Hello to all, first time here. How do I rip a tapered dado on my tablesaw? I have two 6in. by 4ft. pieces of plywood that I want to rip half-inch mirror-image dadoes in, basically from one corner to the opposite corner (diagonally). I tried to clamp a temporary fence to the table at the desired angle, to the blade, but I keep getting a parallel cut. I’m sure there is a simple solution, but I sometimes find those are the most difficult to figure out. Any help would be appreciated.
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fasten a 3/8x3/4 strip of wood to the ply to ride in the miter slot..
allow fer appropiate set backs
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Edited 12/27/2004 7:21 pm ET by IMERC
First of all, welcome. There is alot of good info to be had here so enjoy. If you can give an answer post it, if you wrong you'll find out fast.
If I were you I would clamp a board on the piece and use a router with a plywood dado bit. Thats my best guess. If i'm wrong i'll find out soon.
Good idea from IMERC. Bottom line is that the temp fence has to be attached to the workpiece, not the table saw fence. Anything attached to the saw fence will just continue to give you parallel cuts.
I'd use a router with say a quarter inch bit, in two passes, one for each side of the taper.Regards,
Boris"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
I would do it by making a taper jig sled, that would carry my workpiece against the fence and over the dado blade.
The taper jig sled would be a little different from the one I would use to cut tapers on square blanks of table legs, because the blade would be passing through and under the 90 degree vee joint of the sled that is pushing the back edge of the workpiece.
When I am ripping a taper, the rip blade is away from the sled. For this dado-plow scene, my jig would have to have enough beef at the tail end to tolerate the dado cut underneath.
first off, get your vernacular correct. It would be an angled dado, not a tapered dado...a tapered dado would change in width or depth over it's course.
carry on..safely.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
get your vernacular correct. It would be an angled dado, not a tapered dado...a tapered dado would change in width or depth
I'm thinking that a "tapered dado," in a textbook sense, would have to have a varying depth. Otherwise, it is not a parallel-sided cut in the "field" of a peice of stock.
I have no idea what a non-parallel, uniform depth, groove would be called, except maybe a trapezoidal rabbet (as you'd likely use a rabbeting plane in pre-mechanical days--where most of this terminology was created). Hmm, while trying to imagine what such a joint would be used for, the term "pinch dado" suggests itself.
The OP was on the right track, he wanted a "tapering jig" to make a dado at some angle on a sheet of ply. My thought would be to fit a piece of scrap on the panel-cutting jig, and fasten the workpiece to that in some fashion (double-stick, hot melt, pins, screws, whatever).
I would not use the #1 panel cutting jig, as the dado cutters are going to chew it up a bit in the fitting process. (Or, it'd be a good excuse to make a new, even more square, jig.)
I have to wonder if, maybe, the OP is making craftsman column surrounds, and maybe needs a rabbet in the compound mitre (which makes for a medium scary mental picture of 3/4" of dado head tipped over 38º something, and also cranked up to clear the table . . . I'm not even tough enough to picture a radial arm in similar circumstance [the flashbacks the flashbacks] <g>).Occupational hazard of my occupation not being around (sorry Bubba)
I make a dado for truss rods in guitar neck blanks that varies in depth only..from say 19 mm to 11mm over the length of the neck. That is accomplished by a sled and the blank is secured with flip type clamps, and shimmed for the taper. That dado is only 7mm widde tho.a sliding dovetail is tapered in the other plane..it can decrease in width so it only goes so far, and locks up.Given what the OP wants, I'd first use the router, if he has no router and insists on the TS method, then the ideas posted are the way.FYI..the dado blade is highly addicted to raw meat..I know of more WW's that got bit by those than a standard blade..mostly cuz the dado almost never has a guard around, and is not a thru cut where the blade is visabl from the top..thats why so many thumbs find it unexpectedly coming out of the edge of the board.Often on bookcase type work, dados are crosscut in narrow (relatively) boards..some think it's ok to use just the fence for registration...NO, NO, NO..A simple standard miter gage with an aux. (longer) fence screwed to it is the way..I sometime use 2 miter gauges with a rail connecting both.A panel jig is also indespensable for such stuff. but the blade is higher and chances of a FU are greater.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
plan "C"
tapered width dado...
cut conventional dado at the narrowest width and comp cut a shoulder or a spline on / into the intersecting piece......
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
works for me.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
plan "B"
tapered depth????
pass the ply thru on tapered guides...
do a conventional dado cut and taper / angle the insert piece to desired angle / pitch...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Tack or hot glue a 12" strip of ply to the piece you want to dado so that the 12" strip is parallel to the desired dado . Then the 12" strip rides against the saw fence and there ya go. cheers
...............Rik..........