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Good Evening Group.  I have posted another topic regarding trying to obtain the article on rebuilding a Red Caboose GP9.  A comment was made, and it appears from searching the internet that the P&D replacement drives have issues with the gears and the bonnet (hoop stress), hence this post.  Before I dive into this project a couple of questions:

a)  Has P&D solved the problem or should I order extras parts from them or replacement parts from another supplier?  If so what parts and which supplier?

b)  Without the use of a metal turning lathe, is the repair/replacement of these parts within my capability?

c)  Is the Finescale 360 retrofit a better option?

Thanks,

Stephen Wilson

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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.

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!   

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

Last edited by big train

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 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.

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!    

2016-10-08 20.55.07

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Last edited by Pete M
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

Last edited by Pete M

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.

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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

 

 

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Last edited by Jay C

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

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!    

2016-10-08 20.55.07

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

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

 

Last edited by up148

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

Last edited by riogrande491

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...      

Last edited by Pete M

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

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!          

Last edited by Pete M

"Well Butch, maybe a couple wraps-o-duct tape otta doer."  Yeah Jay, good ole duct tape will solve most problems in the world.

Thanks for posting Kelly's Finescale 360 contact info Jay, as I can contact him if I have any questions. He really brought that custom frame idea along.  The RC GP-9 has never had it better. From Des Plaines brass frames of a few decades ago to the Finescale 360 set up now.  Wow!

Wouldn't trade my Jay C drive for anything, but at least there are options out there now that really improve this most venerable O scale model and without having to possess machining skill sets and equipment.

Great Thread!!

 

Butch

 

 

Last edited by up148

Jay -

I don't know what "machined-in side frames" means either. Maybe ask Pete?

Anyway, I learned something new about the two different P&D bolsters. I never worked on both an F and a GP at the same time so I didn't have a chance to mix them up.

I do want to encourage you to at least download the TB 1925 and TB 2008 module data sheets from Parts Express and look at the dimensional drawings to see if either one would fit in your installs. TB modules sound so much cleaner and deeper than even 2" high-bass speakers I've installed in the past. FYI you can cut off the mounting tabs without letting the air out.

Bob S

Last edited by riogrande491

Jay, there's what's described on Kelly's site as "Prototype frame detail machined into the underside of the frame" which makes it deeper than the Des Plaines brass plate. I'm not sure its exactly prototypical side-frame depth, but it helps to fill the gap where the real  thing would have the side frames visible, especially if you're modelling a later GP9 with cut away side skirts. I seem to recall that the first batch didn't have that (or the ditch light wire channels) but don't quote me as I only have the later versions myself.     

Pete,

Once again, thanks for the feedback.  From what I've seen Kelly's frame has some rather shallow relief machined into the top and bottom of his frame.  Nothing of any significance and hardly noticeable once the gussets, fuel & air tank are installed and the whole thing painted.  Once detailed, I doubt many could tell the difference.  Again, don't get me wrong Kelly's a good guy and filled a need but I'll take the brass any day over aluminum.

Jay

riogrande491 posted:

Jay -

I don't know what "machined-in side frames" means either. Maybe ask Pete?

Anyway, I learned something new about the two different P&D bolsters. I never worked on both an F and a GP at the same time so I didn't have a chance to mix them up.

I do want to encourage you to at least download the TB 1925 and TB 2008 module data sheets from Parts Express and look at the dimensional drawings to see if either one would fit in your installs. TB modules sound so much cleaner and deeper than even 2" high-bass speakers I've installed in the past. FYI you can cut off the mounting tabs without letting the air out.

Bob S

Now I know why I ended up with a "low-rider" F Unit and an "off-roader" GP9 when I did two upgrades at once...  

Bob, those speakers have changed my life!  I have the 1925S in everything now, even my Yoder 44 tonner (bit of a squeeze).  I never get tired of sound during ops sessions like I used to. And the HO guys that come to my ops sessions can't seem to stop grinning either.        

Jay C posted:

Pete,

Once again, thanks for the feedback.  From what I've seen Kelly's frame has some rather shallow relief machined into the top and bottom of his frame.  Nothing of any significance and hardly noticeable once the gussets, fuel & air tank are installed and the whole thing painted.  Once detailed, I doubt many could tell the difference.  Again, don't get me wrong Kelly's a good guy and filled a need but I'll take the brass any day over aluminum.

Jay

All good. I added Evergreen I-beam side-frame sections to the brass ones I had from before and it looks great anyway. I started to add traction motor cables etc. that are visible when the side skirts are cut away on the CP GP9u upgrades, but that is a quick way to lose one's sanity...    

Pete M posted:

Now I know why I ended up with a "low-rider" F Unit and an "off-roader" GP9 when I did two upgrades at once...  

Yup,  just figured out a couple of days ago when individual Sunset F units in ABBA sets ended up having different ride heights.  With the GP trucks I was having to add almost 3/32" of spacers to make them match with this constant WTF going through my head.  I guess in one of my last orders I must have added GP trucks to the cart for some reason, I be clueless.   Now to see about either exchanging them or selling them and buying the F unit version.  Pfffft!

"Butch, as you know, I've done some with Kelly's frames and they are nice but the DesPlaines are heavier and cheaper.  What am I not seeing here?"

Sorry, I can't find the quote icon so I'm doing it the old fashion way.  

I still have two Des Plaines brass frames Jay, but liked the fact that Kelly's frame was stiffer. One of my DP frames has a bow and I figured it would change the shape of the plastic RC walkway rather than the walkway straightening up the DP frame. I also figured it might not be as stout as Kelly's frame going forward, which is mostly likely wrong. Actually both frames will work fine, but I wanted to try Kelly's frame and help his project to fruition. 

I checked the fit of the RC loco on Kelly's frame last night and I was totally wrong. Couplers will hold his frame to the walkway/shell very nicely, just like they do on the factory set-up.  Very easy to do this.    I'm not sure what I was thinking, but I'll chalk it up to a senior moment.  

I have enough decorated RC shell kits, purchased decades ago, that I can use the DP frames to make un-powered units. I won't need more than one powered unit per train on any layout I'll have in the future. 

This thread has re-inspired me to get my a-- in gear and back on these projects. I love GP-9's almost as much as "F" units and have enough of each in the queue to take years to complete if I just get started. 

 

Butch

 

 

Butch,

A long time ago you said, "I still have two Des Plaines brass frames Jay, but liked the fact that Kelly's frame was stiffer.".  I don't really agree.  I much prefer brass and I hate aluminum.  Plenty stiff, especially after I solder on a pair of these.   In fairness to Kelley, I got the idea from him when he gave instructions for doing them in plastic.

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Pete -

Call me crazy but I'm about to try hanging a TB1931S module under a DP GP9 brass frame, through the fuel and air tanks, firing down. To distract the viewer's eyes the trucks will be silver but the rest black. Look over here, not under there...

What got me started? I've been editing a new sound file for a pair of New River & Western GP9s to run on the A&O. (In theory the NR&W is now a wholly-owned subsidiary of the A&O.) They will be initially operated using a ProtoThrottle (I hope there will be enough cab bus bandwidth to do that with 18 NCE throttles running during full-on op sessions.) The test speaker on my LokProgrammer is currently a 1931 and I just can't go back to install a smaller module.

There should still be room in the fuel tank for some cast-in-place low temp alloy weights.

Last edited by riogrande491

The model is packed away, but it looks exactly as it did when you finished with it.  I'm really talking out of school here, as I don't remember what Kelly's instructions were, but do remember at one time I was going to removed these vertical (under chassis) braces from the stock RC chassis and attach them to either the DP or Kelly's aluminum chassis. This could have been thinking from 20 years ago as this has been a long term project.

What is the proper set-up, I can't remember now?

I know that feeling Bob!

I got hooked on TB 1931s a couple of years back as well. And yes, I too have one on my LokProgrammer board.   The 1925s that I used to think were the bee's knees sound a bit lame after that.  I have TB1931s in my Atlas MP15DCs and C-424, OMI MP15AC, C&LS RS-11s and 32s.  My P&D F7A and B have TB1942s now. The chassis are basically a speaker with a truck on each end, thanks to the space created by using Jay's dual-motor drives. 

Somewhat ironically the only locos I haven't been able to cram 1931s into are my RC GPs so I am very keen to see how your cunning plan works out! 

Pete

Pete -

When the time comes I'll post progress photos of the fiasco, er, build on the A&O web site. It would be relatively easy to hide a 1925S in the fuel tank since it is almost exactly the same length. The S0768 16-567 engine very rapidly drops to idle and has a good, throaty sound that just demands more bass. The file reminds me of a screaming Ontario Northland GP9 kicking cars posted to Youtube.

Trouble brewing

Here you can see the relative size of a 1931 compared to the under frame of an original RC 2R drive. No, I won't be modifying this one for the project. Of course the usual weight in the fuel tank will have to go, but there will be room in the sides of the tank for Cerrobend. I also have U-shape steel weights for 3R locomotives that Bill McClung gave me some years ago. The fake RC plastic frame stiffeners aren't the right profile (should be more of an I-beam) so I'll do a little faking there, and move them outboard to clear the speaker. How do I know? I photographed GW2233, an ex-ATSF GP7, while being scrapped (with permission, of course.)

In my narrow hood Overland diesels I still install the 1925S. Nobody has ever complained about the sound.

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