Coping on the TS

[Jack Frederick]

I have a couple pieces of Sapele 72x13x1-9/16 I am making a couple pedestal benches to match a dining room table I built for my daughter. I want to relieve or shape the bench to be a bit more of a comfortable seat. My original intention was to run the track saw the length of the benches to create the lines of depth and then go after it with planes, inshaves etc. Got thinking of it and perhaps the table saw is the right method. Any suggestions on coping, blade type etc. I get the basic idea but have not done this operation before. I have the 3hp SS. Much obliged for any suggestions.

[Nike Nihiser]

I saw a video, don't know where, that showed a guy who suspended a router like a pendulum to rout a recess in a bench. You just need to get the arc you want on the pendulum.

[Jim Becker]

Doing a bench seat like this with an angled auxiliary fence in the same way one might do crown cove molding wouldn't been too difficult. You can use almost any blade and I'd use whatever I had on the saw which for me is pretty much my Forrest WW-II. You are not creating the 'finished' surface here and will need to work it further afterward, especially for a seat where you might vary the angle and so forth for an asymmetric relief pattern. Take. Your. Time. Doing this, both for safety and to work out the changes in angles, and so forth to get the end result you want. Have a shorter test piece of the same width to work with that has the profile you want drawn on the ends so you can always test each cut change before moving on to the next.

Alternatively, you can do this with a guided router that you move laterally for each pass as you vary the depth to hog out the material.

[Peter Christensen]

As Jim said most any blade you have will work and if you were doing a lot of cove cutting there are special blades you can get for the job too but they are 7" and won't work in a SawStop. If you can track down a 8" version it would work with the dado brake. If you have a good saw sharpening service near you you could have them reshape the teeth to have rounded tops. The reason to to that is to make a smoother cut to reduce the sanding especially for narrow coves. Not worth it if you are only coving occasionally.

https://www.amazon.com/CMT-235-006-0.../dp/B000P4JP66

https://sommerfeldtools.com/cove-cut...rved-cabinetry

Here are a couple calculators that may be of use to you.

https://woodgears.ca/cove/calculate.html

https://woodgears.ca/cove/asymmetric.html

[Lee Schierer]

I generally curve the slat supports and leave the slats flat, to make the seat more comfortable. Coved slats would be too narrow to create a comfortable conjure for a seat.

[John K Jordan]

Doing a bench seat like this with an angled auxiliary fence in the same way one might do crown cove molding ...
Alternatively, you can do this with a guided router that you move laterally for each pass as you vary the depth to hog out the material.

If I understand correctly, I used to do this with a radial arm saw - angle the blade instead of the fence. I always used spring hold-downs to keep the board tight against the fence and the table. But always small coves, never wide enough for a bench, single pass and usually in pine.

I guess 72" long is a bit cumbersome for the CNC, huh? Or maybe that would be cheating.

Sounds like this is going to be a beautiful table/bench combo. Pictures will be required!

JKJ

[Jack Frederick]

I got this all set up, fence in/outfeed and slowly went at it. The saw was freshly waxed to keep down the friction. I did about 1' of one of the first piece and stopped. The cut portion came out pretty well. It was just to hard to feed and I didn't like pushing laterally on the blade. The blade projection was about 5/16". The dust collector handled the saw part ok once I put a block over the exposed end of the cut, but boy it put up a cloud in those first few inches of cut. I took the sawhorses outside and did most of the rough profiling outside with the router & 3/4 round nose bit. It was best to do this outside just from a shop cleanliness stand point. Respirator required. From there I took off some of the high spots with planes. There is a lot of work to do on both of these but they come together. Have you had any luck with the convex wheels on a grinder for rough shaping, more of a sanding profile rather than a hog? Which ones?

[Edwin Santos]

I got this all set up, fence in/outfeed and slowly went at it. The saw was freshly waxed to keep down the friction. I did about 1' of one of the first piece and stopped. The cut portion came out pretty well. It was just to hard to feed and I didn't like pushing laterally on the blade. The blade projection was about 5/16". The dust collector handled the saw part ok once I put a block over the exposed end of the cut, but boy it put up a cloud in those first few inches of cut. I took the sawhorses outside and did most of the rough profiling outside with the router & 3/4 round nose bit. It was best to do this outside just from a shop cleanliness stand point. Respirator required. From there I took off some of the high spots with planes. There is a lot of work to do on both of these but they come together. Have you had any luck with the convex wheels on a grinder for rough shaping, more of a sanding profile rather than a hog? Which ones?

Were you taking off 5/16" in a single pass??

I've done plenty of cove cutting, and never taken more than 1/16" or maybe 3/32" in a single pass. Anytime the work is hard to feed, the tooling it telling you something.
Cove cutting can be dusty, but keeping it to light passes will help your dust collector keep up with it.

This said, if I understand your objective properly, I can't see where a cove cut on the table saw would be wide enough for a hollow for a seat bench. Maybe a better approach would be some of the suggestions above such as curved supports or multiple passes with a router followed by hand tools.

[johnny means]

I think you're on the right track with the grooving then clean up method. It's going to get you the exact profile you want in a very straight forward predictable way. Coving on a table saw is a lot of trial and error if you don't have some sort of software to use to preview the arcs you'd be cutting. Also, you're limited to the radius of your sawblade, which doesn't strike me as a useful option in this situation.

[Kevin Jenness]

Before I had a CNC router I did several benches like these using multiple stepped passes with a dado head and sliding table saw to rough out the coves followed by round bottom plane and sanding blocks. Tedious but effective. It sounds like your application would be along the seat length, using the rip fence.easternpinebench1500px.jpg

[Jack Frederick]

Ok, based upon your excellent advise I set up the cove again yesterday. Essentially I had a multi grooved board with Edwins advise kept the cuts very thin and every thing went smoothly. Certainly a lot of finish shaping to do but a pretty good base to work off. Much obliged.

[Tom Bender]

Your approach with the router is good. Here's an improvement;

Make a baseplate for your router 18" x 18" center the bit 4" from one side. Attach an adjustable stop along the opposite side to guide along the edge of your stock. Add a 2x4 across the middle for a handle.

[Al Launier]

How about pictures during & when completed?

[Jack Frederick]

How about pictures during & when completed?

There are probably simpler and certainly faster ways to do this once I finished with the router and TS. I have people who stop by sit and comment on the comfort of the profile I’ve been cutting. Good thing I’ve asked. One thing I have found all ready is that bench is perfectly comfortable for a nap now. The daughter for whom these are being built will be up tomorrow, so I should have the final answer on fit then. I have heard that you can actually post pictures. I’ll get some help on that.

[John K Jordan]

... I have heard that you can actually post pictures. I’ll get some help on that.

Put the cursor where you want the picture in the message and click on this:

post_photos.jpg

In the dialog box that comes up choose From Computer, click Browse, then find the file on your computer and click Open. This will return you to the dialog box click Upload File. If you don't see all this you may be in the Mobile mode - I don't know about photos from there. Click "Full Site" at the bottom center of any screen to switch to the non-mobile version of SMC.

BTW, a very large photo may or may not upload. I like use an image editing program to reduce the size (pixel dimensions) some and perhaps crop, etc., then save as a JPG file with a fair amount of compression (not the highest quality). The lower quality will make a smaller file and the image won't noticeably suffer.

JKJ