I have a fiberglass center console and need to cut a 4" hole on the inside of the side of the boat (not cutting thru the outside of the side of the boat).

I bought a panel to cover the hole once it is cut, but my 4" hole saw drill is too small and the 5" hole saw drill is too big to fit the given template on the panel door.

So my question....is a jig saw the best way to make the cut? If so what type of blade is best to not chew up my boat?

Or is a rotary tool (Dremel)?

Thanks.

tape the area with painter's tape and use jig saw and get at it. I like the course blade to get a faster cut since you are gonna put a panel over it.

I would have to drink a lot to cut a 4" hole

I cringe at adding screw holes

I agree Fish Killer...For some reason in the starboard side of my transom, my Pathfinder has a secondary panel on the inside that flairs out from the actual transom. I need to get my hand in there to install a power pole (to get to the bolts that will be installed on the transom intself).

Any other thoughts?

If you want it fairly precise, mark the circle you need and use your 4" hole saw that is too small. Then go get you a set of those sander drums that are designed to be chucked into a drill. You'll use quite a few of them, but they're cheap and you can just about get it spot on. I've done it a few times and found it was better chucked into the electric drill rather than the battery drill, but both worked. Also, don't forget your gloves and respirator!

*edit*
You mentioned a rotary tool, which would be the same basic idea. Use your small 4" hole saw to take out the bulk and then use a sanding drum to expand outwards.

Can you not mount it between the motor and transom or with a jackplate bracket?

I use a roto-zip. Works like a charm.

I thought about hooking up the pole to the jackplate, but I'd have to buy the $200 arm and either remove the entire motor to attache the arm to the backside of the jackplate or drill holes into the jackplate and attach it that way.

So I thought the best/easiest way is to attach directly to transom since I have the room.

cutting holes in a perfectly good boat is never a good idea when you can bolt it to the jackplate good luck.

Even going between the jackplate and motor it's an hour job to mount it
With the side mount. It's quicker than that

Good point all....you may have convinced me to go with the jack plate mount....Can you give me any pointers on drilling into the plate? I forget the jack plate brand, but I'm fairly certain it did not have any mounting holes pre-drilled?

Thanks again.

Cut a hole in the deck of my Ranger to install a recessed foot control. Took me awhile to get up the nerve but I did and glad I did best investment in my back I ever made.Used a diamond jig saw blade, cut through the deck like butter. But I agree with everyone else don't mount the power pole on the transom get a bracket installed on the jackplate.

You guys are just too paranoid. drill it, cut it , seal it up and it should be fine.

use a roto zip, its depth can be adjusted

Honestly. If you don't have one that can be mounted to the side of the jackplate. I would probably use the in between plate and shim before I tried to drill and tap it

Just back off the mounting holes on each side till you have enough room then do one side at a time and tighten them back up

Hardest thing you will have to do is decide where to mount the pump