Evening
I've never worried about it, or ever had a problem. If one is running a bit faster than the other, its wheels are going to spin on the rails some, enabling the other locomotive to skid a bit.
Sure, it probably is working a little harder, while helping the other locomotive work less. But as long as you don't run them for countless hours on end, it would be highly unlikely you'll overheat it and burn it up.
Steel on steel friction is more, but similar to a marble on glass. Yes, it is working a bit harder, but not that much harder.
Will the wheels wear more on that locomotive? Of course, but most of us won't live long enough to see enough of a difference
When all is said and done, that faster locomotive spinning its wheels a bit, will probably spit polish your rails good, greatly minimizing your track cleaning labor
TF
I have never witnessed a burned out motor due to lack of speed matching, but have heard a fair number of spinning lokey wheels due to two lokeys not properly speed matched. I reckon the worst of that is how tough it may be on a wheelset due to constantly spinning.
I have also run HO scale for 60 years, and before that I ran O guage for 10 or 15 years. What a long strange trip it's been, huh?
When I started in HO, everything was DC, and I was a poverty-stricken teen, so my roster was a mismatched collection of diesels and steam. With a couple of small loops and a bunch of random rolling stock, I wasn't running long trains, so I seldom even ran double headed locomotives.
Now, I frequently do. I speed match when I can, which is pretty easy. But, I've never burned out a motor, except one subway motor which was never MU'd except to pull the CMX machine through my very low tunnels for track cleaning, where no other engines would even fit. That was only once every few months.
I snapped a lot of Athearn rubber bands on belt drive engines, though. Does that count?
It takes an iron man to play with a toy iron horse.
I've never heard of or experienced motors burning out, or gears being damaged, due to speed mismatches. The only thing I've heard suggested is to put the faster locomotive in the lead. If the faster locomotive is trailing, it will be basically handling the entire load of the train by itself while pushing the lead locomotive.
I have two Athearn BB SW1500's (later run with the correct body style) purchased on the same day, and when I recently put them on the track, they ran at different speeds. Oh well.
PRR8259One starts moving at speed step 1 of 28 and one starts moving at speed step 2 of 28. Adjusting Vmin did not help. When attempting to run my son's two units together there was significant wheelspin on both starting and stopping. Again, CV changes did NOT help.
I find sometimes adjusting CVs 3 and 4 can help, delaying the time that the one that wants to start first actually starts moving.
I also find using Decoder Pro to check the speed curves can help. I've found situations where I thought an engine was set to a straight-line speed 'curve', but in fact one of the steps was set too high or too low for some reason.
Yes, I agree starting voltage is most important to prevent one unit from experiencing wheelspin.
Yes, in plain dc operation one can be fortunate enough to get certain locos to run together that aren't the exact same model and product run. It seems that some Athearn engines have similar gearing to some Bowser and some Atlas engines, and in plain dc I have been able to run mixed consists of some of those locos. I just have not done that long term (after multiple gear failures in large scale). Walthers Proto units have odd gear ratios and are less likely to pair up with an Athearn, Bowser, or Atlas unit.
As Sheldon well knows, my layout is composed of Kato sectional track mostly glued down (to non-movement of joints) with Liquid Nails. Although I used as many of the longest track sections Kato sells in HO Unitrack, I still have more joints than the average layout where Atlas or similar flextrack might be used. A few uneven joints have been polished with an oil stone to smooth them out. However, more joints equals more opportunities for wheel wear. I do not know how much more wheel wear we have here than others (most in this hobby accumulate trains for the layout they hope to have and so are not running them daily as we do here).
As I alluded to above, gear failures are much more common in large scale where the forces acting on the model gearbox are tremendously greater than what we have in HO (volume and weight can be 27 times that of HO), but I have run a handful of HO locos long enough to wear out their motor or gears, after for example several sets of brushes in a Mantua Tyco unit the motor eventually got very weak and it was retired. One other was the 1970's Model Power Sharknose, which lasted through 3 can motors before the gears got bad and it was retired.
As a kid I used to run 200 laps of the layout with the Model Power Sharknose at full speed with a 4 car passenger train. That would be about 267 scale miles at one time, and I did do that an awful lot, so that would be very hard on can motor and gears. (We did keep things lubricated). That is how you wear out can motors in a Sharknose.
Also, I had an early 2000's Genesis F unit that the more I ran it the worse the gears got and it would not run with other similar Genesis F units. I couldn't take it any more and made it into a dummy unit--but the gears were definitely going at the time I converted it over to a dummy.
After becoming an adult and playing with brass trains on a friend's layout that had 48" minimum radius curves, and we still had accidents where brass cabooses hit the floor and were seriously damaged, etc. I did become much more careful of how I treat locomotives. Regardless of the money involved, they are no longer cheap throw away toys like the old Tyco stuff, so we try to treat them with respect to extend the life as long as possible.
People who run museum layouts will tell you that the better grade diesels today typically will run for 1000 hours (guy who often posted on the Atlas forum said that). Most people aren't going to log 1000 hours on any one loco. Howard Zane reports running a PFM United 2-8-0 or 2-8-2 (I forget which) for much of one year, 8 hours a day, 6 days a week on his once upon a time store layout--and it still ran fine after all that time. Also it depends HOW the loco is run. Some of us run trains slowly which inherently places less stress on the gearboxes. Others of us run fast. I have also owned brass steam locos that had so much run time on them (by others before me) that the rods were beginning to wear through in places.
Proper lubrication, but not over-lubrication, is wise.
Well, I had a nice reply to this thread back on Friday - when the forum broke.....
My experiance seems to be similar to the OP. I have never burned up a motor or broke a gear in ANY HO locomotive.
I run DC, and while I have a good amount of experiance operating DCC, I zero experiance with speed matching, CV adjustments, etc.
So I will restrict my comments to my own DC experiances over the last 56 years.
Diesels - I do run mostly MU lashups of the same or very similar locomotive drives. I model the early 50's, when railroads were still running most diesels as matched sets.
But I surely don't worry about what production run, I don't modify locos to match speeds. Never any issues. And I have successfully mixed brands and types on multiple occasions.
I run long trains, trains that often NEED two or three powered units to handle my 2% grades easily - 40 to 60 cars, sometimes more.
I have found that the most important issue is not speed, it is starting voltage. As long as the starting voltage is close, they all seem to run just fine together.
My diesel lashups are anywhere from two units up to four or five units at times. We are talking 1st generation diesels, EMD E & F units, ALCO FA & PA units, GP7's, RS3's, etc.
Locomotive brands include Proto2000 (mostly LifeLike era), Intermountain, Genesis, Athearn (heavily reworked Blue Box), and a few others.
Sure, there are some locos geared so dramaticly different that running them together is simply not a good idea.
Steam locomotives - I doublehead lots of steam, in fact most of my steam powered trains are double or even triple headed. Many are matched pairs/sets, many are not.
Example - Proto2000 2-8-8-2 (converted to 2-8-8-0 on my layout) and Bachmann Spectrum 2-6-6-2 - they run great together.
Wheel plating wear - well plating does sometimes wear off. I guess the factors are different for everyone.
I have limited fleet of BLI steam - have not run them enough to see any plating failures.
On the other hand I have lots of Bachmann, mostly Spectrum, steam - I can see some "wear" on some wheels, none are "worn off".
I wonder what factors effect plating wear? Speed? Brand or type of track? Cleaning methods? sharp curves?
I would think sharp curves would be a big factor on steam locos? My mainlines have been 36" and above for a long time now.
I don't know, but it has not been an issue for me.
As I said in the beginning, I have no practical experiance speed matching DCC locos. BUT, I hear these stories, read these posts, where otherwise identical locos will not run at the same speed despite the same CV settings. Or they will not run the same because of different brand/series/vintage decoders?
Since what I do, and have been doing for 50 years, is working fine, speed matching DCC locos is a task and a problem I am happy to not have.
As four GP7's roll by with a 50 car train.......
Sheldon
I absolutely do not run anything that isn't correctly speed matched either in plain dc or in dcc.
In plain dc I usually only run locos together that are from the exact same model and production run.
In dcc I generally do the same because speed matching is not always perfect, and I have seen last year's production Scaletrains ESU Loksound 5 equipped Tier 4 Gevo fight this year's latest run of the same thing. One starts moving at speed step 1 of 28 and one starts moving at speed step 2 of 28. Adjusting Vmin did not help. When attempting to run my son's two units together there was significant wheelspin on both starting and stopping. Again, CV changes did NOT help.
We run long heavy trains of 40 to 60 or more cars in HO including big autoracks and heavy 86' Tangent autoparts boxcars that greatly exceed the 4 ounces. Any wheelspin is not tolerated period. We only use matched sets of Scaletrains Gevos or Genesis 2.0 SD70ACe locos.
If you have wheelspin my real world experience is that you get excessive plating wear. Bare brass wheelsets will never conduct electricity as well as the nickel plating does. We want to retain the nickel plating as long as possible.
I have owned many BLI steam locos whose wheel plating was gone in 10 to 20 hours with even short trains. They never pickup power as well once the plating is gone.
Also wheelspin leads to broken gears especially in large scale. I have personally seen the gear failures on my outdoor layout (both Aristocraft steam and the LGB USRA mikados, which unfortunately ate gearboxes up and destroyed LGB's reputation. Aristocraft improved their gearboxes relatively quickly; LGB did not).
If I see anything close to wheelslip I either add units or immediately shorten the train. Because I have good ears (musician) I have learned to listen for wheelslip and then react accordingly
John
It's probably safe to run in pairs two locomotives of the same type and manufacturer, although I have seen some run at different speeds. DCC allows me to speed match two locos of different types, in most cases. If not, could it hurt the motor? If running many hours, long trains and in slopes, I think it would. I have seen motors burn out, but can't make a direct connection with MU operations. I run steam, including some old brass engines, and I would worry about wheel/plating wear.
Simon
I've never heard of burning out motors with mismatched DC locomotives. One would just be pushed or dragged.
I got into HO 60 years ago. It has always been said that speed matching was necessary to prevent motor burn up. I owned some junky Varney and Tyco engines and others over the years. I have never speed matched engines and never replaced a motor. I have come to the conclusion that lack of speed matching does not harm engines. It certainly makes them start and run smoother. So I would like some feedback if anyone has burned up an engine when double heading. It is time to put this old wives tale to bed if not true.