How do I make this cutting board curved joint?

[mreza Salav]

sorry, can't see the photos posted (I know, have to renew my membership but can't do right now).
The method I have described is tested and works perfectly. No need for bushing or guide, does not depend on the shape of the curve (as long as it's not too tight so the router can follow it). You just need a 1/2" top bearing bit and that's it! you need a couple of different bearing sizes as well to change.
It gives you perfect fit, guaranteed.

[Michael W. Clark]

Hi Alan,
One thing you might do to improve the fit, is when making the mating template, do a first rough pass cutting all the way through. Then, cut it again but this time secure the rough mating template so you are only removing a small amount along the router bit's path.

Your situation is different than most. Most of the published methods have you make a set of templates first, then use those to make both workpieces. You already had one workpiece that you wanted to match, so you had to use your workpiece to make the first template that was offset the correct amount so it could be used to make the mating template. This was an extra step for you that you may not have to repeat on the next job if you make the templates first.

[Alan Lightstone]

Your situation is different than most. Most of the published methods have you make a set of templates first, then use those to make both workpieces. You already had one workpiece that you wanted to match, so you had to use your workpiece to make the first template that was offset the correct amount so it could be used to make the mating template. This was an extra step for you that you may not have to repeat on the next job if you make the templates first.

No question I headed down the wrong path in the beginning. I didn't realize that the two pieces wouldn't match due to the thickness of the bit changing the radius of the "matching" piece.

I was surprised that making the second piece using a suggested technique didn't provide a great fit. And using Bondo to fill in the gap did make the joint much tighter, and I was able to glue it successfully together yesterday. Ignore the glue stains - I haven't sanded it yet, or cut it to size.

A better / easier technique, as several have suggested above would have been better from the start.

I would love to see some samples to see which of the above techniques really work, and which ... not so much.

Man your routers. On you mark. Get set. Rout...

[Malcolm McLeod]

Interestingly, (or frustratingly) the two templates I made with the 1/2" rabbet bit seem perfectly symmetrical, but have a tiny gap between them. I'm not sure if this will go away with clamping and gluing, or now I'm wondering about that Bondo trick on one of the patterns with the other one taped off. Another reason why this would have been SO much easier with inlay. The plan is for the final thickness of the cutting board to be 1-1/4".

Any thoughts?

Loving the discussion and the debate, BTW. Really shows the strength of the community here.

Don't recall anyone mentioning this so far, and not exactly fitting with your initial proposition, but.... If you wanted an inlay to show on both sides:

1. make the field board at 1-1/2" thick initially,
2. route the (curved?) inlay dado at 1-3/8" deep,
3. add glue & fill dado with your contrasting wood of choice (leave it a little proud),
4. plane infilled 'front' flat,
5. then plane the 'back' down to final 1-1/4" thickness, and so expose the inlay..??

In theory, you could repeat steps 1-4 several times, then step 5 as final - exposing all the infill on back side. I recall the FWW article on similar method, but don't have it in front of me. Seems like the first 4 steps match their method. I just can't remember if they proposed step 5?

[Alan Lightstone]

Don't recall anyone mentioning this so far, and not exactly fitting with your initial proposition, but.... If you wanted an inlay to show on both sides:

1. make the field board at 1-1/2" thick initially,
2. route the (curved?) inlay dado at 1-3/8" deep,
3. add glue & fill dado with your contrasting wood of choice (leave it a little proud),
4. plane infilled 'front' flat,
5. then plane the 'back' down to final 1-1/4" thickness, and so expose the inlay..??

In theory, you could repeat steps 1-4 several times, then step 5 as final - exposing all the infill on back side. I recall the FWW article on similar method, but don't have it in front of me. Seems like the first 4 steps match their method. I just can't remember if they proposed step 5?

I just looked at the Article (FWW, May/June 2013 - "A Unique Cutting Board").

They did not propose step 5. Interesting method, Malcolm.

[Mark Hennebury]

Got a video done, let me know if its okay. If you have any questions or suggestions, i would very much appreciate hearing them.
I took some overhead shots also, and may insert some of those later.

[Mark Hennebury]

Hi Alan,

You could have used your one good piece to make a template and used the single template method that i showed to trim the bad fitting piece. There are lots of different ways to do this stuff, It's all good to see a few different ways, food for thought for the future.

No question I headed down the wrong path in the beginning. I didn't realize that the two pieces wouldn't match due to the thickness of the bit changing the radius of the "matching" piece.

I was surprised that making the second piece using a suggested technique didn't provide a great fit. And using Bondo to fill in the gap did make the joint much tighter, and I was able to glue it successfully together yesterday. Ignore the glue stains - I haven't sanded it yet, or cut it to size.

A better / easier technique, as several have suggested above would have been better from the start.

I would love to see some samples to see which of the above techniques really work, and which ... not so much.

Man your routers. On you mark. Get set. Rout...

[Mark Hennebury]

Here is the video from overhead if you want to see things a bit closer up.

If anyone can sit through both, your opinion would be much appreciated.
I am hoping to do some more demonstration videos, I have a lot to learn and appreciate any help, advice or constructive criticism in that regard.

[ChrisA Edwards]

Thank you, I found that video helpful.

For those that do not have the ability to make their own bushings, I believe this kit, from Whiteside, https://www.amazon.com/gp/product/B0...WTFI0BL8&psc=1 would achieve the desired results.

My only suggestion, not that this video really needed it, for the cut, I would have zoomed the camera down more on the actual cut.

[Mark Hennebury]

Hi Chris,
Thanks for the reply,
I will work on this video to make it shorter , cleaner and better, I will see if I can add some cad drawings etc.

Thanks, Mark

Thank you, I found that video helpful.

For those that do not have the ability to make their own bushings, I believe this kit, from Whiteside, https://www.amazon.com/gp/product/B0...WTFI0BL8&psc=1 would achieve the desired results.

My only suggestion, not that this video really needed it, for the cut, I would have zoomed the camera down more on the actual cut.

[Alan Lightstone]

Thanks for the video, Mark.

What I see as the most difficult step (and the one I had some issues with) is making the second template and making sure that the router doesn't deviate at all from the pattern. If it does, you decrease the size of the template as it routs into that, and that piece gets thrown out. It's certainly easier, and more forgiving to rout away waste and have the template you are making protected, like routing the first piece. I found it took a decent amount of force to keep the router hugging the pattern, and you can't let up as you go around the curve. I must have a little bit around the line as I made my second pattern as I had a small gap. And I fixed that with the Bondo and clamps.

[Mark Hennebury]

Hi Alan,

On the single template method that i have shown.

Trim the righthand part to rough size on the bandsaw, leave a small amount 1/16" to trim with the router. then climb cut the part on the template, it will push the router tight to the template. If you do standard upcut on the righthand part the router will tend to pull away from the template and into the cut. And you will have to fight it to keep it tight to the template. Climbcut it and you wont have that problem.

Thanks for the video, Mark.

What I see as the most difficult step (and the one I had some issues with) is making the second template and making sure that the router doesn't deviate at all from the pattern. If it does, you decrease the size of the template as it routs into that, and that piece gets thrown out. It's certainly easier, and more forgiving to rout away waste and have the template you are making protected, like routing the first piece. I found it took a decent amount of force to keep the router hugging the pattern, and you can't let up as you go around the curve. I must have a little bit around the line as I made my second pattern as I had a small gap. And I fixed that with the Bondo and clamps.

[Edwin Santos]

This has been an interesting technique thread. I'd like to contribute another alternative, neither better nor worse than the others but just another option.

Some years ago I was impressed with an approach to cutting perfectly mated curves that was showcased in a FWW article. The article "Cut Matching Curves" appears in Issue #179.

What the author did was cut a single template edged with a flexible 1/4" MDF strip secured with glue blocks. Then she made a perfectly mated template by clamping a second MDF strip to the first which conformed to the first curve and while clamped, she then secured this second strip to a mating template using glue blocks. Ultimately the final workpieces are rough cut at the bandsaw and then final cut with bottom a mounted bearing guided flush trim bit using the templates.

It's a little difficult to explain, but here is a link: https://www.finewoodworking.com/2005...atching-curves.

This is yet another option for cutting perfectly mated curves.

[Alan Lightstone]

Wow, her technique is a lot more work than anyone here has suggested. It looks like it should work, but our crew here has better suggestions.

[Mark Hennebury]

Here is a video of a guy making cutting boards with complimentary curves straight off the bandsaw.