Old paint

[socko47]

I always try to gently tighten the cap to break the seal. After cleaning the cap and threads apply some vasoline to the threads to prevent future stuck caps. Also, since we use small amounts, scooping out the paint keeps the paint from getting squished over the threads by he cap design. Caps have an internal projection that pushes the paint when closing. If you are a tube squeezer to dispense and are careful not to get paint on the threads the following trick helps. Holding the tube by the main body with one hand and GENTLY and slowly pull down on the tube by holding across the pointed end of the tube with a finger and thumb of the other hand. This tends to suck the paint back into the tube before putting the cap back on. This works for most but the thickest paint.

[snagy]

According to my practice:
I boil water in the teapot, wait till it really boils.
Then I liquate the water in fine flow to the cap.
That always helps.
Sandor

[PJDeluhery]

I use a hair dryer (electric) plus a pliers to break the seal when needed. Then clean the threads as mentioned previously.

[willie]

Brian that's great my last resort would have been a bit of C4 but that might have just been to much over kill Willie

[Brian]

Many thanks for the advice guys,  not a blow torch but did try the gas cooker!!!
hot water got the beasties off in the end 
 

[Nicholas Ball]

Brian doesn’t do candles Ed, he goes in for bigger things like blow torches

That will get the lid off, and half the tube! 

[johnr]

I usually find that running boiled water over the cap does the trick. You have to use them more often Brian to make sure they don't get stuck!!!
John

[willie]

Well I have used plyers , soaked the top in Lacquer Thinner , Also go the kitchen; and use a Tupper wear sheet for opening tops of Jars. Once open  use Dental tools and cleaned out the groves on the tube and top . Then go to you local Hardware  Sore and get a small wire brush  This you use on the tube groves An other way is I use a spray can of Safe Paint Remover and a toothbrush and a throw away aluminum baking pan from the Dollar Store.  Once you have cleaned the top  wipe it down with Lacquer Thinner making sure there is no remover left on the top. Willie

[Ed Humphreys]

The heat of a candle flame, carefully applied, usually works for me. I also have a small vice (some say I have many) on the edge of my painting bench, which has enough grip to finish the job.

[BobLeighton]

Run or soak the cap in hot water or try a rubber band wrapped around the cap

[Erich]

I sometimes try a nutcracker to rotate the cap ..


no joke, I have one at my workplace

[Brian]

Here's one for you!!   tubes of oil paint with the cap locked on with paint, how do you get the cap off without damaging the tube??
Yep!! I have a few hahaha