N Scale Truck Reamers?

[Lemosteam]

IIRC
the Reboxx Tool is designed according to NRMA specs
and
on their website they note the 60 degree tips
i would guess that is why 60 degrees has been mentioned
and why it would seem to be a good geometric to abide by
sincerely
Gary

Does the NMRA spec define the axle points?

[Philip H]

yes. i would be interested.
thx
Gary

Me too

[up1950s]

[garethashenden]

I think that a six flute countersink would be better in this situation. Single flute cutters have a tendency to bite and dig in more than we want in this situation. A six flute would take lighter cuts and will stay more concentric. In a milling machine with properly held parts, a single flute will give a better finish, but that's not the situation we have here.

[jpwisc]

I would also like to see this tool available for the N Scale market. I get the occasional car that could benefit from this tuning.

[wm3798]

When I saw this topic, my first thought was 

After reading it, I'm having a hard time understanding what the need is.  I have rolling stock that's going on 40 years old, and I've run it in rooms with dog hair, plaster dust, and a myriad of other hazards.

I've never felt the need to "ream" my trucks.  I have had occasion to pull some grime out, particularly from the phosphor bronze cups of a locomotive, but that's easily achieved with the business end of a toothpick (available at Walmart for 7 cents a ton, for those of you taking notes)

What on Earth, other than irreparable damage, can be accomplished with one of these things?

Sur Lee

[SandyEggoJake]

@up1950s

unless the material is a metal side frames, a burr of that profile isn't what you want.  The desired effect is a clean slice to a point, not a series of scrapes forming a bowl.

@Lemosteam

Yes, the NMRA standard for the axel point is max 50 degrees.  See https://www.nmra.org/sites/default/files/standards/sandrp/pdf/rp-24.3.pdf

@garethashenden

Six flute is overkill and would significantly jack up the price.  For anti-wander, two or three would cancel.  But wander is more an issue for a de novo hole with a power tool.  For cleaning an existing divot in plastic, the right cut angle is more important. And remember, you want a clean cutting action to the very tip of the point the cone as that is the only region that should contact the axle.  Getting six flutes to the point leave little material.

[mmagliaro]

When I saw this topic, my first thought was 

After reading it, I'm having a hard time understanding what the need is.  I have rolling stock that's going on 40 years old, and I've run it in rooms with dog hair, plaster dust, and a myriad of other hazards.

I've never felt the need to "ream" my trucks.  I have had occasion to pull some grime out, particularly from the phosphor bronze cups of a locomotive, but that's easily achieved with the business end of a toothpick (available at Walmart for 7 cents a ton, for those of you taking notes)

What on Earth, other than irreparable damage, can be accomplished with one of these things?

Sur Lee

I'm not sure what everyone else's thoughts are, but from my own experience, sometimes a wheelset is just plain tight in a truck, and changing the wheelset doesn't seem to help because the distance between the cups just isn't quite long enough.
I have actually just used a couple of pin vise bits in varying sizes to deepen the point of the cups enough to open up clearance. 

But if a ready-made reamer like this were available, it would be easier.

[narrowminded]

Single flute countersinks leave a much better finish.  They cut at the single edge while the rest of the circumference aids in smoothly guiding the cutter through its rotation.  Around a machine shop you're unlikely to see anything else.  Various angles and diameters but always single flute.  Multi-flute are for woodworking, I believe.

[Catt]

After seeing the difference my HO reamer by Re-Boxx has made in the free rolling ability of my HO freight rolling stock I want a reamer in both N and Z scales.

[up1950s]

When I saw this topic, my first thought was 

After reading it, I'm having a hard time understanding what the need is.  I have rolling stock that's going on 40 years old, and I've run it in rooms with dog hair, plaster dust, and a myriad of other hazards.

I've never felt the need to "ream" my trucks.  I have had occasion to pull some grime out, particularly from the phosphor bronze cups of a locomotive, but that's easily achieved with the business end of a toothpick (available at Walmart for 7 cents a ton, for those of you taking notes)

What on Earth, other than irreparable damage, can be accomplished with one of these things?

Sur Lee

Yeah , once in a blue moon , nothing you can't do with existing tools . If we had brass trucks then maybe , but just maybe . I would rather use Maillefer Swiss Hardened cup reamers on the axle ends if I found myself in a tight spot .

[SandyEggoJake]

I'm having a hard time understanding what the need is.

@wm3798

A fair question.  One that even the HO guys once debated. 

But the decreased rolling resistance seen after using such tools in HO - even in commercial IM POM trucks - settled that debate. 
(Data here:  http://www.reboxx.com/Documents/Wheelsets/Steam%20Loco%20Tender%20&%20Electric%20Application%20Chart.pdf)

I expect similar performance improvements in N.  Longer trains.  Less broken trains.  Less wear on the engines. 
After all, such is very easy to do once one is already committed to a metal wheelset swap campaign.

However, my urgent need is less about improving performance of commercial IM POM trucks.  My need is making acceptable divots in 3DP trucks from Shapeways.  Without work, many just don't roll. 

 

[SandyEggoJake]

Anywho....

if there is enough interest - say a dozen statements of interest here by the end of the month - I'll get pricing on having a custom run of N scale made.   And maybe a Z scale one just for @Catt!

[glakedylan]

Does the NMRA spec define the axle points?

yes...from their website
https://nmra.org/sites/default/files/standards/sandrp/pdf/rp-24.3.pdf

from their index contentspage:
RP-24 Trucks - (8/1963)
RP-24.1 Journals - (7/1982)
RP-24.2 Wheelsets - (8/1963)
RP-24.3 Axles - (7/1982) <<<----------

[Lemosteam]

@SandyEggoJake @glakedylan Thanks!  Helpful!