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Wheels, what size to use?

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  • Member since
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  • From: Austin, Texas
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Posted by jasperofzeal on Monday, April 23, 2018 3:17 PM

riogrande5761
 
jasperofzeal
 
Don't worry about capy or prototype wheel stuff (unless that's what you want).

 

For beginners that may be ok.  The size is more noticable for cars like tank cars or hi-hip covered hoppers where you can see the wheels are alot more exposed visually.  YMMV

 

 

Truth be told, I do try to use correct wheel sizes and put 36" where they belong (tanks, hoppers, intermodal, etc.).  I just tried to keep it simple for the OP since it appeared to me that he wasn't splitting hairs about wheel size and was just wanting to use 33" for all his stuff.

TONY

"If we never take the time, how can we ever have the time." - Merovingian (Matrix Reloaded)

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Posted by NWP SWP on Monday, April 23, 2018 3:41 PM

Right now I'm just trying to get my cars rolling at the club, with time proto correct wheels, couplers, trucks, and NMRA proper weighting will be added, (not saying my cars aren't weighted but they're just stock weighted.) perhaps I'll even equip my cars with RFID chips to aid tracking on my own railroad.

I'm just trying to take a step in the right direction.

Steve

If everything seems under control, you're not going fast enough!

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Posted by dmikee on Thursday, April 26, 2018 1:51 PM
I made the mistake of buying a whole box of 36" metal wheels to replace 33" plastic wheels on my NYC passenger fleet. Major problem: the increased diameter made the new wheels rub against the false brake shoes on each car. Nuts! Size matters.
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Posted by kasskaboose on Thursday, April 26, 2018 7:37 PM

Is mixing wheel set size a problem?  Given the 40-year AAR rule on freight cars, I'd think that there are a mx of different wheel sizes on layouts.  Do you check the coupler height whenever the cars are together of different wheel sizes?

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Posted by Reynold on Thursday, April 26, 2018 9:05 PM
A ton is 2000 pounds. So cars of 200 000 LB CAPY are 100 TON cars. Cars of around 100000 LB CAPY are usually on trucks with 5' 6" wheelbase and 33" wheels. Cars of around 140000 LB CAPY are usually on trucks with 5' 8" wheelbase and 33" wheels. Cars of around 200000 LB CAPY are usually on trucks with 5' 10" wheelbase and 36" wheels. The newest cars are now often 125 TONS Cars of around 250000 LB CAPY are usually on trucks with 6' wheelbase and 38" wheels.
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Posted by rckingsnorth on Friday, April 27, 2018 3:52 PM

Wheels, what size to use???

When replacing wheel sets, axle length can be important.

Intermountain is 1.002" long (all lengths are +/-)

Bachmann is 1.012"

Kadee is 1.017"

Bowser is 1.025"

Excessive endplay (length too short) will cause the car to sit lower and tilt from side to side.  Too long, and the wheels bind.

The old Athearn blue box trucks used 1.040".  The Kadee 1.017" seem to work OK, perhaps because of the rounded axle ends.

You will find significant variations in a single manufacture's trucks, probably based on the China source.  I test the supplied wheel set for end play, and then test different replacements for best fit.

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Posted by Anonymous on Friday, April 27, 2018 5:44 PM

rckingsnorth

Wheels, what size to use???

When replacing wheel sets, axle length can be important.

Intermountain is 1.002" long (all lengths are +/-)

Bachmann is 1.012"

Kadee is 1.017"

Bowser is 1.025"

Excessive endplay (length too short) will cause the car to sit lower and tilt from side to side.  Too long, and the wheels bind.

The old Athearn blue box trucks used 1.040".  The Kadee 1.017" seem to work OK, perhaps because of the rounded axle ends.

You will find significant variations in a single manufacture's trucks, probably based on the China source.  I test the supplied wheel set for end play, and then test different replacements for best fit.

 

This is a very good point to make. 

I recently bought a whole bunch of code 88 Intermountain Wheelsets (they were on sale) to replace the code 110s on some cars.  Ive discovered that they dont fit on Atlas cars, so I will need to find another source (NWSL has different axle lengths I belive).

From my memory, I did not have any trouble installing Intermountain wheelsets in Accurail cars.

Anywho, for resistor wheelsets, you will need to discuss that with your club.  They likely have an exact standard stating the resistor value and part number required to achieve occupancy detection.   

Generally speaking you will want in the ball park of 5k-10k ohms of per car to acheive single car detection (depending on the type of block detector and wiring configuration).  Again this is a question for the club.   If they specify two resistors per car, then put two resistors per car.   

I can tell you that I know a guy who did two 20kohm resistors per car and a single car did not trip the circuit (not sure what detectors he was using).   It took him 1.5 cars (or three trucks/3 resistors) to get occupancy.  Two 20kohm resistors on one car equals 10kohms of resistance per car.   

I will likely use around 15kohm on 2 trucks.  Im preping for this by only painting the outer axels on the cars, leaving the inner sets bare metal on the back and axel.

If your club is requiring you to install resistors on cars, they should have a set method for doing so and someone should be able to teach you.

 

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Posted by NWP SWP on Thursday, May 10, 2018 10:58 PM

Checked with the club, according to the rolling stock master he says use 0805 resistors with (I am not completely sure of this) 15kohms of resistance, another thing are 33" wheels suitable for streamlined passenger cars?

Steve

If everything seems under control, you're not going fast enough!

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Posted by NHTX on Friday, May 11, 2018 9:13 AM

      Searching the 1956 and 1961 Car Builders Cyclopedias, all streamlined passenger cars rode on 36 inch wheels.  This holds true for passenger cars from the heavyweight era as well.  Remember, these heavyweight cars wore this title because vehicles in the 80-90 ton range were the norm, especially sleepers and diners.  The heavy cars often rode on six wheel trucks, to give a smoother ride on the stick rail of the era.   Also, consider the fact that the three inch difference in wheel diameter only raises the axle center 1.5 inches.  If the scale three inch difference in wheel diameter is considered insignificant, why should a scale 1.5 inches be such an issue in coupler height?  Experience with equipment of many HO manufacturers, past and present, prove that over half of the couplers don't meet the "recommended standard" height.  I've sanded down or replaced a lot of body bolsters to lower cars that were too high, and mounted shims IN the draft gear box to raise the shanks of couplers that sagged too low.  If necessary, removal and replacement of the draft gear box was preferrable to offset shank couplers or red or gray shim washers.  Not knowing your views on prototypical accurracy,I offer this.  When you come to a decision such as this, think long term vs. "right now".  Spend your money and time once, on a decision you can live with ten or twenty years from now instead of a temporary fix for right now that will be revisited in the future with your time and money.

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Posted by NWP SWP on Friday, May 11, 2018 10:33 AM

The passenger cars are old IHC cars, I doubt they have scale wheels stock, also they'll only be running as a consist so if the couplers are a little "low" as long as they arent getting caught on stuff it should be fine, I mean 1.5 inches in HO is 0.017241379 inches, I highly doubt .017 inches will seriously impact anything, let alone anyone noticing.

my bigger issue is converting to Kadee body mount couplers instead of Talgo. And the hardest is going to be getting the observation car to have an operating coupler on the tail end, why? Because there's a dummy coupler there that's glued on and is surrounded by skirting. I figure I'll have to carefully carve out a slot for a coupler.

Steve

If everything seems under control, you're not going fast enough!

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Posted by NWP SWP on Friday, May 11, 2018 11:14 AM

This is the observation car.

Steve

If everything seems under control, you're not going fast enough!

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Posted by mbinsewi on Friday, May 11, 2018 11:34 AM

See if this helps with coupler conversion.  It's from Kadee's site. 

https://kadee.com/conv/pdf/i141.pdf

As far as the rear coupler, it looks like some type of pin holds it there.  Maybe with the body shell off, you can drive the pin through.

Mike.

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Posted by Anonymous on Friday, May 18, 2018 7:20 PM

NWP SWP
I highly doubt .017 inches will seriously impact anything, let alone anyone noticing.

Considering the spec is +/- .017, you could have problems with an already low car.

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-2_2010.09.pdf

Trip pins will be the first thing that causes problems, usually catching on turnouts or grade crossings.  Uncouplings may or may not happen, depending on how smooth the transistion between level and not level track is and if the couplers are all the same height.

That said,  I put intermountain 33" wheels on all my accurail cars and had no issues.  Those IHC cars look like they have 33" wheels from your pictures.  It will just depend on how you mount the couplers.

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Posted by SeeYou190 on Friday, May 18, 2018 7:34 PM

0.017" sound small, but it is almost one half of a millimeter, and is noticeable, and in HO scale it will effect perfomance.

.

+/- 0.002" should be your goal.

.

Try to find a good used Mitotoyo or Central dial caliper in a pawn shop, and learn how to use it.

.

0-6" will do almost everything you need in the hobby.

.

-Kevin

.

Living the dream.

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Posted by garya on Sunday, May 20, 2018 11:13 PM

FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

I can't help you with the resistors, sorry. One of my friends uses current sensing, and I believe he was super gluing surface mount resistors to Intermountain metal wheels. I'll ask him about it the next time I see him.

As far as passenger cars, I use 36" wheelsets, Kadee, Intermountain, or Proto 2000. I can see the difference, and it bothers me, so I changed out the wheelsets on my Rivarossi and Con-Cor passenger cars. I did have to shave down the brake shoes, though. If you want to use 33" wheelsets on your passenger cars, though, do it and sleep well at night.

Gary

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Posted by Anonymous on Monday, May 21, 2018 9:18 PM

garya
FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

They do not work in some Atlas cars.

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Posted by jdr3366 on Monday, May 21, 2018 9:40 PM
DavidMurry: "33 inches scales to .38 inches 36 inches converts to .41 inches." That's the key to this question. Measure the diameter of the existing wheels.
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Posted by garya on Tuesday, May 22, 2018 4:57 PM

BMMECNYC

 

 
garya
FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

 

They do not work in some Atlas cars.

 

Upthread the OP said he wanted to convert Accurail cars, hence my reply.  Later on he mentioned IHC passenger cars.  I'm not certain about IHC, but nowhere did he mention Atlas.

Gary

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Posted by Anonymous on Tuesday, May 22, 2018 6:44 PM

garya
FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

This statement implies that you can use intermountain wheelsets in any HO car.  When you said everything, the OP may actually think you mean everything.

If you were to say everything made by Accurail, I would not disagree.  I have had 0 issues putting intermountain wheelsets in Accurail cars.  

I should have been more specific as to why I was making the comment in the original post.  

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Posted by garya on Wednesday, May 23, 2018 2:23 PM

BMMECNYC

 

 
garya
FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

 

This statement implies that you can use intermountain wheelsets in any HO car.  When you said everything, the OP may actually think you mean everything.

If you were to say everything made by Accurail, I would not disagree.  I have had 0 issues putting intermountain wheelsets in Accurail cars.  

I should have been more specific as to why I was making the comment in the original post.  

 

Sigh Fair enough.  How about, "if you want to use these in everything you own, that's fine."  Or "if you want to use 33" wheels in everything, that's fine." 

Gary

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Posted by Anonymous on Thursday, May 24, 2018 7:38 PM

garya

 

 
BMMECNYC

 

 
garya
FWIW, 33" Intermountain wheelsets work just fine in Accurail cars. I have bunches of Accurail 40' boxcars, and I used Proto 2000 metal wheels until I ran out, so I bought a bulk pack of 100 Intermountain wheelsets. If you want to use these in everything, that's fine.

 

This statement implies that you can use intermountain wheelsets in any HO car.  When you said everything, the OP may actually think you mean everything.

If you were to say everything made by Accurail, I would not disagree.  I have had 0 issues putting intermountain wheelsets in Accurail cars.  

I should have been more specific as to why I was making the comment in the original post.  

 

 

 

Sigh Fair enough.  How about, "if you want to use these in everything you own, that's fine."  Or "if you want to use 33" wheels in everything, that's fine." 

 

As stated above.

SeeYou190

0.017" sound small, but it is almost one half of a millimeter, and is noticeable, and in HO scale it will effect perfomance.

.

+/- 0.002" should be your goal.

.

Try to find a good used Mitotoyo or Central dial caliper in a pawn shop, and learn how to use it.

.

0-6" will do almost everything you need in the hobby.

.

-Kevin

.

 

But since everything he already has uses 33" wheels, it probably would not hurt to acquire enough for his accurail cars and try them in the passenger car.  If they dont work, nothing is lost, because you just put them in the freight cars.

33s on the IHC cars may actually make it easier to body mount the couplers (or it might not).

If the cars are designed by 36" wheels, you'll end up shiming the car up which can be a pain (again I understand Steven only has Accurail and the IHC cars, so this should not be an issue at this time).

I would concur that a set of dial calipers is not a bad thing to have around if you will be doing a lot of this type of work.  Mitutoyo is a good brand if you can find them inexpenisively.  Precision measuring tools can represent a sizeable investment, I would not recommend a plastic one, as you will find yourself replacing it with metal later.

I bought a Starrett for myself, but Ive used both at work.

 

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