Dalton Engine Baffleing

[WOODisGOOD]

I am doing some Baffling on a 42% Aerotech extra so I thought I would do a thread on it.
You first want to have your engine mounted as well as your cowling before you start. Put some Vaseline at the front where the top half meets the bottom so they will not get glued together. And save all the Vaseline jokes I have allready heard them.

[WOODisGOOD]

Next you will need a foam block.You can ask your kit supplier and most time they will have scraps and will be more than happy to send you some with your kit. Cut the block alittle oversize to fit inside the cowl. Sand and shape as needed so that it fits snug with no gaps . You dont want to force it into position as this will put a twist in the cowl once its glassed in.

[WOODisGOOD]

Heres the block by itself

[WOODisGOOD]

I use a product called Great Stuff to glue the block in place. You can get this at Home Depot. Put a small bead around the inside of the cowl as shown.

[WOODisGOOD]

Use some light weights to hold the block into position while the foam sets up. Put some wax paper on the floor and set the cowl on top or your cowling will get stuck to the floor.

[WOODisGOOD]

After the foam is dry you will need to cut a ruff opening. I use o long serated knife to do this.

[WOODisGOOD]

Depending on how your cowling is mounted you need to find a way to slip the cowling on and off but have it in its proper location each time. I take the 2 top mounting bolts that go through the cowl ring and screw them in from the inside.

[WOODisGOOD]

Next you will need to cut the back of the block to the cylinders. Remove small amounts at a time and keep checking the fit as you go

[WOODisGOOD]

Once you are satisfied with the fit start shapeing the foam. I use some aluminum tubeing with sand paper glued to it for shapeing. Again remove small amounts and check the fit. Also try to sand the foam as smooth as possible. The smoother you can get the foam the smoother your glass will be.

[WOODisGOOD]

The shapeing is complete and its ready for fiber glass. I will post more pics of the fiberglass part later today.

[BDSBob]

Looks great! What landmarks on the cylinder do you use to determine the correct size/shape of the opening around the cylinders?

Thanks-
BDSBob

[WOODisGOOD]

I dont have a set size. I simply try to get every bit of air that comes into the front of the cowl to go over the cylinders. I have done this on many different planes some with 2 openings like a edge or Velox and have never had overheating problems.