How many holes are too many-J/24 Mast

[jamesmalcolm 9]

I have some mast hardware that I need to move. The Genoa halyard cleats are too low and I am considering adding a lead block and cleat for the topping lift. This means six new holes drilled in a mast that already has a few old holes in it. Since they are all on the same 2 foot section, how many more can I add before I risk weakening the mast?

[shaggy 1,096]

35 minutes ago, jamesmalcolm said:

I have some mast hardware that I need to move. The Genoa halyard cleats are too low and I am considering adding a lead block and cleat for the topping lift. This means six new holes drilled in a mast that already has a few old holes in it. Since they are all on the same 2 foot section, how many more can I add before I risk weakening the mast?

Them Thar be speed holes in that fleet my friend...  Dollars to donuts most 24 masts have seen a ton more than 6 holes.  They prob add a few every time a boat is sold...  Gov??  LOL

[jamesmalcolm 9]

16 minutes ago, shaggy said:

Them Thar be speed holes in that fleet my friend...  Dollars to donuts most 24 masts have seen a ton more than 6 holes.  They prob add a few every time a boat is sold...  Gov??  LOL

another 6 it is then, except this time I'm not using a tap on the mast. 

[learningJ24 532]

Not sure how old your mast is but having dealt with a couple of cracked ones you should consider putting rivets in the old holes to increase support and plates (riveted) over any square holes left over from removing  internal sheave boxes.  Also, make sure you check the jib halyard exit box, if it's an old mast with twin halyard sheaves and was raced hard on triangles there could be cracks radiating from the corner of the sheave box. 

Why the hatred of threaded holes? I've found them to be easier to deal with than rivets using superglue as locktite.

[jamesmalcolm 9]

7 hours ago, learningJ24 said:

Not sure how old your mast is but having dealt with a couple of cracked ones you should consider putting rivets in the old holes to increase support and plates (riveted) over any square holes left over from removing  internal sheave boxes.  Also, make sure you check the jib halyard exit box, if it's an old mast with twin halyard sheaves and was raced hard on triangles there could be cracks radiating from the corner of the sheave box. 

Why the hatred of threaded holes? I've found them to be easier to deal with than rivets using superglue as locktite.

I have had 2 cleats with taps pull out of the mast. My main halyard cleat and 1 of 2 jib halyard cleats. Fortunately no sheave boxes or cracks in any of the holes. Will rivets prevent the old holes from cracking? If so I'll see about riveting them.

[learningJ24 532]

17 hours ago, jamesmalcolm said:

I have had 2 cleats with taps pull out of the mast. My main halyard cleat and 1 of 2 jib halyard cleats. Fortunately no sheave boxes or cracks in any of the holes. Will rivets prevent the old holes from cracking? If so I'll see about riveting them.

Rivets will support the area around the holes and help prevent cracks.  Cracks usually start near corners so plates over the rectangular holes help as well. I've found that 12-24 bolts work really well for the higher stress areas but that loosening is usually the issue.  Problems come in when I get lazy and don't loctite the bolts.  With the 12's you will sometimes need to drill out the cleat a bit but I've found no problems (yet) with the cleat coming apart.  For the main halyard, all my boats have been set up with a horn cleat. My rigging philosophy is to put on the simplest, lightest kit for the job, modified for crew happiness. I prefer clams for spin sheets but the crew wants clams so clams it is.