KTM Boxpok Drivers (p:48)

That’s talent Sarah,.....beautiful work!...that’s an often overlooked detail....nice!.

Pat

You sure those centers cannot be soldered?  Most look to me like plated brass.  Nice work - I admire folks who can make Proto-48 work.

Very very nice.

Ron H

Sarah, you truly are an artist combined with a very skilled craftswoman.

Yves

Outstanding work as always Sarah!

With two motors, decoders and speakers you'll be able to do neat things like this wheel slip by Linton Towell using LS decoders:

Sounds pretty decent in HO so I imagine it'll be amazing with a couple of the biggest Tang Band speakers you can squeeze into a  1:48 loco. 

Pete

beautiful drivers and beautiful work

Sweet! Nice work.

I didn't know KTM used the same size drivers for both their Big Boy and Challenger? Are the tires a different thickness? Good to know.

@Pete M posted:

Outstanding work as always Sarah!

With two motors, decoders and speakers you'll be able to do neat things like this wheel slip by Linton Towell using LS decoders:

Sounds pretty decent in HO so I imagine it'll be amazing with a couple of the biggest Tang Band speakers you can squeeze intRo a  1:48 loco. 

Pete

Thank you Pete, that’s a fantastic idea!! :-)

@bob2 posted:

You sure those centers cannot be soldered?  Most look to me like plated brass.  Nice work - I admire folks who can make Proto-48 work.

You are right, It is possible to solder them by machining off the plating – but applying a lot of heat to the centers is a bad idea. I tried one and the driver threw it‘s tire. Not the insulated one, it just lost it‘s press when cooled. I fixed it with loctite nasty green stuff, fortunately prior to machining. So it’s CA or epoxy 2k glue.

@WITZ 41 posted:

Sweet! Nice work.

I didn't know KTM used the same size drivers for both their Big Boy and Challenger? Are the tires a different thickness? Good to know.

Yes, you can‘t tell them apart. Also they share various other parts, just like the prototype.

Newly milled bronze journal bearings and „hollow“ axle on first finished set of drivers.

@Sarah posted:

Dear friends,

just wanted to report from my next locomotive project - a KTM Union Pacific 4-6-6-4 where I just finished cutting tires. Making use of the advantages of "mass production" I found it a good approach to also do the wheels of the KTM 4-8-8-4 that are and exact match and therefore I can use the tooling for both models.

By studying some close up's of the 4014's big drivers I found out that the castings are missing a very visible detail of the original drivers, the actual box spoke backside. It took me some time to figure how they are constructed but there's a lot of info out there, also from the construction of the first driving wheels of the PRR T-1 by the T-1 Trust.

I use thin brass sheet material that I drill out for brass tubing that is soldered in place and then trimmed and cleaned up. Since the wheel centers are cast material that can  not be soldered I simply used CA to glue them in place. On the Challenger these are not so visible since the first driver of each engine is behind a lot of rods and the crosshead but it really makes a difference.

Next step will be the drive train where I'll try to implement two motors for individual freedom of front and rear engines. Two decoders will produce independent sound and hopefully smoke. Also have I never before painted brass, that's going to be the special thrill.

Cheers, Sarah

Sarah, you truly have a gift for making amazing trains with your hands. I salute you.....

Looking great!

@Sarah posted:

Newly milled bronze journal bearings and „hollow“ axle on first finished set of drivers.

Sarah,

This is great stuff. To my 'very limited' knowledge, only Gary Shrader was offering hollow axles in some of his incredible restorations.

You are now placing the bar very high, in term of accurate reproduction.

Yves

Thank you :-)

@Sarah posted:

Thank you :-)

SPEECHLESS......no, AMAZING.....

Some progress on UP 3951 has been made. I managed to remove the cab for backhead detailing. Not so easy. There's a lot of work going into that locomotive, PCS parts are ordered and the Demko helical geared gear box is in place. Turns out I need a geared motor since the mechanism runs too fast. I aim for a 25:1 ratio or higher. There are many options for motors out there, Faulhaber, Maxon, Pittman and Assunmotor of China.

Since the Demko gearbox is not self locking like a worm drive, I might investigate the possibility of an electrical motor brake. That would surely add to realism a lot. Huh, big project!

https://youtu.be/JvfDGXFynXY

I was always scared of soldering around an expensive brass engine but now I really enjoy it.

Sarah, that’s a crazy lookin but really cool gear box set up.....I looked through my geared Pittmans hoping I’d have a 25:1.....shortest I have is 60:1 ....might be a bit too much, ...it’s 12V and I have no use for it,.....it’s a 8000 series Pittman.......it’s a steep jump from 25 though....

beuatiful work!....right up my alley!....keep it up!..

Pat

Hi Sarah,

I need to ask you a question about something, but could not find your email in your profile. I have an idea in my head, but I need your advice to see if it could be done and if you could do it.

@DL&W Pete posted:

Hi Sarah,

I need to ask you a question about something, but could not find your email in your profile. I have an idea in my head, but I need your advice to see if it could be done and if you could do it.

sarah.griessenboeck@yahoo.de

@Sarah posted:

sarah.griessenboeck@yahoo.de

email sent

You are an amazing modeler Sarah. Hollow axles...wow!  And I love the road you chose to model.