Advice for routing a slot

[Jim Crockett]

I am attempting to rout a 1/4" slot (not dado or groove, but all the way through the material) for a jig. The slot starts about 2" into the board and ends about 2" from the other side (material is 6" wide, 1/2" thick).

Any advice on how to accomplish this would be appreciated.

I have tried drilling a starter hole but must not have had the fence set correctly because the bit immediately moved about 1/8" out of the slot. I have about burned up my 1/4" straight bit and find that as I'm routing, the material lurches (for lack of a better description) while I'm carefully trying to feed it - from right to left.

So I decided I had better ask questions and rely on the advice of those of you with more experience than I.

Thanks.

JimC

[Dino Makropoulos]

Jim,
Secure the wood and guide your router between two straight edges.

[Bill Huber]

What I did was to make a template from Masonite. Use the plunge router and a 3/4 bit, this way I could use a 3/4 in. guide. I was cutting 5/16 slots.

I just clamped a straight board to a some Masonite I had and use that as a guide. I made my slot about 10 inches long so I could use it to make what ever length of slot I needed.

To use it I use double back tape and tape it to the board I want the slot in and then clamp stops for the length I want.

One thing I did do was to put a 1/8 bit in the router with the 3/4 in guide and made to little slots at each end of the main slot. This way you can use those little slots to center it on a center line you make on the board.

68819

[Andrew Williams]

I do those with a downcut spiral bit.

[Tim Sproul]

......and find that as I'm routing, the material lurches (for lack of a better description) while I'm carefully trying to feed it - from right to left. .......


This is pretty common, IME, for routing a slot if you're not using holddowns and featherboards or other devices. Any movement sideways can cause the bit to try to climb...leading to that lurching business. Employ featherboards and holddowns to keep the work from moving sideways. As well....are you routing this slot in a single pass? You might consider doing this operation in 2 or 3 passes.

Another alternative is to construct this part of the jig from 4 pieces....2 small 2 inch x 1/2 inch x 1/4 pieces that define the stops of the slot and then 2 larger pieces that define the edges of the slot. Depends on the jig and you.

[joe greiner]

I've used both Dino's and Bill's techniques. Either way, I get best results with a plunge router and shallow cuts; as little as 1/16" for the first pass, and not much more for subsequent cuts.

Joe

[Alex Berkovsky]

How accurate does it have to be? I once had to cut a slot in the jig and just drilled 2 holes with a Forstner bit and the used a jigsaw to cut the slot.

[Jim Becker]

You need to guide the router and only take about 1/4" or less in depth per pass to accomplish this task. Dino outlined a good solution above that is simple and will work with both a plunge router (preferred) or a fixed base router if the guides are high enough to keep the base centered on the line as you tilt it into the cut line, particularly for the first pass.

[pat warner]

A pair of edge guides (http://patwarner.com/double_edge_guide.html)lock the router on the work.

[Lee Schierer]

Lots of good advice so far. You can do this cut on a router table too, but you will need feather boards to hold the work against the fence . Shallow cuts (1/4 '' maximum depth of cut) are amust. Spiral upcut bits will cut better and clear chips better .

[Nissim Avrahami]

Hi Jim

I made many slots for jig parts and all of them on the router table

I believe that you are talking about slots like those
68842

I set the from/to stops and the fence distence and the bit height to 1/8"
68843

I did not drill any hole, just hold the board diagonally against the "from" stop and switch ON the router
68844

Keeping the board against the "from" stop and the fence, lower the board slowly into the bit and start pushing...
68845

Till I hit the "to" stop
68846


I stop the router, lift the bit another 1/8"~1/4" (depends on the router power) and repeat the procedure

niki

[Nissim Avrahami]

Limited to 5 pics...

Here is a 1/4" slot that I made in 1-1/4" thich Oak (12" long)
68847

niki

[Jim Crockett]

Thanks everyone for all of the very good suggestions. From your suggestions, it appears that there are a number of ways to cut these slots. And, also from your suggestions, I think I have determined what I am doing wrong - I have been trying to cut the slot in one pass. This weekend, I'll set it up again and try multiple shallow passes - this seems to be the common denominator in all of the threads.

Thanks so much.

JimC

[Bill Huber]

Thanks everyone for all of the very good suggestions. From your suggestions, it appears that there are a number of ways to cut these slots. And, also from your suggestions, I think I have determined what I am doing wrong - I have been trying to cut the slot in one pass. This weekend, I'll set it up again and try multiple shallow passes - this seems to be the common denominator in all of the threads.

Thanks so much.

JimC

One thing that I have found from being on this forum there are many different ways to do just about everything.
The BEST ONE is the one that WORKS FOR YOU.

And you are correct, don't do it in one pass, even with 3/16 Masonite I used 2 passes.
When I cut my template I just used a scrap board and put my Masonite on it and place both against the fence on my table saw then clamped them down. Used the fence as a guide for the router.