# What chisel for squaring up a 3/4" plywood dado?



## Dagobah (Aug 1, 2016)

Working on a project where I need to square up multiple 3/4" plywood dados made using a router and a undersized plywood bit. What size chisel should I use? This will be my first time using a chisel, so any tips (or brand recommendations) are welcome as well.


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## waho6o9 (May 6, 2011)

Router plane would make the dado flat and square, if I understand you

correctly.


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## Dagobah (Aug 1, 2016)

> Router plane would make the dado flat and square, if I understand you


This is for squaring up the end, where the router bit left a rounded edge.


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## MrFid (Mar 9, 2013)

So it seems like it's a stopped dado (that is, it doesn't continue all the way through to the front or back of the board), which means you're leaving a semicircular end on one or both sides. If that's the case, then a 1/4", or better yet a 3/8 inch chisel will do the trick for squaring the ends.

Tips: with a combo square or ruler and a knife (a razor blade will work fine if you don't have a marking knife) scribe your lines first before you start chiseling to prevent chipping out a piece or tearing out grain. Then tap your chisel into the knife line gingerly, then pare out to remove the waste. Repeat this process until you've achieved desired depth. Good luck!!


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## Loren (May 30, 2008)

You can use one of these.

http://www.rockler.com/corner-mortising-chisel?utm_source=google&utm_medium=cpc&utm_term=&utm_content=pla&utm_campaign=PL&sid=V9146&gclid=COWb4L24ztACFZU1aQodg_wK0g

or a 3/8" regular chisel would work well.


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## rwe2156 (May 7, 2014)

Once you get that figured out make sure you score the ply to get a nice neat job.


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## Dagobah (Aug 1, 2016)

> So it seems like it s a stopped dado (that is, it doesn t continue all the way through to the front or back of the board), which means you re leaving a semicircular end on one or both sides. If that s the case, then a 1/4", or better yet a 3/8 inch chisel will do the trick for squaring the ends.


Yes, this is exactly the problem. Thanks!


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## Dagobah (Aug 1, 2016)

> You can use one of these.
> 
> http://www.rockler.com/corner-mortising-chisel?utm_source=google&utm_medium=cpc&utm_term=&utm_content=pla&utm_campaign=PL&sid=V9146&gclid=COWb4L24ztACFZU1aQodg_wK0g


It's a 3/8" deep dado, can't tell if this would work well for that or not.


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## pintodeluxe (Sep 12, 2010)

When I make stopped dados, I usually notch the shelf (or tenoned part) so the dado is hidden. That way you don't need to square up the end of the dado.

If you do need to square it up, any bench chisel will work.


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## brtech (May 26, 2010)

Any kind of bench chisel will work, even the cheapo Harbor Freight plastic handle ones. It should be wide enough to enter the dado. I'd probably use my 1/2", even though it would be cutting both sides of the dado when used at the far end. I find that a wider chisel is easier to keep straight.

What would be very helpful is if the chisel was very sharp, which most new chisels aren't. Lots of advice here in LJs on how to sharpen a chisel. You can do it with sandpaper on your tablesaw top freehand, although a jig does help. A very sharp chisel makes this task very easy, and a dull one makes it hard and gets a sloppy result.

Using the scoring technique as MrFid suggests is really a good idea, especially if you will be able to see that joint on the finished piece. You may find it helpful to put a block of wood behind the chisel to help you keep it vertical, or even something with an L shape to hold it vertical and perpendicular to the dado.

For the first cut, you may be able to push down with your hands. The first cut determines what the surface will look like, so make it not too deep, like less than 1/4". You can use a mallet for most of it. Take smaller bites, and then pare the wood away from the inside unless it cuts easily with a mallet tap or two. Better to be a bit lower than the dado than have it stick up.


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## Dagobah (Aug 1, 2016)

> Any kind of bench chisel will work, even the cheapo Harbor Freight plastic handle ones. It should be wide enough to enter the dado. I d probably use my 1/2", even though it would be cutting both sides of the dado when used at the far end. I find that a wider chisel is easier to keep straight.
> 
> What would be very helpful is if the chisel was very sharp, which most new chisels aren t. Lots of advice here in LJs on how to sharpen a chisel. You can do it with sandpaper on your tablesaw top freehand, although a jig does help. A very sharp chisel makes this task very easy, and a dull one makes it hard and gets a sloppy result.
> 
> ...


Thanks, this was extremely helpful. I was hoping I'd be able to buy a sharp-ready chisel, but I suppose it's time I learned that skill as well.


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