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Question on cutting tapers on a table saw

by jsmit24
posted 07-12-2019 12:38 PM


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100 replies

100 replies so far

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theart

229 posts in 1433 days


#1 posted 07-12-2019 12:49 PM

This is due to the blade being round.

It shoudn’t matter that the blade is round, unless it’s significantly out of alignment with your fence or miter slots (whichever your jig is following).

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Blindhog

168 posts in 1927 days


#2 posted 07-12-2019 02:14 PM

Can you upload a pic of your taper jig/setup?

-- Don't let perfection get in the way of plenty good enough

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SMP

2636 posts in 784 days


#3 posted 07-12-2019 02:17 PM

Do you have a thin kerf blade? Sounds kind of like blade flex if i understand the description

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bilyo

1165 posts in 1981 days


#4 posted 07-12-2019 02:22 PM

If your blade is not vertical it will do that. Also, check to make sure your fence is parallel to the blade.

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pottz

11655 posts in 1863 days


#5 posted 07-12-2019 04:50 PM



If your blade is not vertical it will do that. Also, check to make sure your fence is parallel to the blade.

- bilyo


+1 a round blade has nothing to do with it.

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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theart

229 posts in 1433 days


#6 posted 07-12-2019 06:15 PM


+1 a round blade has nothing to do with it.

- pottz

It sort of does if the fence is diverging from the blade. If so, the front of the blade (bottom of stock) would be closer to the fence than the top edge of the blade (top of stock). Raising the blade all the way up would reduce the problem by bringing the top and bottom points closer together in the fore-aft direction. Of course, this would be a problem with all rip cuts, and not just tapers.

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therealSteveN

6432 posts in 1453 days


#7 posted 07-12-2019 07:41 PM



If your blade is not vertical it will do that. Also, check to make sure your fence is parallel to the blade.

- bilyo

Make sure the blade is actually 90* to the tables surface. Check that the blade is parallel to the miter slot, and or fence, depending on what you are following against. Something isn’t 90, and for a good taper things need to be 90. as in 89 starts making differences. If I had to guess I would say blade tilt.

-- Think safe, be safe

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pottz

11655 posts in 1863 days


#8 posted 07-12-2019 07:45 PM


If your blade is not vertical it will do that. Also, check to make sure your fence is parallel to the blade.

- bilyo

Make sure the blade is actually 90* to the tables surface. Check that the blade is parallel to the miter slot, and or fence, depending on what you are following against. Something isn t 90, and for a good taper things need to be 90. as in 89 starts making differences. If I had to guess I would say blade tilt.

- therealSteveN


+1 i agree

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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Ocelot

2618 posts in 3517 days


#9 posted 07-12-2019 07:57 PM

I’m wondering if you are using the taper jig in a different way than other people are.

The cut should always be parallel with the blade.

The piece being cut should be fixed in relation to the taper jig.

The taper jig and workpiece should slide as one.

The side of the taper jig should slide along the fence.

-- I intended to be a woodworker, but turned into a tool and lumber collector.

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a1Jim

118142 posts in 4456 days


#10 posted 07-12-2019 08:15 PM

If you are using the old style taper(see jig #1 )below one of the side boards may be bowed,If so i would suggest the newer sled style taper jig #2

#1

#2

https://www.artisticwoodstudio.com/videos

-- https://www.artisticwoodstudio.com/videos

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jsmit24

10 posts in 468 days


#11 posted 07-12-2019 09:02 PM

I am trying to balance what’s being said here with what I’m observing. I have a saw that is well set-up, sharp blade, etc. The taper jig itself is straight.

To me, it’s as simple as this… and maybe I just need to be “straightened out,” but imagine you’re tapering a 3” leg… something with some heft. You’re moving into your blade. Contact is made first with the part of the leg that’s against the table. How much further do you have to push your piece until the top of the blade makes contact? That’s where the unevenness comes in. The taper begins at “blade zero” at the bottom of the cut and at “blade zenith” at the top of the cut. In between initial contact with the bottom of the blade and initial contact with the top of the blade, the piece has moved a couple of inches. Rub a little finish on a piece before tapering it. Make sure the piece is thick. Then tell me if you’re seeing even removal of the finish at the beginning of the cut.

I’m not arguing with anyone here… it may be me that’s wrong. Maybe there’s a problem in the setup between my own ears… my wife says there is… but I’m just explaining what I think are the physics of the blade on a taper.

Thanks!

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ChuckV

3333 posts in 4406 days


#12 posted 07-12-2019 09:18 PM

Based on your explanation, it seems that maybe you have the jig fixed and are sliding the board along it. Look at what Ocelot wrote above in #9.

-- “Big man, pig man, ha ha, charade you are.” ― R. Waters

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therealSteveN

6432 posts in 1453 days


#13 posted 07-12-2019 09:27 PM

Only takes a minute to recheck the 90 of the blade with a combination square, and then run it in the miter slot to check against the blade, if the blade is good scoot the fence over to the close miter slot. Miter slots don’t move, so if the blade side is good, the fence side will be too.

You have gotten several responses saying check this, no kidding here, your TS is not 90* square, some direction it’s off.

If you find this to be a fact, it may take a little bit to make it right. Don’t sweat that, you will instantly become safer, and your work will improve once you either shift your table, or if you are lucky all you will need to do is fix that indicator which is off saying you don’t have any tilt. I think you do. Maybe realign your fence. It’s one of them, or you would note the bend in the taper jig.

-- Think safe, be safe

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Ocelot

2618 posts in 3517 days


#14 posted 07-12-2019 10:14 PM

Without pictures, we can only guess what you are doing and what the problem may be.

Posting pictures on LJ is very easy.

-Paul

-- I intended to be a woodworker, but turned into a tool and lumber collector.

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Ocelot

2618 posts in 3517 days


#15 posted 07-12-2019 10:21 PM

Here’s a writeup on posting photos I did a couple years ago. I don’t think anything has changed.

https://www.lumberjocks.com/Ocelot/blog/110921

-- I intended to be a woodworker, but turned into a tool and lumber collector.

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jsmit24

10 posts in 468 days


#16 posted 07-12-2019 11:15 PM

Everything is square, guys. And no, I’m not moving the piece along the taper jig.

Here are some photos. First, here’s “proof of square.”

Then a picture of my taper jig on my square-checked fence.

Some finish rubbed onto my thick piece of scrap stock:

And the resultant cut:

Notice how that curvature roughly looks like the curvature of the blade? Now I’m no physicist, but the bottom of the cut makes contact sooner and your workpiece is moving. This isn’t to do with my saw, it’s to do with the blade being round. This doesn’t happen on a bandsaw. Someone try this in your own test and tell me if you get different results, please… on a thick piece of stock where the curvature of the blade comes into play.

Again, I very much appreciate the opinions of everyone who has responded, and conflict is not my objective. Believe me, I’m used to admitting when I’m wrong, and would love the opportunity to do so here in this case as well!

Thanks!

Thanks!
Jeff

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a1Jim

118142 posts in 4456 days


#17 posted 07-12-2019 11:42 PM

Jeff the angle style taper jig relies on your fence,if you fence is bowing then you can get the results your showing.
With a sled style taper jig, it runs in your miter groove so you don’t need to rely on a flexible fence.

https://www.lumberjocks.com/projects/84728

https://www.artisticwoodstudio.com/videos

-- https://www.artisticwoodstudio.com/videos

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Madmark2

1701 posts in 1467 days


#18 posted 07-13-2019 12:13 AM

Your explanation is incorrect. Sight the blade and it is a straight verticle line. This is the cut line and it matters not that the bottom of the blade starts first. The piece is moving parallel to the fence and as long as the piece is pushed all the way thru the start point matters not.

Now if anything isn’t square (the edges of the workpiece, the fence, blade, etc. ) then you get that result. In the example pic the end wasn’t smoothly cut and the taper followed the uneven edge. Square cut first and the variance will vanish. Always take a thin square trim cut. Lots of store bought S4S ain’t square.

You can prove that the top is trimmed at the same point as the bottom by drawing a line, setting the leading edge of the blade to the line and seeing the cut isn’t curved. If you can’t get that result then you have something wrong in your gear, set up or technique.

M

-- The hump with the stump and the pump!

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jsmit24

10 posts in 468 days


#19 posted 07-13-2019 02:18 AM

Okay. Maybe I’m incorrect, and I’m just going to drop it. I know the part of the cut that is a through cut is straight… it’s the very beginning of the cut that suffers. You can watch almost any tapering jig video on YT and see the shape of the offcuts have that little arc at their thinnest part. Not one video, but many. The first contact is at the bottom. The through cut doesn’t begin until another inch or three. Once the through cut begins, everything is fine.

Maybe it was a bad question… or maybe it’s a little thing that just doesn’t show up. Still… next time you’re making one of those cuts… check me out. Anyone that can show me a straight line at the start of the taper, I’ll buy ‘em a coffee. :-)

Thanks for all the feedback, guys!

Jeff

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GrantA

2894 posts in 2286 days


#20 posted 07-13-2019 02:22 AM

Sand it to get rid of saw marks and the problem will disappear
Problem solved, have a beer. Cheers!

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pottz

11655 posts in 1863 days


#21 posted 07-13-2019 02:54 AM



Sand it to get rid of saw marks and the problem will disappear
Problem solved, have a beer. Cheers!

- GrantA


CHEERS!

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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clagwell

311 posts in 671 days


#22 posted 07-13-2019 10:23 AM

I think what you are seeing is indeed caused by blade curvature but it’s not the curvature you think. Side forces can cause the blade to take on a dish shape. This effect is usually called blade deflection. The shallow angle of the taper causes this side force to be the only force on the blade when the material first touches the it. Once the blade is fully surrounded by wood the side force imbalance changes. The result is a bit of wandering of the cut in the first part of the taper as the amount of deflection varies over the length of the cut.

The same thing can also happen in a skimming cut but is not nearly as obvious without the magnifying effect of the taper.

The deflection will be worse with a thin kerf blade as well as with dull teeth.

Actually, what you are getting is not too bad. The shallow taper angle amplifies the visual difference. If you put a straightedge along the cut, top and bottom, I think you’ll only see a few mils if curvature.

Pardon me for asking the obvious question, but why are you using a tapering jig on the rip fence? When I got my slider the tapering jig was the second thing to give up it’s storage space, right after the sled.

-- Dave, Tippecanoe County, IN --- Is there a corollary to Beranek.s Law that applies to dust collection?

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Peteybadboy

2318 posts in 2828 days


#23 posted 07-13-2019 11:20 AM

I put a screw in the Stop that holds the leg. The screw will not let the leg move in the jig. (look at a1Jim) photo. See the stop, put a sharp screw through it, to hold the leg in place.

-- Petey

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Dusty56

11859 posts in 4567 days


#24 posted 07-13-2019 01:52 PM

Is the pictured blade the one you use for ripping your tapers? It looks like a combination blade used for rough framing purposes. You might want to invest in a quality ripping blade, and definitely get rid of that tapering jig. You can build a tapering sled for not a lot of money and also use it to cut a straight edge on crooked boards.
I also know what you’re talking about, and unless the arc of your blade is high enough to come in contact with the center of the thickness of your material, you will have a slightly offset cut at the very beginning of the taper. Obviously as you push the piece forward, you would be engaging more of the blade, thus creating full surface contact and an even cut. A simple hand plane would remove that bothersome issue of yours in one or two passes at the most. : )

-- I'm absolutely positive that I couldn't be more uncertain!

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bilyo

1165 posts in 1981 days


#25 posted 07-13-2019 03:20 PM

You are putting far too much emphasis on the fact that your blade is circular and that your taper cut begins with the teeth closest to the table. Of course it does. But this has nothing to do with the results of the cut. As long as your blade is vertical and your fence, blade, and miter slot are parallel, your results will be a straight vertical cut.
Looking at your last photo, I assume the the brown part on the left is the original surface and the light color on the right is the fresh cut. The resulting curved line between them has nothing to do with the blade. It is the result of the original surface not being flat and square to the bottom surface of the work piece. Check it with a square to see if that is true. If you make sure that the original surface is flat and square before starting and then make your taper cut, you will then end up with a vertical line where they meet. If it will help you visualize this, start out with a profiled edge (use your router and most any profile bit). Then cut your taper through the profile. You will not get a straight line where they meet, but a crooked line that shows where the profile surface and the flat surface meet.
Hope this helps.

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MrRon

5940 posts in 4122 days


#26 posted 07-13-2019 04:12 PM

If you are just starting a “skim” cut (the right side of the blade doing the cutting), The blade will deflect to the left until the blade is making it’s full kerf cut. After that, the blade will settle down to it’s no deflection cut. Try feeding the work into the blade very slowly to make sure the blade is cutting (not rubbing).

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pottz

11655 posts in 1863 days


#27 posted 07-14-2019 12:16 AM



You are putting far too much emphasis on the fact that your blade is circular and that your taper cut begins with the teeth closest to the table. Of course it does. But this has nothing to do with the results of the cut. As long as your blade is vertical and your fence, blade, and miter slot are parallel, your results will be a straight vertical cut.
Looking at your last photo, I assume the the brown part on the left is the original surface and the light color on the right is the fresh cut. The resulting curved line between them has nothing to do with the blade. It is the result of the original surface not being flat and square to the bottom surface of the work piece. Check it with a square to see if that is true. If you make sure that the original surface is flat and square before starting and then make your taper cut, you will then end up with a vertical line where they meet. If it will help you visualize this, start out with a profiled edge (use your router and most any profile bit). Then cut your taper through the profile. You will not get a straight line where they meet, but a crooked line that shows where the profile surface and the flat surface meet.
Hope this helps.

- bilyo


+1 I agree the round blade argument doesn’t work.for taper cuts I never use a thin kerf blade for the reason it will deflect with side pressure which a taper cut will cause.

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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bilyo

1165 posts in 1981 days


#28 posted 07-14-2019 01:11 AM

I cannot offer any proof to the contrary, but logically I am not convinced that cutting a taper on the table saw using a taper jig puts any significant side pressure on a sharp blade that is correctly set up. At the beginning of the cut there might be a very small sideways force component on the blade only because it is not cutting evenly on both sides. However, I don’t think it would be enough to cause the problems that the OP is describing. Remember, even though the work piece is at an angle to the blade, it is being fed into the blade along a line in line with it. Again, assuming the conditions above, there should be only very very minor side forces at the beginning of the cut. I frequently fine tune the length or width of a work piece by taking a very narrow cut of 1/2 a blade width or less. I have no problem getting a square cut this way with no (noticeable) deflection on a thin kerf blade.

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Lazyman

5857 posts in 2266 days


#29 posted 07-14-2019 03:44 AM

If you have eliminated squareness as an issue then it has to be the blade is deflecting or the taper jig is flexing or pivoting due to sideways pressure or the piece is somehow moving ever so slightly in the jig as you start the cut. It could also be possible that the riving knife is deflecting slightly or is out of alignment with the blade or is not at 90° in which case the problem is caused at the back side of the blade rather than the front.

Have you tried making a second pass to see if that cleans it up or even stopping the cut just as the blade is fully engaged vertically to see how it looks then?

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

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jsmit24

10 posts in 468 days


#30 posted 07-14-2019 04:35 AM



I think what you are seeing is indeed caused by blade curvature but it s not the curvature you think. Side forces can cause the blade to take on a dish shape. This effect is usually called blade deflection. The shallow angle of the taper causes this side force to be the only force on the blade when the material first touches the it. Once the blade is fully surrounded by wood the side force imbalance changes. The result is a bit of wandering of the cut in the first part of the taper as the amount of deflection varies over the length of the cut.

The same thing can also happen in a skimming cut but is not nearly as obvious without the magnifying effect of the taper.

The deflection will be worse with a thin kerf blade as well as with dull teeth.

Actually, what you are getting is not too bad. The shallow taper angle amplifies the visual difference. If you put a straightedge along the cut, top and bottom, I think you ll only see a few mils if curvature.

Pardon me for asking the obvious question, but why are you using a tapering jig on the rip fence? When I got my slider the tapering jig was the second thing to give up it s storage space, right after the sled.

- clagwell


I would love to hear about how you cut a taper on your slider. I’ve seen the Fritz and Franz setup and there’s a modification to that design that would facilitate tapers. What started all this “problem” was the desire to make a flag case for my recently deceased father-in-law, who served in the USAF and therefore received the flag as a military honor at his services. So… I need to make a 22-1/2 degree miter. I’ve seen George Vondriska and others who make these flag cases and they always use a vertical cut (piece standing on end with the blade angled to 22.5 degrees). My first thoughts were 1) I don’t have a jig for that and I’d have to make one. No big deal… and 2) but why couldn’t I just cut a taper?

When I got my resultant cut, I formed my “round blade theory”—it’s kinda like the “flat earth society”, where one finds themselves in an extreme minority. :-) And I started back to make the vertical jig. And in the meantime, I posted my “round blade theory” here.

SO… I’d be very interested in seeing or hearing about how you would approach a 22-1/2 degree miter on 1-1/2” thick stock. I did clamp a makeshift guide to my slider that approximated the 22-1/2” angle and cut some MDF as a trial… so I know I could go that way… but making it precise is a different matter.

Thanks!
Jeff

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therealSteveN

6432 posts in 1453 days


#31 posted 07-14-2019 05:50 AM

Make a tall tenon jig, a router sled, or a panel cutting jig for the table saw. All of them are essentially something you run over. or along the fence, and set your rip fence so you cut off a straight line. Actually making tall bevel cuts is easier than making a tenon. With the tenon you need to measure meticulously to get just the right width. For your bevel all you need is an accurate way to measure blade tilt. Something like a Wixey cube allows for this. You will be cutting both a 45 and 2, 22.5 angles.

After you have set the blade tilt, all you need to do is move the fence over until it is right on the blade, without actually touching it. I’d start with some trial scrap, as it is different. Having a clamp on the board will assure it doesn’t move, which will mess up a crisp edge. It’s a straight through cut, the tilt, and the fact you aren’t letting the board move make for a nice bevel cut.

Any of the jigs will be something that you can do double duty with, and it will get used again.

In case you can’t see the router sled working, it's right here. Just stand it up.

Using a taper jig would be a last choice as they just aren’t made to measure in degrees, just a half inch, inch, whatever consistent overhang you want. For that accurate tilt angle you need it to be the blade itself, and moving the stock through the blade must be held securely, no movement.

-- Think safe, be safe

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MrRon

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#32 posted 07-14-2019 09:22 PM

I’m wondering if you can feed the tapering jig and wood through the saw in reverse; that is starting the cut at the exit end where the full kerf of the blade enters the wood and exits at an angle. You would have to make sure the wood would be fully in contact with the tapering jig, or a kickback could happen. Another thing you could try is to apply a scrap piece of wood with double stick tape to the leg at the start of the cut. That way, the leg would see the full kerf of the blade, eliminating any possible deflection.

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MrRon

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#33 posted 07-14-2019 10:24 PM

Reply deleted

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theart

229 posts in 1433 days


#34 posted 07-15-2019 01:14 PM


I cannot offer any proof to the contrary, but logically I am not convinced that cutting a taper on the table saw using a taper jig puts any significant side pressure on a sharp blade that is correctly set up. At the beginning of the cut there might be a very small sideways force component on the blade only because it is not cutting evenly on both sides. However, I don t think it would be enough to cause the problems that the OP is describing. Remember, even though the work piece is at an angle to the blade, it is being fed into the blade along a line in line with it. Again, assuming the conditions above, there should be only very very minor side forces at the beginning of the cut. I frequently fine tune the length or width of a work piece by taking a very narrow cut of 1/2 a blade width or less. I have no problem getting a square cut this way with no (noticeable) deflection on a thin kerf blade.

- bilyo

To be fair, nobody claiming blade deflection has offered any proof that the phenomenon exists as they understand it either. Lateral deflection in a spinning blade is a highly complex dynamic behavior. Most of the research work done on blade deflection is really concerned with vibrational amplitude, which is of consequence for surface quality. It’s not anywhere near the same as pushing on the side of a stationary blade and seeing how much it moves.

Regardless of how much lateral force is being applied to the blade (which even in a cove cut is minimal relative to its stiffness), getting the blade to lean to the side requires what’s called a “standing wave”. This basically means that the wave speed of one of the vibration modes matches the rotation speed of the blade, and the natural frequency effectively drops to 0Hz. The speed at which this occurs depends on blade thickness, density, modulus, and a little bit on lateral perturbations but not much. Typically, the 0,3 mode (three full sine waves around the blades perimeter) has the lowest critical speed, but it’s going to be significantly faster than most saw motors. The mode that’s being pictured when most people describe deflection would be called the 0,1 mode (one full sine wave around the perimeter), which does not form a standing wave under any conditions.

Until I’ve seen some experimental data to the contrary, I generally assume that everything in my setup is deflecting except the blade.

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Robert

4035 posts in 2359 days


#35 posted 07-15-2019 02:00 PM

Tapering a leg is a “get it close/dial it in” type task. You won’t get a finished surface off the blade so the surface has to be dressed. You can easily take care a minor discrepancy like the one you illustrate.

In the same vein, I would like to say a lot of time can be wasted and frustration had by taking a machinist approach to ww’ing. Same thing with guys who strive for “off the machine” results.

A hand plane a ww’ers best friend. That’s 30 years of ww’ing speaking…..........

-- Everything is a prototype thats why its one of a kind!!

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theart

229 posts in 1433 days


#36 posted 07-15-2019 02:13 PM



Tapering a leg is a “get it close/dial it in” type task. You won t get a finished surface off the blade so the surface has to be dressed. You can easily take care a minor discrepancy like the one you illustrate.

In the same vein, I would like to say a lot of time can be wasted and frustration had by taking a machinist approach to ww ing. Same thing with guys who strive for “off the machine” results.

A hand plane a ww ers best friend. That s 30 years of ww ing speaking…..........

- Robert

Leg tapers also usually fall into the “non-mating surfaces” category. If they look good, they are good.

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bilyo

1165 posts in 1981 days


#37 posted 07-15-2019 03:32 PM

I wonder if the OP feels like he has an answer to his original question.

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therealSteveN

6432 posts in 1453 days


#38 posted 07-16-2019 01:17 AM

I have to apologize. I fear I may have runt him off… First I was certain he had some issue with blade, or fence alignment.

Probably would be best to start with watcha trying to do?????

I never saw making a flag box come out of a taper jig. But it is a taper, so in my limited mindset, maybe I just needed to figure out how to know what degree to cut at?

I hope he succeeds in his endeavor, and does so safely.

-- Think safe, be safe

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jsmit24

10 posts in 468 days


#39 posted 07-16-2019 03:51 AM

No one has ran me off here. I much appreciate all the constructive ideas. I probably didn’t do a great job at getting my original point and purpose across. My opinion has been challenged by almost everyone, and those challenges have caused me to do some more thinking… and that can’t be a bad thing… so thanks, and I’m not “gone,” just trying to figure a good way to make these cuts, still.

Thanks!
Jeff

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BuckeyeDennis

93 posts in 577 days


#40 posted 07-16-2019 10:44 AM


No one has ran me off here. I much appreciate all the constructive ideas. I probably didn t do a great job at getting my original point and purpose across. My opinion has been challenged by almost everyone, and those challenges have caused me to do some more thinking… and that can t be a bad thing… so thanks, and I m not “gone,” just trying to figure a good way to make these cuts, still.

Thanks!
Jeff

- jsmit24

A Google search didn’t turn up any examples of such a jig, but it struck me that a taper jig on a jointer should be able to accurately machine your acute miter joints. The idea is really no different than using a shooting board and a hand plane — just a different tool. You still need to make a rough cut, and then dress it with the jointer.

The jig is nothing more than a wedge to which you can clamp your workpiece. The wedge angle could be either fixed or adjustable. To use it, just lower the jointer infeed table out of the way, and run the jig on the outfeed table only. As the workpiece passes over the cutterhead, the joint will be machined coplanar with the bottom of the jig.

BTW, when it comes to explaining your table saw tapering inaccuracy, I’m in the blade-deflection camp. Several months ago, I spent a lot of time trying to eliminate “snipe” on the both ends of a straight-line rip with a Makita track saw. I tested and controlled for any and all static alignment variables that I could identify, but still couldn’t eliminate the snipe during blade entry and exit. I finally found a YouTube video where a guy had a similar problem, and solved it by replacing the blade. So I replaced my pristine stock Makita blade with a Festool blade, and got much better results. And then I bought a Forrest blade with a thicker plate, and the snipe was reduced to 0.002” or less. Nothing else changed in the tests — just the blades.

A jointer is far more rigid than a saw blade, so I’d expect the cut accuracy to be commensurately better.

-- Dennis 'We are all faced with a series of great opportunities, brilliantly disguised as impossible situations.' Charles Swindoll

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bilyo

1165 posts in 1981 days


#41 posted 07-16-2019 05:58 PM



No one has ran me off here. I much appreciate all the constructive ideas. I probably didn t do a great job at getting my original point and purpose across. My opinion has been challenged by almost everyone, and those challenges have caused me to do some more thinking… and that can t be a bad thing… so thanks, and I m not “gone,” just trying to figure a good way to make these cuts, still.

Thanks!
Jeff
- jsmit24


You have gotten lots of good advice above. Any conflicting info, I think, is due to not fully understanding what your are trying to achieve. If you could fully explain what you are doing, we might be able to be more helpful.

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theart

229 posts in 1433 days


#42 posted 07-16-2019 07:12 PM

I m not “gone,” just trying to figure a good way to make these cuts, still.

I think you could do four legs Robert’s way (rough cut on the table saw and clean up with a hand plane) in less time than it took to read this whole thread.

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jsmit24

10 posts in 468 days


#43 posted 07-16-2019 07:37 PM



I m not “gone,” just trying to figure a good way to make these cuts, still.

I think you could do four legs Robert s way (rough cut on the table saw and clean up with a hand plane) in less time than it took to read this whole thread.

- theart


Well… if you read the thread, you’d know that cutting tapers on legs was just an illustration. That’s not what I’m attempting to do. 22.5 degree miters for a flag case were the objective.

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pottz

11655 posts in 1863 days


#44 posted 07-16-2019 10:02 PM


I m not “gone,” just trying to figure a good way to make these cuts, still.

I think you could do four legs Robert s way (rough cut on the table saw and clean up with a hand plane) in less time than it took to read this whole thread.

- theart

Well… if you read the thread, you d know that cutting tapers on legs was just an illustration. That s not what I m attempting to do. 22.5 degree miters for a flag case were the objective.

- jsmit24


maybe be a little clearer next time to save everyone a lot of wasted time giving the wrong advise.

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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Charlie H.

405 posts in 1529 days


#45 posted 07-17-2019 01:52 AM

I see exactly what you are talking about. The circular blade does enter the cut closest to the table top first so mark that as point A as the wood is pushed farther into the cut the wood at the table top travels some distance before the blade exits the cut at the top so mark that as point B. The only way to minimize that is (as you noted) to raise the blade high enough that the blade enters the top of the wood at the same time as it enters the bottom of the wood.

-- Regards, Charlie in Rowlett, TX --------I talk to myself, because sometimes I need expert advice.---------

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jsmit24

10 posts in 468 days


#46 posted 07-17-2019 03:57 AM



I see exactly what you are talking about. The circular blade does enter the cut closest to the table top first so mark that as point A as the wood is pushed farther into the cut the wood at the table top travels some distance before the blade exits the cut at the top so mark that as point B. The only way to minimize that is (as you noted) to raise the blade high enough that the blade enters the top of the wood at the same time as it enters the bottom of the wood.

- Charlie H.

Bingo! And if the stock is so thick that you can’t make a full through cut, then you’re not going to have a successful miter. I used a taper on a leg as an illustration of this, and I think it caused confusion. But what you’re saying is exactly the point I was making as well. And my original question does in fact have an answer, and of course, it’s just what you said. There’s none of this issue on a thru-cut.

Thanks!
Jeff

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bandit571

26710 posts in 3562 days


#47 posted 07-17-2019 04:11 AM

Hmm…

Meet the Stanley #2246 Miter Box….this one is set at 19 Degrees to cut the angles for a porch’s step handrails..

That 22-1/2 degree setting is already marked on this saw…Sometimes, you just have to use a bit of math

0 – 19 = 71 degrees….0 = 90 degrees. Or, just swing over to the notch needed, and make the cut.

-- A Planer? I'M the planer, this is what I use

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therealSteveN

6432 posts in 1453 days


#48 posted 07-17-2019 04:42 AM

A person could use a meat powered miter box, or a motorized one as well, if you trust it to be 22.5 degrees I had an Ulmia 354 I would trust. Sold it, dummaz I am. It would do a 22.5 in a heartbeat.

Standing it up to run across a TS blade tilted to 22.5 degrees is how I have done that. Any of the TS jigs that will support a tall panel will work, and most only take some scrap plywood, and an hour or two to perfect.

Who posted you could have tapered 4 legs of a table, and all 3 miters on a flag box in the time it takes to read this. Is probably getting close.

-- Think safe, be safe

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Robert

4035 posts in 2359 days


#49 posted 07-17-2019 02:59 PM


I see exactly what you are talking about. The circular blade does enter the cut closest to the table top first so mark that as point A as the wood is pushed farther into the cut the wood at the table top travels some distance before the blade exits the cut at the top so mark that as point B. The only way to minimize that is (as you noted) to raise the blade high enough that the blade enters the top of the wood at the same time as it enters the bottom of the wood.

- Charlie H.

Huh???

My other “huh??” is now it appears the poster is talking about a miter not a taper. Regardless, it can all be done on a table saw and the cut will be even and perpendicular to the face as long as the saw is aligned to 90° and you’re using a decent quality machine.

IOW if the blade is perpendicular the cut will be even across the miter. Where the blade enters the wood is irrelevant.

Is a mountain getting made of a mole hill or am I missing something?

-- Everything is a prototype thats why its one of a kind!!

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pottz

11655 posts in 1863 days


#50 posted 07-17-2019 03:26 PM


I see exactly what you are talking about. The circular blade does enter the cut closest to the table top first so mark that as point A as the wood is pushed farther into the cut the wood at the table top travels some distance before the blade exits the cut at the top so mark that as point B. The only way to minimize that is (as you noted) to raise the blade high enough that the blade enters the top of the wood at the same time as it enters the bottom of the wood.

- Charlie H.
Huh???

My other “huh??” is now it appears the poster is talking about a miter not a taper. Regardless, it can all be done on a table saw and the cut will be even and perpendicular to the face as long as the saw is aligned to 90° and you re using a decent quality machine.

IOW if the blade is perpendicular the cut will be even across the miter. Where the blade enters the wood is irrelevant.

Is a mountain getting made of a mole hill or am I missing something?

- Robert


+1 this round blade theory just doesn’t make any sense.maybe im missing something too? your making a staright cut,just angling the work piece.this isn’t rocket science.

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

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