Demon V8

[raveney]

Michael, Awesome work and thank you for posting the setups and details.

Have you considered using a dab of lapping compound to deburr the gear set?

I made a full set for this engine out of brass and they held up okay. I had to pin the bevel gear to the distributor shaft though, as the tiny set screw would slip while running even with Loctite. My water pump gears didn't come out too well.

Cheers!

 

[michael-au]

Michael, Awesome work and thank you for posting the setups and details.

Have you considered using a dab of lapping compound to deburr the gear set?

I made a full set for this engine out of brass and they held up okay. I had to pin the bevel gear to the distributor shaft though, as the tiny set screw would slip while running even with Loctite. My water pump gears didn't come out too well.

Cheers!

HI raveney
I did think of putting some past on the gears and see if it smooths them out, they don't need much

I'm thinking there is something like 1/2º of backlash in my 4th axis, its never shown up in anything else I have done in the 4th but gears might be a bit different
I Like your Demon the bell housing looks good too with the extra ribs on it

 

[michael-au]

Taking a break from the V8 and working on a Single Cylinder for a while

Build log here: Thompson Engine

 

[michael-au]

Slowly getting back to the Demon V8
made a start on the block, first I squared up the block of aluminium, then machined it to the correct size

Next was to drill the 1/8” holes that pass through to the Water jackets around the cylinders,
these holes have to be drilled from both sides because the drill is not long enough to reach all the way through
I first used a normal length drill, drilling all the way to the length of the flutes, the swapping to the longer drill
Using the shorter drill first gives a nice long pilot hole for the longer drill to follo the block was the flipped over and drilled to join up with the other holes
Drilling the second side only required the short drill

 

[michael-au]

Started to machine the block, drilling the holes for the bores and cam followers, for the left and right banks

 

[michael-au]

Machining the top of the block




Milling the bottom of the block

 

[michael-au]

Machining stock to the profile shape of the inlet manifold




Drilling holes for the inlet channels



Setting the vice to 5deg to drill the cross holes

 

[Steamchick]

Massive amounts of swarf produced! Great stuff!
Keep it up!
K2

 

[Eccentric]

Awesome, thanks for all of the great pics. I feel I am right there in the shop.

 

[michael-au]

Progress on the Demon has been a bit slow, I have been working on a 3 cylinder radial as well, I will put a build log up about the radial soon

This is a few of the parts I have made for the radial

 

[michael-au]

Finally back to the Demon
Made a new air cleaner for the twin carb setup

 

[michael-au]

Finished the Bell housing

 

[michael-au]

One of the most stressful parts is complete, the crankshaft














After cutting each journal I placed a disc of aluminium in the slot to stop the shaft from flexing

The ends were then cut off and turned to the correct length



One end of the crank was threaded




these are the discs that were in between the journals



Finished crank

 

[michael-au]

Finished Crank No. 2, The first one came out really good except I found out I machined the rod journals in the wrong order DOH

Anyway the second one is finished now so I can move on

 

[gbritnell]

Just change the camshaft to match the journals. (Different firing order)

 

[Peter Twissell]

I know that process! I made 3 cams for my Whittle V8 before I got one right. I also made 2 crankshafts for my boxer twin, but that was due to over-revving and twisting the first one.

 

[michael-au]

Got the flywheel done

 

[michael-au]

Turned up the blank for the camshaft and made the fixture for machining the cam

 

[michael-au]

My Mother had a fall and Broke her hip a week before christmas at 89 its a slow recovery, she is in rehab now
So most of my time is looking out for her not much time in the shop at the moment

 

[stevehuckss396]

Just a suggestion but when you cut your camshaft set aside a day where you have absolutely nothing going on and you can take your time and do the entire thing in one day. Walking away for lunch is no big deal but walking away for a day or 2 can cause problems, at least for me. Trying to pick up where I leave off isn't as easy as it sounds. If I remember correctly it took me about 5 hours start to finish but I was "in the groove" so allow 8 hours and stop for a snack every couple hours and it will fly right by. This and the crankshaft are the 2 things that were mentally taxing. Both were fundamentally easy but required a huge amount of concentration.