Trade SDMP/Finney7 - Driving a Geep?

[Steph Dale]

Goodness - six months since I last posted. There's been a good bit going on...

For a start I think I've given up on the T1; although it looks as thought it could be made up quite sensibly into a T1 it just doesn't have the necessary finesse or detail for me to feel it was worth giving it a set of inside motion. So it'll disappear via Ebay or a Bring and Buy or somesuch. I'll have to think about another suitable loco to use to test the 'RQN' gearbox.

Ah yes, gearboxes, I knew there was a reason for me to update this thread. Things have been moving along and the diesel drive 'boxes have now been test built at Mk2 status. It's taken a while to get this far, but it's worth it; set up is now very much simpler than it used to be and it just goes to show that I do listen to feedback I receive. Incidentally, existing owners of the original diesel drive boxes can upgrade for a very advantageous price if you like what you see, 'cos I'm good like that. Just drop me an email or PM if you read this...

So this is what the 'Power 13:1' version now looks like (on the right), with a Mk1 for comparison. Changes include a slightly stronger frame that's a full fold-up rather than two-part. I've also completely abandoned use of the additional head bearing; most of the feedback I got was that this wasn't necessary. Motor fixings now use a motor twist to fine-tune the gear mesh, although that has meant that only 12mm and 15mm M2 fixings are now provided. Yes, the Mk2 has been blackened and no, it didn't go swimmingly, although it can now be done without risking the bearings:


The 'Remote 13:1' has been subject to more significant changes. One issue we've had has been that the gear mesh centre isn't constant; changes in shaft dimensions, reaming of the bearing seatings and the gears themselves all affect the ability of the gears to mesh absolutely perfectly. So the solution was to try and find a way to separate the gearbox into components such that the mesh can be fine tuned. A bit of thinking resulted in what you see here - even using the same screwdriver you need to build the 'Power' version; how's that for forward-thinking? Again the Mk1 is on the left the Mk2, with shameful metal blackening, on the right:

Incidentally, all my gearboxes are now provided with the frets reamed to take the bearings so you can just fold 'em up with some care, solder, clean and assemble, an M2 tap being the only piece of specialised equipment necessary to assemble the 'Remote' version.

The first set of these Mk2 gearboxes are destined to go in my MMP 56, which made me think a little about other desirable traits for diesel locos, resulting in this etch:


This includes a couple of cosmetic parts; such as the different cab backs for each end of the loco, together with glazing seal, hinges and lock. There's also a fold-up for the bogie's external compensation beam. But the main focus of the fret is a number of beams, spring clips, jigs and a new bolster to give CSB-style primary and secondary suspension. I'm intending to do a few more bits and pieces for Class 56s, including multi-depth etched grillework. Just guilding the lily really; I still think it's a fab kit.

Steph

 

[SimonT]

Steph,
A few questions:
Will these fit into a JLTRT resin bogie centre?
Will the second axle will still need a Delrin drive?
Will they fit onto a Buehler motor and replace a 40:1 gearbox as currently fitted?

Thanks
Simon
(Currently fitting mossive speakers into the locos for RailEx, so I might as well do another mod at the same time. Yeah, we got bass baby)

 

[Ian G]

Simon I dont think you can fit big enough speakers in your locos to be heard at |Railex

Ian G

 

[SimonT]

Well, I admit that they are not as big as the ones that gave us bird song last year!

 

[Steph Dale]

Steph,
A few questions:
Will these fit into a JLTRT resin bogie centre?

There's no simple answer to that; not in the 50, yes in the Western, a qualified maybe in the 37 - what loco are you asking about?

Will the second axle will still need a Delrin drive?

This drive assumes use of a prop-shaft with the motor horizontally in the bogie. But I can help by other means if you like Delrin chain...

Will they fit onto a Buehler motor and replace a 40:1 gearbox as currently fitted?

Got a picture? It depends a little on the motor; if it's got a 2mm shaft and M2(ish) fixings at 10, 12 or 15mm fixings then yes. Otherwise it's a qualified maybe!

Oh and do check back shortly. My posts to this thread tend to be a bit like buses...

Steph

 

[Dog Star]

Steph,

Will these fit into a JLTRT resin bogie centre?
Will the second axle will still need a Delrin drive?

There's no simple answer to that; not in the 50, yes in the Western, a qualified maybe in the 37...

This drive assumes use of a prop-shaft with the motor horizontally in the bogie.

Steph,

I believe that you have a couple of JLTRT diesel kits... how about a picture of your motor / cardan / gearbox fitted into the JLTRT resin bogie inners so that we can see your solution in the real estate?

 

[Steph Dale]

Graham,

Didn't manage it in the 50 at all as the bogie is too narrow and weak, the Western is on my thread here (no further progress to report) and the 37 wasn't done by me...!

This Mk2 version is a genuine 'Mk2'; the initial version is no longer available. The Mk2 does the same job, in the same space, more easily than the old one did.

Steph

 

[Steph Dale]

More good news...

Today there was a consignment of gears from Markits, this puts all the Romford/Markits gearboxes into stock for the first time. It's a situation I intend to continue. With this arrival, I now have ratios of 13:1, 20:1, 26:1 and 40:1 (including a '2-stage' variant of the latter) available in the new Markits range and 30:1, 40:1 and 54:1 in the Romford range. :


In a couple of PMs today the question of DMU drives has been raised again. There are a number of options, but the Markits delivery makes the 13:1 gearbox for the Mashima 1430 available for the first time if you like the version I showed up in post #262, at that point the gearbox was a 'special'. Of course versions are also available if you want to use Mashima 18xx or Canon 1833, including diesels with Delrin chain drive.

Coming back to DMUs again for a moment; there's also the option of a proper cardan shaft drive. With half an hour at the computer this evening I did a quick CAD sketch which confirms that this drive will work at well under 6' radius using Branchlines universal joints and that the theoretical limit isn't reached until the 4' radius point!

The large circle is the bogie centre, the dotted line the centreline of the DMU (measured from an EasyBuild Bubblecar kit). The issue of concern here is the small dark (it's actually blue!) circle, which is the universal joint on the inner end of the bogie. In this drawing (at 1800mm radius so a little under 6') this is at 11 degrees; the theoretical maximum of 15 degrees is reached around 4' radius. I'm aware this drawing isn't particularly clear so for those who are interested a 'tidied' version can be made available. This sketch is assuming the use of the Mk2 'Remote' gearboxes on the inner axle of the bogie, Branchlines universal joints, a motor of choice and some shaft/tube to lengthen the motor shafts so they can be well hidden.

As part of that solution (and I can't remember whether I've shown these before), I do a motor bracket for Mashima 1800 and Canon 1833 (Item MB01, including a bearing to support the back of the Canon motor) and driveline brackets (Item DB01, including bearings not shown here) which allow the whole lot to be built up in a fairly straightforward fashion and screwed to the underframe of your chosen DMU:


Steph

 

[SimonT]

Steph.

There's no simple answer to that; not in the 50, yes in the Western, a qualified maybe in the 37 - what loco are you asking about?

Certainly the 37s and then the Western and Peak.

if you like Delrin chain...

I loathe Delrin, especially having spent twenty minutes trying to get a chain to join back up after some bogie servicing today.

Got a picture?

No but I took the chance for some measuring and it's a 2mm shaft and 2mm (ish) fixings at 14mm centres.

Oh and do check back shortly

Stop calling me shortly!

Looks like it is a mod done at a slow considered pace rather than in the run up to a major show. Now back to the blasted bogie as one of the Delrin cogs is slipping. Bah!

Simon

 

[Pugsley]

Coming back to DMUs again for a moment; there's also the option of a proper cardan shaft drive. With half an hour at the computer this evening I did a quick CAD sketch which confirms that this drive will work at well under 6' radius using Branchlines universal joints and that the theoretical limit isn't reached until the 4' radius point!

That has certainly piqued my interest. Do you stock all the necessary bits? If not, which Branchlines UJ's would I need, or is there only one type?

Perhaps the 108 will be the next 7mm project across the workbench after all!

 

[Steph Dale]

I'm still thinking about that, but suspect the easiest option would be for me to provide a complete kit including all the shafts, bearings, motor, etc.
What do you reckon?
Steph

 

[Dan Randall]

Perhaps the 108 will be the next 7mm project across the workbench after all!

I hope so - I have a soft spot for DMUs.


Regards

Dan

 

[Dikitriki]

I'm still thinking about that, but suspect the easiest option would be for me to provide a complete kit including all the shafts, bearings, motor, etc.
What do you reckon?
Steph

I think that a full kit is the best option. As someone who doesn't know this side of the market at all, I would rather have it all in one hit than have to source other parts to complete.

........so can I order 1 x complete kit for 1 bogie please.

Ta.

Richard

 

[Pugsley]

I'm still thinking about that, but suspect the easiest option would be for me to provide a complete kit including all the shafts, bearings, motor, etc.
What do you reckon?
Steph

Complete kit please. I know I could source all the bits myself, but it would take ages.

I would be awkward, though, I'd want all the parts to drive the inner axle of each bogie on the power car.

 

[Steph Dale]

Productive evening, which I thought I'd share before I turned in.
Test bed DMU bogie with single axle drive and picking up through the wheel bearings. This is an Easybuild bogie, so it's plastic and as you can see needed little modification to take the drive; a bit more carving was required to get the pickup wires in place which you can see coming straight out vertically. There's a very small amount more to do to get the bogie complete, which I hope to do tomorrow. I'll then update with more info...


Steph

 

[Pugsley]

Very nice - just the thing I had in mind!

 

[Steph Dale]

Quick update, the second bogie has been thrown together and a re-read of the Easybuild instructions revealed I'd forgotten to trim the end beams off the first bogie frame. So that was remedied and sections of 2.5mm square styrene used to beef them up. Of course scale end beams could be fitted, so too brakegear...:


You'll note that I used a different shape of torque-reaction arm on the second bogie; it's shorter, neater and doesn't cross the bogie pivot. As a result of the short length it's a bit trickier to fit, but in not crossing the pivot may be easier to fit to some manufacturer's bogies. Here's a closer look:


From underneath there's not a huge amount to show, other than a load of space:


And this shot confirms that there's a lot of space under there for the brakegear and bolster without a Delrin chain getting in the way:


This is how I'm anticipating the whole lot fitting together (if you ignore the two-axle drive on the right-hand bogie!). I'll raid the bits box tomorrow and see what I've got that can be used to get a prototype running. I know I've got the brackets, shaft couplings and motor, but less sure about the shaft material itself:

(Picture removed by edit - see post #295, below)

That's it for the moment, hope it's useful;!

Steph

 

[Scale7JB]

Lovely solution Steph..

JB.

 

[SimonT]

Steph,
this could solve the problem on my 117 where I need two power bogies to get it up the hill. Currently there is a power unit in the DMBS and in the DMS where it is very visible. The two chips have different start delays for which I cannot find a CV to alter. So, one motor driving all four axles on the DMBS would be a big improvement. In addition there would be room in the brake compartment for a decent sized speaker. Put me down for a set!

Simon

 

[Steph Dale]

Further proof, if it were needed, that it's always useful to read the instructions...

I've had a look at the underframe parts, bogie mountings etc, and realised they don't quite go together as I anticipated. So with ruler and parts in hand it was time to edit the sketch I originally presented in post #292, above:

Two slightly different views. The bottom one is actually the version I should have posted yesterday evening; it shows drive on two axles with the motor shaft extended through the use of drive brackets and shafts, aluminium tube being suggested. In this view the brackets for the motor and shafts are all suspended directly from the Easybuild underframe. This results in a drive which is simple to install and keeps the universal joints working at acceptable angles.

Looking then at the top one you can see it's pretty much perfect - the shafts are to all intents and purposes straight when the vehicle is on straight track. This is accomplished by fixing the motor and drive brackets to a new panel so that the top surface of the current floor becomes the datum - all fairly simple stuff, even if not quite as simple as the other view!

Martin,
On your 108, with its shorter underframe, you'd probably only need to use two shaft brackets, rather than the full set of three shown here. The motor could be central or offset to one end as you prefer.

Simon,
I agree that this approach can be easily extended to drive all four axles, although you would have to put a drive shaft across the bogie pivot. by no means an insurmountable problem though. So for you there are two choices - drive two cars, each with two axles driven or drive one car on four axles. If you prefer the latter would you want to use one motor or two? I'm just trying to work out what would be in your 'set'!

Steph