Author Topic: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!  (Read 976 times)

Offline Longboy

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LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« on: November 06, 2020, 09:33:04 PM »
Build season came early for me this year in August as the virus changed my routine and I needed some around the house activities to come into play long before the cooler weather comes for my usual involvement time with modeling.
So I begin with a concept.

I've taken one of these and put it into the Longboy Engine smelter......



........then I added one of these into the smelter.



Then I start to pour the combination into the mold of the mind! The WEDGE RUNNER STORY coming this weekend!     :)

Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #1 on: November 08, 2020, 06:14:54 PM »
Coming back with some 3x3x .25in. aluminum angle for WEDGE RUNNER as it's frame basis. Two bores topside for some DOM liners for one inch pistons.



And some aluminum round stock making up the radiators over the liners.



A pair of 4-40 screws hold the radiators to the deck. This is a change from a 3 screw set up I use releasing the top of engine from the deck for reasons explained later. At a right angle to the crankshaft I can get the screw driver or hex key between the crank webs to remove the screws. :ThumbsUp:



Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #2 on: November 10, 2020, 06:00:50 AM »
The cylinder head will be my hybrid flat head design effort.



I bore the combustion chambers to around .375in. depth. With the flat top pistons rising to a point about .250in. below the deck height, I get the right compression for the chamber volume presented.

From the head perimeter port into the combustion chamber. The valves are not in the combustion chamber but in a remote assembly attached to the head at the port.

Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #3 on: November 12, 2020, 02:31:33 AM »
The head is milled out around the ports to dock the valve blocks.





And the head is ready for the valves. Looks good!



Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #4 on: November 15, 2020, 05:53:06 AM »
The valve blocks bolted to the head determine the camshaft height above head. These cam towers came in from the valvetrain division with the shafts! Lobes ride on the bucket valve spring retainers threaded onto the valve stem.



Those towers look pretty high to the top of the cylinder head using 3/4 inch tall stock for the head.  :thinking:



I will raise the height of the head by making an overlay using 3/8 in. stock for a better proportioned view with these towers looking shorter then.  :ThumbsUp:
Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #5 on: November 17, 2020, 02:36:51 AM »
The holes in the overlay are over sized so the head can be removed with the overlay attached or not. Head bolts and spark plugs pass through.



A pattern of cooling fins milled in





Three socket head 4-40 screws right down the middle secure the overlay to the head then.



And the cam towers shortened up nicely!     ^-^

Wadda you mean, "It don't run"???

Offline AlexS

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #6 on: November 17, 2020, 07:23:28 PM »
Like the split flathead valve setup! I am going to follow this project  :popcorn:

Offline mnay

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #7 on: November 17, 2020, 07:26:31 PM »
I love your engine creations.  Keep us posted.
Everyday at lunch time I check the forum
Mike
Still  working for another couple of years so I do a lot of lurking and  watching others work.
More time someday soon I hope
« Last Edit: November 18, 2020, 07:40:48 PM by mnay »

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #8 on: November 20, 2020, 03:37:39 AM »
Under the deck, the crankshaft rolls along between the bearing carriers bracketed by 3/8 in. aluminum stock fastened to both the vertical and horizontal legs of the angle frame piece.



A log of crank webs to be parted off to cage the con rods. These are 1.5 inch diameter with the throw for a .75 in. stroke.



A center bearing of an Oilite bushing for the crankshaft supported by a 1/2 in. wide aluminum tower. R1810ZZ rollers for the brass bearing carriers.



For WEDGE RUNNER, smaller diameter crank webs allow the crankshaft to be placed closer to the top deck plate for a shorter lower end of the engine. The trade off here is that the piston/ rod assembly no longer can be removed or loaded from the bottom of the cylinders as the piston skirt no longer clears the webs.   :ShakeHead:




Back to the two screw over a three screw hold down of the cylinders upon the deck, you can see their access between the webs to pull the top of the engine off by disconnecting the cam drive belt. Yes, the crank can be removed to pull the piston/rod too by pulling a drive off of each crank end..... just builder's choice ease here!     :D
Wadda you mean, "It don't run"???

Offline propforward

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #9 on: November 20, 2020, 11:28:08 AM »
Fascinating watching it come together.
Stuart

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #10 on: November 21, 2020, 04:57:53 PM »
The drive from the crankshaft to the flywheel is done by a pair of XL 18T sprockets. Wanted a more substantial belt here than using the MXL sized belt and sprockets.



Ya, that looks pretty meaty!



At the backside of engine another pair of towers for the bearing carriers and the shaft for ign. points cam and flywheel.



Flywheel is 3in. diameter steel unit.

« Last Edit: November 21, 2020, 05:45:15 PM by Longboy »
Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #11 on: November 24, 2020, 03:25:15 AM »
This is my 1st. twin cam engine. 20/40T MXL sprockets and belt. I order the belt running some thread over the sprockets with cyl. head torqued down and idlers in place, measure its length. In the photo, I have a spacer under the radiators to raise the camshafts to take up the slack, testing out the appearance minus the idlers.



Looks like three stories of stair steps to get from the crank to the cams! I go back to the original plan with the idlers and pull the spacers. I have a place on the cyl. head to mount their axles, and I like moving, rotating objects on my engines!     8)



Over on the other side of the camshafts, a convenient place for the distributor.

Wadda you mean, "It don't run"???

Offline Longboy

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Re: LONGBOY'S "WEDGE RUNNER" MODEL ENGINE!
« Reply #12 on: November 25, 2020, 07:22:22 PM »
The rear deck plate is some thinner 3/16 in. material. Looking at both maintaining the inclined rake of the cylinder deck or a parallel mounting with the table surface.



I go with the cyl. deck match.



Looking to put a cooling fan on WEDGE RUNNER. I start with a bulkhead connector cut and trimmed to the shape I need.



Looks like I'll have about 2/3rds. of the fan exposed to airflow across the radiators.



Wadda you mean, "It don't run"???