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0

Whatever length wrench you're using, choke up on the handle all the way. "Too tight" begins once you start deforming the washer. Once you do start to deform the washer, you have to toss the, "hand tighten, then 1/4 turn with a wrench," out the window (not that I've ever found that sentiment to be satisfactory). I've never cracked a toilet by over ...


3

Those are screw caps, to prevent nasty people from tampering with the cylinder. They are generally removed by drilling them out.


2

My grandfather was a master plumber for more than 50 years. I asked him one time how tight to make a sink faucet shutoff valve connection. His answer is a classic ... "Tight enough so it don't leak". There is a lot of wisdom in this. The answer for the toilet is the same thing, not too tight but tight enough.


1

I think there are multiple factors that contribute to this effect but I think one has not been mentioned. One other way to get a stuck bolt to release is to shock it by hitting it sharply. Generally this is something you do something large like a valve but I think the underlying problem is the same. For rust, I would expect that this can shatter the ...


2

@Vladimir Cravero (sorry not enough rep to enter a comment)... I think clarification of the answer is needed. The nut isn't expanding "more", it ends up larger but the % increase is the same. r = 1.5*(1+500*10-5) mm = 1.5075 mm R = 1.501*(1+500*10-5) mm = 1.508505 mm start after heat increase amt % inc bolt 1.5 ...


58

The answer is surprisingly simple: the bolt expands, but the nut expands more. What is happening here is good old thermal expansion: The bolt is heated and expands outwards, its radius increasing The nut is heated and... expands outwards, its radius increasing Now, since the nut's radius is slightly greater than the bolt's, and since the increase is ...


1

In my experience, you have to heat a frozen bolt until it is blistering, red hot and getting soft, and remove it while it is hot and soft. Heating the bolt and allowing it to cool has never helped me. As the metal contracts, the bolt seizes; it usually doesn't loosen... it probably makes the situation worse. The same is true for drinking glasses that have ...


27

The actual reason this usually works is that rust is significantly larger than the steel it's rusted from, which is why the bolt is stuck in the first place. In some other instances the reason heat works is that the bolt was applied with a threadlocker that requires heating to remove (if it comes out with no sign of rust, that's a pretty good bet) Many ...


11

Metal arranged in a ring expands outward when heated. Imagine a ring of thin wire being heated--it expands primarily along its length, making both the inner and outer diameters larger. The same occurs with the material around a bolt hole. Generally, I try to heat the surrounding piece and not the bolt itself. However, even if the bolt is heated directly, ...


29

The secret is constrained expansion. Here's some cruddy diagrams to help explain how it works. Bolt stuck in a hole When the bolt is heated, it expands. Since the shaft of the bolt is constrained, it can't expand inside the hole. The bolt expands in the direction of the green arrow, but cannot expand in the direction of the red arrows. As the bolt ...


3

Yes. 8 high-quality gold or stainless (not black oxide) construction screws (two at each connection point) with at least 1-1/2" penetration will hold with more than enough strength for even a typical adult. In this case, use 3" or 3-1/2". Torx are much nicer to work with than Phillips. Pre-drill 3/4 of the screw's length and the diameter of the screw ...



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