Author Topic: Freelance Inline Twin  (Read 36278 times)

Offline Art K

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Re: Freelance Inline Twin
« Reply #180 on: March 31, 2018, 11:57:14 PM »
Yogi,
I have to admit to me the path of least resistance would be not making it myself, thus the computer radiator sounds like a great idea.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Rustkolector

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Re: Freelance Inline Twin
« Reply #181 on: April 01, 2018, 01:25:59 AM »
Yogi,
I vote for the Jerry Howell design radiator, but only for its great looks. The 120mm computer radiators will get rid of a lot of heat with little air flow. I have three engines using them. Regarding your pump seal, I have built 5 of Jerry Howell's brass gear pumps. On the first three I used a standard O-ring behind the driven gear. All three leaked to some degree. Jerry said he used an O-ring out of a Bic butane lighter and it never leaked. In my case one leaked pretty quickly, the other two leak but to varying degrees at different times (?). The last two pumps were built with lip type oil seals and have not leaked a drop. I since learned that O-rings can be used for rotary seals but require a harder material, and they should be installed in a close tolerance full O-ring groove. The latter requirement was beyond my skill level on .125" dia. shaft bores. I have recently replaced my worst leaker with a new pump and lip seal. No leaks so far. The only problem I find with the lip seals is that they are a bit expensive.
Jeff 

Offline Zephyrin

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Re: Freelance Inline Twin
« Reply #182 on: April 01, 2018, 08:49:25 AM »
Thanks for this instructive thread Yogi, amazing level of skill, and a beautiful engine.

Rustkolector:
I do have a similar experience with leaks on 3 tiny water pumps I did, all fitted with plain O ring...thanks for suggesting oil lip seals!

Offline Plani

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Re: Freelance Inline Twin
« Reply #183 on: April 01, 2018, 12:29:19 PM »
That's a beautyful looking pump, Yogi  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Plani

Offline yogi

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Re: Freelance Inline Twin
« Reply #184 on: April 01, 2018, 01:50:32 PM »
Thank you guys for the comments!  :cheers:

Chuck, the gear is 10 Teeth, 24 D.P., 14.5 Pressure Angle. The shaft diameter is 4mm. The blind hole is milled to size with a circular interpolation on the CNC mill.

Jeff, thank you very much for the information on sealing your pumps. I will definitely take that into consideration. Where do you source lip seals, as small as we use?

Regarding the radiator, I agree with both of you, Art and Jeff. I like the fact that the computer radiator will be much less work, but the looks of the Howell radiator is hard to beat.


Thank you all for the input,
Yogi

 

Offline Roger B

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Re: Freelance Inline Twin
« Reply #185 on: April 01, 2018, 02:56:56 PM »
Excellent Pump  :praise2: I am just about to start on the water pump for my twin. This will use Delrin gears which removes any corrosion problems but does require a little more clearance to allow for thermal expansion.
For the last pump I was able to source 6mm bore 10mm OD 2mm thick lip seals from a normal bearing supplier. The same supplier also offers 4mm bore but somewhat more expensive.
Best regards

Roger

Offline yogi

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Re: Freelance Inline Twin
« Reply #186 on: April 01, 2018, 03:15:08 PM »
Thanks Roger!

I already found small lip seals and ordered a couple. I just wasn't looking in the right place.  :atcomputer:
With 4mm ID 8mm OD and 2mm wide, the seal is not much bigger than a O-ring. Modifying the pump housing to accept the seal will be easy.

Thanks everyone for the input!
Yogi


Offline kuhncw

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Re: Freelance Inline Twin
« Reply #187 on: April 02, 2018, 03:17:01 AM »
"Chuck, the gear is 10 Teeth, 24 D.P., 14.5 Pressure Angle. The shaft diameter is 4mm. The blind hole is milled to size with a circular interpolation on the CNC mill."

Yogi, 

Thanks for the pump gear information.  I'd not thought of milling the blind holes as they are so small.  I'll give that a try, now that my Taig mill has ball screws.

Chuck

Offline yogi

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Re: Freelance Inline Twin
« Reply #188 on: October 11, 2018, 08:10:47 PM »
With a crazy busy summer at work, progress on the engine has been virtually non existent.
I was finally able to spend some time in the workshop this week, and can show some progress. Work continues on the cooling system.

First order of business was to modify the pump housing to accept a lip seal, as suggested by Jeff above.



Before and after installation of the lip seal:






Next, I made the plumbing to connect the pump output to the cylinder block passage.
Milling the fitting to the cylinder block:








The original plan was to bend tubing from the pump to the inlet fitting, but that was an utter failure due to the small radius in my design. As solution, I made an elbow to be able to make the corner around the cylinder block.











The finished elbow



The plumbing installed on the engine:





Thanks everyone for their patience following along, and stay tuned for more...

Yogi





Offline Roger B

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Re: Freelance Inline Twin
« Reply #189 on: October 11, 2018, 08:15:06 PM »
Glad to see you back on this one  :ThumbsUp:  :ThumbsUp: I have a similar problem with the connection from my water pump to the cylinder block  :headscratch:
Best regards

Roger

Offline Ye-Ole Steam Dude

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Re: Freelance Inline Twin
« Reply #190 on: October 11, 2018, 09:08:14 PM »
Hello Yogi,

Nice update and glad to see you back in the shop.

Have a great day,
Thomas

Offline toolznthings

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Re: Freelance Inline Twin
« Reply #191 on: October 12, 2018, 01:05:10 AM »
I like it !  :cartwheel:  :cartwheel: Nice work.  :ThumbsUp:
Thanks for the visit !
Brian

Offline Rustkolector

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Re: Freelance Inline Twin
« Reply #192 on: October 12, 2018, 02:41:40 AM »
Yogi,
In looking at your photo of the water pump housing with the seal installed, you have the seal in backwards. The lips should be on the liquid side. Maybe you already knew this. I thought I would mention it just in case.
Jeff

Offline Art K

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Re: Freelance Inline Twin
« Reply #193 on: October 12, 2018, 03:51:02 AM »
Yogi,
Glad to see you are making progress again. I have a friend in tool & die he is crazy busy as well.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline yogi

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Re: Freelance Inline Twin
« Reply #194 on: October 12, 2018, 05:28:54 PM »
Thanks guys for the kind comments, it's very much appreciated.

Jeff, Oh boy, I sure wasn't paying attention. Thanks for pointing it out.

Art, I'm glad to hear your friend is busy. That's much better then the opposite. I don't work in the metal industry any more, not that the aviation industry is any less stressful though...  :thinking:


Yogi