The Post Man Cometh.

[Nick_GParticipant @nick_g]

.

This eve I finished the cross head and decided to call it a night. Busy Monday and tired so doing more would be asking for a cock up.

Nick

[NJHParticipant @njh]

Very wise Nick – I have a few bits in

y scrap bin where I should have left we'll alone until the next day.

Norman

[Nick_GParticipant @nick_g]

Posted by NJH on 02/02/2015 22:06:17:

Very wise Nick – I have a few bits in

y scrap bin where I should have left we'll alone until the next day.

Norman

I think most of us have found out the hard way on that one. I know I have.!

Nick

[Nick_GParticipant @nick_g]

.

Bit of advice please guys.

I need to make the conrod. Which on the James Coombes is a Y shaped affair. Like most engines of this type its a highly visual part of the engine. So in addition to it being the correct size and not distorted in any direction it has to look 'pretty'

I need to make this :-

Out of this :-

What's the best way to go about it do we think.?

Cheers, Nick

[JasonBModerator @jasonb]

I would get the holes in the ends of the two main rods early on while they are still square.

So square off the ends leaving as long as possible, centre drill one end. Then hold in teh mill vice, use an edge finder to locate the undrilled end the and zero your dro, find center across the bar and zero the other axis. Measure in half the radius which I can't quite see and drill & ream the 1/8" hole. Move down 6 9/16" then drill and ream that hole. Repeat for the other rod/

You can now hold in the 4-jaw by the little end with ctr support in teh other to turn the fish belly, then shape the ends which will remove the ctr hole.

Cross piece is basic turning, I would drill & ream a cross hole 3/16" dia and counter bore a little way 1/4", don't debur the 3/16" hole.

Big end is again turning in the 4-jaw, its not dimensioned but tahe the round part down to 1/4" to fit teh counter bore and then form a 3/16" stub on the end.

Test assemble to get the location of the big end hole, drill & ream then file or mill the rounded end.

Fit the big end to the cross piece with loctite, when dry add a pin with a bit of loctite. Then add the two long pieces again with loctite and pin when dry. don't debut the pin holes. All assembly on a flat surface. Once all the loctite has dried file off the ends of the pins and the projecting 3/16" spigot, you should hardly see the joints.

J

PS if you don't know how to do the fish belly ask.

[NJHParticipant @njh]

Nick

I've not built this myself but have been tempted from time to time! The best source of information * I've found on Stuart models are the books by Andrew Smith – in this case "Building the James Coombes Table Engine. I don't know if they are still available but it's worth an internet search or, indeed, do Stuart Turner sell them?

I'm assuming that it is the long tapered connecting rods that is your concern? A.S. centre drills the ends of each long square piece and then machines between centres. This allows work to be taken out and reversed to facilitate the production of the tapers – finishing, I guess, with a fine file to blend them together.

Norman

* PS. Alternatively, having seen Jason's authoritative advice since I posted, listen to him! 

N

 

Edited By NJH on 09/02/2015 19:26:24

[NJHParticipant @njh]

Nick

Yes – Stuart Models do sell the book. See their site – part No. :- 36-50-72466

N

[Nick_GParticipant @nick_g]

.

This weekend I have been making the parts that link the eccentric to the valves.

So basically the bits from the brass eccentric strap up to the valve cross head. Some parts want finishing / dressing and some threads shortening but basically this section is sorted. (hopefully)

Nick

[Harry WilkesParticipant @harrywilkes58467]

Nice work it looking good.

H

[ChrisHParticipant @chrish]

I like I like it, very nice, you're inspiring me!!

Chris

[Nick_GParticipant @nick_g]

.

Thanks for the nice remarks guys,

Chris. Normally the only thing I have ever inspired is women wanting to stick knives in me.

Nick

[Nick_GParticipant @nick_g]

.

I have started doing some painting.

I still have a few parts to make but these will not require paint. The reason I have started painting is I am using Humbrol enamels which I know have quite a long drying time comparison to acrylic and I figure I can make the remaining parts while each coat is drying.

Question.! ……… How long should I leave the Humbrol enamel between coats.? – I know that this is temperature related and there is a difference between dry and cured paint. But if someone can put me in the ball park please.

Cheers, Nick

[Nick_GParticipant @nick_g]

.

Can anyone answer the paint dry / cure question.?

Cheers, Nick

[pgk pgkParticipant @pgkpgk17461]

..from humbrol's website: (the last time I used their paint was 52 years ago)

Tip: Humbrol Products: Drying Times

Paints

• Enamel Gloss Paints: Surface dry 1 – 2 hours, Fully dry in 24 hours
• Enamel Matt & Satin Paints: Surface dry 20-40 minutes, Fully dry in 24 hours
• Enamel Metallics: Fully dry in approx 10 days
• Acrylic paints: Fully dry in 1-2 hours, please allow longer for Gloss and Metallic finishes
• Acrylic Sprays: 15-30 minutes

Sprays

• Fluorescent Sprays: 15-30 minutes
• Multi-Effect Sprays: 15-30 minutes
• Metal Cote Sprays: 30-60 minutes
• Glass Etch: 15-30 minutes
• Crystal Clear: 15-30 minutes

Weathering

• Weathering Powders: Dependent on the application
• Enamel Wash 10-20 minutes

[JasonBModerator @jasonb]

Are you airbrushing, brush painting or using spary cans as the film thickness and amount of thinner in the three options will all affect drying times.

Also whats the primer a sthat can affect drying too.

[Neil WyattModerator @neilwyatt]

Fresh Humbrol dries OK, old stuff isn't so good, but adding the proper thinners (not white spirit) can improve drying times. Some ancient Brunswick green freshed up with a little thinners dried OK in a day and a half on my Parvalux. the brand new blue for the Adept dried overnight, but it was in a very warm place over a heater (about 30 degrees). both brush applied.

I would allow 24 hours between coats for fresh paint at room temperature and a few days for it to fully set.

Matt dries much quicker.

neil

[Nick_GParticipant @nick_g]

Posted by JasonB on 20/02/2015 17:24:13:

Are you airbrushing, brush painting or using spary cans as the film thickness and amount of thinner in the three options will all affect drying times.

Also whats the primer a sthat can affect drying too.

Thanks for the information chaps.

Jason. I am using an airbrush with the paint thinned with enamel thinners. Using No.1 matt as a primer so far.

I started at a ratio of 2 paint to 1 thinners, however I seem to get a better result when mixed 1:1 through the airbrush. I presume this may also change when I use a different paint for the top coats.?

I am as you may guess new to airbrushing so I still have a lot to learn re paint types, thinning, air pressure and spraying technique for best results. – Perhaps I should remind myself I am painting a model steam engine here and not requiring the finish of a new Bentley lol

I also have a supply of a 5 ltr can of cellulose thinners. But I am presuming that changing to this once a paint job has started may lead to issues with the coats already laid down.??? So I am just using that for airbrush cleaning.

Thanks, Nick

[NJHParticipant @njh]

Nick

My experience is don't apply cellulose over enamel – unless you are seeking a "crackle" finish!

Norman

Edited By NJH on 21/02/2015 10:25:14

[JasonBModerator @jasonb]

Well I've just come in from spraying my Cameron pump, put 3 coats of Precision Paints enamel on it in about 1hrs.

I was thinning about 2paint : 1 thinners, by the time all the parts had been given a first coat I could go back and apply the next. Will leave them now for a couple of hours to see what if any need a slight rub down. Don't try and cover it all in one go, several light coats will be better and then you don't risk the paint sagging.

Don't use the cellulose now it will lift underlaying coats. Use it for cleaning, blow some through teh airbrush and don't have a Fag at the same time

[Nick_GParticipant @nick_g]

Posted by JasonB on 21/02/2015 10:46:34:

and don't have a Fag at the same time

Ooooops. ……….. Too late.!!

Nick

[Nick_GParticipant @nick_g]

.

Painting progressing :-

Humbrol 'Crimson' No.20

Nick

[Nick_GParticipant @nick_g]

.

Its been a couple of weeks since I last posted on my first build. So here is a bit of an update.

There is a short video here :- **LINK** of me turning it over by hand.

I only have the con rod left to make. But I spent a bit of time getting the correct fittings of the parts and some polishing work. (I can see from the photos even from an iPhone that more needs to be done in that area.)

No more excuses the con rod is next. But I knew that if I made the last bit before polishing I would not have taken the thing to bits again I would not have been able to resist the temptation just to run it.!

Nick

[JasonBModerator @jasonb]

Almost there Nick and looking good. No reason to put off that conrod now.

I saw this yesterday and thought it might be about the right size given what you are thinking of making next

[Nick_GParticipant @nick_g]

fPosted by JasonB on 10/03/2015 07:29:38:

Almost there Nick and looking good. No reason to put off that conrod now.

I saw this yesterday and thought it might be about the right size given what you are thinking of making next

.

Fantastic. But unfortunately I dont have £2K to play with ATM.

Nick

[KWILParticipant @kwil]

Hang on, you are talking about Station Road Steam, what did you expect?

[Author]

Posts