Author Topic: Senft "Poppin" engine  (Read 10976 times)

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #15 on: March 12, 2018, 06:56:23 PM »
And a few more---




Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #16 on: March 12, 2018, 07:01:03 PM »
And considering that there were a couple more set-ups that I didn't photograph, that is a heck of a lot of work for something so small. I planned on making the cast iron cylinder today too, but I have to stop and grab some lunch (It's 3:00 PM here). I don't know if I'll do amymore today or not.

Offline crueby

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Re: Senft "Poppin" engine
« Reply #17 on: March 12, 2018, 07:05:28 PM »
Wow - Brian, very busy day! And its only midafternoon!

Offline b.lindsey

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Re: Senft "Poppin" engine
« Reply #18 on: March 12, 2018, 07:06:45 PM »
Just think of it as the hardest part being done :)

Bill

Offline Steve F

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Re: Senft "Poppin" engine
« Reply #19 on: March 12, 2018, 07:24:34 PM »
Hello Brian

I used ball bearings in my engine. If you do, remember to remove the seals from the bearings to reduce friction. I also used ball bearings on the valve spindle and the cam follower. I also modified the cylinder head. Make 2 and bolt them both on top of the cylinder. The top one has a channel cut in it to allow the valve to slide between the two head plates to keep the valve aligned.

Great progress so far.

regards
Steve

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #20 on: March 12, 2018, 07:39:19 PM »
I can't think of any good reason not to have a sexy cylinder---

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #21 on: March 12, 2018, 09:18:59 PM »
The sexy cylinder is under way. Now I have to make a 5/8" expanding mandrel to mount it on so I can turn the radius on the big end.


Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #22 on: March 12, 2018, 10:54:47 PM »
Here we have the sexy cylinder finished except for the tapped holes in each end. It is still mounted on the expanding mandrel in the picture.

Offline b.lindsey

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Re: Senft "Poppin" engine
« Reply #23 on: March 12, 2018, 11:42:47 PM »
Cylinder looks good Brian! The tapered shape shouldn't change the performance that I can see.

Bill

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #24 on: March 13, 2018, 03:00:08 PM »
This morning yielded a cylinder head. Nothing very fancy compared to some cylinder heads I have made, but it should get the job done. How do you like my cylinder?

Offline bent

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Re: Senft "Poppin" engine
« Reply #25 on: March 13, 2018, 06:22:02 PM »
Nice!

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #26 on: March 13, 2018, 09:11:11 PM »
Today I made flywheels. I can't even imagine it, but that's a full 8 hours of my time. These flywheels are somewhat unique, because the hubs will be made as separate pieces. Maybe I'll make them tomorrow.

Offline NickG

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Re: Senft "Poppin" engine
« Reply #27 on: March 14, 2018, 05:30:26 PM »
Flying as usual Brian, looks good. I was apprehensive about the flywheels but that method with the separate hub worked great! As I said, I liked Poppin so much I built two! You’ll find very different results with this engine. Mine is cast iron cyl with graphite piston. It starts straight away from cold.

Steve, love the scaled up version.

Nick


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Offline crueby

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Re: Senft "Poppin" engine
« Reply #28 on: March 14, 2018, 05:32:29 PM »
Lots of progress for just a couple of days!

 :popcorn:

Offline Brian Rupnow

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Re: Senft "Poppin" engine
« Reply #29 on: March 14, 2018, 05:44:42 PM »
Nick--I was wondering about piston material. I still have 11" left of the piece of 1" diameter machinable graphite that I ordered for the Ridders engine. If I use it in the Poppin, will it work okay? I assume that if I use the graphite piston I won't need any lubrication.