hoglet build question

[Jamie Barton]

Hi,
Im currently boring the spark plug recess on my hoglet build. As the cut is at 30 degrees is the depth measurement on the drawing taken along the center of the hole or down the deepest side of the hole / recess? Its the first time Ive used a boring head and Im not enjoying it...

 

[neil_1821]

I’d say it’s taken to the center of the hole but I can’t fully remember, I can always measure it when I get home tonight. I’m sure someone else will come along with more information.

I think I used a slot drill when I did mine, it’s not fun and can be very easy to crack a fin, I scrapped one piece when I was boring the exhaust port.

 

[Jamie Barton]

If I crack one of mine Ill probably start again in aluminium instead. Ill have spark plugs soon so I can bore and try. Ive not cut cooling fins yet, thought it may be safest to do those last.