76
votes
Accepted
If metal expands when heated, how does heating a bolt loosen it?
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
...
- 1,081
67
votes
How can I get a bolt with no head out of my wall?
This is a job for vise grips. What I would do is file the bolt flat on two sides. Don't take off so much that you significantly compromise its strength - just flatten the threads. These flat sides ...
- 8,752
49
votes
Accepted
How do I prevent the bolts in my snow blower rotor from breaking?
The "right kind of bolt" is a shear bolt.
Specifically, the shear bolt your snowblower manufacturer specifies for that location, since not all shear bolts are the same.
It is deliberately ...
- 202k
39
votes
How do I remove this bolt from my bedframe?
Looks like an IKEA bed to me - something like the MALM or the HEREFOSS.
You first remove the metal rail, then undo the nut. The manual depicts a wrench (ikea part 113453) but a regular metric 13mm ...
- 549
34
votes
If metal expands when heated, how does heating a bolt loosen it?
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 ...
- 131k
32
votes
How can I stop bolts from loosening over time?
The easiest way is to replace the nut with a Nylanut AKA Nyloc nut:
By Original uploader was Btarski at en.wikipedia. - Originally from en.wikipedia; description page is/was here., CC BY-SA 3.0, ...
- 12.6k
31
votes
Accepted
What is this attaching my toilet seat and how can I unscrew it?
That is called a blind jack nut, jack nut, blind collapsing nut, etc.
They are typically used when you don't have access to and/or don't have the tools to hold onto a nut on the backside of whatever ...
- 426
30
votes
Accepted
What is the right tool for old, rusty, flat cross head bolts?
Looking at the condition of the nut and the minimal profile of the head, I'm afraid the better question may be "how do I get these out with minimal damage to the wood?"
I'd take a drill to ...
- 27.9k
30
votes
How can I stop bolts from loosening over time?
Thread Lock Adhesive
You can use a thread locking compound, such as this.
- 401
27
votes
If metal expands when heated, how does heating a bolt loosen it?
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 ...
- 202k
26
votes
How can I get a bolt with no head out of my wall?
Say you try one of the other proposed approaches in the other answers and the screw is just stubborn and more of the shaft keeps snapping off...
Consider that you might not need to remove the screw at ...
- 5,227
25
votes
How can I stop bolts from loosening over time?
You can also find bolts with a locking nylon patch applied, like these from Nylok:
These are useful if the bolt is going into a blind threaded hole.
Added The Following
As I said in a comment below, ...
- 6,765
24
votes
Turning a hard to access nut?
A Crowfoot Wrench would work nicely. A 10 piece set of these is only $15.00
- 3,675
22
votes
How to prevent bolts from rusting and sticking in the toilet tank?
The best solution is to purchase a new set of bolts that are made of stainless steel or brass. Both will not rust the same way that a iron or steel bolt will. They will cost a little bit more but will ...
- 64.1k
20
votes
Accepted
How can I get a bolt with no head out of my wall?
I would just clamp my drill's chuck on that puppy and spin it out.
- 129k
19
votes
What ikea screwdriver type is this?
It is called a "hex key", "Allen key", or "Allen wrench".
You can also find socket wrench tools with this hexagonal drive shape. Hex key socket wrenches are almost always stronger than Allen keys, ...
- 14.2k
19
votes
How can I cut off the rusted closet bolts holding my toilet?
Bolt cutters are not really the best tool for cutting off rusted closet bolts. I usually use a "mini-hack" saw:
- 35.1k
19
votes
How can I stop bolts from loosening over time?
Lock Nut / Double Nutting
If there's enough thread exposed through the joint, then you can fit two nuts. The first nut is tightened to the required torque for your application, and the second nut is ...
- 10k
19
votes
Why are deck joists supposed to be on top of posts, not bolted to the side?
For a steel bolt in steel beams there is no differential thermal expansion (the beam and bolt expand and shrink the same with temperature changes) and no hygroscopic swelling and shrinking, since ...
- 202k
18
votes
How can I cut off the rusted closet bolts holding my toilet?
I would caution against using any bolt cutters on the toilet hold down bolts. The reason being that they typically will apply a significant pressure against the porcelain base of the stool and crack ...
- 64.1k
18
votes
What is the right tool for old, rusty, flat cross head bolts?
I would use a small grinder ( Dremel) with a cut-off wheel and cut the nuts off.
- 8,271
17
votes
Accepted
Fix drywall that lost strength due to hanging curtain rod
As you have found out, curtain rod supports do not do well hanging from plaster anchors. They really should be attached to studs, but where that is impossible, toggle anchors give you a chance at ...
- 33.6k
17
votes
How do I use threaded inserts?
You need to pre-drill a large but shallow hole of the correct depth, and use the bit size recommended by the manufacturer for the material you are setting those into. Too small and you'll crack the ...
17
votes
How can I stop bolts from loosening over time?
To round out the smorgasbord a bit:
Drill a hole through the nut and bolt when tight, insert a cotter pin.
Or drill a hole only through the bolt and use a castellated nut. Actually two holes at right ...
- 202k
16
votes
Accepted
What kind of bolt is this?
This is a pop rivet, not a bolt. It can only be removed destructively.
Drill out the center with a drill bit meant for metal (as opposed to a brad point bit, for instance) until the flange come off. ...
- 896
16
votes
Turning a hard to access nut?
I'm a gas fitter and service tech. My bag has the tools to do the job. Sometimes these tight spots require a bit of a turn with one tool and a bit of a turn with another. A lot of the available arc ...
- 6,314
16
votes
Accepted
Identify this screw head (was: Security Torx)
This is a tamper proof torx screw. There are torx bits with a hole in the center that will remove them, if you are bold you can try smacking the center pin with a punch at an angle (small ones usually ...
- 102k
16
votes
How do I remove this bolt from my bedframe?
Remove the metal rail.
In the opening, you now have enough room to insert an open-end wrench.
The wrench has a slight angular offset. Push down on the wrench as far as it goes, remove it, flip it ...
- 5,856
15
votes
Turning a hard to access nut?
What you may be overlooking, or what may not be present on your wrench, is the the open wrench is not square to the shaft. It is canted by 1/24 of a circle (15 degrees).
As a result, there's a 30 ...
15
votes
Turning a hard to access nut?
The best tool I have found for the type of application you are working with is a 12-point split-box wrench. These are also available in a 6-point design.
(Picture Source: http://constructionmanuals....
- 64.1k
Only top scored, non community-wiki answers of a minimum length are eligible