Triang class 31/37 power bogies

[john new]

4 hours ago, kevinlms said:

WD40 does affect some plastics, but not immediately. 

The general problem is that the plastic goes brittle and disintegrates.

So you can service all your fleet of models and all is well for a year or more, then...

Aware of that issue, what I was pondering was how effective tiny amounts are as a penetrating/loosening aid. What works on a 10mm nut and bolt doesn’t necessarily scale down to a 1mm screw.

[kevinlms]

On 30/10/2023 at 23:41, john new said:

Aware of that issue, what I was pondering was how effective tiny amounts are as a penetrating/loosening aid. What works on a 10mm nut and bolt doesn’t necessarily scale down to a 1mm screw.

Experiment and report back!

[DCB]

I would support the bogie frame firmly and tap the screw with a  hammer and pin punch then put the screwdriver on the screw head and tap the end as you try to loosen the screw.  As a final step break the plastic away and grip the edge of the screw with a pair of pliers.  Warming the bare frame with a small blow lamp might help, but  I don't recommend WD 40  Its a water dispersant,  we used to get Minis and the like going when they got damp by  spraying with WD 40.   WD dries out and leaves a coating of gunge, Its great for ruining clocks and watches.   They work for a week and then need complete dismantling.   Spray  3 in 1 oil is a better lubricant, 
Bogie frames are almost worthless so if the screw breaks get another frame on eBay.   Using a second metal frame for the trailing bogie improves appearance (but not as much as changing to Lima bogies)

[stewartingram]

WD40 - the ultimate bodger's tool. Penetrating oil should normally be used, though I'm not sure whether it will affect plastic. The tip of tightening first is a good one. Also, more important with the screwdriver and a cross-head screw - USE THE RIGHT ONE. There are/were 2 main types (especially back in the era of this model).Generally everyone seems to think Phillips head, this has only 4 slots. But more likely it could be a Pozidrive. This has 8 slots, and a different angle to the point. ((Of course nowadays there are a number of far East cross-points to complicate matters).

Also BTW 3-in-ine oil also affects plastic.

Edited November 2, 2023 by stewartingram

[andyman7]

3 hours ago, stewartingram said:

Also BTW 3-in-ine oil also affects plastic.

YES - 3-in-1 is absolutely lethal to the keeper plates and plastic 'top hat' brush holders on these motor bogies. Use it and in a few years they will just disintegrate! 

[kevinlms]

3 hours ago, stewartingram said:

WD40 - the ultimate bodger's tool. Penetrating oil should normally be used, though I'm not sure whether it will affect plastic. The tip of tightening first is a good one. Also, more important with the screwdriver and a cross-head screw - USE THE RIGHT ONE. There are/were 2 main types (especially back inthe era of this model).Generally everyone seems to think Phillips head, this has only 4 slots. But more likely it could be a Pozidrive. This has 8 slots, and a different angle to the point. ((Of course nowadays there are a number of far East cross-points to complicate matters.

Also BTW 3-in-ine oil also affects plastic.

Yes, most think that Pozidrive & Phillips are the same thing, they are not and the correct screwdriver should be used.

[john new]

On 01/11/2023 at 12:56, DCB said:

I would support the bogie frame firmly and tap the screw with a  hammer and pin punch then put the screwdriver on the screw head and tap the end as you try to loosen the screw.  As a final step break the plastic away and grip the edge of the screw with a pair of pliers.  Warming the bare frame with a small blow lamp might help, but  I don't recommend WD 40  Its a water dispersant,  we used to get Minis and the like going when they got damp by  spraying with WD 40.   WD dries out and leaves a coating of gunge, Its great for ruining clocks and watches.   They work for a week and then need complete dismantling.   Spray  3 in 1 oil is a better lubricant, 
Bogie frames are almost worthless so if the screw breaks get another frame on eBay.   Using a second metal frame for the trailing bogie improves appearance (but not as much as changing to Lima bogies)

Thanks all for the tips already given.

 

As requested by @kevinlms above an update with the steps taken so far on the stuck screws/replacement keeper plate attempt:-

 

1) Several attempts to unscrew with miniature cross-point screwdriver - all failed.

2) Some GT85 added in hope it frees off any rust. No difference after three hours. 

3) Gentle tap on screw head, no difference to any of the four. All remaining stuck fast.

4) Realisation that as the existing keeper plate was already broken if it would come off then the answer should be pliers on the screw head. The existing broken plate disintegrated easily for removal.

5) Still unable to shift the four screws - more GT85 added and it is going to be left for a few days in the hope the GT85 does the penetrating oil trick it says it will on the can (First time I have tried it for this purpose).

6) The warmth of leaving it on a radiator for an hour to see if expansion loosens the screws not yet attempted as for obvious reasons the loco needs a bit of additional dismantling first to avoid any body warping from the heat!       

 

As a general point I hadn't noticed before that underneath the underframe block (Part S.6332) there is a Brush Traction builders plate neatly moulded in. A nice touch if invisible most of the time.                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

NB: The other fix this afternoon, and roughly still on topic, was an attempt at resuscitating a dead Hornby class 37 (Ex Lima version?)  bought untested from a local 2nd hand/book shop for £10 a couple of weeks ago. Although vendor had been told it ran when tested the following Monday it didn’t run on the club test track. Examined today, absolutely filthy wheels etc., and it now runs well after a good dose of GT85 and a small amount of wheel cleaning.

 

Edited November 5, 2023 by john new
A couple of typos corrected.

[uax6]

You could try putting the tip of a hot soldering iron on the screw heads, now the plastic is away from them. Often warming a screw is enough to get it unstuck.

 

Andy G

[john new]

32 minutes ago, uax6 said:

You could try putting the tip of a hot soldering iron on the screw heads, now the plastic is away from them. Often warming a screw is enough to get it unstuck.

 

Andy G

I was thinking along similar lines of putting a hot iron alongside the bogie frame to see if expansion can ease the pressure. In a real full size scenario a blow torch to warm things up could free it off. I haven't the right tools to accurately drill it out and re-tap the holes; again something the real full size mechanics could attempt. I am wondering if before I bought it (and I have had it a long time), a previous owner has forced small self tappers into the holes having lost the original Tri-ang sold screws. Annoyingly, before the original supporting plate broke it ran well on loan to my grandsons.

 

[DCB]

8 hours ago, john new said:

Thanks all for the tips already given.

 

As requested by @kevinlms above an update with the steps taken so far on the stuck screws/replacement keeper plate attempt:-

 

1) Several attempts to unscrew with miniature cross-point screwdriver - all failed.

2) Some GT85 added in hope it frees off any rust. No difference after three hours. 

3) Gentle tap on screw head, no difference to any of the four. All remaining stuck fast.

4) Realisation that as the existing keeper plate was already broken if it would come off then the answer should be pliers on the screw head. The existing broken plate disintegrated easily for removal.

5) Still unable to shift the four screws - more GT85 added and it is going to be left for a few days in the hope the GT85 does the penetrating oil trick it says it will on the can (First time I have tried it for this purpose).

6) The warmth of leaving it on a radiator for an hour to see if expansion loosens the screws not yet attempted as for obvious reasons the loco needs a bit of additional dismantling first to avoid any body warping from the heat!       

 

As a general point I hadn't noticed before that underneath the underframe block (Part S.6332) there is a Brush Traction builders plate neatly moulded in. A nice touch if invisible most of the time.                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

NB: The other fix this afternoon, and roughly still on topic, was an attempt at resuscitating a dead Hornby class 37 (Ex Lima version?)  bought untested from a local 2nd hand/book shop for £10 a couple of weeks ago. Although vendor had been told it ran when tested the following Monday it didn’t run on the club test track. Examined today, absolutely filthy wheels etc., and it now runs well after a good dose of GT85 and a small amount of wheel cleaning.

 

That leaves a replacement chassis frame.    I should have one or two, but no screws...
I have quite a few spare wheels (plastic axle/ gear type, and although it means removing the keeper plate  I found polishing the wheels by fitting them to a mandrel (Artists paint brush handle) in the lathe (or drill chuck) and spinning them against a file or emery cloth until the treads are burnished, makes them much less prone to picking up dirt on treads and wheelbacks where the pickups run, without affecting traction too much.   I sold quite a few sets then put the lathe away in the loft and haven't bothered to do anymore.     

[john new]

17 hours ago, uax6 said:

You could try putting the tip of a hot soldering iron on the screw heads, now the plastic is away from them. Often warming a screw is enough to get it unstuck.

 

Andy G

The screws are now out after a lot of wrangling. What finally worked was, as discussed above, application of a lot of heat pumped out by my 75w soldering iron and applied to the block and screw head as at that point there was an option to keep the iron in one place. Photo below shows that to aid any future readers of the thread. I think the screws (bolts?) now they are out may well be the originals as they are parallel on the shank not coned like a self tapper would be. Given they were screwed in so tightly I wonder if Locktite (or similar) had been used by a previous owner/even Tri-ang originally; they certainly were not going to come out by accident! Photo shows where I placed the iron as the corner allowed the iron's tip to stay in one place.

 

So the job got finished off with a bit of scaled down prototype practice - appliance of heat to expand the fitting to loosen it, albeit with a soldering iron in 4mm not a blow torch as in 12" = 1". Hoping this will help anyone facing a similar issue in the future. 

 

[stewartingram]

Just a thought (and I may have to wear a tin hat and protective gear after admitting this), have a very close look at the tip of the screw thread.

I'm thinking they may be "Taptite" screws which I have used on a number of occasions (I had a bagful gifted to me at work when they were in vogue with our company). In layman's terms they are a bolt which can be screwed into a blind hole and tap its own thread, and I have used them in the past in this same situation. You will note that thr first few turns of the thread taper slightly; also looking end-o of the shaft, the latter is not circular at the end but chamfered off in (I think) 3 'corners'.

The tapered thread allows the screw to tap its own thread, with the chamfer letting it feed into the hole.

If I am right here, this may have been one of my 'rescues' and I there owe you an apology!

BTW, Tapties are metric and Triang are Imperial (BA?) threads.

[john new]

Update = job complete and engine runs on plain straight track and my rollers. The crunch for it will trying it through more modern points than it was built for when I try it on the club test track. The jury is still out @stewartingram as to whether the screws are original Tri-ang or someone's later replacements. Looking through a magnifying glass they have a one thread taper but it is hardly noticeable. Now they have been freed off and reinserted they turn fine - my guess is either Tri-ang originally or a previous owner used Locktite or just too much torque when fitting them. 

 

Re the problem 37 with the more modern style of bogie - also now fixed (I hope). It needed a home made clip making to replace a life expired original. 

 

Edited November 12, 2023 by john new
Typo spotted on re-reading the thread.

[DCB]

On 06/11/2023 at 16:05, john new said:

The screws are now out after a lot of wrangling. What finally worked was, as discussed above, application of a lot of heat pumped out by my 75w soldering iron and applied to the block and screw head as at that point there was an option to keep the iron in one place. Photo below shows that to aid any future readers of the thread. I think the screws (bolts?) now they are out may well be the originals as they are parallel on the shank not coned like a self tapper would be. Given they were screwed in so tightly I wonder if Locktite (or similar) had been used by a previous owner/even Tri-ang originally; they certainly were not going to come out by accident! Photo shows where I placed the iron as the corner allowed the iron's tip to stay in one place.

 

 

I am sure all mine had countersunk straight slot screws.   I wonder if these had the right thread

 

 

On 12/11/2023 at 17:19, john new said:

Update = job complete and engine runs on plain straight track and my rollers. The crunch for it will trying it through more modern points than it was built for when I try it on the club test track. The jury is still out @stewartingram as to whether the screws are original Tri-ang or someone's later replacements. Looking through a magnifying glass they have a one thread taper but it is hardly noticeable. Now they have been freed off and reinserted they turn fine - my guess is either Tri-ang originally or a previous owner used Locktite or just too much torque when fitting them. 

 

 

The wheels should be fine on code 100  and may well suit code 75.  Back to back is the issue, I would put spacers each side of the worm gears to control side play and ease the wheels out along the axles if the back to back is too tight, and  my test axle only gave 13.9mm b to b.  I usually use 14.2 mm (sliding fit on a b to b gauge)  and 14.5mm (measured with a digital vernier caliper) is often quoted .     Just widening the b to b could make the worms and worm wheel run out of alignment  so the brass worm eats the plastic gear.

[john new]

6 hours ago, DCB said:

I am sure all mine had countersunk straight slot screws.   I wonder if these had the right thread

 

 

 

The wheels should be fine on code 100  and may well suit code 75.  Back to back is the issue, I would put spacers each side of the worm gears to control side play and ease the wheels out along the axles if the back to back is too tight, and  my test axle only gave 13.9mm b to b.  I usually use 14.2 mm (sliding fit on a b to b gauge)  and 14.5mm (measured with a digital vernier caliper) is often quoted .     Just widening the b to b could make the worms and worm wheel run out of alignment  so the brass worm eats the plastic gear.

Interesting comment re the flat screws, they were what I was expecting to find.

 

It ran ok apart from occasional stutters. I think a couple of the very tiny lugs holding the pick up pieces may have been snapped off in the past. Will examine at some point in the future, might even put metal wheels in the other bogie and rig up extras.

 

Thanks everyone for the input.

[New Haven Neil]

I've never seen a cross head screw on a Triang-Hornby loco, always slotted head.

[stewartingram]

I've had a small number through my hands.

[Halvarras]

Well done on finally getting them out! My experience of these motor bogies was that the screws were slotted flat-head type originally recessed into the plastic base plate, but these recesses so close to the corners made the latter weak and prone to breakage, so later versions did away with the recesses and the screw heads then sat on the surface - fortunately the heads were shallow enough to allow this.

But mine were all early production up to around 1970 - I don't know whether the final production runs up to the mid-1970s had cross head screws. If so these must have been close to the railhead but if they still cleared it, even if only just, then good enough!

[GWR-fan]

On 10/06/2017 at 01:16, kevinlms said:

Early cast bogie chassis were live & if you did as I did & tried double heading with a Jinty, you got a short if the Jinty was coupled to the power bogie. in one direction. If you turned it around it was fine. It's a long time ago & I can't recall which way around worked. The biggest problem was the mismatch of speed, so not recommended, anyway.

 

I had an issue with a coupling of two Blue Pullman motor bogies retrofitted to a freelance set of ten Hornby Pullman coaches to represent a "Brighton Belle".   I found the ten-car unit ran better with the two driving bogies in the centre,  however,  as the bogies were live then with one turned a short circuit developed.  Simple fix was to fit a large plastic hook/loop tension coupler to one bogie to replace the stock metal version.

[kevinlms]

33 minutes ago, GWR-fan said:

 

I had an issue with a coupling of two Blue Pullman motor bogies retrofitted to a freelance set of ten Hornby Pullman coaches to represent a "Brighton Belle".   I found the ten-car unit ran better with the two driving bogies in the centre,  however,  as the bogies were live then with one turned a short circuit developed.  Simple fix was to fit a large plastic hook/loop tension coupler to one bogie to replace the stock metal version.

Any method of reliably preventing a short, is a good one!