Broken tap in mast

[boeing1]

never had luck drilling out a broken tap, and being up the mast is going to be difficult, using a dremel with small grinder might be the best solution, however doing this up the mast is still going to be a job. once out, re drill hole and go to next size.
good luck

[paulh]

highly unlikely any of that is going to work, but the goodnews is a rescue bit will probably drill out that broken off tap. It is a dimond cutting bit like nothing else. Not cheap, $45. Look it up on the internet.

[masonc]

Originally Posted by DeepFrz

You may have to use a very small hole saw. One that will just fit over the tap.

I like this idea

[oleman]

A broken tap in steel is bad, a broken small tap in aluminum is IMPOSSIBLE.
The aluminum galls around the flutes of the tap, an extractor of a #10 will not remove it. It will just break the drive pins.
The only real removal technique would be to remove the mast and take it to a shop with a milling machine and us a carbide drill and drill it out OR the shop could have an electric discharge machine that could remove it.
A common sense solution would be to drive it on threw and fish it out with a magnet or grind it off level with the surface and seal it from the weather.
Forget attempting to use the carbide bit in a hand drill you will immediately break the bit.

[a64pilot]

Originally Posted by Guy

Well he did say it was a #10, it's broken off down in the hole and he tried pliers. You all have see the flutes in a #10 tap?, Pretty small for or any needle nose pliers.

Then go for the hemostats, err roach clip for some

[Jim Cate]

Originally Posted by oleman

A broken tap in steel is bad, a broken small tap in aluminum is IMPOSSIBLE.
The aluminum galls around the flutes of the tap, an extractor of a #10 will not remove it. It will just break the drive pins.
The only real removal technique would be to remove the mast and take it to a shop with a milling machine and us a carbide drill and drill it out OR the shop could have an electric discharge machine that could remove it.
A common sense solution would be to drive it on threw and fish it out with a magnet or grind it off level with the surface and seal it from the weather.
Forget attempting to use the carbide bit in a hand drill you will immediately break the bit.

IMO, this is the first sensible post in the thread! If the tap was bogged down enough to break off, none of the extraction methods are likely to work unscrewing it. Driving it through may well distort the thin wall of the mast tube, and the idea of free hand grinding it out without damaging the mast is pretty optimistic! The hole saw method might work if one's hand is steady enough and the saw is available, but it leaves a bigger hole than might be desirable.

On the other hand, leaving it there, broken off flush or below the surface of the mast has little downside. Can't snag halyard or sail on the outside, some chance of interference on the inside if the tap protrudes far enough (unknown at this time). If rusting is a worry, squirting some silicone or other sealant through will fix that.

I do like the idea of putting the mast in a milling machine... but some difficulty in accomplishing this might be encountered!

So, good luck to the OP, hope that a good outcome is realized.

Jim

[nautitrix]

I have had hardened steel break off in aluminum and used a diamond bit on a Dremel tool to grind it out. In that instance the minimal damage to the aluminum around the hole was such that when I drilled to put a Helicoil in the hole it was the perfect fit. I have never used a diamond bit but remember that if you don't nail the tap directly, the aluminum around it is extremely soft. Helicoil is an inexpensive repair.

[Wotname]

Originally Posted by DeepFrz

You may have to use a very small hole saw. One that will just fit over the tap.

Or just cut away the Al around the broken tap and then repair the resultant hole in the mast. With a bit of preplanning, you will even be able to have the steel debris fall outside rather than inside the mast.

[Don C L]

Well I'll be one of the outliers here. I'd be inclined to leave it there, with some kind of sealant like silicone, unless it may cause chafe on internal halyards, then, yes, it must go.

[model 10]

I think this is where the mast is going to break off and the whole rig comes down in a storm.
So if this were an airplane spar, you would remove the broken tap by what ever means that works, but you would not leave the parts and shavings in the bottom of the mast either. Then you would ream the hole to fresh metal, in this case 1/4"and fill it with a rivet. If the reason you were trying to drill the hole in the first place was to mount something, then go 1/4". With a 1/4" fastener you should use 1/4-28 not 1/4-20. 3 complete threads min.

[sazarac]

Originally Posted by gaucho

I have a #10 tap that broke (half) inside the mast. I have been unable to remove it. It is high up in the mast, below the second spreaders.

Long story short; I sent the wrong person to do the job.

Now we tried pliers, we tried drilling (titanium drill bit) and achieved ... nothing really. It is just smoothed out, but probably 1/8 of the way to actually drill into it.

Suggestions?

Should I just forget about it, put some silicon there and let it meld together steel and aluminum and just forget it's there?

Im open to whatever experience dictates.

Google: Rockler screw extractor, might work if you are gentle.

[davil]

I believe you have a Passport 40?
that es substantial mast!!
so you drilled a hole about 3/16 in diameter?
I bet you have bigger holes as exits for wires,halyards etc.
hard to see that little hole is going to make your mast brake at that point.
Also,you were to install something and screw in a #10 screw?
if so,well now you have like a screw in there.
I personally have left screws and rivets could not remove on smaller masts.
What I normally done is to smooth the outside surface with a small grinder,dremel what ever works and perhaps use some epoxy like filler,the name escapes ,comes in a white packaging and enjoy cruising,next time in the boatyard have somebody go up
and remove it
My 2 cents and not one more whort it!!!

[ramblinrod]

Nothing a centre punch and club hammer won't fix with an aiming tap and the a whack. Seriously, don't waste time and effort in a bosuns chair, punch, club
Hammer, gone in 1/2 second.

[evm1024]

ditto on the punch, drill the hole to get rid of any ragged stress points (assuming that there are any.

Then JB weld or marine tex to fill the hole and retap with a #10. This assumes that this is not a high stress fitting placement.

Fish out the tap at the bottom of the mast with that magnetor with a vacuum (reducer to small side hose)

[Bluebeard]

As an experienced bodger, forget about anything that requires a steady hand whilst working from a bosuns chair.
A small hole cutter is the neatest option, though maybe not possible from a bosuns chair.
So I would use a Dremel or similar with a grinding tip or diamond cutter. Messy, slow and crude, but it will work even if it is difficult to keep perfectly steady.
As for the debris find the lowest accessible halyard exit slot, make a disc, that fits the inside of the mast, out of stiff but foldable plastic, and feed it into the mast. Let it unfold and fill the mast and support it somehow.
Yes very fiddly but I can't think of any other way of catching the broken tap, and it is at deck level.

As a life time professional structural engineer, don't worry about the extra hole you have created, it is smaller than any of the halyard slots so will not affect the structural strength of the mast.

Good luck I don't envy you