Jason has it. Stroke / blade length / work capacity relationship is typical for power hacksaws.
That's a nice looking machine with a lot of capacity for its size.
I find blade wear isn't an issue with my Rapidor but putting the blade in the right way round is important. Cuts towards the fixed vice jaw! Probably be worth scheming out some sort of lifter device to take the pressure off on the return stroke. This would almost certainly greatly increase blade life and, probably, improve the cut. Bound to be something on the internet to copy or take inspiration from.
Do make a solid setting device to adjust the fixed jaw dead square to the actual cut. Hard to get closer than a couple of degrees with the existing type of scale. My fixed jaw Rapidor is square to a thou or three per inch with a sharp blade. No reason why yours shouldn't be of similar performance. Obvious way is a tight fitting block in the slot the moving jaw slides in with a carefully adjusted blade to set the fixed jaw against. I'd probably make the blade double sided with the other side at 45°, or another useful to you angle you. So nice not to have to mess around correcting things for weld-it-up jobs.
Clive