Interesting drawer joint idea

[Eric The Viking]

I thought arbours that could take dados were illegal in the EU

My understanding was that you're not allowed them in a commercial setting due to the need for the motor to be braked (so it spins down quickly when switched off) - the mass of the dado head is too much.

You can (IRC) buy dado head capable machines for private use.

Steve Maskery covers this in his Compleat Tablesaw DVD.

He talked to the HSE quite a bit during the making of it. If he's not laying patio today I'm sure he'll comment properly.

E. (largely ignorant in these matters!)

 

[siggy_7]

Re dado blades, I think the legal requirements are for the blade to stop within 10 seconds and for the blade to be guarded. So if you have a saw with a big enough brake, and have/make suitable guarding arrangements, then you're HSE compliant. Most saws don't have brakes strong enough to stop a dado blade quickly enough as they weigh in typically 3+ times what a normal blade weighs.

I haven't seen fold-up joints like that before, looks interesting. I think using 9 or 12mm sheet goods it would be a quick way of making drawers that only needed to stand up to moderate abuse.

 

[Steve Maskery]

Siiggy is correct. Dado stacks per se are not illegal, it's the guarding and braking issues that makes using them illegal in a commercial workplace.
My Xcalibur has a long arbor and even a full stack comes to a stop in6 seconds or so. The motor is so big that the increased mass of the dado is a relatively small percentage of the total spinning mass. That would not necessarily be the case on a smaller, lighter saw.

So then we come to the guarding. We can't use a standard crown guard mounted on the RK, but an overhead SUVA guard would do, or a guard fixed to the fence, if the dado was being used to groove for drawer-bottoms, for example, because the blade is close to the fence. On one of my DVDs (I forget which, TBH) I show how to build a fence for this operation. It's both guarded and has featherboards built in. I think it's as good as I'm going to get on the rare occasion that I use my stack.

Incidentally, you could use a standard dado to do the same thing by tilting it to 45 deg. OK you wouldn't get the interlocking bit, but it would be strong enough for lightweight use, I'm sure, especially if you splined it afterwards.

 

[sploo]

Interesting, thanks. Don't think my Axi TS200 would do it though

TBH I can see the benefit if you're doing deep 3/4" wide dados on huge lengths of material (due to the speed on a good saw), but a router table is fine for most small volume use I suspect.