Should I drill more holes in the mast?

[Ziggler]

I'm upgrading spreader brackets for mast (not optional, the old system was deadly). As you can see in the pictures there're 3 existing, but now unusable holes in the upper (i.e. right side of these pictures) area from the previous bracket system. There's also a fourth, existing hole I was able to use to attached the lower part of the bracket and the shroud tangs.

Question: At what point does the structural integrity of the mast become compromised with too many holes? Won't yet more holes weaken mast where, I assume, it needs to be strongest (at the spreaders)?

- Of the two upper bracket holes (the two built into the spreader brackets in the last pictures that are above and below each other) could just drill one and not put a bolt in the other?

- Is there a non-bolt (non-hole) means of securing the bracket in place?

- Should I stop worrying, realize I'm not sailing around the world, just in rivers and inland waters and drill both holes?

P.S. This is for a 1979 Paceship 23. However, the mast is not original to this boat and I'm stuck with these new brackets.

 

[shemandr]

So long as they aren't swept back spreaders (so the upper shrouds are the backstay), the lowers don't terminate at the spreaders area and you don't bend the mast a lot, I think you are OK there.
In a straight spreader the loads are relatively modest.

 

[DianaOfBurlington]

Fill the holes.

Holes left unfilled are not good. Filling them with anything that will share the same sort of modulus will be much better.

I removed all the hardware from the spar in preparation to paint it. Here is how I resolved the problem:
http://dianaofburlington.blogspot.com/2012/08/removing-holes-from-aluminum-spars.html

Check it out.

You might see Dwyer Aluminum Mast Co (DAMCo) for replacement spreader brackets. They're terrific people and have lots of good parts for very good prices. Tell 'em I sent you.

 

[Crazy Dave Condon]

I second Cherubini's advice but on a smaller mast it really depends. I was as a former dealer hired to go up a mast to replace a wind vane. I never really looked at masts but went up in a bosun's chair. Mast failed and bent underneath the spreader bars. I landed several slips over and thru the mercies of God, I was not killed. Yes I was taken to the horsepital but nothing broken but was sore like heck. Customer demanded I replace that mast. The two of us inspected the mast together. When I saw a lot of holes drilled into the mast under the spreader bars, I asked who had done that as there was no question, it was unsafe. Mr. Owner who did not know much about sailboats replaced the spreader bars. He told his young teenager to reinstall the new spreader bar attachments. The young boy drilled too many holes. Mr. Owner paid for a new mast and my services to put it up.

After that, I always carried binoculars and inspected all masts whether large or small if going aloft.

The doc at the emergency room wanted me to stay overnight for observation but I said no. When filling out for pain prescritions, I said no as I had my own. When asked, I said I had my own peach brandy moonshine which I helped make chased with Mydol.

 

[GeorgiaBII]

Dave I'd swear the last time you told that story you bought him a new mast not the other way around....

 

[woodster]

The doc at the emergency room wanted me to stay overnight for observation but I said no. When filling out for pain prescritions, I said no as I had my own. When asked, I said I had my own peach brandy moonshine which I helped make chased with Mydol.

Dave i saw Barry Newman run a dodge charger into a couple of bulldozer blades drinking that kid of cocktail

 

[Geoff K]

Put a short screw back in the unused holes. It the screw head is in your way put the screw in with lock-tight and file off the head. The hole is a weak spot because it can distort/collapse. A screw in the hole prevents this.

Geoff

 

[Ziggler]

Thanks for the tips

All, thanks for the advice. I'm glad I asked as you've brought up considerations I'd not considered. Based on your collective wisdom it seems the preferred approach is to fill the holes with screws (heads on or removed). The specific steps are also very helpful, I read the blog link. I'll post an update on how it all goes. I was first alerted to this issue (of holes) in. "Good old boat", by Casey.