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       The Unofficial Mamod and Other Steam Forum Forum Index -> Locomotives
shiphayhill

Traction engine to locomotive

As a newbie I hope I'm putting this in the right section!

Anyway, here is my conversion of a very old battered Mamod traction engine to an overtype loco.  It has a ceramic gas burner; taking two screws out of the rear buffer beam allows the open cab to be taken off, complete with the gas tank and burner.

Results are varied, one day it goes well, another day it will appear short of steam.  I suspect that putting a couple of water tube loops under the boiler would pep it up a bit - I think that doing this would convert it to a Smithies boiler?

Since taking this shot the boiler has been lagged, and a smoke box door and couplings fitted.

[img]
[/img]
steamyjim

That is truly brilliant!

Any chance of some more pictures of the chassis and drive mechanism?
Les

That is a very clever conversion indeed, well done.

Also welcome to the forum.  
johnreid

Very Clever, I would love to see it running.
MooseMan

Oh wow, that's great!!! More and detailed pictures please!
pauly

That looks fantastic!
kevininasia

Love it! I have a soft spot for faux rivets and chains, and that has both. Would like to see a video .
Steve_S

That's great!
shiphayhill

Traction engine to locomotive

Hello and thank you for your welcome and nice comments.  Here are two more pictures, and I'll post a few more when I have them.

I began by stripping down the traction engine and I was surprised to find that the front inch or so of the boiler is dummy.  So I cut that off to keep down the overall length of the loco.  I cut out paper outlines of the big parts and pushed them around over a line drawn of a sheet of paper.  The line representing the top of the chassis.  I had some loco wheels from Roundhouse and I put them down on the paper as well, to work out where the axles and lower edge of the chassis would come.  Then I made the chassis to suit.  Later, I found it was a bit short at the rear, so you can see I have bolted on some extensions - maybe a little too long now!

As for the firebox, I used a piercing saw to cut off the lower parts of the end plates, just above the level of the ribs pressed into the wrapper by the holes for the traction engine axles.  I started cutting off the ends of the wrapper as well, but it didn't look right, so I flatted the wrapper and used it as a template for a new, shorter wrapper.

The frames are 43mm apart, to fit the scuttle of the Mamod gas burner assembly and this leaves just enough room for the wheels to be set to 32mm gauge.  In the end I cut off most of the scuttle anyway and fitted a more loco-like open cab.

The drive is by Meccano chains, first on the left from the crankshaft to the layshaft under the front of the boiler.  This is the main reduction stage.  The next chain is from the right-hand end of the layshaft to the front axle, with more reduction.  Finally the axles are coupled with another chain on the left-hand side.

[img]

[/img]
Keith S

I like that. It looks great.
steamyjim

Abslutely brilliant! I want to make a 45mm one now
Kevin Klein

That is the kind of thing I would like to do, except to make a traction engine. I'm afraid it might make my head hurt trying to figure out the engineering aspects of the layout.  

Good job.
johnreid

Mamods are so much easier along those lines Kevin, but would not look so real in your photos. I do hope there is video camera access for this one as still would love to see it in action
Keith S

Kevin Klein wrote:
That is the kind of thing I would like to do, except to make a traction engine. I'm afraid it might make my head hurt trying to figure out the engineering aspects of the layout.  

Good job.


I'm currently thinking of making a traction engine, using parts from various toy manufacturers and homemade parts and aftermarket suppliers. Let's collaborate. I have some ideas.
newsteamer123

that looks beast! does it run as wellas it did when it was a traction
shiphayhill

Traction engine to locomotive

Hi again,

Ahem, actually the rivets are real, doing their job, not faux

I'm not into video but I do have a digital camera that can take short video, I'll try it out next time I get the loco to work properly. But if it still is tempermental it wil be stripped down again and a couple of water tubes fitted into the flame space.  That should give it some get up and go!!

And I will be hoping I don't ruin the boiler and have to buy a new one.  Though I suppose it might be a good idea to make a silver soldered copper one.
ministeamer

Oh my god!! It's like..... Tank-train!!  
Have you seen Roly's TE Aveling and Porter?
whistleman

that's brilliant!  
shiphayhill

Traction engine to locomotive

Hi again,

I now have a short video of my loco in action but I'm afraid you will have to wait to see it.  I have lost the ability to insert pictures and things into these mailings, so no more pictures, still or video, until I can work out what's wrong.
shiphayhill

Traction engine to locomotive

Hi - yet again.

I have managed to put my video clip on Youtube - my first venture into uploading.

I can view it in my Youtube account but don't seem able to find it elsewhere, maybe searches don't bring up my own entries?

So I will be interested to hear if any of you are successful in finding it. Tags you can try are model and steam and the clip title is Huffalot.
Happy searching!
Roly Williams

Here it is:

Les

That goes really well.  
bessytractor

thats brilliant and yes your right, pot boiler with water legs in the firebox = smithies boiler = HARDCORE  
johnreid

Oh my, I do like that one for sure, thanks for going to the trouble of doing the video.
Keith S

I like you railway too. I intend to have a garden railway like that someday. The locomotive actually looks kind of real, although a real what I'm not sure. I like it.
Kevin Klein

That is most inspiring, if only I had room for an outdoor layout.
Sandman

That really runs well.

Inspirational.
Annie

Oh that is amazing!  I actually have a TE-1 boiler being posted out to me at the moment and I've got other steam bits I've been collecting in order to build a loco.  Your loco is wonderfully inspiring and I hope you won't mind if I borrow a little from some points of your design.
GUTMACH

Terrific little project you have there, really like the way it runs. Well done.

On top of alot of other projects   , I would be inclined to do a similar locomotive ! There would be a few minor changes, though, a Mamod-like cab, larger smokestack, and Mamod siderods instead of chains.

Thank you for the postings.

Wayde
Roly Williams

Annie wrote:
Oh that is amazing!  I actually have a TE-1 boiler being posted out to me at the moment and I've got other steam bits I've been collecting in order to build a loco.  Your loco is wonderfully inspiring and I hope you won't mind if I borrow a little from some points of your design.

If you're looking for inspiration for a TE based loco, you can take a look at my Aveling & Porter lookalike:

http://rolywilliams.com/AandP_lookalike.html

Wolcome to the forum, by the way.
shiphayhill

Traction engine to locomotive

Roly, Thanks for putting the YouTube link on the site for me,  much appreciated.

Wayde, I'm attaching (I hope) a picture of the starboard side which shows one reason for using a chain instead of side rods, the intermediate chain sprocket on the front axle.  It would not be impossible to use rods, but the chain is prototypical of some UK small industrial locos.

Everyone, no, I don't mind if my ideas are used by others; I find inspriation in others work - I am interested in Bert Coule's double Fairlie as I often wondered about the boiler problem.  His solution gives much more room for the flexible steam pipes.

Bother it! Sorry, no picture attached!  I'm not getting the little box that let's me find and attach pictures.  I did not have a problem when I started this thread.[/quote]
Titan

Re: Traction engine to locomotive

shiphayhill wrote:
I find inspriation in others work - I am interested in Bert Coule's double Fairlie as I often wondered about the boiler problem.  His solution gives much more room for the flexible steam pipes.



You might like to read this then!

http://modelsteam.myfreeforum.org/ftopic14110-0.php
shiphayhill

Traction engine to locomotive

I think I've cracked it.  Wayde, it you see this picture you can see that the drive sprocket on the axle gets in the way of siderods, unless you ut them outside the sprocket.  I think that might look odd.

shiphayhill

Traction engine to locomotive

Another short video clip showing the right-hand side.
[/img]
johnreid

I do like that one a lot, real nice garden railway too.
superbiker_uk

I love this model! Please can you provide part number or sizes for the meccano gears used as well as the source for the ladder chain?

Great pics and video - excellent stuff!
shiphayhill

Traction engine to locomotive

Superbiker - the ladder chain and sprockets are all Mecanno, either from my childhood or from eBay.

The one on the crankshaft is 3/4", driving a 2" on the intermediate shaft.  On the other end of that shaft is another 3/4" sprocket driving a 1" one on the front axle.  The axles are  linked using two 3/4" sprockets.  Total 4 @ 3/4" and one each of 1" and 2".

The chains need to be very slack because they seem to stretch very quickly if they are at all tight.

There is very little spare power and I think a bit more reduction might help, maybe a 3" instead of 2" on the intermediate shaft.

I could not use a 1.5" instead of 1" on the axle because it would foul the track at points.

By the way, my rail wheels are standard Roundhouse loco wheels.  They used to be on my Roundhouse loco but became spare when I fitted insulated wheels to cure a radio control interference problem.
Graham-Jilly

vould love to see a longer video
superbiker_uk

Thank you John! That is great info and I really do like your steam loco creation. Brilliant stuff.
shiphayhill

Traction engine to locomotive



Well, It goes but lacks power and is a bit quick.  So I'd like to increase the reduction gearing.  The easy way is to fit a bigger sprocket on the layshaft.  Ideally I'd like a 2,5 inch one, but I don't think Meccano made this size.  I've put on a 3 inch one, as shown in this picture, but I think it looks awful.  What do you think?

The other option would be to fit a second layshaft with a pait of Meccano gears.  More work, though.
ministeamer

Re: Traction engine to locomotive

shiphayhill wrote:


Well, It goes but lacks power and is a bit quick.  So I'd like to increase the reduction gearing.  The easy way is to fit a bigger sprocket on the layshaft.  Ideally I'd like a 2,5 inch one, but I don't think Meccano made this size.  I've put on a 3 inch one, as shown in this picture, but I think it looks awful.  What do you think?

The other option would be to fit a second layshaft with a pait of Meccano gears.  More work, though.
I totally aggree, it looks, well.... not so good. but the rest of it looks brilliant! I wish I had the skill to do that , not to mention the awesome railway!
Les

It looks far too big and it distracts you from the loco itself.
made-in-england

I dont think it looks all that bad...

ive started me own and shall experiment with that..

is there any gears here that are of use? This is the pack I have bought...

http://www.hobby.uk.com/products/...ss-hub-sprocket-starter-pack.html
shiphayhill

Traction engine to locomotive

Two to one against the big sprocket so far.

I forgot to reply to another guy who commented the chimney is rather short, and I totally agree.  I think I should have left it about 10mm taller.

Made-in-England:  Ummmm... I would be wary of plastic bits on a steam loco.  I suppose OK provided you keep them well clear of the really hot bits.  On my loco the burner sits between the rear wheels, a few mm above the axle and those wheels get really hot.  The heat is conducted to the sprocket on that axle, your gears have a brass hub which might get too hot for the plastic.

On the whole I think I'd go for Meccano bits.  You can find them on eBay and, as they are quite plentiful, are not over pricey.[/quote]
made-in-england

The Gears and Chain are brass they are jusy listed on the website with Plastic gear wheels...
johnreid

I like the look of the chain and gears, the big gear just looks out of place.
Minor1PJG

I've just seen this and it looks great and runs very nicely.  

Could you slow it down just with a heavier load? ?
Annie

Roly Williams wrote:
Annie wrote:
Oh that is amazing!  I actually have a TE-1 boiler being posted out to me at the moment and I've got other steam bits I've been collecting in order to build a loco.  Your loco is wonderfully inspiring and I hope you won't mind if I borrow a little from some points of your design.

If you're looking for inspiration for a TE based loco, you can take a look at my Aveling & Porter lookalike:

http://rolywilliams.com/AandP_lookalike.html

Welcome to the forum, by the way.


Your Aveling & Porter lookalike is amazing, thanks for posting the link.  
shiphayhill

Traction engine to locomotive



Here are pictures of what I hoped was the final version of the loco.  With a mix of Meccano gears and Meccano chain and sprockets, giving an overall redcution of 6:1.  This shoule both slow it down and give it more pull.

But disaster when I fired it up - the boiler leaked.  I'm puzzled as it was OK last week and didn't boil dry.  So the question is, do I use a new Mamod boiler or build a silver-soldered copper one?  So mthere will be no more news on this loco for a while.
alan2525

CJW steam can supply a silver soldered copper replacement boiler for the Mamod TE, if you didn't fancy making one yourself.
Dr. Rog

Great loco

Are you sure you need a new boiler? Where is the leak?
johnreid

When posting pictures pleas place a carriage return between them, that way the pictures and text in the thread can be read. Does it leak where there are rivets, or at the seams?
Les

I would double checked to where it laks first before buying/making a new boiler.
shiphayhill

Traction engine to locomotive

John, Alan and all,

Thanks for the advice and tips.  Especially about carriage return between pictures.

The leak is above the water line and I think I know where it is
but cannot be exactly sure without yet another stripdown.

In general, when it was not leaking, my boiler did seem a
little short of steam, even with the gas heating.  My son-in-law
is visiting at the moment and has brought his meths fired
traction engine with him.  This also has trouble raising enough
steam, it starts moving but uses the steam faster than it is
generated so quickly comes to a halt. We tried fitting my gas burner
but there was no significant improvement. I wonder if steam
shortage is a problem with Mamod traction engines generally?
ministeamer

no, it's not. My mamod TE runs like a maniac when I want it to.
Good luck with fixing it
Dr. Rog

Re: Traction engine to locomotive

shiphayhill wrote:
John, Alan and all,

Thanks for ..
My son-in-lawis visiting at the moment and has brought his meths fired
traction engine with him.  This also has trouble raising enough
steam, it starts moving but uses the steam faster than it is
generated so quickly comes to a halt. We tried fitting my gas burner
but there was no significant improvement. I wonder if steam
shortage is a problem with Mamod traction engines generally?


This sounds like there is a problem. Mamod meths fired engines raise plenty of steam, the question is where does it go?

Is the safety valve leaking? Does it blow off, yet the engine seem to run out of steam quickly?

It should run continuously on a flat surface until the fuel is used.
pauly

is the savety valve blowing off to early?
shiphayhill

Traction engine to locomotive

Safety valve leaking?  Ha ha:-) I have never yet seen mine even show a sign of steam from it!
Anyway, now the boiler has sprung a leak there is no way it can get any real pressure.
I'm going to strip it down again and locate the leak but, if the boiler seems too decrepit
I'll probably get a new boiler, they don't seem over costly.  And I'd like to use as much Mamod as I can.

As for my son-in-law's machine, no, the safety valve didn't seem to be leaking and it certainly
never raised enough pressure to lift.

Both machines have been much used in hard water areas and we are wondering if limescale is
insulating the water from the heat.
Roly Williams

Re: Traction engine to locomotive

shiphayhill wrote:
...
Both machines have been much used in hard water areas and we are wondering if limescale is
insulating the water from the heat.


That's quite possible. Fill the boiler with vinegar and leave for an hour or two. Make sure you rinse thoroughly afterwards. Also, thick soot on the bottom can have the same effect.
Dr. Rog

vinegar

A good flush out can do no harm.

Someone suggested diluting the vinegar to me once, I cannot remember where I picked that up. I have tried 50% vinegar 50% de-ionised water before with great success.
Titan

Re: Traction engine to locomotive

shiphayhill wrote:
Safety valve leaking?  Ha ha:-) I have never yet seen mine even show a sign of steam from it!
Anyway, now the boiler has sprung a leak there is no way it can get any real pressure.
I'm going to strip it down again and locate the leak but, if the boiler seems too decrepit
I'll probably get a new boiler, they don't seem over costly.  And I'd like to use as much Mamod as I can.

As for my son-in-law's machine, no, the safety valve didn't seem to be leaking and it certainly
never raised enough pressure to lift.

Both machines have been much used in hard water areas and we are wondering if limescale is
insulating the water from the heat.


Is anyone else slightly concerned by this? A safety valve that does not lift, and for some reason the boiler has sprung a leak - related perhaps?
Maybe the safety valve does not lift due to being scaled up from the hard water? It might be an idea to check it is not stuck...
tmuir

Re: Traction engine to locomotive

Titan wrote:
Maybe the safety valve does not lift due to being scaled up from the hard water? It might be an idea to check it is not stuck...


I agree this should actually be done before every run of any engine.
Although I must admit sometimes I forget to do it every time I do check that the safety valve lifts by hand most of the time before running an engine, especially one I haven't run for a while.
I've purchased plenty of secondhand engines where the safety valve was scaled up so much it wouldn't open but its usualy only taks a few minutes to fix it properly.
shiphayhill

Traction engine to locomotive

Nope, definitely the safety valves are not stuck.  And I emphasise that both boilers are short of steam.  Evidenced by the way my son-in-law's gets up enough pressure to move but quickly slows down and comes to a halt.  My own boiler sometimes seems to get enough steam but not always.

Mine is now in pieces again and the leak was around a copper blind rivet.  I have made two blind bushes threaded 6BA, flanges as thin as I judged reasonable, to replace the rivets, but have still to fit them.  Then I'll try the vinegar, rinse well, reassemble and try again.  I've also lapped the faces of the cylinder and frame to try to reduce steam loss there, but won't know if this is successful until I get it all back together.

It is a pity that both of a couple of silver soldered copper boilers I made some time ago are too short and too big in diameter ;-(  They are earmarked for a pair of single cylinder oscillating stationary engines, to the "Elizabeth" design of the late Tubal Cain.  Hopefully my grandchildren will make the actual engines when they are a little older.
John R

Leaks

If you cannot find the exact place of leaking, put a little Food Colour
in the Boiler Water and pump her up to 20 to 50 PSI, I`m certain
you will find the leak then!.
Works for me,
John.
shiphayhill

Hello, guys, time to give a progress report.

The boiler has been descaled using vinegar, quite a lot of sludge came out. The whistle bush has been blanked off and all leaks stopped.  Two water tubes have been fitted in the firebox.  The reverser has been converted to control from the footplate. This picture shows this.  I got fed up with drilling out pop rivets, so I have converted to bolt assembly, ising bolts into little bushes.

The queer thing on the water level plug is an extension to make it easier to fit when the footplate 'walls' are in place.



The three holes along the lower edge of the firebox sides take 8BA bolts which screw into the brass angles that form the 'floor' of the firebox sides.  This is the only fixing for the boiler assembly, the smoke box justs rests on the frame stretcher, which allows for expansion of the boiler.



The frames have been fitted with brackets for the two shafts of the reduction gearing.



So it now due for reassembling and testing.  More in a day or so.

Thanks for reading this, JohnK
Dr. Rog

So the whistle was leaking?

(its all looking very promising   )
Sandman

Looking forward to the next episode.
shiphayhill

Traction engine to locomotive

Yes, the whistle was leaking somewhat.  A very high pitched scream.  I didn't want the whistle anyway, so I took it out, cut off the whistle itself level with the bottom of the 'mouth' to leave a stub, soldered on a cap and screwed it back in.  This stub sticking up will be used to locate  a brass dummy steam dome

JohnK
Shiphay Hill Railway
bessytractor

you could put a water top up valve where the whistle was.
shiphayhill

Traction engine to locomotive

Hello guys,

Herewith (if I have done it correctly) a short video of Huffalot on the go.  The large Meccano sprocket wheel is actually turning the opposite way to how it looks, a bit like the old movies that showed cars.

Really it is finished now except for the bling, like handrails and so on.  Though at the back of my mind I'm still toying with the idea of a copper silver-soldered boiler.  And if I could put the cylinder in the lathe and open it up from 9mm to 10mm diameter, according to my maths that would give an increase in piston area and, therefore, possible torque, of 23%.  Which might cure the problem the thing has with rice pudding skins.

JohnK
Shiphay Hill Railway

superbiker_uk

Fantastic! This has inspired me to have a go at building one! I am just collecting up the bits i need for the build. Thanks for posting this great loco on the forum.

Regards, Peter
newsteamer123

very nice
L.North

OMG. That little engine can really move. Now you got me wanting to make one.
shiphayhill

Traction engine to locomotive

Just a quick update on progress - I am still trying to cure the shortage of steam.

Having now got a LOT of experience in stripping down and reassembling I have simplified and got it down to three modules.  The chassis, the boiler and the burner.

The boiler unit includes the boiler, the smoke box, the fire box and the engine.  It is fixed to the chassis with 6 8BA bolts.

The burner includes the burner, gas tank and cab.  It is fixed with just 2 8BA nuts and bolts.

Either unit can be removed from the chassis without disturbing the other.

The burner is the Mamod one for the traction engine, bought off eBay.  It seems quite small and I have got another burner from Forest Classics, which is almost the full length of the fire box, hopefully this will solve the steam shortage, when I have worked out how best to fit it.

I have taken pictures of the three modules for you but a little while ago I wrote all this, started adding the pictures and lost the article and had to start again.  So I am sending this without the pictures and will try to send them with very short mailings.

JohnK, Shiphay Hill Railway
shiphayhill

Traction engine to locomotive

Here (I hope) are the pictures of the modules:

First the burner.  Fairly simple.



Next, the chassis.  Note the bits spliced on the rear end, my frames turned out to be too short and I had to lengthen them.





Unfortunarely I dropped the next module just before I took the pictures.  The only damage is that the bolt holding the regulator to the bracket on the back of the firebox sheared off.  Pity, it is one I made specially, so it will be back to the lathe for me!

The smoke box just rests on the frame stretcher, though I have drilled the stretcher for a bolt.





I'll keep you posted on fitting the larger burner.

JohnK
made-in-england

I seem to be having a similar problem with mine, lack of steam,

does yours steam well on the bench? Mine does but soon as i take it out on the railway it dosnt like it at all!
shiphayhill

Traction engine to locomotive

made-in-england wrote:
I seem to be having a similar problem with mine, lack of steam,

does yours steam well on the bench? Mine does but soon as i take it out on the railway it dosnt like it at all!


Yes, that's it!

To be really exact, while mine runs quite fast on the bench, it does not get up to the astronomical rpm that one might expect running light.  To me it seems that it is just not boiling the water fast enough to generate enough pressure to run really fast on blocks or to cope with the extra load of actually moving along.

JohnK
ministeamer

Are your engines gas fired?
If not, it may be the wind?...
made-in-england

Mine is meths fired and I belive t'other one is gas.

We did put the bad run last time down to wind. Also next time I shall fill it up with hot water so the meths dosnt have to do as much.

On my loco there is not enough room to fit gas fireing unless i do some serious tweaking
shiphayhill

Traction engine to locomotive

Yes, my loco is gas fired.  I have now fitted the burner from Forest Classics, and what a difference!  The ceramic glows red hot and there is a good orange glow over it.  The first burner I had on the conversion looks much the same as the new one, but smaller.  However it does not glow and seems less effective.  Maybe the air:gas ratio was wrong.

Anyway, picture attached, exposure reduced to try to show the glow.  Tomorrow I'll refit the other bits and try it out properly.

Incidentally, the new burner has had to fixed to the chassis rather than the cab, so it not quite so quick to strip down, but the boiler module is not affected.

Dr. Rog

How was she?
Pendo Pilot

It's threads like these that have kept me glued to this site the last two days. Fantastic work, I do hope theres an update soon.
shiphayhill

Traction engine to locomotive

Sorry, guys.  This is dormant for a little while because my health is giving me trouble right now.  The cold weather does not agree with my athsmatic chest and I'm very wheezy.

Hopefully I'll be able to do some more in the workshop soon.

I have cut the planks for some new boiler lagging and still have to varnish and fix them and do a little tidying up.

Best wishes and a Happy New Year,
Dr. Rog

I have every simpathy. I have been unwell and its made this season one of the least "festive" ever for me.
PCLR

sorry to hear that guys hope both of you get better and get back to what you to best

           Michael
shiphayhill

Traction engine to locomotive

Hi all,
I am more or less back in working order now.  Now all I need is a bit of dry weather so that the garden is no longer a swamp and I can have a run.

Anyway, I have the boiler lagging finished and a thick disc of expanded polystyrene in the smake box to insulate the front plate of the boiler.  Piccies soon.

Meanwhile, has anyone actually got round to trying to make a similar conversion?  Would anyone like me to post approximate dimensions of my conversion?  Let me know...
Dr. Rog

Glad to hear it.

Weather's bad here too. We have almost run out of clothes as we can't get anything dried.
John Richards

Re: Traction engine to locomotive

shiphayhill wrote:
Hi all,
I am more or less back in working order now.  Now all I need is a bit of dry weather so that the garden is no longer a swamp and I can have a run.

Anyway, I have the boiler lagging finished and a thick disc of expanded polystyrene in the smake box to insulate the front plate of the boiler.  Piccies soon.

Meanwhile, has anyone actually got round to trying to make a similar conversion?  Would anyone like me to post approximate dimensions of my conversion?  Let me know...


If you dont mind I would like to know how many Teeth your`ve
got on the Meccano Chain Wheels so I can check against mine!.

Thanks for the oppotunity,

John.
shiphayhill

Traction engine to locomotive

Hi all,

Sorry for the delay in replying to the query on gear sizes, blame it on the grandchildren visiting for half-term

Forgive me if I don't count up the gear teeth, I will give you the Meccano part numbers and descriptions.

The parts are:

1.5" sprocket wheels, part 95a  1 off
0.75" ditto, part 96a                   5 off
1.5" gear wheels, part 27a        1 off
0.5" pinions, part 26                  1 off
Chain, part 94                            as required, about 36" should be adequate

Axles are standard Meccano, cut to length as required.

Note that one of the small sprocket wheels has to be bored out to fit the Mamod crank axle.  I did this on my little lathe, probably a drill press would be sufficiently accurate, we are talking Meccano, not watch making!  If it worries you I could do the job for you, for the cost of the return postage.

Hopefully these pictures will make my layout of the parts clear.  The drive is a small sprocket on the crank axle, driving the large sprocket on the first shaft.  This gives a reduction of 2:1,  On the other end of the first shaft the pinion drives the gear on the second shaft.  This gives a reduction of 3:1, so the overall reduction is 2 x 3 = 6:1.

The drive from second shaft to the front axle and the drive between the front and rear axle all use the small sprockets.

Pictures are below, hope that will all have been interesting.

Best wishes.



steamyjim

If it is still in bits, would you be able to measure up your frames please? With the dimensions and spacings of holes?
shiphayhill

Traction engine to locomotive

Jim - and any others who would like more info,

Well, my loco was designed “on the hoof”, with no drawings.  NOTE that my loco is to 32mm gauge.  If you are thinking of  45 mm things will not be so easy.

The chassis frames are of 30 x 1.5 mm steel. Here are some dimensions, taken with a school ruler!  All distances given are taken from the front end of the frames.

Length of frames 240 mm
Front axle 70 mm
Rear axle 135 mm

In the pictures you may be able to see that I have lengthened the frames with extensions at the rear.  The length above is the final length and you won’t need to extend them.

The two intermediate shafts are supported in steel  flat plates approximately 6 mm (to centre of shafts) above the top edge of the frames.  The shafts are standard Meccano and the holes have to be 1” centres if using Meccano gears.  The front shaft is about 38 mm back from the front of the frames.  The important thing here is that the chain on the left of the loco, from the front shaft to the front axle, must not foul the hub of the Meccano sprocket on the rear shaft.

12 mm back from the front of the frame I fitted a 5/8” x ¼” stretcher, flush with the top of the frame.  The “perch” under the smoke box of the traction engine rests on this stretcher.  If you have not placed the shafts too high they will sit very nicely in the space under the boiler. In the pictures you can see that I have cut away the top of the frames in front of this stretcher; this was to look more fance and to match up with the buffer beam.

The boiler of the traction engine is too long but, as the surplus length is dummy there is no problem.  Drill out the 2 rivets and pull the smoke box off the boiler. You will see a bulkhead with a big hole in it. Measure the length from the front of the boiler back to the real front of the boiler.  Deduct about 7 mm from this and mark this dimension around the boiler shell and carefully cut it away,  Then you can refit the smoke box, using new rivets and taking care to get it lined up accurately so that the boiler top is not drunken.

Now you can try the fit of the boiler - you will find the firebox is too high from top to bottom (if you see what I mean).  I cut away the lower portion of the front, sides and back so that the boiler sat level on the frame.  Careful work with a piercing saw!

Then you have job of supporting the firebox.  I used two lengths of ½” x ½” x 1/16” brass angle each side, screwed together to form a Z shape with 90 degree angles.  The lower ones are cut away to clear the wheels and screwed inside the frames, they are cut and shaped to fit inside the firebox,  The upper angles are shorter and the firebox sides are screwed to these.  Hopefully the pictures already on this thread will make this clear.  The screws holding the firebox to the angles (3 each side) are the only fixings, the smoke box simply rests on the front stretcher.

I intended to use the Mamod traction engine gas burner complete with what Mamod call the cowl.  To suit this I cut away the rear of the frames for a length of 70 mm to reduce the frame to a depth of 13 mm.  If I had not done this I thought the final loco would look way too tall, more like 7/8” scale than 16 mm.  This was not a total success and most of the cowl has been cut away and replaced with a sheet brass open cab.  The burner is from Forest Classics and is larger than the Mamod one, for the time being I have retained the Mamod gas tank,  The burner is carried in a ¼” brass vertical stretcher.

The frames are spaced 43 mm apart.  This gives enough clearance for the wheels but keeps the overall frame width as small as possible so as to avoid problems with lining up the sprockets on the crankshaft and first shaft.  If using wider spaced frames or 45mm gauge I think a special long crankshaft might be needed.

It is important to note that, with my spacing,  the wheels are so close to the frames that all fixing bolts must be kept clear of the wheels.  Yes, I found out the hard way,  Incidentally, my wheels are standard loco wheels from Roundhouse Engineering.

I hope all that won’t put you off having a go, it’s all part of the fun of modelling.
shiphayhill

Traction engine to locomotive

Today I put it back together and gave it a run.  It went quite well but, to my mind, is still a bit short of steam.

I don't think I will be putting any more notes on this thread, except to answer any queries or if I decide to go mad and build a better boiler, made of copper and silver soldered.

To my mind the Mamod boiler has problems, such as it being a silly idea to have the safety valve, which has a flat flange, screwing down against a boiler bush which is curved.  This means that the o-ring seal is under varying amounts of compression and it is no wonder that the bushes are loosened by overtightening in attempts to get a good steam-tight seal.

Dave Cracknell has a conversion which is built from (I think) the Pretania Foundry kit, with his own ideas incorporated.  I can vouch for the fact that his runs very well - I have seen it at the 16mm Association annual show in Exeter.

Happy modelling to all.
made-in-england

Mine runs... althoug today it was a bit of a bitch with some chain issues!
Dr. Rog

Re: Traction engine to locomotive

shiphayhill wrote:
Today I put it back together and gave it a run.  It went quite well but, to my mind, is still a bit short of steam.

I don't think I will be putting any more notes on this thread, except to answer any queries or if I decide to go mad and build a better boiler, made of copper and silver soldered.

To my mind the Mamod boiler has problems, such as it being a silly idea to have the safety valve, which has a flat flange, screwing down against a boiler bush which is curved.  This means that the o-ring seal is under varying amounts of compression and it is no wonder that the bushes are loosened by overtightening in attempts to get a good steam-tight seal.

Dave Cracknell has a conversion which is built from (I think) the Pretania Foundry kit, with his own ideas incorporated.  I can vouch for the fact that his runs very well - I have seen it at the 16mm Association annual show in Exeter.

Happy modelling to all.


Curved boiler bush? I have about 40 and I don't think any are curved.... I shall look.
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