1/4" solid rivets...

[basenjib123]

I need to replace many rivets on the bottom of my 12ft. Can I just remove the old rivets, drill out the holes to 1/4" and use 1/4" solid rivets regardless of what is in there now?, I assume 3/16" in there now. Seems to me that just going to 1/4" holes eliminates the worry of screwing up the 3/16"? .. Can anyone recommend a decent quality 1/4" rivet bit for an air hammer? Thanks, Joe.

 

[DaleH]

I wouldn't ...

Take your time, use a new PRICK punch (60-degree included angle at the 'tip') to carefully hit the center of each rivet, then use a good 3/16" (cobalt preferred) bit to drill them out. Always keep the drill square to the surface being drilled. If the head stays on the hull, whack it off with a sharp chisel set at a low angle. One tip, mark the enter of each rivet with a fine point Sharpie marker so you know exactly where to 'hit'; also makes the work go faster!

See here for the special brazier head tool and a bucking bar: https://tinboats.net/forum/viewtopic.php?f=3&t=41248&p=419799

Now here's my 11-year re-riveting 'her' 12' boat using all of the tools and knowledge above, so if she can do it - then so can you : https://tinboats.net/forum/viewtopic.php?f=3&t=41042

Rivet, buy the 1100F alloy ones from Jay-Cee Rivets online, buy a little or buy in bulk!
https://www.rivetsonline.com/?gclid=CjwKCAiAudD_BRBXEiwAudakXyxt3Jjt_9H3VXODRQbrJSlLWJ_lDVj6xFFWzrODjOV1jYCyG1y2EBoCTS4QAvD_BwE

 

[basenjib123]

I wouldn't ...

Take your time, use a new PRICK punch (60-degree included angle at the 'tip') to carefully hit the center of each rivet, then use a good 3/16" (cobalt preferred) bit to drill them out. Always keep the drill square to the surface being drilled. If the head stays on the hull, whack it off with a sharp chisel set at a low angle. One tip, mark the enter of each rivet with a fine point Sharpie marker so you know exactly where to 'hit'; also makes the work go faster!

See here for the special brazier head tool and a bucking bar: https://tinboats.net/forum/viewtopic.php?f=3&t=41248&p=419799

Now here's my 11-year re-riveting 'her' 12' boat using all of the tools and knowledge above, so if she can do it - then so can you : https://tinboats.net/forum/viewtopic.php?f=3&t=41042

Rivet, buy the 1100F alloy ones from Jay-Cee Rivets online, buy a little or buy in bulk!
https://www.rivetsonline.com/?gclid=CjwKCAiAudD_BRBXEiwAudakXyxt3Jjt_9H3VXODRQbrJSlLWJ_lDVj6xFFWzrODjOV1jYCyG1y2EBoCTS4QAvD_BwE

Great info. Thank you very much!

 

[basenjib123]

One more question .. what do you do if/when you drill out a hole too big or out of round? Then go to a 1/4 rivet? Thanks again.

 

[DaleH]

One more question .. what do you do if/when you drill out a hole too big or out of round? Then go to a 1/4 rivet? Thanks again.

If slightly out-of-round the 3/16" will fill it. If wayyyyy out, then sure go larger. Using the prick punch technique I've never had to go larger nor reseal a newly bucked new rivet, nor those my youngest girl did ...

 

[basenjib123]

One more question .. what do you do if/when you drill out a hole too big or out of round? Then go to a 1/4 rivet? Thanks again.

If slightly out-of-round the 3/16" will fill it. If wayyyyy out, then sure go larger. Using the prick punch technique I've never had to go larger nor reseal a newly bucked new rivet, nor those my youngest girl did ...

Any sense of how long of a job it is to do say ... 70 rivets or so? Thanks.

 

[DaleH]

70 :shock: ?????? Uhhhhhhh ... are you sure you don't need a NEW hull .... ???????????????????

But I did > 300 in an afternoon once, but all the new pieces were already prepped, so that was just the install. Otherwise, I could only guesstimate really.

Remember you need a helper too - one on each side of the rivet. Need source of air, air hammer, rivet tooling, bucking bar, goop (if rivet hole is out of round) and EAR MUFFS for sure! Keep the punch, chisel and drill handy in case you need to replace one too.

 

[basenjib123]

70 :shock: ?????? Uhhhhhhh ... are you sure you don't need a NEW hull .... ???????????????????

But I did > 300 in an afternoon once, but all the new pieces were already prepped, so that was just the install. Otherwise, I could only guesstimate really.

Remember you need a helper too - one on each side of the rivet. Need source of air, air hammer, rivet tooling, bucking bar, goop (if rivet hole is out of round) and EAR MUFFS for sure! Keep the punch, chisel and drill handy in case you need to replace one too.

Well I was thinking about just doing them all on the bottom but I guess that is over kill huh? ..If I only do the ones that are leaking I guess its more like 10-12 .. hope you don't mind all the questions....you've been a great deal of help, thanks..Joe.

 

[DaleH]

If I only do the ones that are leaking I guess its more like 10-12.

What length? For that amount I might be able to spare a dozen ...

I also feel that for ones not leaking - if it’s not broken - don’t fix it!

... hope you don't mind all the questions....you've been a great deal of help, thanks..Joe.

You’re welcome Joe, as that’s the purpose of this website! So ask away ...

 

[Moxsam]

I need to replace many rivets on the bottom of my 12ft. Can I just remove the old rivets, drill out the holes to 1/4" and use 1/4" solid rivets regardless of what is in there now?, I assume 3/16" in there now. Seems to me that just going to 1/4" holes eliminates the worry of screwing up the 3/16"? .. Can anyone recommend a decent quality 1/4" rivet bit for an air hammer? Thanks, Joe.

Are you sure the original rivets are 3/16"? I would bet that they are 5/32". The original rivets will most likely be 5/32 made of 2117 (have a dimple in the middle of the head)

Start with a 5/32" drill bit (or #21) and drill just as deep as the rivet head. Stop and use a small cold chisel to knock the head off. Use a 5/32 pin punch to drive out the tail. You may possibly need someone holding a bucking bar or hammer beside the rivet tail on the other side. This is to prevent you from caving in the aluminum as you try to punch out the remaining tail.

Also an air hammer and a rivet gun are two different things. The stroke (or throw) of an air hammer is very short and it doesn't hit very hard. A rivet gun (especially a bigger one) will have a longer stroke and hit harder. Using an air hammer to drive 2117 solid rivets will work harden the rivet and they may not compress at all. If they are 1100 series you may get away with an air hammer.

Use rivets made of 2117 for anything that requires structural strength. 1100 series rivets are ok for filling a nasty hole and stopping a leak but they have very little strength.

Be careful just randomly moving up to a larger size rivet. The larger rivets will take away from your edge distance.

If you want to learn about riveting the Standard Aircraft Handbook has a ton of good info.

https://www.amazon.com/Standard-Aircraft-Handbook-5-e/dp/0071576428

 

[basenjib123]

Well I am a bit embarrassed to say that I'm not really sure you to determine what size rivets that I have. The Boat is a 1951ish 12 ft. Duratech...if that helps? Thanks, Joe.

 

[508]

$11 will get you a caliper from Amazon (https://www.amazon.com/dp/B07DFFYCXS/ref=cm_sw_r_cp_apa_glt_fabc_T6WFZGBSM7XMJAYFRZCG?psc=1) and you can make a guess based on the size of the mushroomed side of your existing rivets or measure the hole from one you've removed.

 

[DaleH]

Contrary to what another poster opined ... so I'll just 'agree to disagree' with them.

Size: I've yet to see any size other than 3/16" solid rivets used in any of the dozens of tin boats I've re-riveted for myself or for anyone else.

Alloys for Rivets: Well, I replaced entirely new transom skins inside and outside of the stern, and I called Starcraft. Andy, their Customer Service tech, told me to specifically use 1100F rivets, as 1000 series rivets are 'softer' than the 5000 series alloy that the hull is made of.

This is a well-known engineering practice in the design and construction of riveted items, where you want the rivet to be softer as THEY are the wear/stress-'replaceable' item ... whereas the hull is NOT.

In use over time, you'd want to replace a rivet ... not the hull tin panels.

 

[508]

Contrary to what another poster opined ... so I'll just 'agree to disagree' with them.

Size: I've yet to see any size other than 3/16" solid rivets used in any of the dozens of tin boats I've re-riveted for myself or for anyone else.

Alloys for Rivets: Well, I replaced entirely new transom skins inside and outside of the stern, and I called Starcraft. Andy, their Customer Service tech, told me to specifically use 1100F rivets, as 1000 series rivets are 'softer' than the 5000 series alloy that the hull is made of.

This is a well-known engineering practice in the design and construction of riveted items, where you want the rivet to be softer as THEY are the wear/stress-'replaceable' item ... whereas the hull is NOT.

In use over time, you'd want to replace a rivet ... not the hull tin panels.

@DaleH I agree, and you gave a much more detailed reply than mine. I assumed my boat (early '90s Meyers Fisherman) used 3/16" but the original rivets were actually slightly smaller. It's a weird boat in a number of ways, though.

 

[pghgrouser]

For what it's worth my starcraft has 5/32 rivets on the side and 3/16 rivets on the bottom. Odd but verified with calipers on multiple rivets.

 

[lckstckn2smknbrls]

I agree with drilling out the head and chiseling off the head.

 

[basenjib123]

Thanks for all the replies, I got a lot to learn .. you guys are a big help, thanks..Joe.

 

[nytebyte]

I did not see it mentioned but I would try rebucking the rivets first. Might not need to replace any!

 

[Colorado1135]

what is the best length to get to replace them? I see 3/8" 1/2" what if they are too long? is it best to get a variety and use just the length you need or can they be pounded down?

 

[DaleH]

what is the best length to get to replace them? I see 3/8" 1/2" what if they are too long? is it best to get a variety and use just the length you need or can they be pounded down?

I probably used 3/8" 98% of the time, bought just a handful longer "just in case".

And NO, you cannot pound them down. Cut them or file them shorter? - yes. Pound? Uhhhh - no.