Hornby 0-4-0 gears. The next step

[Bufferstop]

Just had a eureka moment, searching through my "might come in useful" box I discovered a gearwheel which was the same diameter as the one from the Hornby 0-4-0 but had a finer pitch. It meshed properly with the worm from a Thomas/0-6-0 motor. After a bit of head scratching I worked out that it came from a Hornby first generation motor bogie (ex Triang 2nd gen) and that I should be able to find at least 1 more of these gears. Now to see if one of these gears plus on 0-6-0 motor will cut down the headroom required in the 0-4-0s and make any difference to the low speed running. Also look into the possibility of opening out the 0-6-0 worm from 1.5 to 2mm to fit the 0-4-0 motor which seems to me to be a better product.
John W
aka Bufferstop

[GeraldH]

This sounds very interesting. Keep us posted and some pictures of the finished loco would be interesting. I guess that Ultrascale might have some suitable gears, but they would probably cost more than the loco

Hornby's smaller motor, used in the Pacer, seems more controllable at low speeds than the one in the current 0-4-0s - perhaps one of those could be slipped in?

[Bufferstop]

I don't have a target loco yet, I'm just exploring avenues of possibilities, But I'll be on the lookout for a spare chassis.
I've taken the next step, I decided to see if I could open out the worm with the 1.5mm bore to fit the 0-4-0 motor's 2mm shaft. First thing was to find a way to check the concentricity of the bored out worm -
This is the test I devised using the Johnson motor, I marked the armature pole pieces with a fibre tip pen like this \, \\, \\\. then is selotaped the motor to a piece of flat alloy strip. For the time involved it would probably be all right to use steel strip. Then using my digital callipers I measured from the underside of the strip to the top of the shaft, just ahead of the knurled bit, doing it a couple of times with each polepiece visible in the open side of the motor. The variation was less than 0.1mm. After drilling out the worm I fitted it to the shaft and putting a piece of thin plasticard over the teeth of the worm I repeated the test. The variation was still less than 0.1mm. So my method of drilling out the worm would seem to be acceptable. So here's how I drilled it out.
I thought that if I took off the minimum at a time there would be less chance of the drill going off line. I wrapped the worm with a strip of paper towel and gripped it gently in the jaws of my bench vice. If you are careful you might get away with holding it between finger and thumb. I set the speed on my "Dremel look alike" to about 30% and using a 1.6mm bit, drilled in about a third of the length of the worm, then I pulled out the drill to clear the swarf and took the worm out of the vice. Holding the worm between finger and thumb, in my left hand, with the tool turned off I put the worm onto the bit, and gripping the chuck with my right hand turned the chuck by hand. Each time I felt the drill biting I pulled it back cleared the swarf and repeated the process until the tip of the drill was just visible in the end of the hole. Then I replaced the bit with a 1.8mm one and repeated the process only doing the whole thing by hand. Finally I used a 2mm bit, again stopping when the tip of the bit was just visible. Using the above test I checked that the worm was still concentric, and powering up the motor there was no visible wobble on the worm.
Next step - look for another 0-4-0 that might benefit from some mods.
John W
aka Bufferstop

[Bufferstop]

Found the gear it's S8042 / X8042 see hear

[ngresley]

Found the gear it's S8042 / X8042 see hear

When I click that link, I can see it but I can't hear anything

[Dad-1]

ngresley thats cruel !!

I can understand Bufferstop getting so excited at the thoughts of a reasonable running Hornby 0-4-0
his spelling went to pot ...... or was that what we were supposed to be doing in the 1960's ??

Although I can get 2 - 4 scale mph out of 0-4-0s it would be much nicer if the motor turned faster
so I'll also be watching. John, I believe you 'did' the old Dock Shunter. I've just found mine and have
thought about trying to add a Black Beetle, or summat like, to make it useable on a DCC track. Think
my knurled wheel version is ..... perhaps a little long in the tooth !!!

Geoff T.

[GeraldH]

I've been playing with another 0-4-0 myself recently and I have noticed that you can improve the running quite a bit sometimes just by getting everything aligned correctly. A bit of extra weight also helps. I think they are put together pretty quickly in that factory

On one of mine the soldered joint on a motor contact was slightly out of place which meant that the motor was not in level/straight. This meant that extra power was required to get the motor to overcome the extra friction causing kangaroo running. I've also noticed that putting a 2mm washer on the screw under the motor support block can reduce friction also improving things.

[Mountain]

Converting to use a Triang 0-4-0 chassis can also be done if one is using a different body (E.g. for 7mm narrow gauge). The axle spacing is the same.

[Bufferstop]

ngresley thats cruel !!

I can understand Bufferstop getting so excited at the thoughts of a reasonable running Hornby 0-4-0
his spelling went to pot ......
Geoff T.

Actually Geoff it's a downside to using my tablet's spell checker. - it automatically applies the Google AI checking which I suspect isn't always totally autonomous, it sometimes makes substitutions for perfectly good words with other words which might be expected to come up in conversation. It's major annoyance being that it can do it many seconds after you typed in the word. I've spotted it having happened in other peoples posts. One thing the AI get's right in a logical way which is an annoyance for a modeller is changing the units of a scale model to ones more plausible for the real thing, substituting metres for millimetres for example. You just gotta watch these 'ere machines, they get power crazy if you don't speak sternly to them.

[Dad-1]

Reply to 26th February 2012 ???????

Mountain must have been trawling history ?

However regardless of the year It's reasons like that that I hate computers
more with each passing year.

Geoff T.

[RAF96]

The DMU 101 gear swap has been known about for several years but the problem is finding them.

2013 - see here https://www.rmweb.co.uk/community/index ... ent-993729

[heda]

One of my current projects is to get an old Hornby 0-4-0 running at a controlable shunting speed without going digital.
To keep the motor turning at a decent speed without the loco racing off the only way I can see is to change the gearing. So as 0-6-0's don't seem to suffer the same speed problem I'm planning on fitting 0-6-0 drive gear.
The cog on the 0-4-0 has 20 theeth, the 0-6-0 has 40 teeth although the worm has a finer pitch. I'm assuming the motors and axles have the same diameter shaft, if not it shouldn't be a major job to drill or fill .
Got to be worth a try for £5 but there must be a snag it seems to easy, can anyone see any obvious pitfalls.
Dave

https://www.ebay.co.uk/itm/X8199-Hornby ... 1316955238

[Kindling]

There may be a problem. The gear wheel of the two X8199 gear sets I have is 16.58mm diameter, but I also have older gear wheels which are 16.8mm. My only modern 0-4-0, a GKN with darkened wheels, has a wheel diameter of 16.78mm, so you may just about get away with it using a new X8199.

However, I have an old Holden 0-4-0 which has a wheel diameter of only 16.33mm, and a few Triang Nelly/Connie/Pollys, wheel diameter 16.25mm., so it will not work with old plastic-chassis 0-4-0s, which obviously need it most.

[heda]

Aah, that's the snag, I thought it was to easy the gear on the 0-4-0 (R255) is only 11.4mm so around 5mm difference, might work if the motor could be shimmed up 2.5mm but not quite as straightforward as I'd hoped.
Back to the proverbial drawing board for the time been.
Dave

[heda]

I have found the S8042 gears at a good price too. As Bufferstop says in the original post they are the same diameter as the existing gear on my old 0-4-0 but with 26 teeth rather than 20. I've ordsered some. Link below.
Dave


https://www.ebay.co.uk/itm/TRIANG-S8042 ... 3786265095