Another Internal Combustion Engine

Rdean33422 · Oct 19, 2024

I know the title is kind of vague but I really haven't made up my mind yet. I was thinking of a side shaft Hit Miss engine, or an overhead cam Hit miss engine , or a marriage of the two so I will just start and see what happens.

I haven't had a lot of shop time with 2 hurricanes and the cleanup afterwards. The tractor fan blade went through the radiator so I had to replace that and the wife keeps finding new projects for me to do but I'm going to start this anyway.
I have had these two weights around for some time and they are of no use like they are so why not make a couple of flywheels.

Now I have had good luck machining weights in the past to make flywheels but this time the outer part of the rim was very hard. Carbide inserts would just throw sparks and then give up. The sides machined OK but the rim was made from ???
I had to resort to the tool post grinder for a decent finish on the rim.

And the finished product. Two 5" flywheels with taper lock hubs.

It's a start.
Thanks for looking
Ray

Rdean33422 · Oct 20, 2024

I had started this crankshaft a couple of days ago. It has a 3" stroke.

It is assembled on a 12mm shaft with a loose fit and Loc-Tite 620. I used the lathe to hold everything in line over night.

This is after I installed tapered pins and cut out the middle section of the rod.
The shiny places are where I filed the pins smooth.

And painted and done.

Thanks for looking
Ray

Richard Hed · Oct 21, 2024

Rdean33422 said:
I had started this crankshaft a couple of days ago. It has a 3" stroke.
View attachment 160413

It is assembled on a 12mm shaft with a loose fit and Loc-Tite 620. I used the lathe to hold everything in line over night.
View attachment 160414

This is after I installed tapered pins and cut out the middle section of the rod.
The shiny places are where I filed the pins smooth.
View attachment 160415

And painted and done.
View attachment 160416

Thanks for looking
Ray

I've got a whole bunch of those weights that have flywheels inside.

Rdean33422 · Oct 21, 2024

Richard it seems to be a hit miss if you get one that will mill half way decent these were not good.

This aluminum is what is left over from my 6 cyl build.

It was too large in all dims so over to the band saw.
First a 1 1/2" wide slice over the width.

Then two cuts to remove the angled piece.
The setup looks dodgy but it worked just fine.

Right off the band saw.

And after truing up all sides.

Thanks for looking
Ray

kf2qd · Oct 22, 2024

I wonder if those weights are spin cast. That might cause some migration of heavier elements to the outside during the pour. Probably a lot of nickel in the rim of those castings.

Rdean33422 · Oct 22, 2024

I don't know but it sure was hard to machine.

I made a bunch of chips and I got rid of anything that didn't look like an engine base.
No end mills were harmed in this operation.

I really like the idea of a one piece engine base.
I may use this style more often.

I also cut out and installed the two main bearing caps.

Thanks for looking
Ray

Rdean33422 · Oct 23, 2024

Drilling the holes for the main bearings.

And finishing to size with a boring head.

I made a brass spacer to go between the bearing race and the crankshaft on each side to lock the crank in place.
(Sorry but you can't see them in this Picture)

(No not this picture either)

Maybe I shouldn't have mentioned them.

Thanks for looking
Ray

Sparky_SC · Oct 23, 2024

You make this look way too easy ! I can't believe how fast you build a engine and how nice the end results are.

Nerd1000 · Oct 24, 2024

kf2qd said:
I wonder if those weights are spin cast. That might cause some migration of heavier elements to the outside during the pour. Probably a lot of nickel in the rim of those castings.

Probably not spin cast, just the cheapest quickest sand casting they can do (gym weights just need to be heavy) If they used chills in the moulds the rims would be cooled quick enough to turn into white iron, which is very hard.

Be easy to anneal them if you have a fireplace.

Rdean33422 · Oct 24, 2024

Sparky_SC said:
You make this look way too easy ! I can't believe how fast you build a engine and how nice the end results are.

Well thank you Sparky that is very kind to say.

Nerd1000 said:
Be easy to anneal them if you have a fireplace.

I don't have a fire place or a burn barrel but I understand they have to be heated and then left in the ashes to cool slowly. Just how hot do they have to get?

Today
The cylinder block was cut to size and trued up all sides.

Over to the lathe to drill and bore for the cylinder liner.

Thanks for looking
Ray

Nerd1000 · Oct 24, 2024

Rdean33422 said:
Well thank you Sparky that is very kind to say.

I don't have a fire place or a burn barrel but I understand they have to be heated and then left in the ashes to cool slowly. Just how hot do they have to get?

Today
The cylinder block was cut to size and trued up all sides.
View attachment 160505
Over to the lathe to drill and bore for the cylinder liner.
View attachment 160506

Thanks for looking
Ray

I think hot enough to glow cherry red would do. But the cooling has to be slow.

GreenTwin · Oct 25, 2024

Some weights are not standard gray iron.
.

Jasonb · Oct 25, 2024

Bit more than cherry red, around 875-900deg C is bright red.

Rdean33422 · Oct 25, 2024

I think these are made of some mystery metal that was added for filler. I may just not use them anymore they are just not worth it.

Now another cavity cut 2 1/2" deep.
These aren't really that bad to do but there is a lot of handle turning and swarf to contend with.

The finished product.
Now to clean up the shop again.

The cylinder liner will be next.

Thanks for looking
Ray

Rdean33422 · Oct 26, 2024

I thought I had a cast iron rod large enough to make the liner from but I was wrong.
I did have a piece of steel rod that will work just fine.
Turned down to size with a larger lip on one end to fit a groove in the cylinder.

Cut off the waste in the band saw and faced the end to length.
Using different size drills and a boring bar the inside is turned to size.

The finished liner and cylinder.
Note the groove in the end of the cylinder for the liner to press against.

I use red form a gasket to seal the water jacket and around the liner.
The liners lip is longer than the groove in the cylinder is deep so I then place the liner and cylinder in the vise overnight to cure. I found out the hard way that when the form a gasket cures it will push the liner back out of the cylinder which doesn't show up until you try to start the engine.
When cured the liner and the cylinder face are surfaced in one operation.

Thanks for looking
Ray

a41capt · Oct 27, 2024

Looks great Ray, and nice tip on the form-a-gasket too. I’ve been considering a similar operation and wondered about the water seal around the liner.

Thanks!
John W

Rdean33422 · Oct 27, 2024

It not only seals the water jacket but I have never had a combustion gas leak either.

Here it is after decking the cylinder.

Thanks for looking
Ray

minh-thanh · Oct 27, 2024

Sparky_SC said:
You make this look way too easy ! I can't believe how fast you build a engine and how nice the end results are.

Exactly !

Rdean33422 · Oct 28, 2024

Thank you Minh but this build has me really thinking and planing.

I cutout the connecting rod today.

Right off the CNC machine.
This sucker is over 9" long.
I wonder if it will be strong enough for this engine.

Connecting rod with wrist pin ball bearing and 1.25 piston.

Well so far my measurements are working out and the crank shaft does turn.
I did have to taper the end of the liner for clearance.

The cylinder is not attached to the rails yet that's next.

Thanks for looking
Ray

Rdean33422 · Oct 30, 2024

I got the cylinder mounted on the side rails and the screw holes all lined up.
The cylinder is well aligned with the side rails and the crankshaft turns freely.

Made up a drawing for the camshaft supports.
Will cut them out later.

There won't be much room left between the engine block and the flywheel with the side shaft gears in there but I think it will all fit.

Thanks for looking
Ray

Another Internal Combustion Engine

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