How to remove the buckle from any Suunto strap:
After talking to a forum member that showed a pic of his Suunto strap with a different buckle, I had to give it a shot with 3 different Suunto Core straps. The straps I am removing the buckles from are- Light Black Elastomer strap, All Black Elastomer strap, and Orange Elastomer strap/with lugs.
1. The first thing you are gonna need are two very good quality flat heat screw drivers that fit the screws on the end of the buckle. Make sure they have a fine flap sharp tip in the end. I also used a small vise grip pliers to hold one of the screwdrivers strait and solid.
2. Boil up some water and submerge just the buckle end into 1/2" of hot water for 10 minutes. This is to loosen up the ultra hard locktite Suunto uses. While the water is boiling, take the strap off of the watch for easier use and keeps the head of the watch from getting damaged.
3. I placed one screw driver into a set of vise grip pliers to make a home made jig. This will keep the one screwdriver from turning and in a fixed position because you will need all your strength to turn the other screw driver. I used a 1" book to elevate the buckle and left the vice grips hang off the side. It makes a perfect jig to hold the buckle flat against the book and the vise grip pliers keep the attached screw driver level.
4. Now as the fixed screw driver is lined up with one side of the buckle and in the screw, place the other screw driver on the other side and bear down and turn for all you got.
You may need to heat the buckle up a few times as you are working on it. Go slow and try not to strip the screws. Believe it or not, they will come out. I did three buckles in a row. Note: this can be a bugger to do. Go slow.
I found that the chrome silver screws are harder to work on and the screw driver wants to slip out easier.
I replaced the All Black buckle to the light black elastomer strap. The tang is smaller on the black buckle than the one that comes on the light black strap. I made two little fillers on either side of the black tank. I used 2 small black shrink wrap tubes I cut about 2mm per side. I heated them up to fit exactly. I think it looks factory. The silver buckle will fit on the all black strap and will compress to fit. The silver buckle looks like the same strap on the Regular Black Core.
Special thanks to Tigeryear for the idea of heating up the buckle.