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Ive done many things in life, but I’m still pretty new to the router world;)

I’m not sure why I’m confused on this, but for some reason I think I am (see I’m confused about being confused too)

I’ve been using my router table to cut truss rod slots. But the router wants to pull the wood through the bit and off the table. This is clearly because I’m feeding it in the wrong direction (climb cut) right?

BUT everything I see says go from right to left if your looking down on the table. This is the direction I’m going!

Why is it still pulling?

Here is a piece of art hand drawn by me for your enjoyment that illustrates what I mean.



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Just a thought…. Maybe it’s the bit? There’s a down cut but in the router …


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Too big of a bite probably. Do it in multiple passes.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

My advice:

Cut only 1/8” of depth at a time. Use a featherboard to keep the neck snug against the fence. Use sharp, clean router bits.

If the bit is running counterclockwise it should be pulling the work into the fence. I use an up-cut spiral (pulls waist out of the slot) bit and am able to get vey clean results in one pass. The one problem with making multiple passes is the bit center can shift slightly making for a sloppy fit. How big is the router you are using? A small laminate trimmer may not be stiff enough for the job.

Best M

In a buried cut, there should not be any issue with lift or lateral forces (they are pretty balanced at reasonable feed speeds) unless the bit is dull or perhaps with a larger downcut bit (which will lift the work in a table). Once the main channel is milled, all the caveats concerning 'trapping' work between the fence apply...no backfeeding allowed.

What bit are you using, do you have dust collection pulling the chips/dust out of the channel, and what type of trussrod are you using?

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For the times they are a changin'

- Bob Dylan

Hey thanks for all the hints

Bit: 1/4” whiteside spiral downcut

Dust collection is hooked to my big jet collector

Router: Bosch 2.25 Hp


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Not really a good application for a downcut bit. A normal uncut will pull the work into the table, helping control.

Just a thought. I’m not sure what the current setting is (not there now) but should the router be on high speed. I’m assuming it should. Maybe it’s been accidentally turned down?


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Ditto. Plus, getting the chips and dust out of the channel is important, and a downcut bit is going to make that harder, not easier. Use an upcut bit or a straight bit for this application.

If you really want to use the downcut bit, I will repeat the advice about only taking 1/8" of depth at a time. Michael is right that the side walls can wind up a bit messy (depending on some factors), but getting the chips and dust out of the channel would be an overriding concern for me. With a downcut bit, stuff has trouble finding its way out of the channel.

For a round-bottomed trussrod like the Martin 2-way, a 1/4" solid carbide core box bit gave us flawless milling and the round-bottomed slot reduced stress concentrations at the lower corners and end of the slot. We had no issue with full-depth passes, and could mill a wider slot by a combination of partial passes and plunge cuts aligned with the fence.

_________________
For the times they are a changin'

- Bob Dylan