Weaver RS3 question

One of the best drives ever put in an O Scale engine IMHO.  The only thing you have to watch for is split tower gears.  The are easy to get from P&D Hobbies.  You will be pleased with the engine I think.

 

 

if you have any questions, give weaver models a call and ask to speak with gary.

 

www.weavermodels.com

 

 

I think also it is one of the best drives available.   

 

This is the original Weaver drive that came out in first RS3s.   Weaver also used it in the original FA-FB series and the original GP38s.  

 

At some point they changed over to the twin vertical motor drive.   I think that was done primarily to appeal more to the 3-rail market.   There is a theory that most 3-rail guys equate 2 motors with better quality and expect.  

 

I find ALL the two motor drives I have do run as smoothly as the single motor drives.   I have twin motor drives (in 2 rail) from 3 major manufacturers.

 

As for maintenance, sometimes axle gears split also.   But the neat thing is all the part are accessible and repairs are straight forward.   Once you take one apart, you will be an expert.   And parts are still available.   P&D hobbies is a good source.  

 

If you need to disassemble the trucks, use a small screwddriver and pry up slightly on the end of the pin inside the middle of the bolster on one side.   This snaps into place in the bolster.   If you pull from the truck side frame, you will probably break it.

PS:   If you buy a new RS3, FA, or FB from Weaver now, you will get the twin motor drive.

Hi Geoff,

 

The older Weaver chain drives run very well in my opinion. As other's here have mentioned, sometimes there can be problems related to cracked drive sprockets but replacements are available.  I just purchased two of the older GP38-2's within the last several months and I plan on purchasing several more. I purchased mine after asking several local long time O scalers about them. I like the way they crawl and they run very well with some of my Overland brass diesels.

 

One thing that I like about these drives is that you can change the drive ratio's by changing the sprocket sizes to achieve speeds more suitable to your liking. My plans are to use this type drive to 2 rail several Lionel GP30's and build several GP40's and 40-2's.

 

I don't think you'll be dissapointed with this drive, and the price is right too!

 

Travis

I have two of the older units and I replaced all the drive wheels with ones from NWSL most of the gears on mine split. The chain drive had the same problem. so I replaced it with NWSL gear reduction drive. they run pretty awesome now.

 

        Thanks for all the feedback. I saw one a couple of weeks ago at a swap meet

  for $125.00. I'm thinking now that I should have grabbed it! As for the issue of

  the gears splitting I'm curious if anyone knows what causes this. Does it help

  if you lube them really well or are the gears just not very good.

 

      Geoff

I think it had to do with the type of plastic they were using mine split just sitting in  the box.

the problem with splitting gears stems from the use of non-aged acetal plastic, that tends to shrink as it ages, getting too tight for the shaft and... rip!

 

these drives are quite versatile and easy to work on, as others have stated. some care should be taken when choosing replacement parts, as some have been known to be crudely cast, and cause binding in the chain.

 

on almost all of my Weaver chain drive engines, which numbers 4 RS and 3 FA units, I have converted them to twin tower drives. I dislike putting all the torque driving both trucks through one driveshaft, as I think it will eventually cause a part to fail under prolonged heavy use.

 

another item to be aware of, is the wheelsets bear in the acetal/delrin sideframes, which is fine for non-friction action, but since all the engine weight (and these units do need weight added) rests on the sideframes, the 'journals' will wear and elongate. the addition of bronze or brass 'hat' bushings will add long life to this critical component.

 

P&D Hobby Shop is an excellent source for parts, as is Sterling Instruments, which is where I've purchased sprockets and chain from. An interesting variation is the use of a larger lower sprocket for improved slow speed performance, very useful in a switcher unit. I've toyed with the idea of converting the sprocket-chain drive to a cog-belt drive using the same tower, since those parts are also available from Sterling.

 

finally, $125 is the top end that should be paid for a used single tower unit. That price should be for a new unit, or barely used. You can get servicable engines in the $75-$90 range, though auctions tend to drive up the price.

 

good luck.

I have several WEAVER locomotives representing the entire span of drive changes from the center drive gear to the, one and two vertical gear towers, and the current "China" drives. They will not operate together unless they have the same  generation of drive arrangements. The only problem I have had with the chain drives is that the chains tend to stretch over time and have to be shortened. Other than that they are durable locomotives. Other than the old Atlas F-9's they are probably responsible for quite a number of folks into O gauge because they were inexpensive! Mine just keep on going!

You can tell between the older "chain Drive" units from the Current Production "China Drive" by looking for the slit on the pilot steps of the diesel units. Older chain drive models do NOT have any "breaks" or Slits on the steps. the current production units do for Both two and Three rail. the two rail units have the pilots screwed to the body.

Jeoff

 

Your Weaver chain drive RS-3 is from an interesting period in the history of 2 Rail O.

 

Twenty years ago or so Weaver was just about it for a 2 rail O scale manufacturer with a line of locomotives and ready to run cars.  The other choices were plastic freight car kits like the old intermountain line or brass.  Older kits from Athearn or their successors were common on the second hand market and could still be purchased new in the box after 35 years or assembled with genuine 1950s brush marks.

 

A few people were fortunate enough to have the room required for mainline modeling.  That means 60 inch radius curves if you want to run brass O scale steam locomotives.  Many large brass locomotives won't pull well without modification and putting together a good looking car fleet of any size either took a lot of time to build from scratch or kits or a lot of money to buy brass.  That meant that in the world of O scale there were few layouts with large freight car fleets.

 

Most guys had smaller layouts.  Many of these layouts were switching layouts with no continuous running possibilities at all.  Freight car fleets tended to be very small and significant grades were uncommon.  Many people used HO power packs.  The combination of tight curves short trains, short distances traveled, an emphasis on switching and power supplies from a scale two sizes down helped to shape thinking about what sort of locomotive constituted good power.  B-B diesels handle tighter radius curves well. Good slow speed performance and low amperage draw were naturally seen as highly desirable attributes in a locomotive.  To further compensate for the light pulling locomotives and limited power supplies many freight cars were kept below the NMRA recommended weight.

 

Under those conditions, and with a remarkably high tolerance for mechanical failure as long as repairs were inexpensive, the Weaver chain drive locomotives were seen as an acceptable product.  That is attested to by the several positive responses that you have read here along with the caveats about parts breakage.

 

Since the early 1990s the O scale market has changed dramatically.  The large and lucrative 3 rail market developed an interest in O scale locomotives and cars.  MTH began marketing 2 rail locomotives and Atlas returned to O scale.  K-Line offered scale passenger cars and steam locomotives.  Lionel jumped on the scale bandwagon with some very nice scale freight cars.  The new scale freight cars from the major manufacturers were weighted to the NMRA recommendation or more.  With more high quality ready to run equipment available the car fleet on a layout tended to grow.  Sound and lighted passenger cars became more common.  Power demands grew and more and more layouts had something better than an HO power supply.  The housing boom gave more space for large layouts with continuous running at greater than yard speeds and often with mountain grades.  Realistic sound systems and realistic speeds on main lines made chain drive noise unacceptable.  Suddenly many O scale operators found them selves in a position to ask a lot more from their locomotives.  Chain drives faded as Weaver adapted to a changing market.

 

Your older Weaver locomotive might find a useful role on your layout.  Just don't ask it to do heavy haul mainline service and keep spare parts handy.  That would be prototypical for a 244 powered Alco. 

We are all products of our experience, and perhaps that is why I take exception to several of Mr Hikel’s comments.  Apparently the O scale community in the NW is different – several of his assertions don’t track with my observations of O scale in the east.

 

That means 60 inch radius curves if you want to run brass O scale steam locomotives.

 

 

I've attended most of the O scale National Conventions since converting in 1971 and have visited dozens of home layouts. A few had broad curves (generally for around the wall loop running), but those that were built in medium sized basements and were designed for operations opted for sharper curves. This was done to enable folding the route to take advantage of the middle of the room. John Armstrong, the recognized dean of model railroad planning advocated 54" curves for heavy mainline running. A significant number of the O scale home layouts in the east (20+ I can count near DC alone – my former layout included) had curves that size - and ran large O scale brass steam locomotives. The Canandaigua Southern had 54” curves.  Among the large brass locomotives John ran were a Max Gray B&O 2-8-8-4, Max Gray N&W 2-8-8-2, Overland B&O 2-10-2, Overland ex SP GS4 4-8-4, and a Westside ex PRR 4-4-6-4.  My first 4 O scale brass locomotives (USH PRR K4, L1, I1, and M1a) ran around 48” curves in my  “starter home” basement without modification. Articulated locomotives may need additional  trackside clearance for boiler overhang, but typically handle tight curves better than high driver Northerns.  Locomotives with 4 wheel trailing trucks may require narrowing the frame with a Dremel to allow for more trailing truck. In the case of the rigid wheelbase Q2 I filed the bearing block shoulders on the front and rear drivers for added lateral movement.  The important thing to note is that it doesn’t take a machinists skill or significant amounts of time to enable most brass locomotives to handle tighter curves. 

 

"Many large brass locomotives won't pull well without modification"   . 

 

 Back in the “dark ages” many locomotives indeed were shipped partially assembled with undersized bolt in weights.  Those wanting to haul longer trains up heavy grades (in my case 25+ cars up 3%) would either add lead around the factory weight or cast a new larger one – not rocket science.

 

"That meant that in the world of O scale there were few layouts with large freight car fleets"

 

There may have been few O scale layouts (relative to other scales), but lack of freight cars wasn’t an issue on the layouts I visited – space yes.  Guys with limited space often had a collection of cars (and kits) under the layout. Back in the pre-eBay days one could find a good selection of virgin affordable kits and older brass found on tables at O scale swap meets.  Finding time to build/paint them was the larger issue in building a roster on a modest budget.

 

 

"significant grades were uncommon" 

 

Don’t know what Mr. Hikel means by "significant grades", but layouts with 1.5 - 3% grades are common on O scale railroads in our area -  perhaps the John Armstrong influence to get more railroad in a given space.

 

"Many people used HO power packs" 

 

 I can’t recall a railroad on any O scale National Convention tours using an HO power pack other than on a test track. It seems most O scalers built their own in one form or another based on published articles.

 

 "Good slow speed performance and low amperage draw were naturally seen as highly desirable attributes in a locomotive"

 

My observation: For all but those that favor continuous loop running, good slow speed performance (especially smooth starting) is an essential feature for prototypical operation – not just on switching layouts.  Low amperage draw is the mark of an efficient design, is of value today (lets us use lower cost HO DCC decoders), and will be more so in the future with battery powered locomotives.

 

"To further compensate for the light pulling locomotives and limited power supplies many freight cars were kept below the NMRA recommended weight". 

 

 These were not factors O scalers I know worried about.  I put enough weight in my cars to achieve reliable tracking – 12-16 oz. – no more than necessary – none less.  The 16 oz NMRA standard for a 40’ freight car is slightly heavier than some cars on my railroad.  One factor that may have influenced the standard was that in the early days of O scale many trucks didn’t roll as well as those of today.

 

"Under those conditions, and with a remarkably high tolerance for mechanical failure as long as repairs were inexpensive, the Weaver chain drive locomotives were seen as an acceptable product. That is attested to by theseveral positive responses that you have read here along with the caveats about parts breakage." 

 

The failure rate of Weaver chain drives was a plastics manufacturing issue that should have been avoided – not an inherent weakness in drive train architecture. While I prefer the tooth belt drive like Sunset 3rd Rail’s, the chain drive will likely outlast the owner if you replace the Weaver axels and sprockets.  To further enhance the chain drive, check out Brian Scace (Sarge) posts on the MTJ forum. 

 

Bob Weaver designed his Alco chain drive diesels initially for O scale 2 rail, with a secondary objective of 3 rail.  I visited Bob’s 2 rail layout when he had the test bed chain drive chassis running on his layout for days on end.  To his regret he learned about his sub-contractor’s plastic molding problems only after selling hundreds of locomotives.  To his credit for years he provided free replacement parts. Weaver's move to the “China drive” (vertical motor mounted on cast truck block- multiple spur gears between drive wheels) was more a marketing decision than a manufacturing one.  Weaver could have (like P&D and NWSL) corrected the split gear problem by having his injection molding subcontractor improve the production process.  By adopting the dual integral motor/truck setup and using swiveling pilots the RS-3 could handle O-27 curves.  It also addressed the widely held 3 rail perception that 2 motors are better than 1.  I suspect this is in part  due to Lionel’s O  gauge line of diesels having two motors while their lower cost and weaker pulling O-27 diesels had only one.

 

Despite its shortcomings (the plastic frame limits added weight), Weaver Alco’s are still the most prototypically accurate non-brass RS-3 and FA2 produced to date. With an upgraded drive they are a cost effective alternative to brass models of the same prototypes.  Too much work - reserve a GGD FP7.

 

As Bob Turner would say – just my opinion

 

Ed Rappe

Ed, I agree with your comments. It is one of the best drives out there. The best part is it is very adaptable for scratch build projects. Ken the guy from AR

I got into "O" gauge 2-rail thru an Atlas BN set back in 1971 when I was in the Coast Guard. Most O gauge locomotive in use then were way out of my serviceman's price range. Later, when Bob Weaver brought out his early RS-3's, I picked one up and was delighted to find it scooted around those 24 inch radius curves with ease! I have been a 2-railer ever since! I was always of the opinion that the gear tower in the 2nd generation  Weaver would have befitted from a spring loaded idler pulley to keep a certain amount of tension on the chains!

 

Sure Ed, but you always seem to have a well informed opinion.

Mr. Rappe

 

Thanks for your lengthy response to my comments.  After reading them I'm not sure how different our observations really are.  Certainly we have had some different experiences and we may also have some different points of reference.  But there also seem to be some significant similarities in what we have observed in O scale model railroading.

 

One difference in observations certainly has to do with our respective geographic locations.  Homes with full basements are quite common in the east and relatively unusual on the west coast.  And that certainly has an impact on what type of layout someone builds or even what scale they choose with which to model.

 

Whether a layout is constructed with 48, 54 or 60 inch radius curves building an Armstrong style layout with a center peninsula is going to take 8 1/2, 9 1/2 or 10 1/2 feet of space to allow a single tack main line to make a 180 degree turn at the end of the peninsula.  Add in 4 to 6 feet for aisles on either side plus 4 to 6 more feet for benchwork on the outside walls and that means building such a layout in O scale in a space much under 16 to 20 feet wide is either not possible or puts such limits on the layout or the people in the layout room that it isn't very desirable.  On the east coast a 16-20 foot wide space is often available in a basement.  On the west coast that usually means giving up the use of a two car garage or a nice sized rec room.  Some large layouts, particularly out west, are in separate layout buildings because of the lack of availability of more traditional spaces.

 

On the east or west coast the total number of of O scale layouts of that size is relatively small. I am sure that in 40 years of O scale national conventions that you have seen dozens of wonderful large layouts.  But what percentage of the O scale market does that represens?  How many early diesels with chain drive mechanisms did Weaver sell to the owners of those national convention tour layouts and how many did Weaver sell to guys with smaller layouts that could only run shorter length trains?

 

I don't doubt for a moment that HO derived power packs were not seen on O scale nation tour layouts.  I certainly agree that home made DC power supplies have been common on large home or club O scale layouts.  But again, I think those tour layouts were above average not just in overall quality but in size and power demands as well.  Still, your reference to HO decoders is in a similar vein with my observation.  Whether it is a DC power pack, a DCC command station or DCC decoders, the use electrical or electronic components intended for the HO market by O scalers due to cost or the lack of availability of more suitable equipment has been pretty common over the years.  And I certainly believe that situation has contributed to many O scalers placing a greater emphasis than is seen in other scales on low current draw by locomotives.

 

You noted that "low amperage draw is the mark of an efficient design."  Allow me to ask you to revisit that notion and perhaps expand upon it.  Low amperage draw could be a mark of an efficient design.  But efficiency means getting a high percentage of work out of a mechanism for the power put into it.  Chain or belt drives are not high efficiency methods of power transmission.  That is why we haven't seen many chain drive airplanes since the Wright brothers.  If a Weaver chain drive locomotive is doing one watt of work how many watts must be put into it?  Is it really high efficiency or is it just low power?

 

Thinking from a manufactures perspective balancing manufacturing cost, retail price and market size it is my hunch that the low tooling cost associated with the chain drive was very attractive to Weaver.  In your conversations with Mr. Weaver did you ever talk about some of the business or production engineering side of the decisions made in developing the early diesels?

 

Our observations of car weights on O scale layouts is similar.  The weight you stated as your standard for reliable tracking, 12-16 oz, fits in with what I have seen and heard from most highly experienced O scalers.  But while an old intermountain 40 foot AAR box car might have fit into that weight category an Atlas AAR box car made from the same tooling weighs 20 ounces.  That puts them 33% above the NMRA recommended practice of 15 ounces for a 40 foot car.  The quality and variety of ready to run Atlas 2 rail equipment certainly seems to have added to the popularity of O scale but their inclination to build cars with diecast underframes or floors has produced many cars with weights over the NMRA RP.  Atlas USRA box cars weigh over 19 ounces, the little 70 ton covered hoppers weigh 23 ounces and the 50 foot PS-1 box cars tip my scale at 25 ounces.  Lionel has made some beautiful freight cars that are popular for conversion to 2 rail but some of those are quite heavy too, as much as 27 ounces for the Pac Car reefers.  The O scale passenger cars from K-line, Weaver, Sunset and Atlas have made prototypical length passenger trains much easier to obtain than in decades past.  More O scalers can afford such trains now compared to years ago.  But the heavy trains composed of recent rolling stock do require strong motive power.   

 

While the trains you see on O scale layouts in your home area or on national convention tour layouts may not have changed too much over the last 40 years can we agree that the O scale market has broadened since the 1990s? 

 

Can we agree that with the advent of a bunch of very good ready to run equipment it has become easier, taking less time or money or both, to acquire prototypical freight or passenger consists than it was years ago?

 

And can we agree that those cars tend to be heavier than they were in the past?

 

I came to O scale the same way many people now seem to have done it.  I started out with a 3 rail train set at Christmas. I modeled in HO in the 1980s.  I came back to 3 rail O in the 1990s and have moved into 2 and 3 rail O scale since 2000.  Many of the people that I know, whether they are younger or just newer to O scale seem to have followed a similar path.  While we might not be representative of the attendees at an O scale national convention I think we are a significant part of the market for new O scale trains since the 1990s.  I do think Weaver broadened their market appeal when then went to a more robust drive arrangement.  And that appeal was broadened in 2 rail as well as in the 3 rail segment of the market.  Fortunately, there do seem to be enough chain drive locomotives and aftermarket parts to continue to satisfy the demand.

 

Thanks for your thoughtful comments.  Even if we don't share the same conclusions it does seem that we do have had some similar experiences and observations. 

 

And please, do call me Ted. 

Geoff,

sorry for this late reply. I haven´t logged in here for a while. As some of our friends in this Hobby mentioned earlier, the Chain/Tower drives from Weaver have been in the older RS-3 and GP-38 models. I had a RS-3 and still own two D&RGW GP-38 which I bought second hand for a resonable price. On both engines one of the tower drives had split gears. But, this is a snap to repair!!

 

Straightforward job. Take it apart, clean out from old grease and identify what´s broken. Then get to P&D Hobbies and you get all the bits and pieces from these friendly folks - every part is available to get your engine running again. Fair priced, fast mailed.

 

The issue is as Ted mentioned, that the Cars have become heavier and the Weaver Engines can´t handle very much of them. I have a old P&D Hobbies F 7 in D&RGW livery which is a wonderful model with its brass trucks, fully sprung. But the pulling power is incredibly low, well... It sports the tower chain drive too!

 

Happy New Year to all!

Tom

 

 

Is it true that these older Weaver models with the chain drive like the RS-3 won't operate on Lionel tubular 0-31 curves?

Tom - The issue of pulling power with most of our Pittlman powered O scale diesels (and brass steam) is commonly wheel slip due to insufficient weight.  Those Pittman motors are rugged/powerful and can handle quite a bit of added weight.  On my road I weight road power so a single F unit can haul at least 12 1 pound cars up my 2.2% Horseshoe Curve grade (A-B-A with 36 cars).  With a metal floor in the P&D F-7 and space in the body you should be able to add enough lead weight to achieve the pull you want, while retaining some wheel slip overload protection for the motor.  My Weaver RS3's required a fair amount of work as I had to reinforce the plastic frame before adding the weight I was looking for. I recall we did about 4 or 5 RS3's in our group.  The approach was to fabricated a pair of 3/4" L shaped brass frame stiffeners that ran the full length inside the body. Lead weights were added above the floor between the stiffeners at each end.  After replacing those failing sprockets and axel gears we had some nice running power. 

 

Ed Rappe

Ed,

 

Do you have any pictures of your modifications? I have an RS-3 I would like to modify.

 

Chris

LVHR

Ed: Thank you so much for sharing your ideas. The P&D F7 has already some added weight (the pre-owner did glue in very big screws and nuts) but I should go for the metal floor plus added weight, I think. Usually I´m using lead. I´ll take this job on my "to do list" for the coming year. Thank you so much again for giving me this idea!!!

 

Cheers and Happy New Year!

Tom

 

    Thanks for all the info. My RS3 hasn't been run much yet since it is still in the

  painting stages. The tower gear will be new to me but I have a Red Caboose

  GP9 and 2 old Atlas/Roco F9's that all have split axle gears. So far I have just

  removed the split gears and am running with 1 less drive axle which isn't a 

  big deal on my small flat layout, but would be on a layout with grades. I will

  be contacting P&D about replacements. I'm surprised how many different 

  models have had the same problem. This must have been very frustrating

  for modelers buying these engines new. What obviously saves these engines

  is that they all look and run so nice.

 

         Geoff 

I have been a loyal user since they introduced their original RS-3 with the chain connected directly to the motor! An immediately howl went up saying they were to noisy! Weaver introduced the single gear tower kit, which I used on one of my locomotives. Then they went to the duel gear tower, which I also have. Then they went to the China drives. I have one of the China drive U-25's and and RS-3. All of these locomotive still run. Interestingly, they all double head well with the old Atlas F units.