Re: HO code 88 wheels

Kenneth Montero

While NMRA does have standards for most parts of a wheelset (Standard S-4.1, S-4.2, and S-4.3, go to

NMRA does have a recommended practice for axles: RP 24.3. Here is a link to that RP:

Ken Montero

On 01/02/2022 1:17 PM Ken Adams <smadanek44g@...> wrote:

Bruce, Brian, 

I only said the Moloco 1.005" length axel wheels worked in the Tichy Andrews trucks. I realize there is no common standard let alone a recommended practice for axel length amongst maker of North American HO freight (or passenger?) trucks. Is there a Proto87 standard?

In my UK prototype modeling, 4 mm scale brass cone and hat style wheel bearing inserts for pointed axels are available and are required for many goods wagon kits. The axel length was variable according to the modeling track gauge standard the modeler follows (OO, EM or P4.)  I have had no reason yet to test the UK inserts on any of my NA models to correct axel length issues. 

I usually use Tahoe trucks (omitted from the table above but I understand they use IM wheelsets) when the prototype being modeled is available in the Tahoe line and they come with the choice of .110 and .088 wheelsets.  Having the Tichy Andrews trucks (which are very nice moldings) on hand with a pack of Moloco wheels purchased to try them out was a fluke.
Ken Adams
Still in splendid Shelter In Place solitude, about half way up Walnut Creek

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