Author Topic: CONWAY 0-4-0 3 1/2" GAUGE LOCO  (Read 72331 times)

Offline g0rph

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #765 on: February 15, 2019, 11:59:32 AM »
Hi Rich,

>>>>>The springs I have used seem to be about right at the moment but as the weight increases they may have to be changed>>>>>

Can you tell me the details of your current springs, please?

My springs seem to work OK but they are rather too stiff, probably because they are too short.   The uncompressed length is only 10mm, fitted they are ~9mm,  and they are of 18SWG piano wire.   Four per axle like yours.

I'm not sure whether to lengthen them AND make them thinner, or just to lengthen them.    I've a mind to make some about 20mm uncompressed and ~15mm installed length, possibly reducing to 20SWG.   Longer spring pins will be fitted to suit.   

Details of what you are using would be useful to help me to decide!   if yours are currently 20SWG and on the weak side (for the finished loco), I'll stick with the 18SWG.

Thanks,   Richard.

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #766 on: February 15, 2019, 01:27:39 PM »
Hi Richard

Just stripped one of the springs off and the measurements are roughly



Which is about 20 gauge

Hope that helps

Cheers

Rich

Offline g0rph

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #767 on: February 15, 2019, 04:36:02 PM »
Thanks Rich,

Yes, that's a big help!    I 'll let you know how it goes.   It will be a while though before the loco is ready to run on the track again as I'm doing a major overhaul at present!

Dummy leaf springs are being made at ths moment as the chassis is a bit bare under the saddle tank without any!   The working coil springs can be attended to next!

If I can help at all, just ask!

Regards,   Richard

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #768 on: February 15, 2019, 08:53:26 PM »
Hi

Thanks Richard  :ThumbsUp:

The valve rod couplings were just touching part of the brake linkage, fortunately I managed to get in with a hand held tool to grind a small amount off. Anything to avoid taking the valve linkage apart :hellno:




Brazed the chimney into its base



Held it in the lathe to file it clean



Followed by a coat of etching primer



The exhaust flanges silver soldered to brass tubes



A trial fit



A length of 1/2" brass tube threaded each end



A good tip when holding thin walled tube is to push a drill of the appropriate size inside to prevent crushing





A trial fit of the blast nozzle




Cheers

Rich

Online Kim

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #769 on: February 16, 2019, 05:45:30 AM »
Very nice looking chimney there, Rich!
Kim

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #770 on: February 17, 2019, 10:40:41 AM »
Hi

Thanks Kim  :ThumbsUp:

The piece of brass tube I used for the exhaust blast nozzle is exactly .5" but is a loose fit in the blast nozzle. On closer inspection the threads in the blast nozzle are not very good, silver soldering may have damaged them slightly  :headscratch:





The blast nozzle was a right pain the *#@$ to make so I didn't fancy doing it again  :ShakeHead:

My solution was to turn up a length of brass .010" oversize ie .510" and screw cut the thread





I was still able to get it into a 1/2" collet to drill the hole







A much tighter fit. Hopefully I will only have to assemble this once so with a good application of thread sealant it will do the job

Cheers

Rich


Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #771 on: February 17, 2019, 10:49:24 AM »
Hi

I have made an adapter for the steam T taking it down from 5/16" to 1/4". There is plenty of room in there so I can now fit a commercial oil check valve



Cheers

Rich

Offline Steve17

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #772 on: February 17, 2019, 10:50:13 AM »
It's coming along really nicely Rich. Must admit I've made more oversize threads threads than I care to remember, it's always brass that does it for me. Now I just tell myself it's just constant pitch or bespoke with 50% done with standard tooling. :shrug:

Steve.

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #773 on: February 17, 2019, 11:07:00 AM »
Hi

Thanks Steve  :ThumbsUp:

With the steam pipe and blast pipe in place I made a cardboard template of the smoke box floor and transferred the hole positions to the brass floor. Drilled out with a step drill and a trial assembly









Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #774 on: February 17, 2019, 12:06:04 PM »
Hi

With the boiler in position



The chimney has been sprayed with matt stove paint

Cheers

Rich


Offline b.lindsey

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #775 on: February 17, 2019, 02:09:10 PM »
More great progress Rich, and nice recoveries from the little issues along the way as well.

Bill

Online sco

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #776 on: February 17, 2019, 05:32:05 PM »
Starting to look like a proper little locomotive!

Simon.
Ars longa, vita brevis.

Offline g0rph

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #777 on: February 17, 2019, 10:41:34 PM »
Another disadvantage of sidetanks....... is that you need a new outer dome ;)

Regards Richard.

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #778 on: February 18, 2019, 07:41:58 PM »
Hi

Thanks Bill and Simon  :ThumbsUp:

Richard, yes the dome will have to be stretched a little.

Lots of things to fettle and modify as we go along. Just noticed the reverse lever is too close to the side of the boiler so will have to be packed out a little more

Cheers

Rich

Offline g0rph

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #779 on: February 18, 2019, 11:29:19 PM »
Hi Rich,

Looking closely at your pics, I wonder if the blast nozzle is aluminium bronze?   That might explain the poor threads?

I always have problems tapping that material (and it needs modified flux to get a decent silver-solder joint too!).

It is just a thought though, you seem to have solved the problem OK!

Regards , Richard.