thread-locker on such a delicate and impossible-to-reach assembly.

Besides, the smaller the fastener, the less effective the thread-locker is anyway. And if there is any lubricant left on the threads, this weakens the bond as well.

So far; so good.

I am hoping to live out the rest of my days without having the boiler and outer cylinders of the castle off again. 

Cheers,

Joe

PS: Back to things RMN!


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