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Author Topic: 2 speed transmission  (Read 12288 times)

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2 speed transmission
« on: February 02, 2023, 09:53:37 pm »
Bought an RC transmission, it has a 1:8 and a 1:4.8 and in between is a neutral. I intend to use this with the H75 engine to power a small locomotive, but with some creative planning I think it would be quite nice to use it for giving fast and low torque engines some extra torque. Everything
runs on bearings and all the gears are very hard sintered steel. I don't know if the part that engages or disengages each gear will be able to hold up to being the "clutch" of my locomotive. Thought it may be of use for y'all! https://a.aliexpress.com/_mKqrLAS [ Guests cannot view attachments ]

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Re: 2 speed transmission
« Reply #1 on: February 07, 2023, 12:13:07 pm »
An interesting project.

I look forward to hearing how it turns out.

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Re: 2 speed transmission
« Reply #2 on: March 27, 2023, 06:27:59 pm »
Well these pics are from a few weeks back, but I have not advance any further anyways, here you can kinda get an idea what my locomotive's powertrain will look like. The powered trucks are obviously the most complicated part, but with the stainless RC truck drive shafts and transfer  case, it really couldn't be much easier. I'm stuck in a spot of trying to make it functional with very little attempt at looks, or look great and take years to finish. Tough choice but I will just do it the best I care to as I go. [ Guests cannot view attachments ]
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Re: 2 speed transmission
« Reply #3 on: March 27, 2023, 07:23:13 pm »
That looks pretty cool so far, I will be watching your progression with interest.

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Re: 2 speed transmission
« Reply #4 on: March 27, 2023, 08:12:53 pm »
Yeah pretty excited about it, but there are a few big details I need to design and build before I can even work on the frame.namely I need to get power to the transmission through a clutch and a reversing mechanism. Reversing will be pretty easy, just have a switch between 2 sets of gears, one with 1 gear one with 2. Will allow me the opportunity to reduce the speed as well, it currently will travel just over a foot a second at slightly above idle (~2000rpm.) Don't really want it hauling too fast, all my track was printed for a Christmas train I made for work this year, and I made the corners VERY tight. The other detail is the powered trucks. Need to make a 90° turn from the driveshafts to the wheels. Got some gears but need to make a frame with bearings. I got the wheels from an absolutely horrendous vendor on ebay. (Ana.kramer, Roll-ez wheels) I don't need to go into that, but I am banned from buying from him because I had the audacity of asking for part dimensions before I purchased. Dude has a hell of an ego

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Re: 2 speed transmission
« Reply #5 on: March 28, 2023, 11:55:38 am »
Cool Project.

Thank you for sharing.

I look forward to the next update.

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Re: 2 speed transmission
« Reply #6 on: May 10, 2023, 05:11:11 pm »
This is a great project.

Thanks for posting it.

Would a Shay type drive gearing slow it down enough?

If not a worm gear drive ought to do it.

Both work with 90 degree offset.

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Re: 2 speed transmission
« Reply #7 on: March 07, 2024, 10:04:01 am »
Any update on this project?

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Re: 2 speed transmission
« Reply #8 on: March 08, 2024, 06:17:15 am »
Neat looking project!
Talent unshared is talent wasted.

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Re: 2 speed transmission
« Reply #9 on: October 13, 2024, 09:28:57 am »
I also would like to see any updates on this project if you have been working on it.
I myself also have a H 75 engine.
 I do feel that using Shay type gearing would definitely slow it down and eliminate some of the severe driveline angles you have.

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Re: 2 speed transmission
« Reply #10 on: April 18, 2026, 09:40:32 pm »
Sorry to leave you guys hanging, I have not had much progress with this in the past year, I did make some progress on machining the powered trucks, but I ran into a bit of trouble with how to mount the trucks to the frame. I havent seen many people using these beautiful little 4cyl engines for much, but I did happen across this model. Wont be for me at this price tag, but it does make you wonder if one of these engines and some RC equipment could be shoehorned in there....
The Holt 75 was equipped with a 4 cylinder gas engine that produced over 70 hp. Easily out performing round-wheel tractors, it forever changed the face of farming, logging, construction and even wa...
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Re: 2 speed transmission
« Reply #11 on: 10 hours ago »
That's a beautiful model it would be nice if somebody came out with a kit to go along with the 4 cylinder engines that gin made unfortunately gin made a major error though as he has the engines running in the wrong direction With a redesigned camshaft that could be easily corrected.