Advice please - Should I do this??

[old_picker]

Need to take a whisker [1/16"] out off the bottom of a 2" x 1 1/2" x 11/16" deep trench with a 1/2" mortise bit. The bit has 1/4" shaft with 4 bearings on it which will help support the shaft. [I thought] The cutting head depth is shallow 1/2". It's quite a small bit

I have 13mm of the shaft into the collett. Is it enough??

This a very small job but dont want wreck the job or me.

Thenks for your advice.

[Wood Borer]

I am not a router expert but is it possible to use a mortise chisel or a hand router plane?

[Knurl]

I think 13mm is too little but depends on the nature of the flanges inside the collett. I'd recommend a minimum of 20mm for safety sake if you don't want to wreck the work and perhaps your body.

[old_picker]

depends on the nature of the flanges inside the collett

Please explain the above not quite sure what you mean by flanges inside the collett.

[ian]

Need to take a whisker [1/16"] out off the bottom of a 2" x 1 1/2" x 11/16" deep trench with a 1/2" mortise bit.
This a very small job but dont want wreck the job or me.do you really have to deepen the trench? It may be much asier to take 1/16 off what goes into the trench

how did you cut the trench in the first instance?

ian

[BobL]

What sort of wood?

If there is 13 mm in the collet and the trench is 11/16" deep that means the total length of the bit is 17.5 + 13 = 30.5 mm. That is a short bit - I can't see how you can have 13 mm in the collett, 1/2" or 12.7mm cutting length and 4 bearings in the remaining 4.8 mm???

It doesn't add up!

[Harry72]

13mm is not enough!

[Driver]

If your instinct is telling you this is dangerous and your intellect tells you to ask the rest of us because you think it's possibly dangerous ... Do I need to fill in the blanks for you?

[Rocker]

Why not just use a longer bit? Something like a 1/2" solid carbide spiral upcut bit, for instance. I agree that 13 mm in the collet is not enough.

Rocker

[Bob38S]

I was always under the impression that the bit should be as deep as possible in the collet without touching the bottom. Extending bit out of the collet puts excessive strain on the cutter and the machine. I would go with Ian and shorten what goes into the trench - if this is not possible then go with the longer bit.
Lastly - if you do not feel totally confident with what you are doing - then don't do it. When confident accidents can still happen but you are usually aware of what could happen - if not confident then the accident is far more likely - with a router that can get very ugly very quickly.
Just my thoughts for the mix.
Bob

[ian]

Ray
I've had another thought about your trench
Need to take a whisker [1/16"] out off the bottom of a 2" x 1 1/2" x 11/16" deep trenchif as you've described it the trench is a rectangle, i.e. the ends aren't rounded, then if you use a router you are going to have to finish the corners by hand. And if the bottom of the trench is a "show surface" then you probably will have to use a hand router for the corners so why not do the whole task with the hand router?

If the bottom is not a "show surface" why not deepen it using a chisel ?


ian

[old_picker]

http://www.carltonguitars.com.au/resources/Image/BC2/BC_2_Pocket_cut1.jpg

Why didn't I post a pic to start with dohhh!!!

Anyway I needed a whisker [1/16"] off the bottom of that pocket. It had to be dead flat and exactly parallel to the top face. My handskills with a chisel are quite primitive so router was the only option.

Having regard for the forgoing warnings and my remedial arithmetic skills I decided to attempt the cut. The router I use has a variable speed and can run quite slowly with power enough for a good clean cut on a small shaving like this one. So with a full face mask and heavy jacket and safety gloves on i turned on the router at about 20% and slowly worked through the job. The 1/2" CMT mortise bit shaved it off with nary a stray fibre of wood.

Myrtle is the species by the way.

Thanks for the advice.