Removing pin from hinge

[Preistrager]

I've had luck popping one of the door pins out, but the other will not budge. First, liberally soaked hinge with Twister lubricant and tapped pin. Soaked overnight and for two days. Tried air hammer, hammer and drift punch, ground off the head and drilled through the whole hinge, but still some outer portion of pin left in hinge.

Have tried to knock out this remainder, but it doesn't move. Am using various sizes of cobalt drill bits. The pin was frozen in the center section of the hinge (moved in top and bottom). Cannot remove rest of pin! Would heat in the center section of hinge do the trick? With small heat torch? Will be painting whole bus Tuesday, and have to get mirror arm in. Help!

[Scotts 63 23]

I've had a good deal of luck with a propane torch on frozen bolts. Since you're repainting, heat it up!

[Preistrager]

Thanks, Scott, for your enthusiasm! Anyone else have any different (successful) ideas?

[hazetguy]

since you have already drilled, try using the next size up bit until you get through at one point, then it should tap out. the problem is that the pin has probably worn some edges on itself where the pieces of the hinge come together, making it difficult to press directly out. if you get the top or bottom section of the pin removed (by the next largest drill bit method) you should be able to tap it out the other direction. i wouldn't drill all the way through the pin though, you need something for the punch to hit.

[Preistrager]

I did it! I got the pin out!! Since I had already drilled through the whole pin, I had nothing to punch out.

I used an oxyacetylene torch, turned on as low as possible, and heated the hinge til it was a dull red. I was careful not to direct the flame toward the door. Then I drilled with a series of cobalt bits, starting with a size larger than the first one I used. I drilled until the bit went entirely through the hinge. Of course, The heating was repeated numerous times. Then I moved up a bit size and repeated the process. Four bit sizes were used. I finally used the exact size bit to match the measurement of the pin, 19/64th. It took about 2 hours. The tip of the bits had to be sharpened a few times on a grinder, but they worked. Hope this may help someone else in the future.

If you use this technique, after you grind the pin head off, remember to use a center punch exactly in the center of the pin, and direct your drill exactly in the direction of the pin/hinge hole. Thank you all for your help!

[Preistrager]

Another pointer that I learned the hard way: if you are hammer punching the pin down (or up), have a friend hold a heavy weight at the opposite end of the hinge to absorb the energy of the hit. This will help prevent your door hinge rivets from breaking away from the door, causing more problems.

[kenshapiro2002]

[Fredrok]

FWIW, a mix of 50/50 acetone and atf has proven to be a most effective penetrating fluid through many tests and personal use through the years. We would suggest it in many customer conversations back in my machining years and everyone was grateful for the "trick" post usage.