Lawrence Merlin V12

[ddmckee54]

"I had to look up VWPBL ..."

Don't feel bad about that Andy, I had to look it up too.

 

[peterl95124]

I'm at the stage where at CM10 spark plug is about as small as I want to get.

I had to look up VWPBL ...

there's no such thing as a "born machinist" (like there are born musicians, etc), we all got there the hard way, trial and error, all it takes is patience and dedication, if you have those you will succeed and be rewarded !!!

 

[Bentwings]

yes, my spark plugs are made, 8-40 threads, you might be able to get away with 10-40 for a slightly thicker insulator, I might try if I had to do it over again, but things are really tight in the heads, larger plugs will interfere with the intake and exhaust components

while Barry Hares succeeded in making working scale magnetos that's way too impossible for me, I made my magnetos empty shells for scale looks, my actual coils and distributors are large enough to be practical to build and deliver a strong spark without worry of flash over between distributor parts, they are mounted behind the firewall of the display mount, here's a view from the rear, Sage-Geddy electronic ignition, moped coils, and 2" distributors (clear acrylic aids in setting timing!), one system per cylinder bank. real aircraft engines always have two spark plugs per cylinder, and mine does to be scale, but I only fire one per cylinder as that allows 6 outputs per distributor whereas 12 puts the parts too close together and I suspect flash over would be inevitable (I might make a 12 output 2" dist just to prove/disprove that some day)

I wouldn’t go wit h operating magnetos . Whether they would even work is problematic . Wimpy purchase a 12 cyl electronic ignition from C&H ignitions and be done with it.