Roundover a 45 miter joint

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Forum topic by DavidI posted 10-22-2018 01:29 AM 1834 views 0 times favorited 8 replies Add to Favorites Watch
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8 posts in 2129 days

10-22-2018 01:29 AM

Topic tags/keywords: question

Building a small box for a cremation urn. I’ve joined the sides with 45 degree miters. I’d like to soften the outer edges with a round-over routing. If it were just a butt joint, I’d be routing a single piece of wood. I believe, though, the fact that the edges are glued together will provide enough support and negate the fact that the edges of each piece are really thin pieces (hope that makes sense). So in short, does anyone see any problem with doing a round over on an edge that is to pieces glued on 45 miter?

8 replies so far

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John Smith

2440 posts in 938 days

#1 posted 10-22-2018 01:37 AM

depending what is “really thin”, I would start with a sanding block,
then to the foam flexible sanding block before a power tool.
or even a small block plane if you have one.


-- there is no educational alternative to having a front row seat in the School of Hard Knocks. --

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2859 posts in 1675 days

#2 posted 10-22-2018 01:47 AM

You didn’t mention the type of wood. Some species are more prone to splintering at the point.
(on what you call the thin section, I call the point)

A sharp router bit and you should be fine.
If you notice any splintering you can go the other direction and do a climb cut.
You should be fine using a router.

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5790 posts in 3127 days

#3 posted 10-22-2018 01:58 AM

Normally I would say go for it, but the “really thin” part makes me hesitate. Two things to consider are the radius of the bit and how thin is “really thin”. You will be removing material so it will be possible to remove so much that there is nothing left to hold it together. Caution, here.

-- Bondo Gaposis

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8 posts in 2129 days

#4 posted 10-22-2018 01:58 AM

Wood is canary. I attached some pics. By “thin”, just meant that the edge of each piece of wood gets thin because of the 45. But it’s now glued, so one mass that I’m running a round over on. Basically looking to round over all outside edges (after I finish the lid, of course). Btw, I’d be using a 5/16” radius bit. Brand new Freud Quadra Cut. walls are 1/2” thick.

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5790 posts in 3127 days

#5 posted 10-22-2018 02:32 AM

I think it will be fine. You can easily tell by setting a compass to 5/16” and setting the point on the glue line and swinging an arc. You will see how much material will be removed.

-- Bondo Gaposis

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8 posts in 2129 days

#6 posted 10-22-2018 02:35 AM

I think that part is ok. I’ll measure to be 100%. In the end, it’s probably a stupid question. Was just thinking if I was risking anything unusual in the area of tearing and such by rounding the outer edge of mitered joints like this.

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8909 posts in 3352 days

#7 posted 10-22-2018 02:59 AM

Not a stupid question at all.

I would use a backer board on each end to prevent tear out.

Practice on scrap if you have some.

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2762 posts in 1379 days

#8 posted 10-22-2018 03:02 AM

It’s almost done and it looks perfect. I’d keep power tools at least ten feet away from it at all times.

-- Andy - Seattle USA

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