I need to fit the cowling on my plane - the engine head and carb needs an opening in the cowling which is made of fibreglass. I don't understand how will i cut these openings, and i am worried if i will end up breaking the cowling. Do i need special tools?

rc-iq

RC-IQ,

The best and probable the most tool used in the hobby is a Dremel tool. If you don't have one you need to get one. It makes everything much easier when building.
Mark out what you need to cut out and use the small cut off wheel and round grinder for the corners.

then take a dremmen sanding drum to clean up the edges. I take screen door spline split it with a hobby knife and glue it around the opening when i am done, looks very nice.

Originally Posted by DKnippen

RC-IQ,

The best and probable the most tool used in the hobby is a Dremel tool. If you don't have one you need to get one. It makes everything much easier when building.
Mark out what you need to cut out and use the small cut off wheel and round grinder for the corners.

This works great I used the dremel on my cowl for my 50% pitts cowl take a look!

dremel tool is the way to go.... has helped me many times in building.

I found this the easiest.......draw you cutout design on the cowl with a sharpie or waterbased marker...whatever will not hurt the paint.

Take a drill and drill small holes inside of your drawn line. once you have holes all the way around go back with the drill and connect the holes so the center of your design falls out. Next take your dremel with a round sanding wheel and sand to the drawn line. If you have a corner its best to round it vs make it square as a round corner is less prone to splitting.

Then take some rubbing alcohol and clean the cowl (if your paint is not affected by rubbing alcohol)

Rubber mallet

If you don't want to use a dremel, take an X-acto knife and carefully cut through each layer.(one at a time) you might have to CA it as the China built cowls are like crap.(air bubbles everywhere)


Hope this helps!
50%

Originally Posted by Highlights

Rubber mallet

Spoken like a true carpenter

If your first experience is anything like mine, don't beat yourself up: it's going to come out looking like hammered dog s#!t. I have tried making cardboard templates to copy onto the fiberglass cowl, but I always toss it and opt for my big hairy eye-ball. Remember, you cvan always cut more off, but it's very difficult to stretch fiberglass if you cut too much. Go a little at a time, and fit for clearance. Cut a little .... check .... cut alittle more ... check again. (Then, if you really want to follow my lead, order a new cowl )

As far as the right tool for the job: definately get a dremel or similar rotary cutting tool. That will give you the best chance for precision and neat cuts, as long as you don't let that cutting head go off on its own.

Dremel, respirator, goggles and baby powder.

What's the baby powder do?

Todd

Originally Posted by todhog

What's the baby powder do?

Todd

Load your exposed arms etc up with it and it helps keep the fiberglass dust out of your skin a bit.

or long sleeves work also