# Jig to cut housings with a chop saw



## londonman (May 1, 2010)

I tried searching as I guessed this might have been covered but no luck. Wrong search terms maybe.

I have a DW707 SCMS and although it has a depth stop, because it only has a single pivot point at the rear, this means that as you push/pull the chop saw the depth of cut in the housing increases as you push the saw away. So some sort of wedge under the bed would offer up the stock to make it parallel to the blade travel. Only trouble is that the angle would have to change each time you changed the depth of cut. So I was wondering if there were any jigs out there?

Before you all say 'dado' (!) I'm using the term loosely as I really want to use the saw to cut nice sharp tenon cheeks on a lot of 6 ft long door jambs. My chop saw bench is nicely set up to support the full length of the stock and to use stops to ensure consistency in the positioning of the cheeks and also ensure that the cheeks are nice 90 degree angles. Doing it on the table saw will be a tad difficult as having 6ft of stock flapping about isn't conducive to accuracy!


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## manumurf (Mar 4, 2010)

Rig up a cradle to hold the stock far enough away from the fence so that the lowest point of the blade travels at least past the back edge of the stock with the depth stop set. You might have to move it out an inch or two. I used to use my hitachi slider to do those types of cuts,


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## londonman (May 1, 2010)

Michael, that will prevent the curve of the blade from 'shaping' the cut nearest the fence but won't stop the cut getting deeper as the saw is pushed back towards the fence. I experimented today and set to a depth of about 1/2" the angle of the cut is 13 degrees. Dropping the blade closer to the bed, reduces the slope to 8 degrees.


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## manumurf (Mar 4, 2010)

The height of the blade from the table when moving the head in and out is not parallel to the table ( the same at it's outermost point as it is when pushed all the way in)? This is a sliding miter saw right?


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## londonman (May 1, 2010)

That's correct. Yes it is ..a Dewalt DW707.


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## manumurf (Mar 4, 2010)

http://images.toolstop.co.uk/product/DEW-DW707.jpg

Is that it?

Here's something from another, British sounding, hobby site.

Rob wrote:
> Decided that I needed to get on with those fiddly bits of wood, plinths
> and coving, to finish off my kitchen. Hired a DeWalt DW707 for the
> weekend for £32.

<snip>

> I might actualy by a mitre saw. Would anyone recommend the DW707 or
> should I go for extra features? Any other makes that I should consider?
>
> Thanks.
>

Yes. I have a DW707 and like it because its accurate, compact, robust
and not too heavy.

I fannied around with cheaper ones but the all ended up at the B&Q
returns counter because they were naff in one way or another … others
have had better experiences I might add. See http://tinyurl.com/78txc
and http://tinyurl.com/boydr for comments.

*The one thing you cannot do with a DW707 is trenching as the slide bars
do not remain horizontal during the plunge action*. It also has 3 (yes 3)
dust ports which is a little complex to connect up, but you get better
than average extraction from just 2 of them!

The slide action is not as long as some of the 254 mm jobs but it will
do a respectable 270mm by 60mm at 90 deg.

diytools.com had them at around £240 last time I looked, which is a
pretty good price.

I noticed that one of my local timber merchants uses them too.


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## londonman (May 1, 2010)

Yes, that is the model although mine is an earlier model and looks to have a better fence.

The thread you uncovered also highlighted the problem. So I was looking for any plans for an adjustable wedge shaped jig that I could slide underneath the workpiece thus raising it up to be parallel to the slide bars when adjusted to a trenching position. The need for an adjustable wedge is because the angle of the slide bars changes depending on the trenching depth.


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## manumurf (Mar 4, 2010)

If the amount of change varies with the distance of the saw from the fence on the outward pull then you are probably out of luck. If it is constant then just make a platform tilted the right amount.

You could make a scoring cut in the right position even though the depth is too shallow, then use a router and guide to clean out the rabbet.

Personally I would use my tablesaw and sliding table.


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## londonman (May 1, 2010)

For short stock I would as well. But these items are over 6ft long and so there is a tendency to whip around, drag and generally throw out the set-up.


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## uffitze (Apr 23, 2010)

sounds like it is time to use your hand tools.


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