Spade Bit for Cutting Hole?

[bcbouy]

its so thin it wont have time to heat up or bind before you cut thru it.

 

[fish4thriLLs]

Thanks to all for the info. I think I will go with a hole saw. It probably will be one made for cutting wood, so I will go at it very slowly to insure a clean cut.

 

[Ranchero50]

For the cleanest cut with a hole saw hold the drill at an angle so only part of the teeth are engaged at one time. As the saw cuts through the metal change the angle so the teeth are pulling through the metal vs. pushing through the metal. If you hold it square you tend to end up with a bigger hole because the thin aluminum will wallow out arond the center drill.

That's why I recommend a unitbit for smaller holes.

Jamie

 

[Butthead]

I used a cheap Black and Decker wood hole saw to cut the holes for my seat mount. Cut through the aluminum with ease.

 

[fish4thriLLs]

Okay, a work buddy of mine loaned me a hole saw with a couple of "blades" with it, the smallest of which is 1.25" dia. My thru-hull fitting measures 1.0" dia. Would it be okay to go ahead and use this or will the hole be too big for it to work alright? I think it will be okay, but I've never done this before so I don't know for sure how much difference, a 1/4" too large of a hole, will make.

 

[Captain Ahab]

Okay, a work buddy of mine loaned me a hole saw with a couple of "blades" with it, the smallest of which is 1.25" dia. My thru-hull fitting measures 1.0" dia. Would it be okay to go ahead and use this or will the hole be too big for it to work alright? I think it will be okay, but I've never done this before so I don't know for sure how much difference, a 1/4" too large of a hole, will make.

Try it on a piece of scrap plywood or even cardboard

 

[bcbouy]

your thruhull fitting should give you a little room for error, about 1/4 ",incase the bit wobbles a little.don't forget to seal the fitting before tightening.

 

[Ranchero50]

Okay, a work buddy of mine loaned me a hole saw with a couple of "blades" with it, the smallest of which is 1.25" dia. My thru-hull fitting measures 1.0" dia. Would it be okay to go ahead and use this or will the hole be too big for it to work alright? I think it will be okay, but I've never done this before so I don't know for sure how much difference, a 1/4" too large of a hole, will make.

In a word, no. You'll have a 1-3/16 hole when you use it, you throughhull won't fit well and will look like crap. If anything drill small and open it up with a round file. Mark the diameter with a quarter and open it up from there...

You only have to do it right once... #-o

 

[Jonboat Jerry]

For the cleanest cut with a hole saw hold the drill at an angle so only part of the teeth are engaged at one time. As the saw cuts through the metal change the angle so the teeth are pulling through the metal vs. pushing through the metal. If you hold it square you tend to end up with a bigger hole because the thin aluminum will wallow out arond the center drill.
That's why I recommend a unitbit for smaller holes.
Jamie

X2 And get a DEATH GRIP ON THAT DRILL when using a hole saw! If that sucker hooks up on what you are drilling, it will take the drill right out of your hands! (experience)

 

[devilmutt]

I cut mine on the smaller side, then used a sanding drum in the cordless drill to open it up a bit.

 

[fish4thriLLs]

Just finished with the outlet hole a little while ago. Worked great. My bilge pump is now installed.

Thanks everyone for your help and comments. You all rock!

 

[Skidz]

Looks good!

 

[fender66]

Perfect!