P4 Questions and Hopefully, Answers!

[WM183]

Hi all.

I am building a High Level jinty chassis in P4. I used the "P4" spacers, and the frames came out to 16.2mm outside width. The bearings and hornblocks, however, are a bit wider; 16.55 over the hornblocks and 16.7mm over the fixed axle's bushings. My axles (Gibson P4) are 19.93 mm long give or take .02mm. If I press the wheels on with my GW wheels press until the face of the wheel is flush with the axle center, the back to back is too narrow. Even if I press them so the back to back is right, there is less than .1mm clearance between the back of the wheel hubs and the fixed axle bushings. I can file the bushings back a bit, but 1: How long should the axles supplied with the wheels be, and 2: should pressing them flush with the GW press set the back to backs for me? I am using a 17.75mm B2B gauge from DCC concepts, if that matters.

I suppose I can carefully chuck the wheels in my lathe and skim a bit off the back of the center boss, but - I'd like to avoid that if possible.

Help!

Amanda

 

[Bob Essex]

This is why Mike Sharman just used to supply lengths of axle steel you cut to length yourself. No two wheel types have exactly the same thickness depending on the type and whether a boss is added onto the rear. None of Mike’s wheels had bosses on the back but it varies on other makes like Gibson’s where some do and others don’t which just helps the problems along….. For this reason I’ve never used a fixed spacer size width but varied it to suit the wheels used and the minimum radius the loco is required to get around. I also always like to have a bit of sideplay on a wheelset to allow for easy and free running. I’d adjust the chassis/bearings/ hornblocks rather than attempt machining the plastic wheel centres.

Bob

 

[WM183]

Hi Bob,
Thanks much. Alas, there's not much adjustment to be done, as I was at the final assembly when I discovered this. I will file the faces of the fixed axle bushing back and hope for the best, I guess. .2mm or so isnt much but I think I can get that and and have the B2Bs be ok. I hope so anyway. The High Level kit is designed for Gibson wheels, and the kits come so highly recommended I never thought to check anything. It slotted together so well it would hold itself in one piece even before soldering!

Tricky business, this P4.

 

[Mark F]

I have a similar project on the go which has reached this stage.


21.9mm axles giving a 17.7mm back to back.

 

[WM183]

Nice! What did you do for pickups?? Can I see them??

 

[Mark F]

Nice! What did you do for pickups?? Can I see them??

I've not done them yet.
I did start to fix the pickup wire to the brake blocks, but hadn't thought this through enough in advance. If I was doing another I'd use plastic rod for the brake shaft, which would make this possible. I was going to use carbon fibre rod for the cross bars.

 

[Eastsidepilot]

If the axles are parallel, i.e. not tapered, then if you have a lathe I'd skim the back off the wheel boss so that it's flush with the back face of the tyre,
this would give you some side play.

Col.

 

[WM183]

If the axles are parallel, i.e. not tapered, then if you have a lathe I'd skim the back off the wheel boss so that it's flush with the back face of the tyre,
this would give you some side play.

Col.

Hi Col (Colonel?)
They are indeed parallel axles, but I was able to get enough play (.3mm or so) by gently filing away at the outer faces of the bushings and hornblocks. Pickups are installed, and it runs - and runs well!

 

[Paul Cram]

I have found that the Gibson axles are too short for my P4 wheels by almiost 1mm. I have obtained some 1/8th rod to make my own.

 

[simond]

Carbon fibre rod is conductive, which may be helpful, but probably not in this case!

Glass fibre pultruded rod is not conductive, and is tough & stiff, and usefully, cheaply & easily available in millimetre sizes from fishing tackle shops - apparently used in making floats and lures.

It’s on EBay too.

 

[Jim smith-wright]

Having built quite a few High Level chassis with Gibson wheels, including 2 jinties, the axle length is not a problem I've ever come across. Most recently I've got a set of wheels for a 3f so I'll report back if it is a problem now.

 

[Lyndhurstman]

Hello
According to a quick Google search, on their J15 conversion, Brassmasters specify an axle length of 22.1 - 22.6 mm for Gibsons (the first length was from a post in 2014).

Cheers

Jan

 

[WM183]

For those following this, we have managed to get the Jinty together and running well. I just need a couple more long crankpin bushes to complete the build and then a bit of touching up of the body (it came to be with a few nicks and scratches of paint). Dunno what I will do with it, but hey, it's built!

Amanda

 

[WM183]

Next question(s)

Does the P4 society sell the type of track with premade plastic sleepers with chairs, where you just slide the rails in? Or is all the track they sell intended to be soldered? I can solder up PCB sleepered track, I'd just rather not. Also, does anyone know what their shipping charge(s) are to Europe? I have not joined the P4 society yet, but I would like to if they've got things I need. The 2mm society is very cheap (or free!) for shipping to Europe, but of course, the bits are much smaller!

Amanda

 

[Paul Cram]

There are 2 optins. Plastic sleeper bases to which you need to glue the chairs to and bases with chairs alrady moulded in both standard and guage widened varities. I don't know obut posting abroad.

 

[Jeremy Good]

Hi Amanda,

The Scalefour Society stores does supply Exactoscale Fast Track bases which are plastic moulded sleepers and chairs which you can slide rail onto to make up track panels/lengths. There are other systems available as well including plastic bases with separate chairs and a variety of ply-sleeper based options.

I've checked the stores page of the website and the postage comments are:

"Orders to the UK, Europe and BFPO addresses are charged a flat rate of £3.00 per order for postage and packing. Elsewhere, £5.25 is charged.

For certain heavy items, such as rail and some jigs, supplementary charges, additional to the standard postal charges are included in the item price. These are included irrespective of whether or not other goods are ordered at the same time."

This is a members only service but there are plenty of other benefits from joining the Society in addition to access to the highly efficient stores service.

I hope this helps.

Jeremy

 

[WM183]

Thank you Jeremy!

There are 2 optins. Plastic sleeper bases to which you need to glue the chairs to and bases with chairs alrady moulded in both standard and guage widened varities. I don't know obut posting abroad.

I meant the ones with the moulded in chairs. Those ones are easier for me - track building just is not one of my favorite things.

 

[WM183]

Hi Amanda,

The Scalefour Society stores does supply Exactoscale Fast Track bases which are plastic moulded sleepers and chairs which you can slide rail onto to make up track panels/lengths. There are other systems available as well including plastic bases with separate chairs and a variety of ply-sleeper based options.

I've checked the stores page of the website and the postage comments are:

"Orders to the UK, Europe and BFPO addresses are charged a flat rate of £3.00 per order for postage and packing. Elsewhere, £5.25 is charged.

For certain heavy items, such as rail and some jigs, supplementary charges, additional to the standard postal charges are included in the item price. These are included irrespective of whether or not other goods are ordered at the same time."

This is a members only service but there are plenty of other benefits from joining the Society in addition to access to the highly efficient stores service.

I hope this helps.

Jeremy

Thank you! That postage is very very fair, generous even. I will figure out my application and get one sent off =)

 

[Lyndhurstman]

@WM183
Hello
Be wary of Ratio P4 track bases - they pop up sometimes on EBay. I seem to recall discussions that they are actually EM.

Cheers
Jan

 

[WM183]

@WM183
Hello
Be wary of Ratio P4 track bases - they pop up sometimes on EBay. I seem to recall discussions that they are actually EM.

Cheers
Jan

Hi Jan,
Thank you for the heads up. I will get all track parts from the S4 society, for sure. I'd much rather support a society shop than some rando on Ebay, and until now, never knew Ratio made any track bits at all! For now I will just be making a glorified test track on a Ikea shelf, just to see how I get on with the track.