Nn3

[garethashenden]

Does it run? The quartering looks way out. Wheels one and three look ok, but the middle one is off. Are both 2 and 3 geared? I bet its one tooth off.

[Chris333]

It ran and then I removed the rear pilot wheel, it was a 2-6-2. So Maybe I just didn't get it back in place before putting the cover plate back on.

[peteski]

I'm amazed with their Z scale valve gear detail. It is really impressive.  They have come a long way from their original 0-6-0!

[Chris333]

They did that one with valve gear and coreless motor as well:
https://www.marklin.com/products/details/article/88001

The motor is horizontal in the new one.

[peteski]

They did that one with valve gear and coreless motor as well:
https://www.marklin.com/products/details/article/88001

The motor is horizontal in the new one.

Pretty impressive!

[Chris333]

Since you brought up the old Marklin 8800. There used to be a Nn3 white metal kit to turn one into a D&RG 0-6-0T. Well the EBT had an identical locomotive except for the cab side paneling:


I got the very stupid idea to take a Toma N scale 0-6-0 kit and turn it into Nn3:
https://tomamw2.com/products/1361
These run great and slow. The wheel base is very close. The motor needs slid forward. Oh and the whole thing needs narrowed.

The black chassis is the stock Toma chassis. The other is my new Nn3 chassis:



I first asked Toma to make these for me and his excuse was the thinner frame had no way to mount pick-ups.  So this is my other stupid idea to sandwich the pickups between the frame and bottom cover with grooves to hold it in place.

Not ideal, but might work. Just today I cut the axles shorter on my lathe so these are fresh pics. Need to get the side rods back on.

And this is a crappy test body print at the wrong angle and large layer heights.

[peteski]

If your electric pickups work reliably (I see no reason why they shouldn't), you are an engineering genius!  Those pickups are on the bottom of the frame. Did you leave some room there for the pickup wire to flex a little?  As I see it, that would reduce friction and improve contact reliability.

[dem34]

My only quibble with that arrangement is when you have tension there tends be a condition where the wire contacts one point but not the 2 others. My 2 inexperienced cents is doing 6 contact fingers but 2 strips of copper tape on the base plate. So there would be constant contact on all wheels and the tension can be adjusted by backing off or tightening the plate.

[Lemosteam]

My only quibble with that arrangement is when you have tension there tends be a condition where the wire contacts one point but not the 2 others. My 2 inexperienced cents is doing 6 contact fingers but 2 strips of copper tape on the base plate. So there would be constant contact on all wheels and the tension can be adjusted by backing off or tightening the plate.

Based on what I can see of Chris's design, the axles appear to have no vertical float (short wheelbase) and the wire will always be in contact with the busing on the axle, which is always in contact with the bushing.

[randgust]

What is the 'stock' driver diameter and wheelbase of the Toma N 0-6-0?

I have been contacting them to get data with minimal success, did find out they won't sell the chassis separately.

I'm still looking at building HVRR 3, the Porter.  Not very happy with my Atlas (Micro-Ace) mechanism.

[peteski]

Based on what I can see of Chris's design, the axles appear to have no vertical float (short wheelbase) and the wire will always be in contact with the busing on the axle, which is always in contact with the bushing.

John, I don't think those are bushings.  To me those look like very thick half-axles which are single part with the wheels.  Then the axle is plastic (single piece with the gear) and it plugs into an opening in those thick axles.  Similar to how the wheelsets were made in the original Atlas/Kato RS-3 and RS-11.

[Chris333]

Yes they are wheel-axle combos. usually Toma's wipers touch the back of the wheel, but since he uses brass and I replace them with PB wire I bend them down to touch the axles. This frame is so thin (being Nn3) the screws to hold his brass pickup holder in place barely have anything to grab.

I imagine a tiny dab of silver bearing grease will save the day on my pick-ups. 
https://mgchemicals.com/products/grease-for-electronics/electrically-conductive-grease/contact-grease/

These wheels are just a hair smaller than 6mm and the total WB is 0.664", front to center is 0.345", center to rear is 0.319". He has a few other N scale kit. but they are currently sold out:
https://tomamw2.com/collections/n-gauge

This is his Japanese page:
https://www.tomamw.com/
If you see anything on there that isn't on the US site you can ask him to send you an invoice for it.

He won't sell me parts either, even though I send him all the stuff I make with his parts. He even tells me certain measurements that save me time. He's also shared links of others doing 3D. He says 3D printers are rare over there and I told him I have 5...lol.

[Chris333]

Soooo I got the rear deck drawn up and a much better body printed.



There is a warp down the side of the headlight and there seem to be dimples in each dome. I printed this at 48 degrees to match the pixels up. I might try it at half that. there is backhead detail too.



Cut the old body in half.



The rear deck slides into the cab.




The large disc covering the spur gear was acceptable, but found a way to hide it more.

Printing a rear deck with tool boxes under the cab as I type.

On the D&RG these started out as 2-6-0's that they converted into a 0-6-0T. They liked them and the rest were ordered that way from Baldwin. I found there were 2 of these 0-6-0T locomotives built for the Connotton Valley Railway in Ohio, that was the narrow gauge that became the Wheeling & Lake Erie. One of those was sold to a RR in Utah that converted it into a 2-6-0.

The Cleveland, Canton and Southern railroad (CC&S), originally the Youngstown and Connotton Valley Railway, was established in 1877 and created a line from Bowerston (south of Canton, OH) to Youngstown. The Youngstown and Connotton Valley purchased the bankrupt Ohio and Toledo Railroad in 1878, which ran from Carrollton to Oneida, and shortened the name to Connotton Valley Railroad Company (CVR). The CVR continued to expand its line, and by 1885 the Connotton Valley road had a total of 160.59 miles of narrow gauge (three foot wide) track in operation, stretching from Cleveland to Coshocton. In Cleveland, CVR tracks extended along Canal Street to the corner of Ontario and Huron Avenues, where a new passenger depot was opened in 1883. Sold under foreclosure to bondholders on May 9, 1885, the railroad renamed as the Cleveland and Canton Railway. Tracks were converted to standard-gauge over the next three years and merges with three smaller railroads in May 1892 expanded the line to Zanesville. The Cleveland and Canton added Southern to its name (CC&S) to better describe the 209.59 miles of track it now operated.


Both the CC&S and CB&T railroads deteriorated until their purchase by the WLE in 1899.

[Chris333]

Looking at the new body print under a lens. There are no dimples in the domes, must just be a shadow in the photos. The headlight warp is only on one side. Think I'll pop on a fresh FEP and try again.

[Chris333]

Now I'm making the stack and headlight separate parts. I can core the stack with 1/16" Tungsten welding rod. And make different stacks and headlights.

See this is how it works. Not just a good print, but over and over refining everything once you have the parts in hand.