rivets versus screws in mast/boom

[DaveC426913]

I'm looking to install some hardware - lazy jacks, single-line reefing. The lazy jack kit I have comes with some rivets.

Are rivets significantly better than screws? Does it matter?

(Somewhere I read a trick to avoid snagging internal lines on screws: install the screw, remove it, nip the end off and reinstall.)

[restless]

nipping an end off a ss screw and then smoothing back the tread is a boring job. I put my spinaker track on with screws, and will soon be installing similar gear to you, ie. lazies n reefing bits. I'm not sure....... the only thing with screws.. you're talking self tappers here aren't you? I always tap (especially in grp) a machine screw in.

As I was saying, getting 6 - 20 tapped holes in perfect alingment is quite a skill in itself. Praps rivets are the way to go. Make sure you put your isolating gunge between your dissimilar metals.

If I had internal lines I would never use self tapers.. even nipped they will in time shred that horridly expensive string!

[bscott]

I've used alum rivets for years--never a problem--so far

Bob

[Hardcrab]

I won't argue if it's a valid comparison or not, but sheet metal screws are never used in aircraft construction.

Solid rivets and "Cherry" rivets, (much like the standard hardware store pop rivet) are what holds airplanes together keeping the parts from falling on our heads.

I go with pop rivets of the correct material and grip length, even though our Macs won't fall out of the sky and into an elementary school somewhere---

[Divecoz]

Rivets for Sure......... Crap gun $8 or the one that came with a cheap harbor freight kit..( throw it where it belongs , in the garbage right next to all those cheap sta-con crimpers!!!) A Good Pop Rivet Gun maybe $20 and its a Much Better tool..
Proper length.. Proper diameter... Proper base material. IMHO if your not working on wood to wood ( or wood to concrete) There are few places, Make That, dang few places, where screws are a proper / desirable fastening device.. Even fewer places on your boat or anybodies boat..

[DaveC426913]

My sailor friend pointed out that a riveter is dirt cheap. Like a pair of pliers. I assumed it was a gun, like with a compressor.

I had no idea riveters were dirt cheap, manual contraptions.

[Paulieb]

You can get an air compressed pop rivet gun, but if you only have a few rivets, it's easier and cheaper to use the manual pop rivet gun.
You should try a couple test rivets before attaching to the boom and make sure the gun is working correctly.

Paulieb

[RobertB]

As far as the statement that airplanes are put together with pop rivets like we use, not in the factory I worked in. Cherry rivets yes, solid rivets yes, hollow tubular pop rivets never. Big difference in shear strength and pullout resistance.

[bartmac]

I'd think twice about using just alum rivets for anything vital....go for Monel rivets I've been told ...expensive but ultra strong...also used in the aircraft industry

[snotnosetommy]

Having been screwed so many different ways in the past, I kinda like screws. I will note, however, that every single mast or boom-mounted piece of hardware I have purchased from BWY (the "mac experts") has been shipped with aluminum pop rivets. Also, most of the original hardware on my mac was popped on, including the spreaders.

[Crikey]

With the little I've done so far I've only used SS screws on the mast and boom. Huge learning curve! Wanting to make sure everything stayed tight I started with too small a hole (not by very much) and tried to walk in the threads. What I learned very quickly was that smaller stainless wasn't that strong and usually snapped if you tried too hard.
The only recourse to that was to try to grab what still stuck out with vise grips, and back it out. Trying to drill it out was near impossible, and if the grips couldn't do the job then it was the punch's turn which left a bigger hole needing a bigger screw (bugger!).

My next efforts will involve better quality rivets - you can drill them out, dont strip threads or screwdriver holes and are nice and flush. The remainder of your day can be spent drinking grog instead of swearing!

Ross

[Hardcrab]

RobertB,
If you were to re-read my post, I don't think I said that cheap aluminum pop rivets are used in aircraft.
I did mention Cherry rivets, which, as you know, work on the same model as pop rivets, but are far higher in strength and the amount of "pop" required to clinch.

I apologize if my wording was mis-leading.

[Divecoz]

OK GUYS..... #1 IIRC Cherry.. is ONLY a brand name and has a company web site JSYK.. That stated.. I dont doubt they are the standard in the industry .. ( Often copied seldom duplicated?) Just like Klein's and Channel-locks were among others for my industry..
2ndly we are talking Lazy Jacks.. Not Motor Mounts..

[Blue Max]

I used aluminum rivets on my mast to hold on a fitting for the boom vang. They pulled out at a bad time. Still I use aluminum rivets for lots of other things that don't have 400lbs pulling on them. Rivets would be my first choice unless the thing will be under a lot of stress, otherwise, machine screws.

[c130king]

I will soon be starting some projects to include 2nd Mast Hound for Spinnaker plus new & improved Lazy Jack rigging and hardware. So I will be installing things to the mast and the boom. And I think I am convinced that I will go with Pop Rivets. And you guys have some good info in this thread.

However, I havent' seen any specific recommendations for brands of rivet guns and rivets and size of rivets.

Having never even seen a rivet gun or rivets (that weren't already installed the skin/fuselage of the C-130's I used to fly) can anyone tell me what I need in terms of size of rivets and a recommendation on brand of gun/rivets?

Thanks,
Jim