Author Topic: Freelance Inline Twin  (Read 37873 times)

Offline yogi

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Re: Freelance Inline Twin
« Reply #30 on: November 16, 2016, 04:56:04 AM »
It's time to make some chips!  8)

I wanted to start with the crankshaft, but since the bearings I ordered haven't arrived yet, I decided to have a go at the crankcase.

To illustrate what it should look like when finished, I'll start this post with a couple renderings of the crankcase halves. Correct me if I'm wrong, but I think this will help some people to visualize the different set ups.








First, I squared the block on 3 faces. Looking at the picture below, the faces in the jaws are already finished to size. This will be the with of the crankcase, and the bottom is machined, that will be the reference for the thickness. I must admit, I didn't take a pictures while I did the squaring, as it is nothing special and I didn't think people would be interested, but it would help describe the process...   :facepalm:




I started with the inside of the two halves. The pockets which will make room for the con rod to work in are next.
Bellow a couple of "action shots" while machining. It was quite a time consuming op, as the pockets are rather deep with a small cutter. A small step over and conservative feed rate are a must...






The pockets are machined out...




...and cleaned up.




Stay tuned,
Yogi


Offline yogi

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Re: Freelance Inline Twin
« Reply #31 on: November 17, 2016, 03:53:45 AM »
The work continued on the outside of the crankcase halves:

First, milled the "flange" where the two halves will be screwed together. Second operation was the angled relief. To note here is the part is sticking out of the vice rather far. This is definitely not ideal, but doable with some caution.






The bottom half at this stage:




The same process was used for the top half of the case, except one side is different where it will house the camshaft.




The two halves put together for the first impression of where this engine is going...  8)




Stay tuned,
Yogi

Offline tvoght

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Re: Freelance Inline Twin
« Reply #32 on: November 17, 2016, 02:55:32 PM »
Yogi, I've been watching with interest. I think the 3D renderings do help to visualize the setups. Nice work so far.

--Tim

Offline yogi

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Re: Freelance Inline Twin
« Reply #33 on: November 20, 2016, 03:52:17 AM »
Thank you Tim!

The next step is to bore out the case for the crank and camshafts.

The two halves are screwed together and set up in the vise.




Bore for the camshaft first:




...and for the crankshaft:




At this stage the case was faced over to ensure the surface is perpendicular to the bore, and the hole pattern for the cover was drilled. The operation was repeated on the other side, machining the case to it's final length and drilled the hole pattern.




The last operation was to drill and bore the top to finish the case.




The finished crankcase (minus a few threads needing to be tapped  ;) )






Stay tuned,
Yogi


Online b.lindsey

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Re: Freelance Inline Twin
« Reply #34 on: November 20, 2016, 04:07:15 AM »
Wow yogi, you are moving right along. Very nice looking crankcase so far too. Staying tuned for more!!

Bill

Offline yogi

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Re: Freelance Inline Twin
« Reply #35 on: November 21, 2016, 08:20:07 AM »
Thanks Bill! It's going to slow down, as life keeps interfering with my shop time...  8)

Offline Perry

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Re: Freelance Inline Twin
« Reply #36 on: November 21, 2016, 10:31:30 AM »
Hello Yogi, nice engine there. quite simmilar to my freelace endeavour,
btw after carefull balancing there was no problem with vibrations at all.

search topic "2 cylinder OHV 29ccm"

regards
Peter

Offline Nick_G

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Re: Freelance Inline Twin
« Reply #37 on: November 21, 2016, 01:01:15 PM »
.
Impressive.  :)

Nick

Offline yogi

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Re: Freelance Inline Twin
« Reply #38 on: November 24, 2016, 09:10:42 AM »
Thanks guys!  :cheers:

Peter, yes, the engine you built has a lot of similarities to what I'm trying to accomplish. Hopefully it will turn out as nice as yours.

Here the link to Peters engine build thread for easy reference:
http://www.modelenginemaker.com/index.php/topic,4173.msg77420.html#msg77420


Regards,
Yogi



Offline yogi

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Re: Freelance Inline Twin
« Reply #39 on: December 13, 2016, 01:35:06 AM »

The work continues on the crankshaft.

First, some lathe work.
Here, the rear (flywheel end) of the crankshaft beeing turned:







The crank discs were turned next:





What will be the front end of the engine (the accessory end):



After all the parts were finished turned, it was over to the mill. I machined a set of soft jaws, to be able to hold the part accurately on the bearing seat. It is very important that the hole for the crank pin is not only accurate in diameter, but also exactly perpendicular, for everything to line up when assembling the crankshaft.



Two of the discs where drilled to be tapped, and two countersunk.



The front and rear part being finished as well:





The different parts, ready for assembly:



...and the assembled crankshaft:



The crankshaft installed in the crankcase:





To demonstrate how free its running, a short video:


I'm very pleased how the crankshaft and the project has turned out so far, and hope the rest of the engine will go as smooth...

Stay tuned,
Yogi

Offline steamer

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Re: Freelance Inline Twin
« Reply #40 on: December 13, 2016, 02:06:32 AM »
Oh I am definitely gonna do an engine with a crank like that.....That's slick!


Nice Job!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Roger B

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Re: Freelance Inline Twin
« Reply #41 on: December 13, 2016, 09:35:45 AM »
Very nice  :praise2:  :praise2: Your hand gives a good idea of the size of this engine.
Best regards

Roger

Offline Orloff

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Re: Freelance Inline Twin
« Reply #42 on: December 13, 2016, 05:19:39 PM »
Well done, I'm speechless. That is impressive.

Offline Admiral_dk

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Re: Freelance Inline Twin
« Reply #43 on: December 13, 2016, 07:47:20 PM »
Looking really good Yogi  :praise2:

Can you tell me what size bearings you used here ?

Best wishes

Per

Offline fumopuc

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Re: Freelance Inline Twin
« Reply #44 on: December 13, 2016, 07:54:34 PM »
Hi Yogi, very nice and precise job. First time I have the possibilty to see someone making this crank concept of Mr. Schillings. His book is now since 4 or 5 years on my desk.
« Last Edit: December 14, 2016, 04:39:26 AM by fumopuc »
Kind Regards
Achim