LumberJocks

Question on cutting tapers on a table saw

  • Advertise with us

« back to Woodworking Skill Share forum

Forum topic by jsmit24 posted 07-12-2019 12:38 PM 1434 views 0 times favorited 96 replies Add to Favorites Watch
View jsmit24's profile

jsmit24

10 posts in 6 days


07-12-2019 12:38 PM

I’ve noticed that when I use a tapering jig on a table saw, the taper is uneven. More is taken off at the “bottom” of the cut than at the top. This is due to the blade being round. It’s alleviated to some extent when the blade is fully raised, but it’s still there on thick stock, such as a table leg.

So then how is any miter not affected in the same way to a much lesser extent?

It’s so pronounced on a taper jig that I started cutting tapers on my bandsaw. Has anyone else encountered this?

Thanks!


96 replies so far

View theart's profile

theart

105 posts in 972 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).

View Blindhog's profile

Blindhog

124 posts in 1466 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

View SMP's profile

SMP

1176 posts in 323 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

View bilyo's profile

bilyo

730 posts in 1520 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.

View pottz's profile

pottz

5547 posts in 1402 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.

-- sawdust the bigger the pile the bigger my smile-larry,so cal.

View theart's profile

theart

105 posts in 972 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.

View therealSteveN's profile

therealSteveN

3077 posts in 992 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

View pottz's profile

pottz

5547 posts in 1402 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

-- sawdust the bigger the pile the bigger my smile-larry,so cal.

View Ocelot's profile

Ocelot

2263 posts in 3056 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.

View a1Jim's profile

a1Jim

117652 posts in 3995 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

View jsmit24's profile

jsmit24

10 posts in 6 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!

View ChuckV's profile

ChuckV

3223 posts in 3945 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

View therealSteveN's profile

therealSteveN

3077 posts in 992 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

View Ocelot's profile

Ocelot

2263 posts in 3056 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

View Ocelot's profile

Ocelot

2263 posts in 3056 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

showing 1 through 15 of 96 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com