Rusted carriage bolts on swim platform

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Gilhooley

Veteran Member
Joined
Sep 21, 2014
Messages
70
Location
Greenland
Greetings,

I'm trying to pull some corroded SS carriage bolts out of my swim platform while its on the hard. They hold the platform to the brackets. The threads are really furry with 10 years of rust and while I've made the nut move with a mix of ATF/acetone, I need to to find some way for holding the bolt stationary while I back the nut off. Normally in metal... no problems. Fire or die-grinder or weld something on the top or whatever... working over head in delicate fiberglass seems to have removed all of my usual options. Any suggestions? I have about 8 of them to remove.

Gilhooley
 
Die grinder with cut-off blade. Cut the nuts off. Replace them with new bolts and nuts.

Time is money for many people.
 
Doesn't help with getting the SS bolts off, but when I had a similar problem on the Carver I replaced them with bronze bolts and nuts. Wasn't as astronomical as I thought, maybe $10 each, needed six as I recall. I was very, very careful not to drop them in the water though.
 
How good are you with a Dremel? You can replace with stainless machine screws/locknuts.
 
I agree here, grinders are real cheap and will make fast work of cutting them off, just make sure you are wearing safety glasses.
harborfreight.com

Die grinder with cut-off blade. Cut the nuts off. Replace them with new bolts and nuts.

Time is money for many people.
 
Doesn't help with getting the SS bolts off, but when I had a similar problem on the Carver I replaced them with bronze bolts and nuts. Wasn't as astronomical as I thought, maybe $10 each, needed six as I recall. I was very, very careful not to drop them in the water though.
Agree with the bronze...alternative would be the best stainless I could find...but it still will rust a bit and hard to find.
 
Good stainless is fine for the application; embed with TefGel and then spray with CorrosionX HD and all's well. I got my stainless carriage bolts for my platform refurb from McMaster Carr.
 
Thanks folks. I was against my traditional terrestrial methods because either my shop compressor is less than portable (die grinder) or the fasteners are right up against the glass (not good for fire). Ted's nut splitter sounds ideal and I have one that has travelled every dirt bike mile Ive ridden for 25 years. Getting old...... :)

G
 
The problem with even good stainless unless you have grades not easily obtained is that any caulking the eventually breaks down will allow aerobic corrosion of the stainless...and rust stains.
 
That is exactly what TefGel is designed to combat. After several years of heavy saltwater exposure I can testify it works.
 
Ok. if you want to believe that....tef gel will cause the same thing...lack of O2 to the stainless.

Unless chemistry has changed since I posted this or you can keep the bolts totally encased.

It is why stainless isn't recommended for underwater use...unless necessary for strength over bronze and the best alloys available.
 
Ok. if you want to believe that....tef gel will cause the same thing...lack of O2 to the stainless.

Unless chemistry has changed since I posted this or you can keep the bolts totally encased.

It is why stainless isn't recommended for underwater use...unless necessary for strength over bronze and the best alloys available.

Perhaps you should do a little research. You're wrong. I've actually tested it tested it in multiple rigorous conditions for extended years of time. And, they're right:
http://www.tefgel.com/contain.php?param=tefgel_infor
 
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I expect nothing less from the manufacturer.

I would like to see independent tests and explanation how they defy basic chemistry. Unless like I said you can manage to keep a perfect coating on a carriage bolt head on a swim platform.

Like you have posted before.....maybe this forum is more dangerous than we think...guess it depends on what side of the coin you are on.
 
I'm not sure that bronze hardware into a stainless bracket is a good idea either. I would go to McMasterCarr online and order 316 grade stainless. Most generic stainless hardware is 304 (18-8) grade, and yes it will rust eventually. As to removal, a grinder to the bottom, with cooling water applied to the fiberglass side would probably be my first choice, if accessibility were not an issue.
 
Bronze props on a stainless shaft....the swim platform if partially underwater should be zinc ed or bonded.
 
Try impact

Sometimes an impact tool will turn a nut right off even if the bolt spins a bit.
 
Take your Dremel or grinder and cut a slot in the bolt so you can put a large screwdriver in it to hold it while you undo the nuts.
 
Take your Dremel or grinder and cut a slot in the bolt so you can put a large screwdriver in it to hold it while you undo the nuts.

Yup! And, since the OP has already got a little movement on the nut, slight rotation back and forth - say 10 degrees, with plenty of penetrant. Stops the rust dust from binding in the threads.
 
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