Cannon Fodder from Bruce Finney

After installing a new prop I found that the old front spinner bulkhead would not fit. The old prop hub thickness 3.875" plus spacers to fit the 4.5" spinner spacing. The new prop hub is 4.62" thick. My spinner supplier would be more than happy to make a new front bulkhead but it would mean creating a new form at a cost of approximately $400 plus the cost of the bulkhead of $80. So in the true spirit of home building I made my own.

I used my CNC router to create a mold using pink insulation foam from the aviation department at Home Depot,

 Vacuum bagged Stretchelon bagging film into the form using a micro balloons slurry to glue it in place.

 

Laid up 5 layers of bi-directional fiberglass cloth

And vacuum bagged it.

Front bulkhead removed from the form.

After trimming the edge and fitting to the prop to match the mounting holes, the finished bulkhead ready to be installed on the airplane.

Test fit in the spinner and it fits fabulously.

Bruce Finney

N18JF T-18C #262
Auburn, WA  USA