Router depth

[Wend]

Hi folks,

I'm trying to understand how deep you can go with a router; I wonder if anyone could help me please?

If I had a T4U3000 then I believe I could make up to a 12mm deep groove in the middle of a piece of wood by simply plunging and then moving sideways (although doing this in multiple passes may be kinder to the machine and bit).

Would I then be able to adjust the bit/router and deepen the groove with a subsequent pass? And if so, what is the deepest that could be achieved?

Thanks,
Wend

 

[custard]

You'll often hear that the depth of cut should be no greater than the width of the cutter. That's not a bad rule of thumb, but it's still just an approximation.

For example with a good quality, solid carbide, spiral upcut bit, working a mild timber you could easily go two or three times deeper than with a cheap, single flute cutter in a tough and abrasive timber.

So, start with the rule of thumb, but then aim off for your own particular circumstances.

 

[Wend]

But that's for a single pass, isn't it? My question is how deep can I actually go in total.

That page describes the bit as having a 12mm blade height, so 12mm is clearly fine. But it also has a 50.8mm total shaft length. Does that mean that I can cut up to 50.8mm deep in total, with multiple passes?

Hmm, actually, is the rest of that 50.8mm going to be 1/4" diameter? So I'd need a 3mm collet to go any deeper than 12mm?

 

[sunnybob]

Any good router bit will have a mark on the shank as the furthest out from the collet it should be.

The further out the bit is, the greater the centrifugal force and the greater chance of wobble and possibly catastrophic failure.

Its possible to go a little further out than that line if you are taking very fine cuts, but once past the line, you are in dangerous territory and on your own.

 

[Phil Pascoe]

You can sometimes adjust the cutter to go deeper, but you must ensure enough of the shank stays in the collet - many cutters have a mark on them you shouldn't go below. If you're trying to do deep cuts - such as a lock mortice - it's safer and less stress on the cutter and machine to remove as much waste as possible by plunging as there isn't then so much sideways stress.

 

[Sideways]

To the OP.
Yes.
You linked a solid 3mm dia cutter with an specified 12mm cutting edge.
So it should be capable of that.
You need to have sympathy for the cutter and the machine. Make multiple passes - maybe 2mm deeper each time - to get there. Don't feed too hard with a skinny bit like that and remember that solid carbide is more brittle than steel, though you don't have to worry about failure of the brazed joints between the cutting edges and body.

I have 6 and 8mm dia quarter inch bits with 25mm cutting edges. They are perfectly capable of cutting 25mm deep, but multiple passes and at a sensible feed rate, with the shank properly inserted in a good collet. It's just a matter of leverage. Long bits put more stress on the cutter shank and the router collet.

Clearly you get it, but I've noticed many amateurs who seem to think that everything can be routed in a single pass. Sometimes you can. Often it's wood butchery with the poor machine howling in pain ! If you snap the cutter, you've learnt something about it's limits ...

Cheers

 

[sunnybob]

Also, a safety warning.
Use goggles when operating a router table. Its the only machine I use goggles on.
When a lump of metal spinning at 30,000 rpm comes loose............ :shock: :shock:
I have had one cutter lose its blades. Trust me, you do not want to try your luck.

 

[Raymond UK]

Also, a safety warning.
Use goggles when operating a router table. Its the only machine I use goggles on.
When a lump of metal spinning at 30,000 rpm comes loose............ :shock: :shock:
I have had one cutter lose its blades. Trust me, you do not want to try your luck.

Or bearings that collapse and start spitting metal balls at silly speeds....