# Dado Jig



## Aragocom (Jan 29, 2012)

Hi
Just completed my router dado jig. Made it out of what I had to spare - 12mm ply, pine and Tasmanian oak. 

I made the far end flush so it can sit on a wider surface - maximum length of the dado is about 810 mm and maximum width 54 mm using a 8mm router bit. Knobs are on top and the two stops at each end stop the router going through the end supports.

Peter


----------



## jw2170 (Jan 24, 2008)

Welcome to the router forum.

Thank you for joining us, Peter.

you will find that jig very useful.


----------



## Aragocom (Jan 29, 2012)

Thanks James. Just used it for the first time and very happy with the ease of setting up and cutting a groove (making a tablesaw sled).


----------



## olwudwurker (Mar 16, 2011)

Great looking jig. I've seen plans for something like this but they show the knobs under the end pieces. Yours look like a better take on the subject. Roy


----------



## Aragocom (Jan 29, 2012)

Thanks Roy

The jig was built to cut several stopped grooves across / along a large homemade tablesaw top for T-tracks where the dimensions are greater than the jig's. Hence the knobs on top and the flush far end.

Of course does just as well on smaller pieces ....

Peter


----------



## OPG3 (Jan 9, 2011)

Peter, that is in my opinion the single best way to make a dado cut! By the way, dadoes go across grain and grooves go along grain. When it is plwood I have no idea of the proper name! This jig can make dado and groove cuts. I've been using one like this for many years (mine is much simpler) and it never fails me - I just have to remember to always load my router with a 1/2" diameter bit (which is always smaller than the width I am routing). Your jig pictured here looks very nicely made! Keep-up the good work!


----------



## bobj3 (Jan 17, 2006)

http://www.routerforums.com/jigs-fixtures/2711-dado-jig-plunge-router.html

==


----------



## Greyone (Dec 24, 2010)

Very nice Peter, I assume the knobs are for adjusting to the size of the bit?


----------



## Aragocom (Jan 29, 2012)

Bill
No the jig always uses one particular bit - in this case a 5/16". The final step in setting the jig up before use is to run the router with the chosen bit down each rail to trim the inside face of the rail. As long as you use the same router bit and keep the same edge of the router against the same rail every time then the inside faces are always the extent of the cut. The router I am using here has two flat sides so it makes it easy.

The knobs are to there adjust the width of the cut - just drop what you want to fit into the groove between the rails, squeeze the rails together and tighten the knobs. Then line up the inside face on your line (with the groove on the correct side !), clamp and cut.

I looked at the one detailed in the link by bobj3 but the ability to just adjust to size and clamp to the line won the day - foolproof (well almost) with no calculations. As I said my router has two flat sides so I don't get jams and it also doesn't have provision for a guide bush.


----------



## 01stairguy (Apr 18, 2010)

nice job peter


----------



## jschaben (Jun 21, 2009)

Aragocom said:


> Bill
> No the jig always uses one particular bit - in this case a 5/16". The final step in setting the jig up before use is to run the router with the chosen bit down each rail to trim the inside face of the rail. As long as you use the same router bit and keep the same edge of the router against the same rail every time then the inside faces are always the extent of the cut. The router I am using here has two flat sides so it makes it easy.
> 
> The knobs are to there adjust the width of the cut - just drop what you want to fit into the groove between the rails, squeeze the rails together and tighten the knobs. Then line up the inside face on your line (with the groove on the correct side !), clamp and cut.
> ...


Hi Peter - That's a great jig. I made one a couple of years ago, just a bit different and I likely got the idea from BJ in the first place. Anyway, with several routers, having one particular router for use with the jig seemed to be a constraint. It doesn't take a lot of modification to use guide bushings as a reference surface rather than the base plate. That opens it up for use with any router and virtually any bit with the constraint being that you need to use the same bit/bushing offset combination you used for the final step. 
I've got it on my list of jigs I want to rebuild to incorporate a clamping system also.


----------



## Aragocom (Jan 29, 2012)

Thanks all

On reflection the side rails could be modified easily to use a guide bush. The router wouldn't be trapped - just guided so the same set the width / line up on the line would apply.

I also thought about two movable stops clamped to the fixed rail so that a stopped groove could be made

Peter


----------

