Author Topic: CONWAY 0-4-0 3 1/2" GAUGE LOCO  (Read 60279 times)

Offline scc

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #510 on: July 08, 2018, 08:15:54 PM »
I like it a lot :popcorn:

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #511 on: July 08, 2018, 09:16:30 PM »
Hi

Thanks Nick and SCC :ThumbsUp:

We also need a blast nozzle and blower  ::)



This took a bit of studying to figure out how it works and how to make it so I'll give a little more detail.

Starting with a bit of phospher bronze bar, face and machine a 1/8" deep pocket and part off and finish to 7/16" as per the plan



Looking at the part it just didn't look right  :thinking:. After some more studying of the plans it finally dawned on me that there is an error on the drawing. Good old Martin errors has struck again  :cussing: :Mad:

The dimension showing the total height of 11/16" is wrong. It should be 13/16".

Start again and make the part the correct size



Using the same bar make the cap







Silver solder the two parts together





This makes an internal circular chamber

To cut the internal taper and tapping size hole for the 1/2" x 32 tpi I made a cutter. Starting with some silver steel turn the taper, the tap size and the 3/16" spigot to 1/8" long



Transfer to the mill and machine away exactly half the diameter







Heat to cherry red and quench in clean water. I didn't bother to temper it.

The part is mounted in the lathe and drilled through 3/16" followed by the custom made cutter









The cutter is advanced slowly until the 3/16" spigot just protrudes and is flush with the face of the part

Followed by the 1/2" x 32 tap



Now comes the 4 little jets. And they are small. Too small for my eyes  :hellno:

I have one of these little CO baby lathes. Too be honest they are in my opinion not that good for general work but where they do score points is the 3800 rpm they are capable of. So I dragged it out and donned some magnifying glasses.

The jets are made from some 5/32" brass hex. Turn down and thread. I have used M3. Drill the larger hole. Cut off and make another 3.



Chuck a bit of scrap brass, face and drill and tap M3. Each jet can be screwed in and with a hand ground cutter turned to profile.





With the tiniest of drills, which I could barely see, drill the jets



The body must be drilled and tapped M3 at an angle of 2. I have a rotary table that tilts





Back in the mill to drill and tap 1/4" x 40 and silver solder in a bit of threaded brass that is centre drilled to form the cone







A few shots of the finished part







Cheers

Rich






« Last Edit: July 08, 2018, 10:26:07 PM by Firebird »

Offline Kim

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #512 on: July 09, 2018, 12:49:46 AM »
Wow!  That's a lot of little work there!
Kim

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #513 on: July 11, 2018, 10:03:52 PM »
Hi

Thanks Kim  :ThumbsUp:

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #514 on: July 15, 2018, 08:39:17 AM »
Hi

Next is the exhaust T and pipes

Starting with a block of bronze drill and tap 1/2" x 32







Mark the sides and set at an angle of 30





Drill with a 5/16" slot cutter









Drill and tap M3







Make the flanges





There are a couple of photos to follow when I get them uploaded. Use.com is off line at the moment

Cheers

Rich



Offline scc

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #515 on: July 15, 2018, 09:42:38 AM »
Nice work :cheers:    Terry

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #516 on: July 15, 2018, 04:55:49 PM »
Hi

Thanks Terry  :ThumbsUp:



A couple of lengths of 3/8" brass tube threaded 3/8" x 40. Slightly over long at the moment. When I get the cylinders mounted I will be able to get the correct length and silver solder them to the flanges



Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #517 on: July 21, 2018, 07:35:42 PM »
Hi

Some more steam fittings work and a question for you my learned friends  :thinking:

First of all the steam T. Made from a block of bronze





Followed by a pair of flanges to connect it to the valve chest covers. I'm waiting for some 5/16" brass tube to arrive



Heres the question. You will see on the drawing an oil check valve. I can see that it would be necessary if a mechanical lubricator were fitted but my intention is to fit a displacement lubricator. Am I right in assuming that I won't need the check valve :headscratch: :thinking: :noidea:

When I made the cylinders the lug for the exhaust steam outlet was omitted to save wasting a lot of material. 2 more blocks of bronze have been machined to make the outlet connections











Finally today I have made a start on the wet header

Turn to size, drill and tap 5/16" x 32, screw cut 1/2" x 32



Cheers

Rich

Left as one piece at the moment. I am going to drill and tap the 3 holes then seperate the 2 pieces





Offline Kim

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #518 on: July 22, 2018, 05:52:37 AM »
Hi Rich,
Some nice looking little brass parts you've made there!

Heres the question. You will see on the drawing an oil check valve. I can see that it would be necessary if a mechanical lubricator were fitted but my intention is to fit a displacement lubricator. Am I right in assuming that I won't need the check valve :headscratch: :thinking: :noidea:
Since no actual knowledgeable people have answered your question, here's my less than knowledgeable thoughts...

I think that the check valve is not only not needed, it would prevent the displacement lubricator from working if it were there.  A displacement lubricator works by having the steam come into the unit and condense, raising the level of the oil (since the oil is lighter than water) and then being pushed back out the same passageway the steam came in to drip into the steam line as it goes into the cylinders.

And a check valve would prevent movement in one direction or the other.  You need fluids moving both ways for the displacement lubricator to work.

If I'm wrong, I'm sure someone will correct me, but that's what I think based on my limited knowledge.

Kim

Offline Jasonb

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #519 on: July 22, 2018, 07:20:31 AM »
No need on a displacement lub, it is all under steam pressure.

A mech lub does not have  asealed top so steam from the valve chest would blow back up the pipe and cover you in oily steam. Infact a lot of mech lubricators are best with two NR valves, one in th eoutlet and another where the tube joins the valve chest

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #520 on: July 23, 2018, 07:47:08 PM »
Hi

Thanks Kim and Jason  :ThumbsUp: :ThumbsUp:

I figured that would be the case but wasn't 100% certain

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #521 on: July 27, 2018, 11:09:57 AM »
Hi

Question time again  :help:

I'm still making boiler fittings, I'll post the progress later. I am now onto the super heater. There is very little info in the article, little more than a drawing



This is the drawing that Julias did



You will see on the first drawing the length of 16 3/4". A tape measure held inside the firebox



Which clearly sticks out the front way too much



Holding the tape measure much shorter at the front, which is about where the end should be



Results in the end sticking right out into the firebox



This is all new to me  :headscratch: so I would just like to check that is correct, ie the super heater does stick out into the firebox and there is not another Martin Evans error on the plans

Cheers

Rich





Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #522 on: July 27, 2018, 11:11:35 AM »
Hi

Hmmmmmmmmmmmmm

It seems all my images from Use.com have disappeared.

I'll look into it

Sorry

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #523 on: July 27, 2018, 11:23:53 AM »
Hi

I think it might be something to do with Google chrome

Effective July 2018, Google's Chrome browser will mark non-HTTPS sites as 'not secure' - Search Engine Land
https://searchengineland.com/effective-july-2018-googles-chrome-browser-will-mark-non-https-sites-as-not-secure-291623

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #524 on: July 27, 2018, 11:37:47 PM »
Hi

All the images seem to be back again :headscratch:

So back to the super heater question :help:

Cheeers

Rich