Best way to cut hull for exhaust tips

[disco_charger]

Hey kids, I got a 3.5" exhaust tip, and I want to go to 4" (already bought the tips). What's the best way to cut the new hole?

[miller19j]

I used a router for mine. I made a template that was the size of the hole I wanted to open up to and got a straight cut bit with a bearing on the end. Clamped the template in place on the inside of the transom and adjusted the router so the bearing rode on the template and cut away.

[Schiada76]

disco_charger:
Hey kids, I got a 3.5" exhaust tip, and I want to go to 4" (already bought the tips). What's the best way to cut the new hole? Cut a piece of plywood same size as existing hole make sure it's a tight fit. Tap in place and use a hole saw. Worked for me. Give it a slight bevel and they tap in easy.
We all like a tight fit don't we?

[beached 1]

Go to K&H metals in Riverside. They sell any size cutter with arbor to make the hole you need that will fit your drill. Just need to figure out where you want to make the hole and set the arbor in the center.

[flat broke]

discocharger/rogers,
Assuming you went with a 4" tip, we have what you need. Call Tyson and maybe he can arrange to get it to you.
Talk to you later,
Chris

[Thunderbutt]

disco_charger:
Hey kids, I got a 3.5" exhaust tip, and I want to go to 4" (already bought the tips). What's the best way to cut the new hole? What is your reason for going to 4 inch? Do you have a big motor with a lot of horse power? with headers?

[Schiada76]

beached 1:
Go to K&H metals in Riverside. They sell any size cutter with arbor to make the hole you need that will fit your drill. Just need to figure out where you want to make the hole and set the arbor in the center. The holes are there, I think he needs a plug to catch the arbor, or if he usees a router he needs to make a template that he can clamp to the transom. :D :D

[RiverToysJas]

disco_charger:
Hey kids, I got a 3.5" exhaust tip, and I want to go to 4" (already bought the tips). What's the best way to cut the new hole? http://a1072.g.akamai.net/f/1072/2062/1d/gallery.rei.com/regularimages/404003.jpg
RTJas :D

[Froggystyle]

I like the idea of a template and using it for a guide. What I do on retrofits is draw the circle, and cut the fiberglass with a pneumatic recip saw I have with a metal blade. Cooks though it like a samurai sword. Very clean too.

[future boater]

Froggystyle:
I like the idea of a template and using it for a guide. What I do on retrofits is draw the circle, and cut the fiberglass with a pneumatic recip saw I have with a metal blade. Cooks though it like a samurai sword. Very clean too. what about a hole saw? and should you tape both sides of what your cutting to avoid splitting as with wood?

[Thunderbutt]

future boater:
Froggystyle:
I like the idea of a template and using it for a guide. What I do on retrofits is draw the circle, and cut the fiberglass with a pneumatic recip saw I have with a metal blade. Cooks though it like a samurai sword. Very clean too.
what about a hole saw? and should you tape both sides of what your cutting to avoid splitting as with wood? The hole saw will be hard to hold on a existing hole. Use the sawsall. The metal blade (fine teeth) will keep the glass and wood from splintering.

[Schiada76]

Don't use a sawzall! It'll wander and you won't get a perfect hole. Cut the plywood plugs with a jigsaw and the holesaw works great, or use the template/router method. The holesaw I used didn't spall anything on the inside at all either. You want a nice tight fit in the transom. :D

[Hotcrusader76]

BradP:
Don't use a sawzall! It'll wander and you won't get a perfect hole. Cut the plywood plugs with a jigsaw and the holesaw works great, or use the template/router method. The holesaw I used didn't spall anything on the inside at all either. You want a nice tight fit in the transom. :D Brad....I should have some pics for you tomorrow afternoon. Stay tuned...
~Ty

[future boater]

so the main thing is to use something with fine teeth to eliminate the splintering. i guess what has the fine teeth is all in how much you trust yourself.

[Jordy]

Damn, I guess I can't suggest using a dull chainsaw. You did say it was your friends boat right? :D

[Thunderbutt]

Make sure you tell us how it turned out and what you used. Why don't you call a boat builder and tell them what you want to do. Let us know

[BOBALOO]

heres what i did . screw a piece of wood inside the transom over the holes,it doesnt have to be round,then use a regular hole saw.looked bitchen w/new 4" rex stainless tips until they got that nasty white buildup on them.i hate to polish,almost should have left the orig bells on.good luck

[Rexone]

Mount anything inside the hole or across it (inside) for a guide for the pilot drill and use a 4" holesaw. Tape the transom first so it doesn't chip the gel coat. BradP's idea looks like what I'd use. Router will work too but maybe more work. I would use RTJas method as only a last resort before listing in the boat trader. :)