P&D GP9 Drive Problems

the issue is not with the P&D drive parts,  but the original Weaver sprockets. the acetal sprocket material was not aged and would split. if you don't have confidence in the P&D sprockets (I have had no problems with them over many years), you can also order them from Sterling Instruments.

My experience has also been that the original Weaver gears and sprockets were prone to cracking.    P&D has replaced the original weaver parts in their drives.   Also replacements I got direct from weaver when they still serviced them worked out fine.

That being said, you still might get a cracked gear or sprocket at some point.    Or some other part.

But the beauty of these drives is that yes you can do all the repairs and rebuilds yourself with a few hand tools and some patience.    You do not need a metal lathe at all to work on these.

I used NWSL wheel set, and they are working perfect, beside the brass bushing included.

Regarding the Fine scale 360 IMO is a big plus, because the chain links are, in some case not enough to adjust it properly so the chain will be too tight or too lose. 

my 2 cents.

Andre.

There's a lot of good info about this here:  

https://bobsobol.smugmug.com/T...PD-Drive-Train-Work/

I have shamelessly copied everything I learned there and from several threads on here with MaxSouthOz and others and it works great with the Finescale 360 chassis and drive upgrades. I recently added a Maxon coreless motor, Loksound Select HO decoder and Tang Band speaker to the upgrades on an RC GP9. My best running and sounding loco so far!   

I have done the yards on a Weaver, Stephen - and learned a lot in the process.

No special tools required. 

This might help . . .

https://ogrforum.com/t...first-attempt?page=1

Good Luck  It will be fine.

According to another post here on the forum, the Atlas gp9 frame will also work for this kit.  It stands to reason, as Atlas bought the Red Caboose tooling.  The Atlas frame shows in stock now at $14.95 each, although it does not include the pilots.  I can't speak to amending or attaching original drive components to the Atlas frame.  That may be more trouble than it's worth.

Atlas gp9 sill unit

Jim

As for the metal lathe I used, if you stick to P&D replacement parts you can do everything with just hand tools. I wanted to change the sprocket ratio for slower speed running. That helped when I used non-back EMF decoders. These days the motor control in the Loksound L is so good I won't change any more drives. The original drive ratio also produces less chain noise. 

Because acetyl shrinks over time, there have been outbreaks of cracked gears in many vendor's products, even in certain runs of HO locomotives. Over many years stuff happens.

Question for Pete - Which Tang Band speaker did you fit in your GP9 and where did you install it?

I might have some parts for free if you want them.

I looked at the Atlas frame on line in the parts list.   Based on the drawing, it does not look like the P&D conversion will be a drop in.   I think you will have to drill and tap the aluminum frame to install truck bolsters.    You have to cut and drill the original IM frame for this also.     And it looks to me like the pilots and steps install totally differently on the Atlas.   On the IM unit the pilot/step assembly is part of the shell and wold have to be cut off.    On the Atlas it looks they are separate parts that screw on.

As an aside, Des Plaines hobbies in Chicago (they have a web site) sell machined frames for these  units that fit the P&D drive and provide weight.   They are pricey, but nice.   I think 60-80 dollars apiece.

The P&D sprockets are quite reliable. Every Weaver sold had the sprockets changed before they were shipped out. No returns on those.

Hello Patrick.

I certainly would be interested in what you may have.  I have three Red Caboose kits (2 full kits and 1 body kit).  I am going to convert the two powered units to DCC (dead rail I think at this point) using Loksound Decoders, Des Plains Hobbies frames and P&D drives (none of which I have purchased yet).  My first attempt at DCC and first attempt with Dead Rail.

Sincerely,

Stephen Wilson

riogrande491 posted:

As for the metal lathe I used, if you stick to P&D replacement parts you can do everything with just hand tools. I wanted to change the sprocket ratio for slower speed running. That helped when I used non-back EMF decoders. These days the motor control in the Loksound L is so good I won't change any more drives. The original drive ratio also produces less chain noise. 

Because acetyl shrinks over time, there have been outbreaks of cracked gears in many vendor's products, even in certain runs of HO locomotives. Over many years stuff happens.

Question for Pete - Which Tang Band speaker did you fit in your GP9 and where did you install it?

 

Bob, I took your recommendation and used the T1-1925S. Cut off the end tabs and fixed it on some side plate "legs" behind the motor and above the drive. I 3M taped them to the sides of the Finescale 360 weights. It just fits but I had to shave the inside edges of the plastic frame/walkway piece that sits on the metal chassis slightly to get the body on.

Excuse the spaghetti wiring, still in test phase, honest... 

I am continually amazed and inspired by what you and your colleagues are doing on the A&O. Thank you!    

Sorry about the thread drift. 

Pete—which Maxxon motor and from where did you procure it?

riogrande491 posted:

Sorry about the thread drift. 

Pete—which Maxxon motor and from where did you procure it?

Bob, it's a Maxon RE 25, model # 118751.  I get them from The Motorman at micro-loco-motion.com   Used and surplus coreless motors of variety!

Same length as a Pittman 85xx but narrower at 25mm dia. Also the shafts have to be sleeved out from 3mm to ~4mm for Weaver/P&D drive. I've bought 4 so far, all work great.  The spec sheet is borderline for HO decoders, but I've tested with 25 x 1lb cars on level track to make sure I could get away with it. Probably about 1/4 of what you'll need to pull on the A&O mind you...  My locos are weighted to get to wheel-slip before stalling and I don't have any overload issues so far. I do mount the decoders on a brass sheet heat-sink with some CPU thermal goop. Not sure if that's really necessary but I'm a bit of a worrier...   

HTH

Here's how I fix them....

Mechanisms for Red Caboose GP-9s. P&D brass trucks and Des Plaines brass frames. As usual, Faulhaber gear head motors with everything turning 1:1 in ball bearings and wipers mounted in Delrin.

Decoder is LokSound. They are new to me but from my limited knowledge they seem really good.

One down, two to go. Two are P48, one is regular O Scale.

Wheels spinning and maximum voltage (13.5 volts) draws .22 amps.  My Pittman  gear heads can't do it, plus they won't fit.  The secret is very efficient gearhead motors

Looks like I need to touch up some paint.

You may see the first one a lot in the future.

Jay

Nice work Jay!  What's your overall gear ratio (motor to the wheels), and top speed running light at 13.5 volts?  Thanks!!

Hey Ted,

I was hoping nobody would ask!  Actually, I haven't figured it out yet.

The gear head motor is 14:1

The motor tower is 1:.82

The truck towers are 1.5:1

Top speed hasn't be computed yet.  I just knew this set of ratios gave nice slow to medium speed for switching or yard work.  Ball park 30 to 35 mph.

If the customer wants to speed things up a bit we just change the upper pulleys and belts of the truck towers.

Jay

Ted,

Overall works out to 17.2:1

Jay

Jay -

Can you post a photo or two of how you did the pickup wipers?

Thanks!

Bob S

Bob S,

The OC Cast/P&D truck is a real pain to install wipers.  I like to machine my wiper mounts out of black delrin.  I make them so, not only are the wipers removable, but so are the mounts.  I'll attach some photos I took the other day.  Hopefully, they'll help.

Jay

How you attach the acetyl blocks is obvious. Your photos are quite helpful for that. Not so obvious is the shape and mounting of the wipers to the acetyl, and if the wipers are shaped with tabs or other details, how they are made/procured.

Bob S

I buy them, a sheet at a time, from Rod Miller.  I'll try to add a link.

http://www.rodmiller.com/parts.html#wipers

Jay

Thanks! How are they attached to the Delrin? I don't see a hole for a #0 screw per Rod's directions.

You're kidding, right?

The examples in the photo aren't finished yet.  When drilled and tapped I use a 1.7mm screw.

Jay

Pete M posted:

riogrande491 posted:

As for the metal lathe I used, if you stick to P&D replacement parts you can do everything with just hand tools. I wanted to change the sprocket ratio for slower speed running. That helped when I used non-back EMF decoders. These days the motor control in the Loksound L is so good I won't change any more drives. The original drive ratio also produces less chain noise. 

Because acetyl shrinks over time, there have been outbreaks of cracked gears in many vendor's products, even in certain runs of HO locomotives. Over many years stuff happens.

Question for Pete - Which Tang Band speaker did you fit in your GP9 and where did you install it?

 

Bob, I took your recommendation and used the T1-1925S. Cut off the end tabs and fixed it on some side plate "legs" behind the motor and above the drive. I 3M taped them to the sides of the Finescale 360 weights. It just fits but I had to shave the inside edges of the plastic frame/walkway piece that sits on the metal chassis slightly to get the body on.

Excuse the spaghetti wiring, still in test phase, honest... 

I am continually amazed and inspired by what you and your colleagues are doing on the A&O. Thank you!    

Sorry for the thread drift and for attaching the photo with my post, but I'm hoping Pete will respond. I see you are using the machined aluminum frame from Kelly ? (IIRC) and wondered if you have discovered or decided on a way to attach the RC shell and sill to this frame?  I've got the same frame that Jay C. has done a wonderful job powering, but I haven't discovered a simply way to mount the RC shell/sill to it.

Have you gone this far with your GP?

Butch

Hey Butch,

Maybe you need to hire a better mechanic.  This Jay C. guy sounds highly suspicious.  Having said that, doesn't the shell just kind of snap in place.  They seem pretty tight, to me.

Jay

Jay C posted:

Hey Butch,

Maybe you need to hire a better mechanic.  This Jay C. guy sounds highly suspicious.  Having said that, doesn't the shell just kind of snap in place.  They seem pretty tight, to me.

Jay

Yeah, and I never cared for Jay C.'s music either.  Just not my style.

Oh wait.  That's Jay Z.

Nevermind.

up148 posted:  I've got the same frame that Jay C. has done a wonderful job powering, but I haven't discovered a simply way to mount the RC shell/sill to it.

Have you gone this far with your GP?

I've got Kelly's frame which Jay motored up with dual Faulhabers.  I've not finished out the body shell yet.  But in test fits, as Jay indicated, it just slips down onto the frame pretty snug.

...gregg

Hi All and you too Jay  ,

Yes, it's a fairly tight fit, but if you pick the loco up by the shell (I know, generally a no-no) it will pop right off in your hand and the frame, motor, trucks will drop out.  I'll look at it better tonight as I forget exactly how RC did it, but IIRC, the RC plastic sub-frame allowed a couple of screws to hold the shell, walkway and sub-frame together.

Kelly's frame replaces the RC sub-frame and the old type of installation is not possible, so we have to devise a new way of doing it.  I lost Kelly's email address so I can't ask him if he came up with a fix.

I just didn't want to re-invent the wheel if someone came up with a way to securely attach it together.

bh

Well Butch, maybe a couple wraps-o-duct tape otta doer.

Jay

If duct tape is too much you might try this, http://www.finescale360.com/

The RC shell was originally held in place by the coupler mounting screws on the ends, and a pair of hooks on each side of the motor mount that clamp over the deck. Don't file these off!

In the photo above we see an older, modified DesPlaines brass frame.

Bob S

Bob is right, the 4 tangs on the stock motor mount still hold on the middle of the body in my setup. But they engage with the plastic floor piece not the hood piece so once you have the loco weighted like this, do not try to pick it up by just the hood...  

Also the couplers still hold on the front and rear as long as you use the Red Caboose coupler boxes. Might need a small shim to get the coupler height dead-on the Kadee gauge depending which trucks you use e.g Weaver plastic, P&D GP or F Unit. I think there are actually 3 bolster height variants of the P&D brass trucks and only one gives the prototypical height for the GP9. I confess I'm not sure which one. Bob would know for sure!        

Sorry, I'm no help with coupler height. The milled aluminum frame may or may not be a different thickness at the coupler. I always measure and adjust when necessary.

The deck should ride at the same height above the rail head so long as the P&D acetyl bolsters are mounted to the top of the frame and there isn't too much weight on the frame. The only differences in ride height I've experienced with P&D trucks was caused by different axle bearing spring rates. Some trucks I have from ~2001 F-unit kits use very soft springs that bottomed-out when I initially over-weighted the locomotive. Other kits I purchased years later came with stiffer springs. 

As for picking up the engine by the shell, the tab arrangement may be stronger than you expect, at least until the deck at the tabs become worn. RC's 3-R models are considerably heavier than the 2-R. They have a steel chassis and a U-shaped steel weight under each drive shaft. Bill McClung told me that they are easy to convert from 3-R to 2-R.

All the best.

Bob S

Sorry Bob, I wasn't clear. The Finescale 360 frame does accommodate the RC coupler assembly properly. My coupler height comment was because I seem to have at least 2 heights of P&D (OCS) brass truck bolster on hand and I'm not sure which one is really right for the GP9. I do have some P&D F Unit brass trucks which I may have transposed. Needless to say, if I use the wrong one I get incorrect frame and coupler height.

I recall seeing a picture online of 3 (may have been 2) P&D brass truck bolsters of different heights. I thought it was on A&O or smugmug but perhaps it was from Jay C or someone else. Sorry for any confusion.

And my joke about lifting by the hood was because the body can come unglued from the floor due to the extra weight connected to the floor by the tangs on the motor mount, which work great as you say. But my glue joint from the plastic floor to the plastic hood came undone when I first tried to pick the more heavily weighted loco up by the hood. Lesson learned!

Again, sorry for any confusion. I was hoping to help anyone doing these conversions to avoid some of the (many) mistakes I've made along the way. That might be better achieved if I didn't talk in riddles...      

FWIW, the P&D truck bolster, meant for the RC GP-9, has the letters "GP" cast right in.  The only way to know for sure is to take the bolster off the truck (four screws), turn it over, and look.  The "F" unit bolster looks the same but is considerably taller.  If you use them on your GP it will sit way too high.

Jay

Thank you Jay, that explains it exactly. 

Thanks Pete, I try.  Just to continue flogging the horse, here is a photo that should help further with what I was attempting to describe.

[URL=http://s601.photobucket.com/user/jaycriswell/media/2015-03-08%20001%202015-03-07%20017_zpseo91fpxy.jpg.html][IMG]http://i601.photobucket.com/al...0017_zpseo91fpxy.jpg[/IMG][/URL]

Jay

Jay, the way I see it is that your approach is the ultimate after-market full-replacement drive upgrade, while Bob has refined the original Weaver/P&D chain drive setup to the leading edge of what's doable.  I've shamelessly copied both your ideas!

As well the Finescale 360 chassis is useable in both scenarios and has the benefit of ditch light wiring channels and machined-in side frames over the Des Plaines brass chassis. But it's lighter hence the supplied weights. Also Kelly's adjustable drive towers help in fine tuning the original chain drive. 

The only thing I would add to your most excellent solution is the Tang Band 1925S speaker module which I learned about from Bob's work on A&O locos. Not sure if you've tried that yet but from my experience it's a massive sound improvement over any of the regularly used "O scale speakers".   

Thanks for all that you do for O scale!