Making Cove Molding on Wood Works

[beckmant]

I was watching Wood Works the other day and David made a cove molding for a book shelf using his table saw and a make-shift fence clamped at 45 degrees on the table. The blade was set so that it would only take a 1/16" of an inch at a time. He was running the stock flat on the table across the blade at a 45 degree angle and the shape of the blade is what made the curve in the molding.

Did anyone see this? Is this method of making moldings safe for the saw? Is this how people who don't have a molding maker like Norm make these larger coves?

Thanks for any input.

[Lstrowge]

I saw it and have done it myself. I needed a large (4") Cove molding in Cherry for a bathroom cabinet and the method fit the bill. Did a little trial and error for setup but it worked like a charm. The key is take a little at a time and consistent pressure on the sides and from the top. A bit of warning though, it took ALOT of sanding to get the blade marks out (My blade is a 40t WWII). I don't have a contoured scraper and wish I had. I'll post pics as soon as I get the shot I took from a friends camera. BTW it came out awesome, my favorite part of the project.

[LarryG]

Yes, that's a very common technique (although I've never done it myself) that you'll find described in many woodworking books, especially those dealing with table saw tips and tricks.

Marks used only a single board for a fence/guide. I've usually seen it demonstrated with a board on both sides of the workpiece.

[Mainemarc]

I've read about this technique in several magazine articles; they all say it's safe so long as your saw has adequate power, you use push blocks and you only take very small cuts at a time.

I've also heard that some people first hog off the bulk of the waste material by making regular rips of varying blade heights that follow the approximate contour of the cove profile. And everyone agrees cove cutting with a table saw requires lots of sanding afterwards.

One of the articles I read had a really neat tip to tackle the sanding dilemna though. After you've cut out your coves, set the stock down - cove side up - and cover a section with wax paper. Then layer a piece of fresh sand paper over that, abrasive side down. Mix up some bondo (automotive body filler) and spoon a generous amount of that on top of the sand paper, pressing everything down into the cove profile. Finally, take a block of scrap wood, say a 3/4" x 2" x 5" piece and stick that half way into the pile of bondo.

Let the whole affair dry and voila! You have a custom contour sander, complete with a wooden handle, with the exact profile for the cove molding you just cut!

[JR]

quote:Originally posted by Mainemarc


Let the whole affair dry and voila!

Oooo, I like that.

[Tundra_Man]

I've done cove cutting on my BT. Worked fine. I used the two board method and then made sure I had a push block to hold the wood down over the blade, as it has a tendency to want to rise up. As BigLou pointed out, it did take a lot of sanding to clean things up.

Marc: Cool tip on the custom contour sander. I'll have to give that a try some time.

[RayintheUK]

Jim Frye has written an article on cove cutting jigs for the BT3. It's at https://www.sawdustzone.org/articles...for-the-bt3000

Ray.

[ChrisD]

The FWW website has a 'cove angle calculator', specifically designed for this application.

http://www.taunton.com/finewoodworking/pages/nmw030.asp

[MBG]

It's also a somewhat common practice to cut raised panel door contours using this technique.

[gmack5]

If I remember Jim Fryes' article correctly (it's in the "articles" section of this site) you can minimize the sanding somewhat by slowing down the feed rate. [] YMMV
Here's the article:

https://www.sawdustzone.org/articles/jigs-fixtures/824877-cove-cutting-jigs-for-the-bt3000

[guycox]

Don't forget that you can change the shape of the cove by altering the tilt of the blade and the angle of the stock relative to the blade. I have seen windows app that displays the shape of the resultant cove when the bevel angle and the jig angle are altered.. I can't find the app or the link at the moment, maybe one of the other members has their favorites organized a bit better than mine.

[Brian G]

I used the method for making raised panel doors. I followed Frye's direction, except I attached a sheet of 1/2" ply on the table top, slowly raised the blade through the ply, and made my measurements off of the resulting kerf. That made it very easy to get the settings for the guide boards.

You DO want to get a curved cabinet scraper. You'll wish you did, if you don't, and you'll be glad you did if you do.

[AlexK]

You folks truly amaze me. It's like I was in one of my ATM (Amateur Telescope Making) discussion groups. Inovation truly is the mother of neccesity....so to speak.