Bachmann N Scale Doodlebug replacement gears?

[Sumner]

The webpage to buy the gears for James' page goes to a Shapeways (dead) link. I sent him an email on June 5th and have not received a response. Your "more info from James" links aren't working, the full url is missing. However, I'm pretty sure I've already read the information he had posted.
-alex-
Alex M. Postpischil
Winston-Salem, NC

I think the link is fixed but yes you probably already saw it.  I've been in touch with him before but been a couple years now.

Sumner

[Chris333]

Would love to hear from anyone with long term use of a 3D printed gear. I've never tried it myself. I understand if you either do it or toss the model it is worth a try. Just wonder how it holds up. I've see whole 3D printed On3 Shay's with 3D printed gears that work.

[peteski]

Would love to hear from anyone with long term use of a 3D printed gear. I've never tried it myself. I understand if you either do it or toss the model it is worth a try. Just wonder how it holds up. I've see whole 3D printed On3 Shay's with 3D printed gears that work.

I'm also worried about the durability of 3D printed gears in the long run. I know that FUD-printed gears integral with axle tubes holding the axles can  crack just like the original Nylon gears.  I did a fix for Lee some years ago. https://www.therailwire.net/forum/index.php?topic=46293.msg660666#msg660666

[garethashenden]

I imagine that the strength of 3d printed gears is directly tied to the material used. One of the high strength "tough" resins for instance, rather than the fine detail ones.

[albabe63]

I think the link is fixed but yes you probably already saw it.  I've been in touch with him before but been a couple years now.

Sumner

Links fixed, thanks. Yes, I already read those. I think they were the first things to come up in my original search. His last blog post was in 2020, so not sure I'll ever hear from him. I sent another note yesterday (though the website, first was through email).
-alex-
Alex M. Postpischil
Winston-Salem, NC

[Sumner]

I imagine that the strength of 3d printed gears is directly tied to the material used. One of the high strength "tough" resins for instance, rather than the fine detail ones.

I used Siraya Tech 'Build' sonic grey on the gears I made.  Actually use it on everything.  It has great detail, you can drill and tap it, if you don't over-cure it stays somewhat flexible and yet is strong.  I ran the loco an hour or so and did what you shouldn't do and put it into forward and reverse at speed to 'shock' the gears.  All was good. 

How long will they last?  Have no idea and probably won't run this engine 3 hours in the rest of my time here.  I have spares (costs pennies to print) although I do wonder how much/if resin gets more brittle over time even sitting in a dark container?

There are probably better resins than what I use but for N scale you still need good detail on the gears.

Sumner

[jwaldo]

I used Siraya Tech 'Build' sonic grey on the gears I made.  Actually use it on everything.  It has great detail, you can drill and tap it, if you don't over-cure it stays somewhat flexible and yet is strong.  I ran the loco an hour or so and did what you shouldn't do and put it into forward and reverse at speed to 'shock' the gears.  All was good. 

How long will they last?  Have no idea and probably won't run this engine 3 hours in the rest of my time here.  I have spares (costs pennies to print) although I do wonder how much/if resin gets more brittle over time even sitting in a dark container?

There are probably better resins than what I use but for N scale you still need good detail on the gears.

Sumner

The detail aspect is the tricky bit. Siraya Tech Blu is absolutely indestructible after curing, but it's so viscous that I haven't even had luck printing HO scale gears with it. I recently switched to Build as my main resin (after seeing your results with it, incidentally!), but I haven't had time to re-try my backlog of replacement gears with it yet.

[u18b]

The gears I had printed in Poland have taken a lot of use and wear in my Shays.

So far, no problems.   

Though they are simple flat gears.... a bit different from these.

[GGNInNScale]

Check Northwest Short Lines.  They have a wide assortment of gears in different materials.
https://nwsl.com/pages/about-us

[peteski]

It is not just the gear. It also has an integrated axle tube and it has to be made from insulating material.

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