Side rod wear

Sarah posted:

Dear community,

I'm coming up with a general question about side rod wear of  in O-scale. How likely is it that side rods become loose over a long period of time?

It has happened, but not all that common, in my experience and opinion. 

Yes, I know, the're meant to be lubricated but all the tractive energy is distributed via the side rods.

No different that the real steam locomotives, i.e. all the horse power is transmitted through the rods. Lubrication is the key in preventing EXCESSIVE wear. I thus a thicker grease on all the crankpins and rod bearings so that the grease is not thrown off during operation.

How about gearing the axles together at frame level?

Why bother? As previously pointed out, "If it ain't broke, don't f with it!"

Anybody done that?

Maybe buy I personally have never heard of that being done on a scale model of a steam locomotive, electric motor drive nor live steam.

Is that a stupid idea?

In my opinion,,,,,,YES!

Sarah

Valid concerns Sarah, but no need to worry, these things operate darn near a life time.

Actually, right after World War II, Walthers came out with steam locomotive kits using individually geared drivers.  As I recall, they called the system  "Poly Drive."   They were disasters. 

Thanks for taking away some of my fears. Just read model specifications on Mr. Kohs' website. The have all roller bearings on the side rods. Oh my god. 

What grease brand do you use? Getting thicker grease sounds like making sense. 

Sarah posted:

Thanks for taking away some of my fears. Just read model specifications on Mr. Kohs' website. The have all roller bearings on the side rods. Oh my god. 

What grease brand do you use? Getting thicker grease sounds like making sense. 

I use two products, 1) Red N' Tacky, and 2) a VERY thick grease (Lube-It SG2000) from Excelle Lubricants.

Don't forget the scale Lionel 0-6-0 - drivers geared together with spur gears cast right on the driver.

It is extremely rare to see side rods worn to the point where they must be re-bushed.  Early Max Gray used brass crankpins with brass rods, and the crankpins would go after a year or so of daily operation on museum track.  Easy to replace with steel.  

For most of us, a drop of oil on the pins and guides is enough.

I agree - gearing them together did no good, and tripled the drag.  Not at all efficient.

Sarah posted:

Dear community,

I'm coming up with a general question about side rod wear of  in O-scale. How likely is it that side rods become loose over a long period of time? Yes, I know, the're meant to be lubricated but all the tractive energy is distributed via the side rods. How about gearing the axles together at frame level? Anybody done that? Is that a stupid idea?

Sarah

The American Models S Scale 4-8-4, ESE 4-6-4 and 4-6-2's have all their drivers gear driven, the rods are just along for the ride.  They all run very smoothly.

It can be a little tricky to line everything back up if the drivers are removed for whatever reason, though.

Rusty

The Lionel US made Hudsons made in the 1990s had bronze bearing inserts in their siderods. Later Korean and Chinese siderods did not.

US siderods on the right:

Pete

There sure was a lot of Lionel post war steamers with all drivers gear driven.

Back about 1965 Model Railroader published an article on this subject based on their experiences with wear on O scale locomotives in use on a large commercial O scale display railroad that apparently ran their locos every day for several hours.  It may have been Minirama or Roadside America.  That is not important.  Their photos showed elliptical wear in side rod crankpin holes that occurred after many hours of operation.  They drilled and bushed the rods and repaired them.  I doubt if most of us will ever operate locomotives to that extent.  In forty plus years of building and working on O scale steam models I have never had to do this type of repair.  I would not let it worry me.

Joe

I have, but as Joe says, it only happens on Museum models.  Trivial to fix.

Recall a description of a FL (?) dentist who had an Overland UP 4-6-6-4 running on an overhead track in his dental office. He ran it for literally years and thousands of hours - and all of the model's components functioned perfectly !     Maybe someone can recall more details of this story ?

I have a Balboa On3 C-21 that has worn egg shaped holes in the siderods. It will definitely need to be drilled out and bushed properly, unless I can find a donor mechanism

All the Postwar and MPC Lionel locos I have seen had all drivers geared.     It seems to have been much more in the toy train market than in Scale.

Walthers Polydrive was one attempt to solve the quartering and rod wear "problem" without resorting to external spur gears that can pick up debris and detract from realism.  Also, the American Models Hudsons and Pacifics (offered circa 2000 in S-scale and S-gauge hi-rail) have their axles connected by spur gears hidden inside the frame.  Personally I think that's a good setup.  I wish they would have leveraged their experience and ventured into O!

Come to think of it, I've seen inside spur gears on some European prototype models, too.

Gear or siderod driven, both after extended use can have wear problems.  Wear is driven by the original design, manufacturing quality and maintenance.  I tend to buy good, but need some TLC, engines.   Some have had high run times.  I have a 226E engine that the axle bushings were worn enough to cause the gears to jam at times.  Lack of proper oiling is the main suspect for this one.   My pre-war gear driven B6 had loose idler pins.  In my opinion, they came loose from a design error.  Modern B6 remake had better pin mounting and I used them to repair.  I have a modern Lionel docksider that is siderod driven.  I don't know what happened with the previous owner,  but siderods were missing.   I got new ones and it runs OK, but tolerances seem a little loose. It wobbles a little.  My 1950, siderod driven 773 has significant run time, but runs very smooth.  Proper oiling only, no repairs.   A 1980's remake took many hours or fixing to get it to run smoothly.  Fundamentally the same design with different manufacturing quality.   

With proper oiling and maintenance, a good grade engine should last for decades, gear or siderod driven.

I haven't found this to be a problem even on my highest time steam engines. One axle on a steam locomotive model is driven directly. This causes the drivers on that axle to rotate and the locomotive to move. With the locomotive in motion, friction between the other drivers and the rails creates a torque that causes them to rotate, so the loads transmitted into the crankpins by the main connecting rods are less than if there were no contact with the rail.

As an example:

On your front-wheel-drive car, the front axles and wheels are powered and the rear wheels are not. What turns the rear wheels? The answer is friction between the tires and the road. No power provided to the rear wheels and certainly no connecting rods from the powered front wheels.

MELGAR

Lubrication...lubrication...lubrication.

I've got around two dozen modern scale steam locomotives that use the rods to transmit power to all the drivers. They all have at least 1000 scale miles and hours of operation. I can find no noticeable wear on the size rods. I use automotive synthetic differential oil (75W90 gear oil) on the rod bushings and crank pins. Heavy enough to not get slung off, light enough to not cause drag. I just fill a needle point applicator with extra from the garage.