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[rail450]

Hi Joe,

your new loco is running fine - but I´m getting stomachache when I´m looking at the bearing bores:

how long will a plastic axle run in a epoxy bore?

the harsh epoxy surface will grind down the gear axles over time - very very sure

BR,

Siegfried

PS: what is the total reduction ratio? 15:1 ?

[MMBUFBerlin]

Hello Joe, what is the diameter of your drive wheels? 3.2mm would be true to scale 1:450. And how many teeth have the gears of the driven axles? If there are only 10 teeth, the reduction is only 2.4: 1! Then the motor must really be from a other star, because your GG1 drives in the video really satisfactory.
By the way, it's not right what Siegfried wrote. The big gear is convex, but also wide, so it must be convex. Narrow gears also drive the bogie correctly without being convex.

[rail450]

Hi Uwe,

sorry - I did several tests:

the convex gear in combination with a turning bogie is running much better than a smaller gear without convex face

convex wide gear is better than square sharp-edged small gear

BR,

Siegfried

PS: pls, test first and criticise than

[MMBUFBerlin]

Du bist schon ein elender Rechthaber, Siggi! (-:
Was bleibt denn noch übrig von der Krümmung, wenn das Zahnrad nur noch ein Drittel der Dicke hat? Ist doch vernachlässigbar!
Aber dokumentiere deine angeblich durchgeführten Tests doch bitte mal per Video!

[MMBUFBerlin]

Wide and convex vs narrow and not convex:

wide gear convex vs narrow gear not convex

WideAndConvexVsNarrowAndNotConvex.jpg (178.46 KiB) Viewed 1470 times

It is practically the same!

[MMBUFBerlin]

Much more important for a good drive is that behind a very large gear not a very small gear is placed.

drive versions

Drive.jpg (77.94 KiB) Viewed 1465 times

[JoeMalinchak]

Hi Siegfried,

I am using a material called Garolite for my models. The material cuts easily on my laser, and is great for prototyping. I have well over an hour on my GG1 with no wear, and my 4-6-2 Pacific steam locomotive is still running fine after two years of running! Actually, they only part on the locomotive that I had to replace was the brushed motor, but this is to be expected.

The gears may fail over time, and it will be a good test to see when, but for now the material is working great. If they fail, it’s not that big a deal to replace them, or build a new chassis. However, I may explore some other materials.

This is information from the McMaster-Carr web site that sells this material. These Garolite sheets are made of a phenolic resin with cotton fabric reinforcement, which makes it easy to machine into mechanical parts, such as pulleys, gears, bushings, and washers.

Joe.

[JoeMalinchak]

Hi Uwe,

This was a side project for me, as I actually had to put aside my other projects to work on this model with Jesse. I had several goals for the GG1. One was to design a working drive unit for the model without spending a crazy amount of time on it. Although I did! Next was to use as many commercially available parts as possible to keep it simple. I also wanted it to look as scale as possible. With that said, making the drive wheels a scale size was an issue we faced, and I discussed this with Jesse several times. The steam wheels that TGauge.com sells are to large and looked way out of place, and the wheels with the geared axles are to small. We looked at this and decide just to go with the small wheels with the geared axles that TGauge.com sells. I mounted them low in the scale bogie, and they look good. Not perfect, but good from almost any distance in this scale.

My first prototype used the stock motor out of the 35.5mm chassis, and it provided enough power to run the locomotive. However, the new motor gives it much more power, and better low speed performance.

Good information on your gear placement.

Joe.

[dkightley]

Joe

Those main bogies are exactly what we need for retro-fitting to power units to give a Co-Co wheel arrangement! Any chance of making them available???? Or sharing how you made them.....

[JoeMalinchak]

Hi Doug,

The scale looking bogies were another challenging issue with this project. I first used the parts from a power transmission bogie P-035-01. The metal plates are just glued into the 3D printed frame. I cut one of the plates in ½ for the remaining wheel set. However, the 3D material was to flexible to work on the driving bogie, and I quickly realized that the pins that stick up on the bogie are needed to keep the gears from shifting on the large driving gear. A simple solution to all this was to just sand down the side frame’s of the P-035-01 bogie almost down to the metal plates. Then the bogie just drops into the scale bogie frame, and can be glued in at the correct height. One note, I had to use a small drop of CA glue applied in the center of the metal plates to hold them in place. You need to do this before you sand down the frames. As for the third wheel set, it will use a pin point wheel that will fit into the 3D printed bogie. We will see how the new bogies work on GG1 when they arrive. I think it would be great if Jesse adds them to his list of products, as I think people would want them?

Joe.