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I hesitate to post this cuz it demonstrates my abject lack of knowledge.. anyhoooo.

I'm putting a reefing line on my C&C 30. The boom has a block mounted in the appropriate spot just aft of the leech but I'll need to mount a turning block on the luff end to run the line to the base of the mast and into the cockpit.

Relative to the size of the screw, what size pilot holes do I want to drill?
Also, does one have to use a tap to create threads or just push and screw harder till it goes in :p

Thanks,
Beej
 

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I have a C&C 30 (Redwing) and added reefing cheek blocks as well. SVTatia is correct, drill and tap. I found that SS 10x32 bolts tapped and coated with Tef gel (I use Lanocoat) is easy enough. Saw last week they have the taps at Home Depot.

Why not dispense with the turning blocks on the forward end of the boom? If your main hayard is at the mast, it's easier to just hook a reef cringle on a reefing hook. nis approach also reduces the amount of line friction over a single-line reefing approach.
 

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Over Hill Sailing Club
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Definitely drill and tap as described. When you drill, make sure to mark your hole locations and center punch before trying to drill. Even better, get the first hole tapped and then mount the block with the first machine screw, clamp it and drill and tap through the last three holes with the block in place. Drill the diagonal hole second. It can be tricky, trying to drill on a rounded surface and drilling the holes before you mount the block could well result in the holes being misplaced. Put a stop on your drill bit so you don't drill through something inside the boom.
 
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I hesitate to post this cuz it demonstrates my abject lack of knowledge.. anyhoooo.

I'm putting a reefing line on my C&C 30. The boom has a block mounted in the appropriate spot just aft of the leech but I'll need to mount a turning block on the luff end to run the line to the base of the mast and into the cockpit.

Relative to the size of the screw, what size pilot holes do I want to drill?
Also, does one have to use a tap to create threads or just push and screw harder till it goes in :p

Thanks,
Beej
For my 2nd reef, I did something similar without drilling any holes at all.

I have long shackle connecting my gooseneck to my tack. It prevents the sail from pulling aft when tensioning the outhaul. I just got a Ronstan Series 30 block with a shackle, and hung it off the long shackle.

 
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When drilling a hole to tap do your homework and be sure you are using the correct sized bit for the threads you intend to tap. I've discovered that the ideal bit size is often given in wireguage that may not correspond to a english or metric bit. (home depot does not carry wire guage bits)

The difference may seem miniscule but remember that aluminum is relatively soft, the stainless screw is hard and you don't want ANY play between the two.
 

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Over Hill Sailing Club
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The correct way to tap ANY metal is to back the tap out often, use oil, and don't try to muscle through. Aluminum is very easy to strip so great care must be taken when getting the tap started. Go until you first feel the threads start to grab and back off, go a LITTLE bit more and back off again. Backing off clears the threads. Until you have a couple of solid threads in, and it's obvious that you are making clean threads, don't dare over-torque or you'll strip the threads right out, eventually winding up with a stripped out hole. Easy-does-it.

I really like s.s. rivets. I bought a heavy duty pop rivet tool and often use rivets. I don't think they are as secure as well threaded holes in thick enough metal but if you're trying to tap aluminum that's less than 1/4" thick, there just aren't many threads in the tapped hole.
 
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I've had generally bad luck tapping aluminum. In time, the screws seem to always tear out the threads. Instead, I've been using SS rivets. I'd be curious for any thoughts on this.
...

I really like s.s. rivets. I bought a heavy duty pop rivet tool and often use rivets. I don't think they are as secure as well threaded holes in thick enough metal but if you're trying to tap aluminum that's less than 1/4" thick, there just aren't many threads in the tapped hole.
This seems to be logical to me in my situation. I have to add many things to my boom but it is on a small boom with far from 1/4'' thick alum. So, stainless rivets were my question. Seems like a much more secure solution. Do you do anything to isolate the SS from the Alum on the rivets?
 

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The only time I tapped aluminum was to mount mast gates. In that application, the screws did not have much stress on them. But if they ever strip or corrode, I would need to re-drill in exactly the same place - I can't move the mast gate somewhere else. For that installation, I downsized the holes (and screws), so I could get a "second chance" to re-tap later with a larger hole/screw.

I use thread lock for the threads to minimize metal-to-metal contact, and also lay down a polyethylene sheet between the SS mast gate and the mast. So far, no corrosion - but I'm in a fresh water environment.
 
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Over Hill Sailing Club
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I attached some of my mast steps with 1/4" rivets. A gun like this:http://http://www.amazon.com/Astro-Pneumatic-4-Inch-Heavy-Duty-Riveter/dp/B00061SFDM/ref=pd_cp_hi_1 is needed for large rivets. A small pop rivet gun will be circular file material pretty quickly. As far as coating them, I'm not really sure it makes any difference but you can use any number of products. I usually use Penetrox if anything at all, mainly because I have it left over from electrical jobs. For threads, I always use a thread lock product like Loctite if I want it to stay put, never-seez:Bostik Marine Grade Products - Industrial Supply Group if I want it to later be removable. Never-Seez should be std. equip. on any boat:)
 
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There are dozens of "tap and drill size" charts online.
I have never used the tef-gel, but I do use a neverseize product specifically made for alloy instead of steel. It works for years on ss in alloy (I do all my outboards with it and I never need heat or penetratants to work on them) and it's available at any auto parts store, usually gold instead of gray colored.
 
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The threaded hole that secures my mast gate is the thing that causes me the most trouble. It seems to instantly seize and then strip the next time I need to remove the screw. I've re-tapped it several times and I'm now at the point where the next size up would bee to big, so I'm considering installing a threaded insert. So far though, I haven't found them in Stainless Steel. If anyone has ever seen them in stainless, I'd love to know the source.
 

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Over Hill Sailing Club
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The threaded hole that secures my mast gate is the thing that causes me the most trouble. It seems to instantly seize and then strip the next time I need to remove the screw. I've re-tapped it several times and I'm now at the point where the next size up would bee to big, so I'm considering installing a threaded insert. So far though, I haven't found them in Stainless Steel. If anyone has ever seen them in stainless, I'd love to know the source.
If you can't find s.s., maybe make your own. Cut off a fine thread bolt of a larger size, center punch it and drill/tap it back to the original size. You could also just weld it over and re-drill/tap. Spalling of s.s. threads is a PITA, one of the negative qualities of s.s. It seems as soon as the threads get even slightly deformed, they jam up and eventually strip out.
 

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The threaded hole that secures my mast gate is the thing that causes me the most trouble. It seems to instantly seize and then strip the next time I need to remove the screw. I've re-tapped it several times and I'm now at the point where the next size up would bee to big, so I'm considering installing a threaded insert. So far though, I haven't found them in Stainless Steel. If anyone has ever seen them in stainless, I'd love to know the source.
They do make aluminum or nylon screws, but they are soft. Since this is not a high-stress application, an Al or nylon screw might have less corrosion - if you have room to try one more tap.
 

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If I understood this correctly, the OP is intending to put a turning block at the mast end of the boom so that he can lead the bitter end of the reefing line to the cockpit.

How you attach the block seems like a moot point to me. I wonder why one would want to lead the reefing line to the cockpit. You will be up at the mast securing the cringle on the gooseneck anyway (translation for lingo: securing the new lower corner of the reefed sail to the mast end of the boom), so why not leave the reefing line there. On a small boat, it saves valuable space in the cockpit which would otherwise be cluttered with another line end, and on a bigger boat it eliminates friction at multiple turning blocks needed to lead the line aft.
 

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This seems to be logical to me in my situation. I have to add many things to my boom but it is on a small boom with far from 1/4'' thick alum. So, stainless rivets were my question. Seems like a much more secure solution. Do you do anything to isolate the SS from the Alum on the rivets?
I've had generally bad luck tapping aluminum. In time, the screws seem to always tear out the threads. Instead, I've been using SS rivets. I'd be curious for any thoughts on this.
If you use monel pop rivets instead of SS, you'd have no corrosion problems.

The threaded hole that secures my mast gate is the thing that causes me the most trouble. It seems to instantly seize and then strip the next time I need to remove the screw. I've re-tapped it several times and I'm now at the point where the next size up would bee to big, so I'm considering installing a threaded insert. So far though, I haven't found them in Stainless Steel. If anyone has ever seen them in stainless, I'd love to know the source.
I believe (no expert here) the reason you'll not find SS threaded insert is due to the steel properties. SS is much harder than aluminium to form the lip that would secure the insert.
But since aluminium ones are available, its just a matter of coating the threads with Tef-Gel or similar. This way you have a secured screw that is protected from corrosion.

If I understood this correctly, the OP is intending to put a turning block at the mast end of the boom so that he can lead the bitter end of the reefing line to the cockpit.

How you attach the block seems like a moot point to me. I wonder why one would want to lead the reefing line to the cockpit. You will be up at the mast securing the cringle on the gooseneck anyway (translation for lingo: securing the new lower corner of the reefed sail to the mast end of the boom), so why not leave the reefing line there. On a small boat, it saves valuable space in the cockpit which would otherwise be cluttered with another line end, and on a bigger boat it eliminates friction at multiple turning blocks needed to lead the line aft.
I totally agree. Leading lines to the cockpit may be misleading (pardon the punch) -- you may believe that its going to be easier, but since you have to go to the mast anyway, it may not be. Save the work until you have enough experience to determine the best approach.
 

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Im a huge fan of hooks for the tack...simple and if maintained well it eliminates yet another line

those single reefing systems are anything but simple or effective....

all lines at the mast....on big boat best thing you can do is have those stainless pulpits or whatever they are called...love them for helping you keep in place, tying things and supprting you while near the mast...

dont like the whole lines led aft dealyos...think they do more harm than good especially on small boats where a step or 2 has you at the boom and mast ready for action...

oh the only thing I like having aft is a jib downhaul...not needed on many boats but I singlehanded a 26 footer a lot that had a nice jib downhaul that could be used in the cockpit...that way I could dock under main sail power alone most of the time
 

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...I'm putting a reefing line on my C&C 30. The boom has a block mounted in the appropriate spot just aft of the leech but I'll need to mount a turning block on the luff end to run the line to the base of the mast and into the cockpit..j
Congratulations on selecting a beautiful boat. I've always considered my fondly-remembered C&C 30 the best instance amongst my boat ownerships. Enjoy.

I expect the main halyard does not come back to the cockpit, and that there is no line led aft for the reefing tack. If you do not have both these in place, you need to go to the mast anyway to reef, so skip the idea of running the reef inf line aft, and just use the standard cleat installed forward on the boom to secure your reef. There should be two, one for each of the two standard reefs.
 
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