Routing a rebate (what's the best way?)

[DavidE]

Hi there,

I've got some rebates to cut for some door frames. I've cut similar ones in the past and had some excellent results and other times there has been a bit of feathering (also called spelching maybe? along one of the edges. I have never managed to come up with the definitive way of avoiding this. I imagine this will be heavily dependant on the direction of grain of the wood too and on a board where this is changing it can be tricky.

So here's my question - which of the methods described below and in reference to the drawing is most reliable?

(I guess it's worth noting I do have a large diameter cutter that will cover the required size for the last pass.)

Method 1:
Take a scoring cut like A and keep going progressively deeper in a number of passes till the dotted line is reached.

Method 2
Take a scoring cut like B and keep going progressively widen a number of passes till the dotted line is reached.

Method 3
Take a scoring cut like B, then take the A scoring cut and continue with the A cuts till the dotted line.

Method 4
Same as 3 but after scoring following the B cuts.

Thanks, David

 

[OPJ]

I think your third method is probably the one to go for. No harm in scoring a line before you cut (as long as that line won't be left in afterwards).

Are you using a hand-held router or one that's table-mounted? Either way, it's better to gradually increased the depth of plunge and I think you're better working from A with both setups because it'll provide more support for the router or table as the material is removed.

 

[DaveL]

David,

The way I would do this is to cut 75% of the rebate on the table saw, just two cuts to remove the bulk of the waste. Then finish using the router, much less saw dust, less strain on the router and I have a spare strip of wood that may be useful for making a bead to hold glass in the door.

 

[DavidE]

Hi Olly,

Thanks for your reply - I should have said that it was table mounted. So I can always have the board flat, as the B cuts just involve widening the fence rather than the depth.

Method 3 is the one I've used the most successfully in the past (not always perfect though). Thanks for your reinforcement of that. I'll be interested if that is the consensus or if there are alternative views.

Cheers
David

 

[DavidE]

David,

The way I would do this is to cut 75% of the rebate on the table saw, just two cuts to remove the bulk of the waste. Then finish using the router, much less saw dust, less strain on the router and I have a spare strip of wood that may be useful for making a bead to hold glass in the door.

Hi Dave,

You got in there between me previewing my reply to Olly and clicking submit!

I know where your coming from with that suggestion, however, I can't try that due to the inevitable guard removal (which on my saw would mean there would be no riving knife present. The amount I need to remove is 35mm x 13mm so not too onerous (I hope )

Thanks, David

 

[jasonB]

Option 4, climb cut B then go in at full depth, the climb cut will be cutting with the grain so you won't get tearout. Just make sure you have good hold downd and a feather board to stop the risk of kickback.

Jason

Option 5 buy a spindle moulder :wink:

 

[Sgian Dubh]

Option 4, climb cut B then go in at full depth, the climb cut will be cutting with the grain so you won't get tearout. Just make sure you have good hold downd and a feather board to stop the risk of kickback.

Jason

Option 5 buy a spindle moulder :wink:

Hmm? Climb cutting with an inverted table mounted router is definitely somewhat risky in my experience, even with hold downs and the like. It's a cut I strongly recommend inexperienced users avoid when I teach routing techniques. So, it's my assumption that anyone asking this question is by definition inexperienced; an experienced operative wouldn't ask and they'd already know appropriate techniques for routing a basic rebate of this type.

A fifth method not yet mentioned that works well is to set a marking gauge and score a heavy line at the limit of the depth of cut. For a fairly small run this is reasonably efficient. For a long run of many linear metres I'd assume most people would be using a spindle moulder anyway and the problem of spelch essentially disappears. Slainte.

 

[Tusses]

is 'speltch' a real word ?? its an ace one if it is

 

[Smudger]

Yes it is (and it means what you think), but don't look it up in an online dictionary if you are easily offended by descriptions of messy sexual practices...

 

[OPJ]

My tutor's the best for this as he actually pronounces it "splelching", as in splelching through the mud! I don't have the heart to tell him otherwise - even when he's talking about Karl Hotley's planes!! :wink:

 

[DavidE]

Thanks for all the replies

I knew someone would suggest a Spindle Moulder (no comment :wink: )

I had a fiddle round with some offcuts of the Oak I was using. I didn't have any means of clamping feather boards down securely enough to try Jason's suggestion. However, with a bit of trial and error I actually found that the B cuts all the way were best (for that timber and the cutter I was using.)

My reason for asking was to try to collect best practice and I will certainly remember these and try again to find the best way.

Cheers
David

 

[Anonymous]

I'd remove most of it on the table saw using a normal blade (I don't use a dado set) and if neccesary clean it up with a router or preferably a large shoulder plane (or rabbett plane)