Y why not? as long as you can get a 35mm plunge. 8 narrow slots - 2 in each face of a long piece of timber, isolates the corner blocks and leaves a centre core. Cut off the end so you now have 5 sections connected at one end - the 4 corner sections and the core. Take out the core with hand tools. PoP. And if you need more than one piece like this, cut them in pairs so when you cut through the middle of the routed slots you end up with two pieces.
Where's the theory. I'm making some French doors literally as we speak. I know my way around a router!!
No one is suggesting doing it all in one pass. Everyone who has mentioned a hand-held router so far in this thread has mentioned doing it in multiple passes. As many passes as necessary, depending on several factors ... the hardness of the wood, the sharpness of the bit, the power of the router, etc. The 'theory' might be to do it all in one pass, but the practice is doing it in as many passes as necessary ... but it can certainly be done with a 1/4 router. I only have a 1/4 router and I've done plenty with it that's more demanding than what the OP is trying to do. Admittedly mine is almost as good as they get (Elu), but even a relatively low-end one should cope with may be a few more passes.
Yeah it's a good idea, I'm going with the router option. Should I opt for a thin or wide bit? I'm thinking a thin bit. I won't remove all the material with the router, just cut the outline of the joint which will come away after drilling a hole at the bottom of the cut. I also have extra length that I can cut off after routing. Did you mean that I should use the extra length to gauge and hone the cut before going into the actual joint? I've got a makita parallel guide with a 'micro-adjuster', so I don't think it'll be too hard to get mm accurate.
The sharpest bit. Say 6mm? The extra length gives you a better surface to run your fence along. If the timber is short the fence falls off the end and you can get a wobble.
Note to original poster on this wear safety glasses. Even with a 1/2 inch router i reckon you'd need 5 or 6 passes( per slot)If you don't break a cutter I'll be happy.
As Cecil says take plenty of passes. If you use a 6mm cutter take 6mm cuts. You only break cutters if you get greedy with the cut. Also if you have a micro fence you could do the bulk of the cutting inside your line a smidgen then just take a single fine cut - half a mil say -at full depth
y as a rule of thumb don't take more than the width of the cutter at a time. n - thickness down't really matter.
If you take a 6mm cut with a 6mm cutter projecting 30mm from the bottom of your router take great care. I would reckon a 2 mm cut at full extension maybe 1 mm! But i would wear safety glasses. It's all rubbish anyway cos i bet a 1/4 inch cutter with that depth is not made. Think about it 1/2 inch kitchen Worktop cutters only have to cut 40mm and there slightly dodgy.
you might be right length wise on a 6mm cutter - it's on the limit for a typical 55-60mm long cutter, but there's plenty of 7-8mm cutters available with 70mm overall length and 1/4" shaft which is plenty to get a 35mm plunge. I agree, take fine cuts with a long cutter, but there's no different force on the cutter whether it's sticking 10mm below the plate or 35mm.
It would have been much quicker to cut by hand than read all of this thread!. It's four cuts down the post and break/chisel out the waste or cut it out with a coping saw. Quicker, quieter, less messy/dusty waste and probably safer. Oh, and a fifth cut to reduce the one spur (which you'd still have to do even if you used a router).
Y, I'd hand cut it if I couldn't put it on the table. Few minutes of a job, but unless you have a sharp saw and can cut straight - and its a 170mm rip cut, cutting slots with a 1/4" router has more chance of staying neat, even if you finish off by hand. To hand cut you also need a solid bench to keep that post nice and upright. easy if you have the right kit, but a wobbly workmate wouldn't be any good!!
I didn't read the other posts so forgive me if this has been answered or I am out of context, but I would use a band saw and a chisel. Failing that a table saw and a chisel. Failing that, make an MDF jig and use a router. Worthwhile making the jig since you have a number of cuts to make. If you have a 1/2" router it's easy because you can get very long 1/2" x 1/2" bits. Failing that, a hand saw. Failing that, the wife's teeth.
I disagree with your rule of thumb as that implies it’s ok to remove up to 25mm if using a 25mm wide cutter. Even in the workshop on the overhead router I’d never take more than 6-10mm in a single pass
Ditto removing large amounts of material on anything but industrial machinery is a no no. Even a 13mm by 36mm rebate for an interior door is a tidy amount of wood to remove.