Firewall work and finishing oil cooler duct: 7 hours

• More firewall planning and marking
• Drilled firewall for mounting brake fluid reservoir
• Drilled holes and fitted cable pass through's for the oil cooler airflow control and the engine alternate air intake control
• Prepped, primed and painted oil cooler duct with Rustoleum high temperature paint

More detailed marking of firewall items and penetrations:

Drilled for brake fluid reservoir:

Control cable pass through's for oil cooler airflow and engine alternate air intake:

Oil cooler elbow painted with high temp paint:

Oil cooler duct and firewall: 8 hours

The following items were done over multiple days...

• Did more sanding, filling and epoxy coating of oil cooler duct
• Used flox mixture to get a better fit between oil cooler duct and oil cooler flanges
• Drilled oil cooler duct for AN3 bolts also spent a fair amount of time carving out space for bolt heads on duct
• Worked on planning location of firewall items and penetrations
• Made copper bus bars to tie ANL fuses and battery / starter contactors together

ANL fuse holders and contactors:

Oil cooler duct with clear epoxy:

Filling gaps with flox:

Oil cooler duct and firewall layout: 4 hours

• Coated oil cooler elbow duct with micro epoxy mix.
• Did initial sanding on duct. This duct will be not be seen by anyone except during maintenance but I'm spending the extra time finishing it to practice my fiberglass technique.
• I also spent a good bit of time refining the layout of firewall items and organizing the new steel fittings I ordered for the firewall.

After sanding with 80 grit:

Initial micro layer: