JLTRT Class 40

[HealeyMills]

If anyone could give me guidance on the motor/ traction choice for fitting to the JLTRT Class 40 I would be most appreciative. I have read this article (www.migoforum.co.uk/ JLTRT 40) regarding meshing issues and I am concerned about the motor and gears sold by JLTRT.

 

What is the significance of the Mashima motor reference/ part numbers eg 1833 or 1824? Is there a preferential one for O gauge diesel locos? Which is best suited for the JLTRT class 40?

 

I have been inspecting the Roxy Mouldings gear boxes (after looking at the JLTRT Class 40's built by Brian Daniels) and wondered which one is best suited - 13:1 or is this too low?

 

Where can the chains and additional sprocket/ gears be purchased from to drive additional axles as I would rather provide drive to at least two axles per bogie.

 

Finally, has anyone used Roxy Wheels rather than Slaters?

 

Many thanks for any help

Regards

Lee

[F-UnitMad]

IIRC the designations on Mashima motors relate to their dimensions in mm. So 1833 is 18mm wide by 33mm long, 1824 is therefore a shorter motor. What difference this makes to performnce I don't know, but 1833 is quite common for O scale diesels.

13:1 sounds fine for a gear ratio for a bogie diesel. I used Ron Chaplin gears which were similar ratio, and wired the Mashimas (1833's ) in series. This produces a really good crawl with not too fast a top speed; if you want a higher top speed and aren't so fussed about the crawl, wire them in parallel.

I've not used Roxey wheels myself, but I'm sure I've seen them in use/posted on here...?

 

Delrin chain and gears can be got from this Ebay Shop. (Satisfied customer etc)

[brian daniels]

Hi Lee

 

As you probably know I use the Mashima 1833 with a Roxey 13-1 gearbox and Roxey wheels these days. I use the 13-1 gearbox as a layout I use has some iffy controllers so to get any speed out of them I have to use a fast gear ratio. They run nice and smooth on other layouts, just don't open them up on full or you won't catch them! I have found with the Roxey wheels it's advisable to leave them as a set by not unscrewing all the wheels and mixing them up. I think they are done as a pair as I did mix mine up and the loco wobbled down the track like good un. After I had re-arranged the wheels a few times it was ok. I assume I mixed them up and eventually got them back on their proper axles. I get my Delrin chain from Easybuild who do coach and DMU kits easybuild scroll down the page to the Delrin chain. As you have said you have to drive at least 2 axles on a bogie or they won't pull anything.

 

If you are visiting the NEC show I will be demoing on the Rail Express stand if you want to look at my stuff.

 

Hope this helps

[HealeyMills]

F-Unitmad and Brian - what can I say, thank you for your replies. Extremely helpful indeed and a very quick response too.

 

A couple more questions if I may....

 

Which toothed sprockets are best used - do you use 12T? Does it matter which are used?

 

..and finally, I have just realised I don't know what size wheels to order either. I know that I need 2 sizes (pony and main wheels). Having researched the actual sizes as 3ft 9in and the 3ft 0in wheels (3ft 9in are made available by Roxey) I wondered which were used as a close approximation to the pony wheels...... Roxey 3ft 1in wheels perhaps??? I guess the difference is negligible (cringe) but just thought I'd check all the same as maybe someone recommends using the 2ft 8in wheels. Questions, questions, questions... sorry to be a nuisance

 

Once this is sorted I think I'm on my way. I have decided on the running number etc:

 

40118 xb LO BR Blue circa 1981, disc headcodes, no frost grille, Long-short-long boiler grills, two brackets either side of the door catches. I seem to recall 40118 had its number on one nose end too but I'm still trying to find a photo of this to confirm. If anyone knows anything I've missed or have a correction to the aforementioned please feel free to add to the list.

 

Hope to start a thread on the build as soon as I get started so you can all guide me through my errors

 

Many thank in advance

Regards

Lee

[brian daniels]

Hi Lee, I use 10 tooth as they are a bit smaller as there is not much room for the chain and sprocket over the front driving wheel, you may have to remove a bit of of resin bogie to get the chain to go over the sprocket. A bit of a pain but not the end of the world. Get the pony wheel from Slaters as they do the correct axle for the kit as it's a 1/8th one on the pony wheel. They ain't cheap but they are correct! If you use the Roxey wheels there is a bit of a mod worth doing as their insulation is not very big and the wheel bearing will as sure as eggs are eggs overcome it in time and give you a short. I put a 3/16th fibre washer (I think Roxey do them) behind the insulated wheel but you have to file down the wheel bearing by the washer thickness as there is not a lot of side play to except the extra thickness of the washer.

 

If you are going to the NEC/Warley show I can show it to you on a model.

[HealeyMills]

Brian, Thank you for the guidance - this is proving to be a huge learning curve at the moment.

 

I was just reading the .pdf document of the instructions provided on the JLTRT website regarding those pony wheels sets. The explanation of fitting did seem rather complicated so I shall heed your advice - slaters it is then (Slater Ref: B7836P wheels and axles according to JLTRT)

 

I see what you mean about the 3/16th fibre washer: 26022_JLTRT_02

 

I'm not sure what I am doing with regards to Warley yet, I would love to go but I may have to work and that is miles away in Aberdeen. I think seeing one of these models in the flesh may help enormously too. I will send you a PM if I am able to make Warley.

 

Many thanks

Regards

Lee

[boxbrownie]

Hi Lee,

 

Sorry for the late reply I have only just found this thread through a link from another

 

Brian's advice is solid, although I bought the power bogie kit from JLTRT which came with delrin chain and sprockets and having fitted them found there was no need for any clearance to be made but I have not counted the teeth number, I'll check this weekend.

 

The JLTRT power kit came with a Buhler motor which initailly I was going to replace with a Mashima 1833 (having used these before) but upon assembling the supplied power bogie I have found it runs very sweet and the slow crawl speed is almost imperceptable, I am VERY impressed with the unit. I did buy a ABC gears diesel power bogie for the Loco but having tried the JLTRT bogie I am sticking with that for sure.

 

One item I did change though was the slaters wheels (apart from the pony axle set), I too use Roxey steel wheels and find them superior in trueness and performance, even after dressing the slaters wheels and mixing and matching to get the best trueness from them they still wobble slightly, and besides when did BR fit plastic centres to the 40?

 

I found like Brian that the "insulated" side of the Roxey wheels run a bit close to the bearings for comfort (I had no shorts as such but better safe than sorry) so I used a couple of silica washers normally used for insulating transitors on PCBs, these have the correct inside clearance and are fairly large outside diameter but are extremely thin meaning I need not shave anything off the bearings to accomodate them, also using two together gives a little more "slippage" and less drag I felt.

 

 

Also I have sprung the centre axle by running a length of nickel silver .7mm wire from each driven axle across the top of the floating centre bearing, this gives a perfect light sprung action enough to use the centre axle also as a electrical pickup, and it feels better to, not just bouncing around in a sloppy hole

 

Thats as far as my build has got so far, I have been busy detailing/repainting and fitting sound to my Heljan 37 & 47 for the past few months, and now I have been seconded into helping my son fit sound to his newly under construction layout fleet of diesels.....problem is he is modelling 4mm , sure glad I am 7mm now, how bloomin' fiddly are these new high detailed 4mm models!

[keefer]

hi lee, when you mentioned it, i was sure i'd seen 40118 with small numbers on the front doors.

couldn't find any evidence, but did find this under a search for 97408 (dept. number for use on the crewe remodelling, i think?)

 

 

it's not very clear, but definitely has 40118 on the doors. perhaps they were only applied after the renumbering?

 

i'll have a further rake about see if i can come up with anything else

 

EDIT: saw this one -

 

which looks like it might have it, but not sure.

if it is there, then you would be talking late 1985 onwards - there's a few photos earlier in '85 where there definitely is no number (although it did seem to have a full set of headcode discs!)

[DerekEm8]

Lee,

 

Further to Keefers ref EDIT: saw this one - http://www.flickr.co...tos/4103332946/ above

 

I have this (poor) shot earlier the same day :rolleyes:

 

 

At least they show that both ends were numbered.

 

I think all the end numbers on the 974XX class 40's were painted by the same guy.

[HealeyMills]

Thank you for your replies - extremely helpful as always.

 

Keefer/ DerekEM8 - I think the number on the front of 40118 must have been when it ran as 97408. But thank you for your help, love the photos too.

 

Also I have sprung the centre axle by running a length of nickel silver .7mm wire from each driven axle across the top of the floating centre bearing, this gives a perfect light sprung action enough to use the centre axle also as a electrical pickup, and it feels better to, not just bouncing around in a sloppy hole

 

Boxbrownie - is there any chance of a pic of the aforementioned... seems like an excellent idea and something akin to an idea I saw on a JLTRT 40 running on 'Oldham King Street Parcels' at the Rawtenstall exhibition the other weekend.

 

Thank you once again for your help, hope to post some pics on my thread (7mm Diesel Class 40) once I get cracking next week.

Cheers

Lee

[boxbrownie]

Lee,

 

The delrin cogs supplied with the JLTRT power bogie are 10 teeth and clear the chassis fine, I checked today but forgot to photograph the suspension for you, I'll try to do that tomorrow for you.

[boxbrownie]

Lee, here is the very simple method of suspension, the wire is soldered to each bearing (only solder with axles installed, this ensures alignment).

 

The wheelbase is such that there are no issues with too much tension by soldering them all together.

[Ressaldar]

Hi Lee,

 

as an addition to Dave's suggestion, you could utilise the suspension spring as the current collector as well (on opposide sides of each bogie) then you would not need plunger pick-ups at all. Further, you can use the bogie swivel plate and it's through bolts to cut own the wiring even more. I hope the attached photos explain, although I left my centre axle as a 'floater'. The bearings were drilled for the collector wire and then soldered in and the wire soldered into the bolthead slot which then carried the current through to the swivel plate and via the pivot bolt, through a tag to the wire to the motor

 

 

 

 

 

Best of luck with the build

 

regards

 

Mike

[boxbrownie]

Hi Lee,

 

as an addition to Dave's suggestion, you could utilise the suspension spring as the current collector as well (on opposide sides of each bogie) then you would not need plunger pick-ups at all.

 

Yes, sorry I should have mentioned that....using the Roxey wheel sets only one side needs plungers, the other picks current from the axles via the bearings (using the bearing spring) you can see I have left a "tag" of the spring one side ready for the wire connection.

 

Also I find the slaters plunger pick-ups need the spring cut virtually in half, this easily mantains contact and reduces drag on the wheels to a negligible level.

[HealeyMills]

David & Mike,

 

Thank you for taking the time to explain and photograph your class 40 builds.

 

David - the method for keeping the centre wheel engaged with the rail is an excellent one and is perhaps a little more elegant but none-the-less as practical as I had previously seen. I must admit I really like the idea of the pick up techniques used with the Roxy wheels. At the moment I have some of the Slaters wheels but I think I shall be ordering some 3ft 9in wheels from Roxy. Where did you get your thin insulation discs from that you use to isolate the wheels from the bearings? Rapid?

 

I managed to source some 10T Delrin sprockets and after giving them a trial run I don't seem to have any issues with them touching the bogie frame at all.

 

Mike - thats an excellent method for getting the power from pickups/ bearings through to the bogie swivel mount (via the bogie fixing screw). I hadn't thought of that but I have read your thread many times over and had gleened the idea of using the bogie fixing brass bolt as a means of power distribution - excellent idea

 

Thank you to everyone that has provided help, its making the build so much easier... and dare I say it, rather enjoyable!

I can see why Mr Daniels builds so many of these kits now

 

Cheers

Lee

[boxbrownie]

I used item #261-283 from RS Components, its a transistor mounting kit and apart from the ten silica washers has ten of each of various other useful (or not) nuts/washers/bushes/solder tags in the pack.

 

You might be able to source the washers seperately but I have not tried that yet.

 

If you have problems a need the silica washers send me your address via PM and I'll send you a spare pack I have here.

[TimC]

I've just bought some mica washers off eBay. Unfortunately they are from Taiwan but the feedback score of the seller is OK and I've had no problems form far eastern suppliers before for small value components. I'll report back once they have arrived.

 

Search for:

 

 

15 pcs TO-3M1 Mica Washer 40.0x.25.0x0.1 Taiwan

 

[boxbrownie]

I've just bought some mica washers off eBay. Unfortunately they are from Taiwan but the feedback score of the seller is OK and I've had no problems form far eastern suppliers before for small value components. I'll report back once they have arrived.

 

Search for:

 

 

15 pcs TO-3M1 Mica Washer 40.0x.25.0x0.1 Taiwan

They seem a little large at 40mm diameter with a 25mm centre hole, the thickness is Ok though, or is that a typical englasian translation, a mix of metric and imperial?

 

Its those infernal extra "point marks" that confuse me

 

The washers I use are (from memory) approx 16mm diam, 5mm centre hole, 0.1mm thick

 

* searched on the RS site and found #250-8336170 MICA WASHER @ .75"x.313".......still a little large on the inside diameter (not too bad though) and outside diam is fine, price is £11.50 for 50........minimum quantity I am afraid, although they would probably last a lifetime, but not at the speed Brian builds them!

[TimC]

They seem a little large at 40mm diameter with a 25mm centre hole, the thickness is Ok though,

 

 

I will use the washers are a source of material only - should be more than enough for my speed of modelling in my lifetime!

[brian daniels]

but not at the speed Brian builds them!

 

I don't build stuff too quick do I

 

Thanks for the heads up on those thin washers, must check them out. I do have a lifetimes supply of fibre washers but it is a pain to file down the bearing to get them to fit. I mean it adds at least an hour to a build

 

By the way I am doing another JLTRT 20 on my workbench

[boxbrownie]

I don't build stuff too quick do I

Only at a ratio of about 50:1 to any normal mortal on here!

Thanks for the heads up on those thin washers, must check them out. I do have a lifetimes supply of fibre washers but it is a pain to file down the bearing to get them to fit. I mean it adds at least an hour to a build

A whole hour? That must DOUBLE your build time

By the way I am doing another JLTRT 20 on my workbench

There you go, depleting the JLTRT stock inventory yet again

[HealeyMills]

With regards to washers, would these do the job:

 

Nylon M4 washers (0.8mm thick)

 

or would they melt?????

 

Just a thought

Cheers

Lee

[boxbrownie]

Hi Lee,

No reason to think they would be affected by heat, just not enough friction there.

 

But they are still pretty thick at 0.8mm.........the Mica/Silica washers literally are wafer thin, without measuring I'd say approx 0.05mm, but then I am better with feet and inches

[HealeyMills]

Hi David,

 

Thanks for that. So 0.05mm..... in old money that'll be 0.00196850394 inches then

 

Cheers

Lee

[boxbrownie]

Hi David,

 

Thanks for that. So 0.05mm..... in old money that'll be 0.00196850394 inches then

 

Cheers

Lee

Give or take a ha'penny.........