I am in the process of assembling an old 35# Modern power hammer. It seems to be all there, and it looks like it is fairly straight forward. There is one thing that I am puzzled about.
This power hammer has two large pillow blocks that sit on top of the head. These blocks have 2 by about 8 inch cut outs that allow a 2 inch block to slide inside the cut out. there is one on either side, and the pivot shaft runs through these 2 inch blocks. With the pivot arm in place this allows the fulcrum to be adjustable. So far this all makes sense, and after cleaning everything up it all fits together nicely. This is my concern, near the rear of both pillow blocks is a groove or slot. The pivot arm has a pin that goes through and indexes into these slots in the pillow blocks.The slots are arched and the pin follows the slot with the arm in motion. But with the pin in place the pivot is not able to be changed.
The explanation may be as simple as it is just there to make a non adjustable hammer, but in case there is a different reason I thought I would seek advice.