How does one go about separating a track? Need to rebuild the final drive on my D9D 18A. Built a track pin press that I thought would get the job done but I got up to 70 tons of force on my 100 ton ram and my press frame started bending (a pair of 1"x3" plates, bending the strong way). Moved the pin about 1/4" on the inside (enough to push the link together) but that's all I can do.

How many ton should it take to press the master pin out? Does it take more than 70 tons or could my pins just be worn enough that they are catching on the worn edges and I need to get the pin centered in everything before it will come out?

1.- Are you certain you are attempting to remove the master pin?
2.- Did this pin have plugs in each end and if so were they removed?
3. - Since you have attempted to push pin with a home made press and failed - leaves you a couple of options
Have you tried cutting an X in each end with the hot wrench ( acetylene torch) Slag will be flying and be careful not to cut the link
There are some "new" tools out there since I worked on tracks - better cutting tools - some here will be more helpful - Plasma?
If you are trying to drive pin out with a big sledge and drift - make sure the pin is aligned on the sprocket and with your partner - the biggest hammer you can swing- 16-20 pounders.
Hold the drift with a pair of tongs or big pliers, be careful of flying metal - wear PPE! Sometimes the combination of heat and the shock of a big hammer will help to move the pin.

Is severe case, links have been cut but that then requires full track disassembly and new link installed, same process as turning pins and bushings.

CTS

I would add a little heat when your pressing get up to your 65-70 ton then hit with heat that way you can see it start to move by the presser gauge. yes there lots of forces required. I think the big track presses are 250 ton for doing pin turning but that would be on the bigger 10 and 11.

Be aware if original 18A type master pin it needs to be pressed/pushed from the inside-out once the plug is removed.