Some more progress, and a solution to a problem. Today I set about sawing the ribs – the sides of the mandolin. The ribs serve little real purpose other than to separate the top plate from the back and define the air cavity between the two. I settled on 50mm wide, 2mm thick and about 600mm long as a starting point. That would leave sufficient timber to scrape it down to remove machining marks and thin enough for steam bending to shape.

I ripped the boards to 50mm – no problem there on the Triton Mk3 saw bench, but the first attempt at resawing to cut thin strips failed with a very nasty and abrupt stop as the thin slat tore off and half disappeared between the saw bench and the blade, trapping the saw blade and bringing the whole process to a rapid stop.

The blade guard prevented kick back, so it was just a technical problem. I unplugged then freed up the saw, and reset it up straigth again as the force of the sudden stop had moved it out of alignment.

I pondered this for a bit and remembered the solution – make a zero clearance sacrificial false table. I had some 3mm MDF (medium density fibreboard) and found a piece about the right size – enough to cover about half the triton saw table. I set the blade to the height I wanted for the cut, then I removed the guard – note if you do that you need to be absolutely focused on your safety. I positioned the MDF above the blade, started the saw, and with one edge braced against the riving knife I lowered the MDF onto the blade, making sure that my hands were well clear of where the blade would cut. I then stopped the saw and there was the false tabletop with zero gap between the saw blade and the MDF. I cut a slot for the fence bolts, then clamped the MDF in position and set the desired gap between the fence and the saw blade.

At that point I replaced the blade guard and made a trial cut in a pine offcut before going back to the precious Tasmanian blackwood, ready to make the thin strips that will eventually become the sides, or ribs of the mandolin.

zero clearance saw table

You can read more on the progress so far as follows:
Part 1 – making a start (selecting the timber)
Part 2 – preparing the top
Part 3 – cutting out the back
Part 4- starting the ribs
part 5 – sawing the ribs

Cheers
Jerry

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