rivit replacement

[MaddysDaddy]

hey guys, i need to remove then reinstall some rivets in my hull. they secure the benchs and livewell to the side of the boat. they are all above the waterline. i must remove all the boxes and bench to replace the floor(i would have to use very small pieces and slide under if they stay). i have been tryin to find a good thread on the subject but i get too many hits.

can some one post a link, thanks

 

[sschefer]

Re: rivit replacement

I just drilled them out then replaced them with the same size stainless bolts and nyloc nuts. Mine have been there for two years and theres no problem. You can replace them with new rivets and buck them with a impact chisle cut off and concaved to fit the rivet and a backer block. You can get rivets and 18-8 stainless hardware at Fastenal or West Marine. Don't use the stuff they sell at Home Depot it's junk.

 

[andyrmilwaukee]

Re: rivit replacement

I just did exactly what you are talking about to my old alumacraft. Wanted to pull the seats so i could clean off all the old paint and get a good seal on the seams with gluvit. I drilled out the old ones and was able to find solid aluminum rivits at granger. They usualy only sell b to b but was able to talk them into selling to me. I did not have any special tools just a sledge hammer that i used to hold the rivit on one side and a peening hammer that i used to pound them, they do not have the perfect factory look but to me looks better than a bunch of bolts that seem out of place. The stanless bolts will work well too, just a personal choice! and I would not dare compare my level of experence to the person above.

 

[Haffiman]

Re: rivit replacement

I get the chill whenever I see recommendations of SST bolts and nuts, nylon washers or not, in an alu boats!!
Alu rivets, even if not 'looking' professional is the professional way of doing it.
An alternative is to use Monel rivets as used by riggers in masts and rigs.
SST might 'work' for some time in fresh water, but as a general recommendation, no!

 

[Yacht Dr.]

Re: rivit replacement

Stainless and alum dont like each other .. It will create electrolysis and eat the alum.

YD.

 

[andyrmilwaukee]

Re: rivit replacement

I thought stainless was pretty much ok with aluminum? Not as good as aluminum on aluminum

 

[Haffiman]

Re: rivit replacement

I thought stainless was pretty much ok with aluminum? Not as good as aluminum on aluminum

Add some salt water and you have a battery going.
Google: galvanic corrosion and go to Wikipedia.

 

[sschefer]

Re: rivit replacement

I thought stainless was pretty much ok with aluminum? Not as good as aluminum on aluminum

It is and works just fine. In a saltwater environment they are the prefered but you must use quailty stainless, 18-8 or better. I prefer to use stainless fastners anywhere I run into repeatable problems such as having to remove deck boards, etc.

I'm sorry but I have to just laugh at some of these responses. I spent 23 years in the Navy and just one of my specialties was elimination of HF interference on ship's. On the Aluminum super structured ships we used stainless and zinc based anti-sieze as the tried and true solution when bonding. Go figure.

Granted this is not a ship at sea we are talking about in this thread but my own personal experience is that the stainless steel fastners do not cause a problem in either Alkali lakes or saltwater bay's. My boat has been in San Francisco Bay on numerous occasions and I have no problems.

You are welcome to cast off experience if you wish.

 

[Yacht Dr.]

Re: rivit replacement

I agree..with special SS hardware and coatings you should be ok ( I have seen many SS fasteners with washers and special zinc coatings on them that would help on the corrosion ) ..

But you would have to agree that SS and alum would eventually fail..

""Corrosion is always a problem in a saltwater environment, particularly when you mix antagonistic materials such as aluminum and stainless or stainless"

Read up

http://www.bosunsupplies.com/Corrosion.cfm

I have been restoring/repairing for some time now.. and I allways had problems with spars or other ( windshields etc ) mounts that mix these metals .. Fusing is the biggest problem were the heads will snap off of the screw/bolt .. ohh.. that is not fun when a 1hr removal turns out to be 4 hours of extracting .. refil/glass and remount..

YD.

PS. Not trying to start another posting war just give info..

 

[sschefer]

Re: rivit replacement

I agree..with special SS hardware and coatings you should be ok ( I have seen many SS fasteners with washers and special zinc coatings on them that would help on the corrosion ) ..

But you would have to agree that SS and alum would eventually fail..

""Corrosion is always a problem in a saltwater environment, particularly when you mix antagonistic materials such as aluminum and stainless or stainless"

Read up

http://www.bosunsupplies.com/Corrosion.cfm

I have been restoring/repairing for some time now.. and I allways had problems with spars or other ( windshields etc ) mounts that mix these metals .. Fusing is the biggest problem were the heads will snap off of the screw/bolt .. ohh.. that is not fun when a 1hr removal turns out to be 4 hours of extracting .. refil/glass and remount..

YD.

PS. Not trying to start another posting war just give info..

Agree, I think that if you look at the owners manuals for most of these manufactured boats there are specific instructions when using the boat in salt water and some even go as far as to say do not use in salt water.

I could explain all that but not much point.

 

[MaddysDaddy]

Re: rivit replacement

thanks guys i think i will go with the alum. rivits. rather then bolts and nuts. sounds like something i can handle. how much does an impact cost? im guessing i have least 100 rivits and would like it to look as clean as posible so i would rather not do it by hand

 

[sschefer]

Re: rivit replacement

I would just buy a cheap one at Harbor Freight. Make sure your air compressor can produce the CFM needed.

http://www.harborfreight.com/catalogsearch/result?category=&q=Air+Chisel

On this page, if it displays correctly you'll find air chisels and a riveting hammer. Notice the price difference?

If you're doing this on the cheap then just by the air chisel. Cut the tip of one of the included chisles and grind a cup on the end. A piece of 1/2" or better steel backer block (buck) is the only other thing you need.

Depending upon the distance from outside to inside you may need to enlist a helper to hold the backer block. I have a couple of them made up that I welded extension rods on and bent for various angles.

If you plan to re-buck all the rivets then go with the riveting hammer. It's not a bad idea to go ahead and do them all if the opportunity is there.

 

[MaddysDaddy]

Re: rivit replacement

thats not to bad, 100 bucks for the gun. i am always looking for a reason to buy tools anyway. are there differnt grades of rivits or ar they all the same?