P4 conversion of RTR bogies.

[doggeface]

To date my success rate coverting new RTR bogie units to P4 has been hovering around the zero point. The problem lies in the failure to get a unit which has a) a parallel pair of axles (in the x,y & z axes).
b) Finding a means of fitting new pin point bearings for Gibson wheels which result in a free running axle.

The alternative of scrapping everything and making up sprung bogies appeals but as I am still testing I think that the rigid units will show up my problems quicker - if I can persuade them to behave long enough to show up the same problem point (as opposed to constant random derailments).

As regards the fitting of replacement bearings to the plastic RTR bogie units --- I read that there is a tool for drilling out these holes, has anyone tried it or could maybe explain what it looks like?

Peter

[grovenor-2685]

The special tool is designed for cleaning out and deepening if needed the pin point, its not for producing a hole to take a brass bearing, you just need a 2mm drill for that.
SeeMicromark for an example.
What type of bogies are you working with? I have used both Bachmann and Hornby without any problems, see my website for a Hornby example.
Regards
Keith

[Russ Elliott]

Ultrascale sell a driller tool. Or make your own.

[David Thorpe]

I haven't fitted any brass bearings to my Bachmann BR Mk1 coaches, but there again Bachmann doesn't use them either. As they come there isn't quite enough space inside the bogies for P4 wheels, so i needed to carve/file away a bit of plastic. When there was enough room, I popped in the P4 wheels. Running is free and good.

DT

[grovenor-2685]

There seem to be several tools used for moulding the Bachmann bogies, some can take P4 wheels without any alteration, others are a bit tight as Davey says, I have been lucky in that most of mine were the first type.
Regards
Keith

[Mark Tatlow]

All but a couple of my coaches on Portchullin use the Bachmann bogies.

They all needed a bit of the inside face taken off in order to provide sufficent clearance for P4 wheels. This is a bit of a drag as the plastic that Bachmann use does not file away very easilly but it can be done.

I also add extra weight to the bogie, partially because I use AJ's secured to the bogie and without the weight I find the drag of the coupling can twist the bogie a bit. I also put a tiny piece of 10 thou microstrip across the bogie pivot point - just so the bogie can tilt back and forth slightly.

Two look outs I found though. The commenwealth bogie has a projecting damper that fouls on the underside of the solebar - so reduce its height a tad. Also, do not over tighten the screws that hold the underframe onto the body. I did and it slightly deformed the underframe so that the bearing plate was no longer flat, so the bogies tilted slightly.

[doggeface]

Thanks for triggering the action button in my brain! The modified axle is so obvious.
I have been using some new Hornby units which do seem to need rather a lot of material removed. Filing was getting me nowhere so the Dremel and mini end mill removed the surplus; I found then that the wheels cleared the irons but the 26 mm axles need more depth for free running. This has been true of all of my Mainline,Hornby and Dapol rolling stock. Needless to say I had sold off all of my Bachmann rolling stock before starting into P4 so maybe it will be worth buying in a couple of units to form up a test train. it is so iritating to have a loco which will go any and everywhere and a one coach train that falls off whenever the mood takes it!

Peter

[David Thorpe]

I found then that the wheels cleared the irons but the 26 mm axles need more depth for free running. This has been true of all of my Mainline,Hornby and Dapol rolling stock.

I don't know what length Hornby axles are, but I think I'm right in saying that the Bachmann coach axles are 26mm long, the same as Gibson P4 axles. As a result, unless you insist on using brass bearings (which i found unnecessary), there is no requirement for any further depth to fit P4 axles.

DT

[martin goodall]

In the case of Hornby bogies I found that their axles were 25.5mm over the pinpoints, and the bogies were moulded to suit. So I re-used the Hornby axles with the P4 wheels (actually EM wheels set to the P4 BB gauge), rather than trying to adapt the bogie frames to take 26mm axles. As Mark has pointed out, there is a need to take a little plastic off the inside of bogie frames to clear the outsides of the wheels. Some other obstructions, such as brake shoes, also got snipped off (and in my case were not replaced).

I cannot remember any real difficulty with the Bachmann Mark 1s. Lack of compensation is readily overcome by using EM wheels instead of P4. Setting one bogie so that it can rock sideways, but the other so that it can't, ensures that the coach won't wobble.

[David Thorpe]

Can't say that I've found any need for compensation on my Mk1s, even with P4 wheels.

DT

[doggeface]

Well men, inspiration arrived in Spades! I remembered that a couple of brand new Hornby 57's were in my stock box. They behaved just as described for the Bachmanns! Just as a back up though I grabbed a Bachmann off of ebay UK. After a thorough glaring at one of my tw Airfix Autocars decided to cooperate in push and pull mode so it looks as if I now have the means to debug the system as is to date! I probably will make up a Comet kit 57' (unless advised otherwise) in order to have a sprung vehicle in the test outfit.

Peter

PS I did take a couple of sunny weeks off in Sunny Spain in order to get away from the problems and was rather peeved on my return to find that nothing had fixed itself!

[grovenor-2685]

Can't say that I've found any need for compensation on my Mk1s, even with P4 wheels.

Quite, most of these have Bachmann or Hornby bogies with a wheel change, with 26mm axles and P4 wheels, I have not found that the bearing holes needed deepening.

Keith

[doggeface]

I have also switched a P4 wheelset to the older Hornby axles (25.5 mm long) . This gave free running but the instability remains -- I suspect a warped sole plate. The modern Hornby axles are 26mm long. The Airfix & Dapol axles are also 26mm long but the plastic axle box mouldings are thicker and require rather more reduction. It looks like sale time for the older Hornby units.

[21C141]

Following on from this thread, as I'm new to P4 can anybody tell me if the Hornby Maunsell conversion is straightforward or is surgery required for reliable running.

Ray.

[Andrew Ullyott]

Following on from this thread, as I'm new to P4 can anybody tell me if the Hornby Maunsell conversion is straightforward or is surgery required for reliable running.

Ray.

I managed to covert a pair for Wheal Elizabeth using Branchlines wheels without difficulty. I followed the EMGS data sheet to widen the bogies.

[21C141]

I managed to covert a pair for Wheal Elizabeth using Branchlines wheels without difficulty. I followed the EMGS data sheet to widen the bogies.

Thanks, AUIIyott, I've seen a few threads quoting a EMGS data sheet, seems strange I have to join the EMGS to get a data sheet to do a P4 conversion?

Ray.

[Philip Hall]

You don't actually widen the bogies, you just clip out the brake gear moulding, cut it in half and glue it back in line with the P4 wheel treads. No need to join the EMGS; just look in a recent MRJ - not sure which one, not long ago though - at Peter Swift's article on Hornby Maunsells and the method is shown there.

Philip

[grovenor-2685]

Its MRJ 213 page 75, and the process is pretty much identical to that for the Stanier bogies illustrated here, http://www.norgrove.me.uk/lms-bogie.htm
Regards
Keith

[Steve Carter]

Also here viewtopic.php?f=24&t=1182

[21C141]

Its MRJ 213 page 75, and the process is pretty much identical to that for the Stanier bogies illustrated here, http://www.norgrove.me.uk/lms-bogie.htm
Regards
Keith

You don't actually widen the bogies, you just clip out the brake gear moulding, cut it in half and glue it back in line with the P4 wheel treads. No need to join the EMGS; just look in a recent MRJ - not sure which one, not long ago though - at Peter Swift's article on Hornby Maunsells and the method is shown there.

Philip

Thanks Keith, (Phillip)
Only just discovered MRJ so don't have any back issues but from looking at your website it looks simple enough.
Am I to take it from this that a compensated bogie is not necessary?

Regards

Ray.

PS Thanks for the link Waterloo, most informative. time to get some wheels and give it a try.

[grovenor-2685]

I have found the Hornby bogies to work well with just a wheel swap, both the Stanier and Pullman varieties, I would expect the Maunsell ones to behave similarly.
Keith
Pullman ones here, http://www.norgrove.me.uk/pullman.htm

[Paul Willis]

I managed to covert a pair for Wheal Elizabeth using Branchlines wheels without difficulty. I followed the EMGS data sheet to widen the bogies.

Thanks, AUIIyott, I've seen a few threads quoting a EMGS data sheet, seems strange I have to join the EMGS to get a data sheet to do a P4 conversion?

Ray.

Hi Ray,

You may not be aware that the EM Gauge Society caters for modellers in both P4 as well as 18.2mm gauge. Many finescale modellers are, like myself, members of both.

However as I'm sure that you've subsequently seen, there are also many other people here on the Scalefour Society Forum that also are able to help, and are very willing to share their time and experiences with anyone that asks a question.

There are, as with many things in P4 modelling, many ways to skin the (proverbial and unfortunate) cat so please don't be surprised at some of the answers that you may get

I hope that the bogie conversion goes well. As has been said, there are many others that have made these work successfully. How about a picture or two on here to show how you managed?

Cheers
Paul Willis
Deputy Chairman

[21C141]

Hi Keith, Paul.
Thanks again for the links, will order some P4 wheels and hopefully get some time over Christmas to try a conversion. Will post some photos of my efforts.

I did have a look at the EMGS website but its not as open to browsing as the Scalefour site. No try before you buy! But I guess it's another useful resource so will probably end up joining.

Ray.

[Tim V]

The manual sheets are not (yet) on the EMGS website. Their (paper) manual though is excellent.

[21C141]

As requested by Paul, here's a photo of my first Maunsell bogie conversion using the procedure described by Keith. I used Butanone to reassemble the parts.

image.jpg

Just need a layout now to try it out on.

Ray.