Nice find Mecha!! That seems inherently more dangerous to me but then again I’ve never used it.
The woodcutting performance I found to be disappointing was with blades specifically meant for cutting wood, I wasn’t trying to do that with the masonry blade. I just don’t think it’s a very efficient design for clearing chips. The blades resembled that of a standard bow saw. I did not test in nail-embedded wood but I am 100% sure that would have damaged the blades seriously. As far as I know there are three choices of blades for these saws:
- a scalloped knife-bladed edge, like a giant bread knife or electric carving knife from the kitchen, meant for cutting insulation
- the woodcutting blades I mentioned whose teeth resemble a bow saw, clearly meant for cutting clean wood, like pruning or firewood sort of application, or perhaps rough construction like timber.
- carbide tipped blades for clay brick, aerocrete, poroton, etc.
I’ve never seen Alligator blades resembling a “demolition” blade for a recip saw. I think the reason why these are so good at cutting the aerated masonry and clay block is because those materials have tons of air space for the “sawdust” to escape into and fall away from the cut, but without a long or continuous stroke it clears chips poorly from wood.
I’m not exactly sure how the gearbox works. It’s easy enough to find a parts diagram for these saws (i.e. DCS397) online, but all the magic is hidden. The gearbox is shown as a sealed unit. You can see the two rods which engage the blades below the gearbox, and the slots in them make me think there’s some kind of eccentric underneath the gearbox, but it’s impossible to say from just those pictures how that actually works. It could be as simple as one shaft coming out the bottom of the gearbox with two out-of-phase cam lobes on it with one lobe driving each rod.