Drilling aluminum hull

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fishinnut99
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Drilling aluminum hull

Post by fishinnut99 »

Want to add a thru hull fitting for an automatic bilge pump. Needs a 1 inch hole. What's the best bit to make a nice , neat hole? Thanks

overboard
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Drilling aluminum hull

Post by overboard »

I used a hole saw, drill a pilot hole first.

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LDUBS
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Drilling aluminum hull

Post by LDUBS »

overboard wrote:I used a hole saw, drill a pilot hole first.
+1 on the hole saw. Last time I drilled a 1" hole in steel I used a Bosch bi-metal hole saw. Worked good for me. Another option would be a step bit. Might get a little pricey for 1" capacity.
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nccatfisher
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Drilling aluminum hull

Post by nccatfisher »

Unibit

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beetlespin
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Drilling aluminum hull

Post by beetlespin »

nccatfisher wrote:Unibit
Ditto

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WALI4VR
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Drilling aluminum hull

Post by WALI4VR »

Hole saw... Just DON'T use the hole saw below the water line,

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CedarRiverScooter
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Drilling aluminum hull

Post by CedarRiverScooter »

Run it slow to avoid it gumming up. I have also heard you can coat it with parrafin to avoid alum pickup in the teeth, although I haven't tried this myself.

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richg99
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Drilling aluminum hull

Post by richg99 »

I run my bilge exit lines OVER the transom. I know it isn't as effective, but it keeps me from drilling holes in my transom or sides.

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LDUBS
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Drilling aluminum hull

Post by LDUBS »

richg99 wrote:I run my bilge exit lines OVER the transom. I know it isn't as effective, but it keeps me from drilling holes in my transom or sides.

richg99
Huh, common sense and nothing to really go wrong. Might be more effective than you take credit for. I drape my transducer line over the transom because I don't want to drill thru the transom.
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DaleH
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Drilling aluminum hull

Post by DaleH »

Drilled a hole in the stern stem of my FRP boat for an in-hull xducer, 6" off centerline - hull was a 1" thick layup. Then drilled the bow deck for a custom pulpit and bollard - hull layup on the bow centerline was 4" thick! Boat was a Parker - dayum well made boats they were!

Now drilling holes in tin boats is easy peasey ... hole saws work for me! If the metal grabs, I'd chalk the bits, but I'm through the hull in seconds with the good ones that I use. As a former machinist (a real one, not an 'offset' button pusher one ...) I've seen more work butchered by unitbits. They may have a place with others, but not for me.

Bearclaw
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Drilling aluminum hull

Post by Bearclaw »

I'm with Dale on this one, I'd use the hole saw. Just be sure to use some sealant on the fitting to seal it off. If your hole isn't as neat as you want it you will never know it after the thru hull fitting is on.
Dale,you saying a CNC man isn't a real machinist? I'm a old handle turner too brother, but have a little of the button pusher to go along with it.
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nccatfisher
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Drilling aluminum hull

Post by nccatfisher »

I have seen just as many wallowed out with a hole saw with worn out teeth as with a unibit. As for keeping the material from building up in the teeth in a hole saw a squirt bottle with water always worked fine for me.

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RiverBottomOutdoors
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Drilling aluminum hull

Post by RiverBottomOutdoors »

Unibit makes the cleanest hole, but you don't need a pretty hole. The through hull is flanged and covers the hole. Drill hole, de-burr, silicon, install thru-hull.

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onthewater102
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Drilling aluminum hull

Post by onthewater102 »

Any reason why you wouldn't use a 1" spade bit?
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LDUBS
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Drilling aluminum hull

Post by LDUBS »

onthewater102 wrote:Any reason why you wouldn't use a 1" spade bit?
On Aluminum, the ones with the bat ears work fairly well, but I like the hole saw better.
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