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Author Topic: Jensen #70 Steam Engine Ball Bearing Modification  (Read 336 times)

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Jensen #70 Steam Engine Ball Bearing Modification
« on: October 07, 2020, 10:40:56 pm »
This Jensen #70 I converted from electrically fired (when the heater failed) to gas/flame fired.

Seeing the mods that Bruce (Saint Paul Steam) always comes up with continuously with his Jensen creations, I reached out to Bruce
and asked exactly the bearings that I needed, lots of PM's back and forth with what to buy and some hints and tricks that Bruce has learnt
along the way, I was all set for my first conversion. And finally the eBay purchased packet of bearings arrived yesterday on the slowest boat from China that ever left Wuhan!

Runs very very smoothly with the axle running in the ball bearings, these Jensen #70's are real steam spitters and those drops are hot....thinking now how to
tackle that exhaust mod.

_______________________________________________
Cheers.
Jim

Blue Heelers Model & Toy Steam Engine Room YouTube Channel -
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Re: Jensen #70 Steam Engine Ball Bearing Modification
« Reply #1 on: October 08, 2020, 12:40:53 am »
Great video Jim, and well explained on how to install the bearings

Looking forward to your exhaust mod, I think it would be neat plumbed to the stack. I believe Bruce has also installed deflectors on his Jensens for the spitting exhaust.
Nick

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Re: Jensen #70 Steam Engine Ball Bearing Modification
« Reply #2 on: October 08, 2020, 12:53:55 am »
You've really tuned that one up nicely.

For spit protection I've used a notched and split section of neoprene tubing that just sort of grips the port block and drains down into a .50 cal shell, which then fills up way too soon, but it's a start.
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Re: Jensen #70 Steam Engine Ball Bearing Modification
« Reply #3 on: October 08, 2020, 06:34:52 am »
nice mod Jim, one thing I do that could help you is I loose the flat washer between the axle hub & bearing , I also turn off about 2K" from the hub (because of the added thickness of the bearing) which tends to make the oscillating mating surfaces a bit unparalleled  as you experienced earlier & let steam escape , and then again I also turn the hub snout down to have just a slight lip to ride against the inner bearing collar (about another 1K) , don't forget to adjust the stanchions to get as parallel as possible...once done correctly you should be able to turn the engine frame horizontally & the axle just slides right through & out. (this takes the most time)
Bruce, St. Paul Indiana, USA
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Re: Jensen #70 Steam Engine Ball Bearing Modification
« Reply #4 on: October 08, 2020, 04:21:50 pm »
Thanks Nick & Daniel.

Thanks Bruce, I have some more question coming your way mate about the next Jensen mod.
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Cheers.
Jim

Blue Heelers Model & Toy Steam Engine Room YouTube Channel -
 https://www.youtube.com/user/Blue123Heeler/videos


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Re: Jensen #70 Steam Engine Ball Bearing Modification
« Reply #5 on: October 08, 2020, 09:22:50 pm »
Thanks Nick & Daniel.

Thanks Bruce, I have some more question coming your way mate about the next Jensen mod.
Happy to help anyway I can .
Bruce, St. Paul Indiana, USA
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