Got these pics from our reader Stanley. I've invited him to join the forums and let us know more about the project, but from what I know now I'll post!
Your site is one of my favourites and I have picked up quite a few good ideas from your projects. Although many recommend using material readily available in the USA, one needs only to adapt the design to locally available materials.
When I made the hacksaw machine, I was working with 4 inch hollow section M/S and 4 inch round tube and hence the large crude vice fitted to the machine. I did not have a shaping machine so utilised phosphor bronze bushes running on 5/8 inch round bar. They work well but need some oiling when working. The other rotating parts also use 5/8 inch bushes. The motor is 1/4 hp 230 volt and the gearing used was from my scrap box. When the cut is finished the arm drops down to cut off the power. There is provision to make angled cuts by adjusting the angle of the rear jaw of the vice. Some care is needed when fitting the vice to the machine and also some packing to achieve a 90 degree cut in both directions. I can only remember having fit a new blade once during the machine's lifetime . There are no castings employed, all is constructed from standard steel sections. For the bow I used T section but other sections would work just as well. Using this machine keeps you busy as the cut is finished almost as fast as you can select and mark up the next piece. Needless to say it takes the heavy work of hack sawing large sections, out of the job and is much more accurate. Two low roller stands are needed to support long sections and catch the cut off piece.
If your members are interested I can measure up the machine and prepare some 3D drawings for you.