Installing larger Seacocks, how to dril the larger hole

[Outlaw7]

Please post the source of the G10 Thanks

[mike_kelly]

myldon, I have seen that but I don't trust "gluing" the heads and not having them someday break loose and spin preventing me from removing the seacock.


Outlaw, https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[s/v Jedi]

I buy it here: https://www.jamestowndistributors.co...ct.do?pid=8758

[stormalong]

Originally Posted by mike_kelly

Stormalong, If the adhesive is what is holding the thruhull in why do you use a nut on the tailpiece vs the way Forespar does it?
.

Mostly because it holds it all together while the caulk cures - a very slow process unless you use fast cure caulk. Secondly because if you need to remove the seacock in the future you do not want to spin the tailpiece. If you spin the tailpiece you will have to take it all apart and re-caulk.

[mike_kelly]

Originally Posted by stormalong

Mostly because it holds it all together while the caulk cures - a very slow process unless you use fast cure caulk. Secondly because if you need to remove the seacock in the future you do not want to spin the tailpiece. If you spin the tailpiece you will have to take it all apart and re-caulk.

"Secondly because if you need to remove the seacock in the future" Now that is a bad dream...



I'll have to think about that. I guess while the 5200 is setting up you don't really want to torque on the thru hull, spinning on the seacock, or it is going to squeeze all the sealant out and spin the mushroom around. If you use the seacock to hold the thruhull in, it might get 5200 on it which is bad. Without the nut or the seacock to hold it the thru hull would drift out of the hole which would not be good either. Hmm


I guess I could cut a piece of wood and jam it in under the mushroom to the ground outside while it cures...



But when I was trying to get the old brass junk out the nuts would not release for anything. The new nut is going to get 5200 on it if you tighten it down when the sealant for the thru hull is setting.



It just dawned on me that you really can't use reversed bolts sticking up from under the pad because once the pad is glued down you then can't spin the seacock off without ripping the pad off.


Good things to think about before I start.

[GordMay]

Originally Posted by Outlaw7

Two hole saws, one the size of current hole and one the size of the hole you want. Put the large one on the arbor first then the smaller leaving it proud of the larger one by a quarter inch. Line up the holes that the two pins go through and tighten the lock nut. Place small hole saw in current hole and start slowly.

For around $15, there are hole enlarger kits (concentric hole saw arbor):

Bosch 2-Piece Hole Enlarger Kit #HE1
➥ https://www.boschtools.com/ca/en/bos...s-he1-33428-p/

Lee Valley "Oops" Arbor #30N03.90
➥ "Oops" Arbor - Lee Valley Tools

Disston “Blu-Mol” Hole Enlargement Arbor #5547 / E0102465
➥ https://disstontools.com/product/blu...hole-enlarger/

[mike_kelly]

Originally Posted by GordMay

For around $15, there are hole enlarger kits (concentric hole saw arbor):

Bosch 2-Piece Hole Enlarger Kit #HE1
➥ https://www.boschtools.com/ca/en/bos...s-he1-33428-p/

Lee Valley "Oops" Arbor #30N03.90
➥ "Oops" Arbor - Lee Valley Tools

Disston “Blu-Mol” Hole Enlargement Arbor #5547 / E0102465
➥ https://disstontools.com/product/blu...hole-enlarger/

Good to know, thanks

[hellosailor]

Mike-
If you do use a simple hole saw? A locksmith taught me that you can get a nice gentle clean bite with a hole saw by starting it IN REVERSE. That way the teeth don't bite and you don't scuff up someone's expensive door. Once you've got a new "circle" showing on the material, put it in forward and just make the hole, the blade will stay in that shallow track as it bites in.

[mike_kelly]

Great simple idea.

[s/v Jedi]

Going up 1/4” in size, does the smaller hole saw fit inside the larger (I don’t think mine do...)

[GordMay]

Step Drill Bits can be useful for smaller hole enlargements (usually max 1-3/8").

[mike_kelly]

Originally Posted by GordMay

Step Drill Bits can be useful for smaller hole enlargements (usually max 1-3/8").

That is what I used the get my old brass thru-hulls out but it is pretty wicked.

[mike_kelly]

Got my G-10 pad material and it looks good. So thanks again for all your suggestions.

[waterrat]

Originally Posted by s/v Jedi

Take a small scrap piece of plywood and drill it with the correct size holesaw. Now hold that piece over the spot you want to drill through the hull and use it to keep the holesaw steady until it has cut a bit into the fiberglass after which you don't need the guide anymore

Did you check the Compass Marine website on how to install this? Backing plate, 5200 etc...

If the existing thru-hull does not already have a backing plate, adding a backing plate could become the hole saw guide quoted above.
An alternative would be to cut a plug out of scrap plywood the size of the existing hole and put it on the center drill bit of the hole saw and use it as the guide to center the hole saw when drilling the larger hole. Maybe wrap tape around the plug to fit tighter in the existing hole. This is to fill the material removed by the hole saw teeth. Bung plugs are not cheap.
Also, if the hull is cored, be sure to remove coring around the new hole and fill with epoxy or fiberglass.

[lewisa]

Re: Groco questions. Call Groco with your questions. They have superb customer service with answers by real experts (not some telephone flunky). I replaced all my old rubber-gasketed Groco seacocks with new ones and the Groco rep was remarkably helpful, including advice on the best method to remove the old ones.