Split Chassis Woes - A Panoply of Issues

[Owen E]

Hello braintrust

 

In building a cheap collection of 2nd-hand trains, I've ended up with plenty of the rejects - notably tender-drive Hornby and split chassis Mainline/Bachmann. When you can get a decent detail engine for a tenner, you're more willing to take a risk on the mechanism! (And the tender-drive Hornbys are nearly all good engines, at least after servicing.)

 

Of my six split chassis engines, 3 have some sort of issue. (The other three - Bachmann A4 Golden Eagle and Lord Nelson Sir Martin Frobisher, and Mainline Hinton Manor, are all pretty good.) Advice/info desired.

 

*Mainline Patriot "Sir Frank Ree" - Ringfield-style motor. Slightly bumpy on the track. I've read of something called "jerky wheel syndrome" affecting split chassis types - could this be that? It otherwise runs...okay.

 

*Mainline Royal Scot "Scots Guardsman" - Ringfield-style motor. When working on it last night, it started by audibly drawing a lot of power but moving incredibly slowly (full power made it crawl). I then opened it up and checked out its magnet (measuring over 1000 on the magnetometer) and making sure its commutator etc were clean (they were from last service, when I gave it new brushes, too).  After putting it back together, it didn't move, though there was initially a low electric hum. This stopped after I moved it bit to see if anything was out of place. Is this a sign of failed insulation, or what?

 

*Bachmann 43xx - Cam motor and weird plastic/brass block. This intermittently runs very well and not at all - i.e. runs smoothly and looks great, and then stops and doesn't pick up at all (with no continuity through the wheels). This has, it turns out, a cracked central axle by the gear - would that stop continuity? I would expect it just to cause it to seize up. I have seen one guy who 3D prints these axlesets online so perfectly willing to look into that. (I bought this one for £20 or something, normally they're over £40 second-hand, a tenner on parts isn't inefficient if it works.)

 

Thanks in advance for help/advice (other than "use a hammer to fix it", which is tempting but not on the list of options!)

[Tony Cane]

 

With regards to the 43XX a similar problem and possible solutions was discussed on the following topic.

 

Mainlane ex GW 22xx 0-6-0

[Owen E]

I've hunted that one now, thanks. I did remove a lot of grease yesterday - including on the various springs which are a main conductor! I'll look again tonight. It's an overengineered design, though the circuit itself is clear. It just has a lot of awkward/weird parts compared to, say, the older Mainline-style design, or indeed X03/04 and Ringfield stuff from Hornby.

[DCB]

I put a post on about improving Bachmann split chassis locos some time ago.

Basically the wheels which have a stub axle don't make contact with the chassis. Grease and oil affect this. 

I added pickups between chassis and wheel backs, springy brass hung over the motion bracket or screwed to the chassis. I improved a B1  Lord Nelson, Std 4 and 03 diesel this way.

Bachmann split chassis usually if not always have square ended axles and square socket wheels so they stay at right angles to each other "Quartering" as its known.  The wheels can and do fall off but you can shove them back on. My last survived 20 minutes from new in the box to losing a wheel.

Mainline ones I have owned have round axle ends and the wheels slip round jamming the rods.  In my opinion Mainline chassis shuold be run to they stop and then binned.   My father in law used to take the motors out of Mainline chassis on the 43XX and Manor and push them with Hornby Tender drives, using loco pick up through the wheels and chassis one side and tender the other. That worked well but the tender traction tyres made the track filthy so they have been retired. One was fitted with Romford wheels with the tender drive and ran very sweetly. My Mainline 43XX and Manor ended up with Triang Hall chassis and Romford wheels and have run very reliably for the past 30 years or so.

Edited March 9, 2020 by DavidCBroad

[Owen E]

Yep, found that thread too. The pickup engineering seems a little hard for my current level of expertise, though perhaps I could learn to do it (I've learned a lot recently in getting into model trains!).

 

The Bachmann 43xx has square stubs, yes, and yes, the central one did slip as I got it out of the box for the 2nd time. But also easy to requarter, as you say. I should look at the Mainline axles to check there's been no slippage (it might explain Sir Frank Ree - a very slight slip might cause jerking that isn't immediately breaking the rods).

 

Not sure how to account for "Scots Guardsman", though...

[tarifa]

Why not replace the Mainline "Scots Guardsman" chassis with a replacement chassis.  I think they are available on ebay.

 

[34theletterbetweenB&D]

19 hours ago, Owen E said:

...Mainline Patriot "Sir Frank Ree" - Ringfield-style motor. Slightly bumpy on the track. I've read of something called "jerky wheel syndrome" affecting split chassis types - could this be that? It otherwise runs...okay.

 

*Mainline Royal Scot "Scots Guardsman" - Ringfield-style motor. When working on it last night, it started by audibly drawing a lot of power but moving incredibly slowly (full power made it crawl). I then opened it up and checked out its magnet (measuring over 1000 on the magnetometer) and making sure its commutator etc were clean (they were from last service, when I gave it new brushes, too).  After putting it back together, it didn't move, though there was initially a low electric hum. This stopped after I moved it bit to see if anything was out of place. Is this a sign of failed insulation, or what?...

These two are I think the same mechanism in essentials.

 

The description of the Patriot's running suggests to me that a side rod may be fouling. You don't want to run it like that as the next thing is that a wheel goes out of quarter - because they can slip due to the round stub axle ends - and then it is busted and essentially finished. Have the mechanism out of the body, and turn over at dead slow using leads to the chassis halves to supply power, and look for a rod catching. This is best done by having the mechanism inverted and looking down on the rods from the underside. The plastic slide bars a vulnerable part of the construction; if these are deflecting as the rods move that's trouble.

 

Cannot tell what's wrong with your Scot. Test the motor off the mechanism to see if it is any good - description suggests it's finished. If the rolling chassis pushes along smoothly with the motor removed, keep it as a spare to put the motor from the Patriot mechanism in, should that rolling chassis fall apart.

 

This is a salvage operation to keep something running until totally worn out is the bottom line, much as suggested by David Broad above. Very low grade mechanism construction and made about 40 years ago, they don't last if used to operate a lot.

[hallmodelspares]

Looked over your questions and here is some of my own thoughts

 

Of my six split chassis engines, 3 have some sort of issue. (The other three - Bachmann A4 Golden Eagle and Lord Nelson Sir Martin Frobisher, and Mainline Hinton Manor, are all pretty good.) Advice/info desired. A4s fairly good run them sensibly they last well. do watch doing wheel spins or for any sudden stops as that can help work them centre axles too much. Lord Nelsons had a few at least 6 different ones all good and still so when sold on. Manor had to rebuild with spare wheels i had the axles were starting to go.

 

*Mainline Patriot "Sir Frank Ree" - Ringfield-style motor. Slightly bumpy on the track. I've read of something called "jerky wheel syndrome" affecting split chassis types - could this be that? It otherwise runs...okay. Would also check the wheels are not suffering mazak rot. this can affect them in many ways. Some the wheel tread can warp, Causing the wheelset to wedge causing the motor to struggle it free. Also look at spokes on the driving wheels, they can distort and cause raised sections which rub on the loco con rods

 

*Mainline Royal Scot "Scots Guardsman" - Ringfield-style motor. As mention magnet is fine I suggest checking the spring covers on the inside a clean and try the screws around the motor block, there should be 2 screws either end. Sometimes they need adjustment to secure together enough to run. Make sure the chassis bottom plate brake shoes do not touch the wheels espically if rebuilt as I rebuilt the green patriot model with peter spare axles centres. These made the wheels sit slightly wider than the mainline centres. I would also check the gears have no chips or splits. The mainline body should fit the Bachmann version of the chassis. Not sure of recent Dcc version?

 

Bachmann 43xx - Cam motor and weird plastic/brass block. This intermittently runs very well and not at all - i.e. runs smoothly and looks great, and then stops and doesn't pick up at all (with no continuity through the wheels). This has, it turns out, a cracked central axle by the gear - would that stop continuity? I would of thought it needs a clean replace the axle from Bachmann around 3 pound from them with post for the set of three (if you know it use the model reference number ie 365-11a when ordering which should give you the right parts)

 

Hammer is tempting but not necessary here is my 10 year running scot (had new drive axles once and sorted a loose bogie wheel rim) but I like it a lot and is different and in a way better than the Hornby tender drive 4-6-0's finish and detail

 

Edited May 3, 2020 by hallmodelspares
forgot a title

[NFWEM57]

On 09/03/2020 at 18:22, DCB said:

I put a post on about improving Bachmann split chassis locos some time ago.

Is there a link?

[DCB]

19 hours ago, NFWEM57 said:

Is there a link?

Er, I can't find it.  Basically I put pickups from the chassis halves to the adjacent wheels.  The wheels have stub axles which should make contact with the chassis but don't. Mazak isn't a great conductor,  Dirt, oil and the burnt gunge from constant arcing  act as insulators. I screwed contacts to a Mainline  03 shunter's chassis halves after the Bachmann motor burnt out and wasn't available and that was 20 odd years ago and its hardly missed a beat since, previously it needed a prod every couple of yards.   The B1 and LN ran like three legged crabs with hernias until I attacked them  They now have pickups hung on the valve gear mounting blocks held against part of the chassis filed up to bright metal and leading and middle wheel backs by the spring in the shim brass. Shimming the wheels with washers to restrict side play on front and rear drivers helps if you don't have curves less than 3rd radius. Quite often just one pickup per side is enough as the coupling rods act as conductors.   With extra pickups you can oil the axle journals with proper oil not conductive stuff.

My Manor had the same treatment, and a standard 4   4-6-0.   The 63XX has the same chassis as the manor more or less. 

[rogerzilla]

Does anyone know of a source of good replacement "muffs" and gears?  The ones Bachmann sent me were far too loose on the stub axles of a Hall class (they said they were all like that) and the 3D printed ones I tried were too brittle and cracked during fitting.  I don't think I'd buy another of these locos at any price.

[andyman7]

On 25/05/2022 at 22:04, rogerzilla said:

Does anyone know of a source of good replacement "muffs" and gears?  The ones Bachmann sent me were far too loose on the stub axles of a Hall class (they said they were all like that) and the 3D printed ones I tried were too brittle and cracked during fitting.  I don't think I'd buy another of these locos at any price.

Quite frankly, unless I want a shelf/shed ornament, my practice with these locos is a take a pile of broken ones and try and build one or more good ones out of the bits. I have occasionally done this with auction lots of 'sold as seen' multiple engine lots. But I do not consider any of the split chassis locos to be suitable for heavy duty work at this remove - they are just not engineered for decades-long service.

Edited May 28, 2022 by andyman7

[adb968008]

Ive had some of mine over 30 years, some mainline locos are not much younger than me…. I keep my nice little fleet growing… 45691 Orion is on its second body and 3rd chassis, but the original box, tender, chassis base plate and safety valves are “as delivered” to me, dates back to me sending a cheque to Railmail for it back around 1981…. The only reason the body changed was my childhood fascination of using sellotape to remove the lining.

 

My “Heritage” fleet includes a Mainline 7827, 4358, 5764, 45691, 45540 in addition to Bachmann 850, 4771, 5552,  6990, 7819, 7822, 7828, 30861, 45596, 45690 (renumber),  67601, 75078 and a few Ivatt 2-6-2T’s, B1’s they all run fine, most of them date back before y2k.

 

Sure a lot of knackers are in the market after 30 -40 years thats hardly surprising, but its not end of the world, you can make axles from plastic rod from B&Q easy enough. The bubbling of plastic wheel centres is the pain I dont like, but ive seen that fixed too.

 

At this stage they are cheap fun.

Edited May 27, 2022 by adb968008

[Free At Last]

I have just converted a Bachmann Branchline Jubilee 'Galatea' to run on dcc, bought new on release, tested and been in the cupboard since. I tested it on dc and it ran ok and no problem with wheel centres. The only problem was with the tender wheels which had too much sideplay and were easy to fall out. I cured that with a tiny piece of 0.5mm plastikard pushed to the back of each axle hole. Hardly any slack now and runs round my curves ok.

 

I drilled an 0.8mm hole in each of the chassis halves for a piece of brass rod to solder pickup wires to and wired the motor and pickups through to the tender where I also installed pickups and an 8 pin dcc socket. The decoder was from one of my other locos that  has recently had Youchoos sound installed.

 

Thanks go to Hornby and Bachmann whose prices have convinced me to spend my money elsewhere.

[andyman7]

17 hours ago, adb968008 said:

Ive had some of mine over 30 years, some mainline locos are not much younger than me…. I keep my nice little fleet growing… 45691 Orion is on its second body and 3rd chassis, but the original box, tender, chassis base plate and safety valves are “as delivered” to me, dates back to me sending a cheque to Railmail for it back around 1981…. The only reason the body changed was my childhood fascination of using sellotape to remove the lining.

 

My “Heritage” fleet includes a Mainline 7827, 4358, 5764, 45691, 45540 in addition to Bachmann 850, 4771, 5552,  6990, 7819, 7822, 7828, 30861, 45596, 45690 (renumber),  67601, 75078 and a few Ivatt 2-6-2T’s, B1’s they all run fine, most of them date back before y2k.

 

Sure a lot of knackers are in the market after 30 -40 years thats hardly surprising, but its not end of the world, you can make axles from plastic rod from B&Q easy enough. The bubbling of plastic wheel centres is the pain I dont like, but ive seen that fixed too.

 

At this stage they are cheap fun.

Indeed, with imagination and effort they can be kept running; but that is a very different ball game from the original mechanism being capable of going on and on just with regular servicing and replacement of consumables!

 

I have just won 3 boxed Warships in an auction. Visually they look perfect but I suspect all 3 will have split axle gears that need replacing.

[GeraldH]

On 25/05/2022 at 22:04, rogerzilla said:

Does anyone know of a source of good replacement "muffs" and gears?  The ones Bachmann sent me were far too loose on the stub axles of a Hall class (they said they were all like that) and the 3D printed ones I tried were too brittle and cracked during fitting.  I don't think I'd buy another of these locos at any price.

 

Peter's Spares do replacement muffs and geared axles.  If mine are a bit loose I fix them in with epoxy taking care that there's no overspill which could break connectivity between the axles and the chassis. Superglue is in my experience too brittle.  Make sure everything is degreased before applying the glue.  Lubricate the axles with graphite powder rather than oil or grease, it can make quite a difference.  I have quite a fleet of split chassis locos on the BNR and I only usually give up on them if they have mazak rot, or parts have literally worn out.  Of course they're not up to modern standards, but I'm working on a budget and prefer older, simpler, models 🙃.

[Halvarras]

Ekmexhibitions sell replacement wheelsets for Bachmann split-chassis 43xx, Manor and BR 4MT (NB They state these are not suitable for Mainline).

 

https://www.ekmexhibitions.co.uk/store/STEAM-LOCOS-c65518505

 

I keep an occasional eye on their website, having ordered a few bits in the past, and they have recently, and helpfully, started to add dimensional information for these wheelsets.

 

No connection, just a happy customer drawing attention to an interesting and reasonably priced collection of spare Baccy bits - might be worth a rummage!

[GernBlanstonShow]

So I've worked on an early Bachmann 57xx and noticed a really important point with these split-chassis is to have a good conductive lubricant for the axles. The key is finding a conductive lubricant that is slick enough to lubricate, but thick enough to stay in place and not cause shorts. 

I like to use CRC 2-26 but I'm in the United States and not sure if CRC products are easy to get or even available at all in the UK, so it might be worth experimenting with different conductive lubricants to see what works well for you. When I fully cleaned my 57xx it still ran imperfectly with relatively high current draw, and when I added conductive lubricant that noticeably improved both running and current draw. I know some people in the past viewed conductive lube as a cure-all and tended to over-use it, but as I said you have to be deliberate with it as it can cause shorts. I like to spray it into a small container and apply it to the axle slots with a foam bud. 

 

Also I'm feeling the Split-Chassis pain as well, while the 57xx was overall solid the class 04 I picked up recently had both split axles and a motor that's hard to find and replace. It probably won't be the last time I get needy split-chassis locos. 

 

Edited June 2, 2022 by GernBlanstonShow

[andyman7]

Not quite on topic but I've just picked up 3 x Mainline Warships in unused condition. All the have split main drive gears - they can be replaced but it is another illustration that the Mainline/Kader engineering of the early 80s assumed a built in obsolescence.

 

I suspect that by the 2050s there will be need to be an aftermarket industry in replacement electronics for all our modern superdetail whizzy DCC Sound models, once the solder joints go dry and the electronic components degrade! 

 

 

[rogerzilla]

Yup, the unused Bachmann Golden Eagle I got recently split its axles within two hours.  Weirdly, I have a Lord Nelson of similar age that is still running fine.

[AndyID]

I've always assumed the splitting is caused by lubricant attacking the plastic but maybe not?

[DCB]

On 05/06/2022 at 20:33, AndyID said:

I've always assumed the splitting is caused by lubricant attacking the plastic but maybe not?

I'm not sure, The there are some bogies which have tubular axles which definitely split when they get soaked with 3 in 1 oil as do the J72  driving wheels and the black ones with centre flanges.   The white one s I think it is lubricant but in a round about way.  The Lubricant stops the wheel stub axles making good contact with the chassis halves , the current arcs and that heats the wheel which initially softens the axle and the wheel slips, next step is the axle becomes brittle and splits.    The "Bachmann" chassis have larger axle journals and square axle ends so the axle can be a looser fit. So loose the wheels of our Manor fell off after 30 minutes running from new, but they can be pushed back on.    The Mainline ones don't fall off, the quartering slips and they destroy their valve gear.  I saved huge amounts of hassle by either  a) demotoring the chassis and pushing it with a Hornby tender drive, or b) fitting a Triang chassis with Romford wheels, or  c) sticking it on eBay.

[NFWEM57]

On 02/06/2022 at 02:09, GernBlanstonShow said:

I like to use CRC 2-26 but I'm in the United States and not sure if CRC products are easy to get or even available at all in the UK

Available from RS Components 250ml for £15

 

https://uk.rs-online.com/web/p/lubricants/1826341?cm_mmc=UK-PLA-DS3A-_-google-_-CSS_UK_EN_Facilities_Cleaning_%26_Maintenance_Whoop-_-Lubricants_Whoop+(2)-_-1826341&matchtype=&pla-332049931823&cq_src=google_ads&cq_cmp=9771206611&cq_term=&cq_plac=&cq_net=g&cq_plt=gp&gclid=CjwKCAjw14uVBhBEEiwAaufYxyaCD2ebfBWxR4lp2i6WBbZh0PNK9k9MUG1MDaNABOl2de0UHcn9pBoCSEwQAvD_BwE&gclsrc=aw.ds

[NFWEM57]

I am converting several split chassis locos and either fitting new wheels from Alan Gibson on 6mm brass stub axles if the originals are 'swollen' and cannot have replacement centres fitted or, if serviceable, intend to drill out wheel to fit 1/8" brass stub axles and remove the excess from the back of the wheel.   Will fit additional pickups if using Alan Gibson wheels but electrical connectivity maintained if using original wheels. 

 

Drilling out wheel on a lathe with 6mm portion mounted in a collet before removing 6mm portion from back of wheel, again on the lathe with wheel lightly held in a chuck.  

 

[AndyID]

2 hours ago, NFWEM57 said:

I am converting several split chassis locos and either fitting new wheels from Alan Gibson on 6mm brass stub axles if the originals are 'swollen' and cannot have replacement centres fitted or, if serviceable, intend to drill out wheel to fit 1/8" brass stub axles and remove the excess from the back of the wheel.   Will fit additional pickups if using Alan Gibson wheels but electrical connectivity maintained if using original wheels. 

 

Drilling out wheel on a lathe with 6mm portion mounted in a collet before removing 6mm portion from back of wheel, again on the lathe with wheel lightly held in a chuck.  

 

 

 I have an old Mainline "Illustrious". I replaced the chassis with a brass bar, fitted a Sagami motor and "Romfordized" the drivers on one side by separating the tread from the wheel on the lathe and inserting insulation. I'm not sure I could get away with doing that again. I seem to remember it was a bit nerve racking 😀

 

I have also made insulating metal axles. The center is solid steel but the outer surfaces have insulated concentric bushings held in place with epoxy resin. I can't quite remember which loco I used that on. It might be a 3-rail HD conversion.