Well the first frame is away at the painters, so today I've been attacking the forks of the second frame.
The second frame has been well used and therefore had a fair amount of corrosion on it, least of which was one seized bottom bracket plate, and the worst was the stem........the wonderful world of galvanic corrosion!
BF&I (Brute Force and Ignorance) managed to get the BB plate off, but the stem refused to budge. At this point every trick that I could remember came out to play?
1. Smacking it with a wooden hammer
2. Smacking it with a metal hammer
3. Smacking it into the steerer tube to try and break the seal
4. Leaving it over night with thread release soaking inside (an ammonia based solution that actually breaks down the Aluminium Oxide that's caused by the galvanic corrosion).
5. Hitting it from the crown end with a blunted chisel
6. Pouring boiling water inside and the allowing to cool (to again try to break the seal)
7. Heating it with a blow torch
I then decided to give up and simply hacksaw the stem off just so I could get the forks out of the frame, and remove the headset.
This left me with the forks free of the frame (as in the first pics) but with a section of aluminium stem still stuck in the steerer tube, where it has stayed put until today's efforts
So a couple of piccies of today's process
This first pic shows the two 3mm grooves I cut into the top remaining portion of the stem. These grooves were cut all the way through the aluminium until the bur I was using touched the steel steerer tube of the forks. The idea here was to a. give me a good key to get some turning purchase on the stem remains, and b. remove some material from the stem so that I could compress it a bit to make it smaller, and hopefully allow it to release from the inside of the steerer.
I then got hold of our gas and air torch in our lab, and fired up the air to get a serious blue flame before cooking the top of the steerer tube lightly to heat it up again to try to help break the aluminium oxide seal between the steerer tube and the stem insert. After cooling the stem I then clamped a metal bar into the vice and inserted the keyed grooves in the top of the stem into this bar and tried to twist. It didn't give, so I turned the forks upside down and inserted the remaining stem (about 5mm) into the vice. I then turned the vice until it compressed the two grooves closed and then gave the forks a twist........
One pair of forks ready to be inserted into the frame again. I've cleaned the threads up a bit since that pic, and will try to polish up the inside of the forks to tidy up the mess from the corrosion before I stick a new stem or adapter in there.