Brian's 1" Minnie Traction Engine

I have a vague recollection of someone telling me about improving gas flow by placng the cylinder in a barrel of warm water.

Perhaps having the job of a gas BBQ might also help?

I use a Rothenberger torch with MAPP gas - you will never have a problem soldering / brazing again!

The heat output of these things is phenomenal, and while they're not cheap they make the job so much easier.

There are other makes available, usually described as a Turbo Torch, but the MAPP gas makes all the difference.

Hello all, thank you for your reply's.

Phil, interesting information about the gas bottles take off.

I have ordered a 43.5kw burner which will be connected to a 19Kg bottle of gas.

I have had a couple of quotations to have the boiler made, not cheap but knowing the amount of work that is involved i am not surprised.

I would really like to crack this so fingers crossed this will get me a little closer, and if nothing else i am getting quick at making flanged plates for the fire box..

Hello Brian,

That's quite a flame you will have there, based on what I remember of the Bullfinch torch I used.  It's going to consume about 3.5kg per hour.

Boiler making is I fear, a difficult and costly skill to acquire.

Phil

Edited By CotswoldsPhil on 05/01/2016 11:49:34

Hello Phil,

That’s what worries me, bottom line is that working with such equipment is dangerous and maybe I should be leaving this to the professionals!

I am going to have a go with this new torch, but not going to push it, if I am any doubt I will have to bite the bullet and invest.

Well it's beaten me....all I can do is console myself that silver soldering and boiler making is a skill that must be learnt over many years.

I have seen much improvement with my efforts, but they will never be at a level I would be happy with.

Is there anything I should be looking out for when getting a boiler commercially made ?

Hi Brian,

You are in exactly the same place as I was a good few years ago. I'm now pondering whether I should try and complete the Minnie boiler I started in the 70's.

With this in mind, some good advice has just appeared in another thread on silver soldering which may be of interest:

**LINK**

Regards

Phil

Edited By CotswoldsPhil on 13/01/2016 09:48:03

Thanks Phil, some good advice in there.

I have resigned myself to having one made, either GB boilers or Chedder valley.

Would have liked to go to western steam but my budget will not allow it.

Must say, all the worry about ending up with something i am not happy with is making think i should put the lot in a box and have a break for a while..

not to worry,

Brian

I read the story of someone who used warmer and then warmer water on a small cylinder until... it made their parents quite cross...

Neil

Hi Brian,

My engine, for what it's worth, took the best part of 40 years to complete (it still needs painting) between work and family commitments, slow-downs in the manner which you describe and other diversions. The last slow-down was caused by commercially available steering chains which kept on breaking, until I bit the bullet and came up with a method to manufacture and silver solder each link of the 18 inches of steering chain required for the engine.

Keep smiling it is just a hobby after all.

Regards

Phil

Edited By CotswoldsPhil on 13/01/2016 19:12:51

Thanks Phil, very true, need to keep this in mind...

Dropped all the parts from my boiler in on Saturday for someone else to solder it for me..very greatfull I am to them to.

Whilst it's away I am going to make a start on the horn plates and bearings, am I best to follow the book with regards to marking out the correct gear spacing, mark the position of the crank on both plates whilst they are attached to the boiler ( when it's back ) then set the spacing using the gear tool?

Thanks,

Edited By Brian Abbott on 17/01/2016 22:37:45

Edited By Brian Abbott on 17/01/2016 22:42:51

Hi Brian,

I apologise in advance if any of the following smacks of "teaching granny to suck eggs", it is just my experience of building a Minnie in my workshop .

Glad you have found a solution to your boiler construction issues, can't do much to a TE without the boiler.

The horn-plates should be bolted to the completed boiler before marking out the horn-plates. So this may give you an enforced break.

When I did the setting-out on the horn-plates, I did use the book's description (facing pg. 48) of a gear depthing tool, (not much else available to ME's at the time - DRO's 1970's?). The alternative being toolmakers buttons.

Once I had the crank-centre marked on both plates, I removed the horn-plates, aligned them and riveted them together using rivets in the waste area before marking out the rest. The pair of plates were then treated as a single item for marking-out / machining.

Make sure that the centre-points on the pins of your depthing tool are as accurate as possible (a job for the collet chuck?), and that the holes for the pins are perpendicular to the arms and that the pins are as short as practically possible, one pin projecting more that the other to compensate for the thickness of one arm. They do look a little long in the illustration.

You will need a spacer, to bring the pair of gears being meshed onto the same plane. It does test your marking out skills. I first drilled / reamed 1/4" holes to test the mesh of the gears on the actual horn-plates. You can then dial-in each 1/4" hole and finally drill / ream to size. Tool-makers buttons or DRO's make much of this procedure unnecessary of course.

Regards

Phil H

Edited By CotswoldsPhil on 18/01/2016 10:54:59

Hi Phil, thank you for the reply,

Must say I was going to try and stick to the book, but as I have used drilled and tapped bushes in the boiler I can spot through from the inside.

Plan was to clamp one plate to the boiler and mark from the inside of the smoke box, drill and re attached, then mark out as described using the gear tool.

Clamp both plates together as you describe and drill, once all assembled with bearings and shafts, bolt the drilled plate to the boiler, and clamp the opposite side ensuring all shafts spin as they should, then back spot again from the inside.

Hello all.

Need some advice on my Minnie please.

Is there any reason why I could not fix the crank and second shaft bearing by fixing them through the horn plates into the bearing, if I understand the book correctly it is suggested I tap the horn plates, don't really fancy that idea.

Thanks,

I tapped all my bearings so yes its OK to do it that way

Hello all.

Could i ask a question regarding the gear selector lever, should the 1/8" pins that run in the groove on the second gear shaft be on the center of the gear,

Thanks,

Brian

Eyeballing mine when in neutral I would say they are on ctr or just a fraction behind , the later seems to tie in with your red line

Edited By JasonB on 25/05/2016 18:02:05

Thanks Jason, will work on the center line.

Hello all.

About to start making the water gauge for my Minnie, not sure if to use brass or bronze.

Any advise ?

Bottom fitting comes into contact with boiler water so best in Bronze. You could leave the nuts that seal the tube in brass as they don't get wet and barss hex is easily available.