Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

wheel play ?

687 views
9 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    July, 2009
  • From: somerset, nj
  • 1,878 posts
wheel play ?
Posted by gregc on Sunday, May 13, 2018 1:03 PM

had to replace some trucks.  Had some old metal trucks and replaced the brass and non-brass wheel with intermountain wheels.   The wheels can move quite a bit laterally between the truck frames.  Since the frames were metal, I was able to compress them in a vice a tighten them up.     And since the trucks are metal, don't want to use a truck tuner on them.

how much play should there be?   

what are the drawbacks of too much or too little play?

greg - Philadelphia & Reading / Reading

  • Member since
    February, 2002
  • From: Reading, PA
  • 24,273 posts
Posted by rrinker on Sunday, May 13, 2018 3:14 PM

 Don't have a hard and fast number, but there shouldn't be a whole lot of play. The car will wobble, the truck may run skewed and pick points or frogs easier.

 Problem here is almost certainly that the original wheelsets had longer axles. Best bet is to check Reboxx, their list is quite comprehensive and the actual manufactuer may be listed - but double check the old ones with calipers and go by your actual measurement. I know I had one upgraded and detailed former train set car that what they had listed in their chart for the exact make and model was way too wide. When I contacted them, they did note the error on their chart and it may be corrected now - that was 14 years ago. 

 Truck Tuner is definitely not designed for metal trucks. It may not damage the tool to use it on brass, especially if it's hardened (not sure if it is or not), but it would quickly chew through soft brass for sure. Plus, if the wheels already fit too loosely, the truck tuner wouldn't fix that.

                                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    September, 2014
  • From: 10,578’ (3,224 m)
  • 808 posts
Posted by jjdamnit on Sunday, May 13, 2018 3:15 PM

Hello all,

You need some play between the side frames and the wheel. The differential effect is still in play with our models. 

Too little play and derailments occur on curves and through the diverging side of turnouts.

Too much play and you run the risk of the wheels falling out of the trucks when lifted from the track and exaggerated bobbing from the cars.

This is a good reason to get an NMRA gage for the scale(s) you model.

According to my measurements; in HO, you should have about 1/32-inch (0.80 mm) of movement between the wheels and the side frames.

The easiest way to check is get a set of feeler gauges, slide the wheels to one side and check with the appropriate feeler gauge.

The distance between the inside of the wheel flanges need to be checked too.

If the wheels on the replacement sets are too close together this will appear to be excessive distance between the wheel and side frame.

Also the axle length has a factor. If the axles are too short; even with the wheels in gage, there will be excessive space between the wheel and side frame.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    January, 2009
  • From: Maryland
  • 7,073 posts
Posted by ATLANTIC CENTRAL on Sunday, May 13, 2018 4:01 PM

gregc

had to replace some trucks.  Had some old metal trucks and replaced the brass and non-brass wheel with intermountain wheels.   The wheels can move quite a bit laterally between the truck frames.  Since the frames were metal, I was able to compress them in a vice a tighten them up.     And since the trucks are metal, don't want to use a truck tuner on them.

how much play should there be?   

what are the drawbacks of too much or too little play?

 

Are these trucks sprung? Sprung trucks require a little more play than rigid side frame trucks. As much as 1/16" is usually OK.

Don't go by the REBOXX recomendations for Kadee sprung trucks, they are wrong.

And know that REBOXX only sells semi scale code 88 wheels.

There are other wheelsets out there with different length axles if Intermountain are too short.

Sheldon

    

  • Member since
    November, 2016
  • 238 posts
Posted by j. c. on Sunday, May 13, 2018 4:18 PM

not a fan of replacing wheel sets if i have a problem with a truck i replace the truck , i did replace wheel sets that were too long for the truck frames resulting in cars that had were worse rolling than the start as the frames pinched the axles  acting like a brake.

  • Member since
    September, 2003
  • 5,593 posts
Posted by Overmod on Thursday, May 17, 2018 3:17 AM

ATLANTIC CENTRAL
Are these trucks sprung?

Is there any possibility he'd be adjusting endshake in sprung trucks by compressing something in a vise???

As in the prototype, you'd be using some kind of shim to adjust the positions of the sideframes relative to the bolster to control the distance between bearings.  These might have to be very thin (or filed after installation to be very thin).  Alternatively he could bore out the existing holes and fit plugs, perhaps of better bearing material like Delrin, and then use the truck tuner on those plugs to get the right surface finish and internal taper.  I suspect few would notice if the 'back side' of such plugs is longer than prototype hub liners or cartridges, to suit shorter axles.

  • Member since
    July, 2009
  • From: somerset, nj
  • 1,878 posts
Posted by gregc on Thursday, May 17, 2018 4:52 PM

the replacement truck are not sprung.

i measured ~r0.02" of play.   I don't think 1/50" is a lot of play, but it feels like a lot.

greg - Philadelphia & Reading / Reading

  • Member since
    October, 2001
  • From: OH
  • 16,257 posts
Posted by BRAKIE on Friday, May 18, 2018 6:05 AM

My policy is "If its not broken then let it be"..I do not look for things to worry about as long as the car is giving me derailment free operation.

Now if a car becomes a problem child and can't be fixed then I simply replace the faulty truck or use a new wheelset.

Larry

SSRy

Conductor

  • Member since
    July, 2009
  • From: somerset, nj
  • 1,878 posts
Posted by gregc on Friday, May 18, 2018 9:59 AM

i purchased a car from ebay.   Built by Revell (?).  it had plastic wheels.  I broke one truck trying to remove the wheels.  The wheel was shouldered.   So i needed to replace the truck because one was broke and the other had plastic wheels.   I had the spare trucks and tried using them

greg - Philadelphia & Reading / Reading

  • Member since
    July, 2009
  • From: somerset, nj
  • 1,878 posts
Posted by gregc on Saturday, May 19, 2018 2:59 PM

i built an adjustable ramp with a 1/4-20 screw I could turn by hand.   I measured the grade on a bunch of my cars by counting the number of turns.   (7 turns with a 36" length is ~1%)

the best car rolled with 0.5% grade.  an accurail boxcar.   Most accurail cars were < 1.5%.

one car seemed to have problems > 3% (don't know the manufacturer).  I had replaced plastic wheels with proto 2000 wheels years ago.   the truck tuner and some teflon lubricant didn't seem to help.   Replacing the proto wheels with intermountain made a big difference (1.75%).   The proto wheels had some play.   the intermountain wheels are about 0.015" shorter.   ended up with 0.04" of play.   I think the taper angle may be different on the wheels.

is it the play or taper?

i re-examined the car with the replacement trucks.   They didn't roll until the grade was > 2%.  when I remeasured the play, it was more like 0.035".  So I tried to compresss the trucks to reduce the play.   when I reduced it to 0.02" on both trucks, it rolled with about 1% grade.

based on this, it seems more than 0.02", 1/50" of play is not good.

my worst car is a walthers bax car car that didn't roll until the grade is 2.4%.  The truck tuner and some lub helped, so that it roll on a < 2% grade.

?

greg - Philadelphia & Reading / Reading

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!