Removing steel bolts?


Enthusiastic about Wooden Canoes
Does anyone have any tips or tricks for removing siezed steel bolts that hold the seats and thwarts? At least I think they are steel. All of the brass fittings came off my canoe easily but these bolts are really stuck.
I have a hardwood gadget that I made for this purpose... works well. It's a piece of hardwood with a hole bored into it from one side, the diameter of which is just larger than the bolt head. Place this over the bold and hold it down with a clinching iron to add weight, and then use a ball-peen hammer from below to force the bolt up. Once the head of the bolt is up above the gunwale, you can screw the bolt out with a pair of vice grips. The value of the gadget is that it allows you to hammer the bolt up without splitting out the upper face of the gunwale.

PB Blaster

Rotti123 said:
Does anyone have any tips or tricks for removing siezed steel bolts that hold the seats and thwarts? At least I think they are steel. All of the brass fittings came off my canoe easily but these bolts are really stuck.

If the nut is seized to the bolt go to the auto supply/ Wal-mart/ someplace like that, and buy a can of PB Blaster. It is a spray to free seized steel bolts and stuff. Spray it on the nut and bolt junction in the morning when you get going, and after dinner at night for a few days. It should unscrew with only human, as opposed to super-human, force. I've used it on cars for years, and wouldn't think of removing rusted, corroded fasteners without it. It's magical.
Oh yeah, I forgot about the nut! Although a compound like this or maybe WD-40 can loosen the rusted nut, trying to remove the nut is probably just going to cause the entire bolt to turn in the hole. Even if it is a fin-necked bolt such as an Old Town diamond-head bolt, the decay of the steel leads to decay of the wood around it. So... treat the nut/bolt, and then grab the end of the bolt with vice grips, turn the nut down enough to get some space beteween the gunwale and nut, and then use a hacksaw to but of the bolt shaft (because grabbing the threads with the vice grips will damage the threads such that the nut won't completely come off).

The rusted steel will likely discolor the wood around it. While you might not get all of this discoloration out, particularly with some species of wood, treat the affected area with a concentrated solution of oxalic acid in water. This will do the best possible job of removing iron stains.

WD-40 ain't nothin' like PB Blaster . The difference is like lemon juice compared to 2 molar Nitric Acid. This stuff loosens bolts exposed to years of Michigan's winter roads. If the wood has grabbed the bolt, as it usually does, you shouldn't need a hack saw.

We use PB to take the large nuts and bolts off of coke oven doors. It's the only thing that works, it saves us from burning these nuts and bolts off the door - Republic Steel Corp. / Cleveland, OH

WD-40 stands for Water Displacement, 40th formula. The inventor was attempting to concoct a formula to prevent corrosion, by displacing the standing water that promotes it. In the process, he arrived at a successful formula on his 40th attempt.

WD-40's main ingredients, according to U.S. Material Safety Data Sheet information, are:

* 50%: Stoddard solvent (i.e., mineral spirits -- somewhat similar to kerosene)
* 25%: Liquefied petroleum gas (presumably as a propellant; carbon dioxide is now used instead to reduce WD-40's considerable flammability)
* 15+%: Mineral oil (light lubricating oil)
* 10-%: Inert ingredients
Sounds like I need to try PB Blaster, though I haven't seen it for sale in my area. In any case, the MSDS sheets for PB Blaster AND WD-40 show that they are both composed of organic hydrocarbons as their active ingredients. Maybe those in PB work better on rusted parts than those in WD, I don't know. But Rotti, the bottom line is that- however you do it- remove the nut and the get the bolt out. I've taken many rusted bolts out of gunwales, and in my experience they are too siezed in the wood or the heads are too deep to get them out from the top. On the other hand, they are rarely so siezed that they won't turn in the hole, especially in spruce rails. Don't worry, though- you'll get them out. Just take it easy to avoid damaging the gunwales if you intend to save them.

The nuts came off. I used WD40. Some loosened off and some just broke off while trying to turn them. But the bolts are still very stuck in the hole. I think I'll make up something to protect the rail as suggested and hammer them a little harder.
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One trick I learned (from a very skilled antique furniture repair man) to loosen screws (could be a bolt, nail or...) that have rusted into wood is as follows.

Drill a hole in a 2x4" (or there abouts) piece of 1/8th +/- inch metal (Aluminim works) plate the size of the screw head. Place this over the spot where the fastener is so the head is visible in the hole. Then with a mini torch, a jewelers torch or a small propane torch used by pastry chefs works best, direct the flame through the hole to heat up the screw. The metal protects the wood around the screw from getting scorched. It then backs out just like butter. Don't let it get too hot. Go slow and experiment at first, you will find the correct temp. The heat seems to make the rust release it's grip and allows the piece to come out easily.

I have a couple pieces of metal that I have found in second hand shops, with holes already drilled and have used this trick for stuck bolts, nails and screws.

Might not be what's needed here but you might like to file the info away for future reference, it works great.