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I'd like to add a 22.5 degree chamfer to thick (1.5"+) material. In the past I've done small chamfers on a router table with a chamfer bit. Unfortunately I can't seem to find any chamfer bits that are big enough to cut 1.5". What's a good way to go about this. I suppose it doesn't have to be exactly 22.5 degrees (for aesthetic purposes only), but I do want it repeatable and uniform (e.g. 20 degrees along the entire edge is fine). Is there a way to use a shorter router bit that I'm not seeing? Are there other tools for the job? Should I start with a short chamfer and start planing the material down?

Edit:

The work piece is a 1.5" tall cylinder with outer diameter of 10" and inner diameter of 6" (e.g. 2" wall thickness). I'd like to chamfer both the inside and outside edges.

Edit2:

I decided to "cheat". A friend has a CNC router so I just ran it on that. Took forever and had a few gcode errors, but came out well enough.

  • Table saw with blade buried in sacrificial fence? – keshlam Jul 27 '15 at 6:34
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    Would you please add a picture? – rob Jul 27 '15 at 16:47
  • CNC can be a touchy subject. I don't consider it cheating though, just another tool. Over the years, some woodworkers have chosen to shun power tools and some embrace them. I view CNC as a similar evolution of the craft which provides options previously not available. Then again, I'm studying computer engineering, so I might be biased ;) – Daniel B. Jul 31 '15 at 14:19
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    @DanielB. yeah...I think it would have been "cooler" if I could have done it by hand, but there is enough complexity in this project to make up for it elsewhere. I'm an electrical engineer and it seemed a little silly to shun a tool I'm very familiar with from work just for the sake of shunning it. – Doov Jul 31 '15 at 23:01
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Planing by hand would be the standard response for any hand-tool aficionado, as this is how chamfers were done before power tools came along. This can be done freehand, by planing to marked or gauged lines on the face and edges, but it's easier to use some kind of chamfering jig if accuracy and repeatability are desired.

Because I'm presuming you'll want to do four sides of something you're going to need to go cross-grain and planing a significant length and width of end grain by hand can be a bear, even if you have the right type of plane. So at least for those ends I'd suggest you use some kind of power tool to remove all or most of the material, then clean up taking very light passes with a block plane, with a card scraper, or just by sanding.

My thoughts on suitable power tools were in rough order: table saw, bandsaw and belt sander.

With the table saw the blade can obviously be tilted to 22.5° and then it's just a straightforward saw cut.

With the bandsaw, if the bed can't be tilted to the required angle then an angled bed can be built from plywood or MDF. But obviously if you're doing the chamfers on the edges of a large workpiece manoeuvring it safely could be impossible.

The belt sander I thought could be used in one of two ways: either freehanding it (just to hog off most of the material) or by setting the sander upside down, tilted to the correct angle and then the workpiece could be slid past it, face side down, almost like you were using a jointer. If a sliding jig is rigged up and the sander fixed firmly in place I think this could give very accurate results.

  • The table saw, assuming you have one, seems like the simplest and safest method. – FreeMan Jul 27 '15 at 12:32
  • Thanks for the suggestions! I should add some detail as to the actual work piece here. Trying to chamfer a 1.5" thick circular piece with a circular cut out from the inside. I'd like to chamfer both the outside and inside edge of the resulting 1.5" tall cylinder. I suppose I could use the table saw and several passes to try and get the outside edge and then finish with sanding, but the inside edge is tricker. – Doov Jul 27 '15 at 16:18
  • @Doov, yes the details of your piece would have been very useful! I don't think any of the techniques could reasonably be applied to the inside edge (including hand planing, unless you have a compass plane). After cutting roughly to shape e.g. with a jigsaw, the outside circumference, could be dealt with by running past the belt sander much as with flat pieces. But for the inside there are only two ways that occur to me: using the rounded toe of the belt sander, held freehand, or with a suitable spokeshave. – Graphus Jul 28 '15 at 7:36
  • Note that some jigsaws can be tilted. The question would be how stable that is, how well you can stay on the circle, and how much hand-work would be needed to fair the curve and smooth the surface. – keshlam Jul 30 '15 at 18:28
  • @keshlam, yes I realise jigsaws can be tilted (and even if this is beyond the built-in tilt something could be rigged up). But I wasn't sure about the cutting depth given the tilt. Stability & evenness of cut could be sorted by attachment to a circle-cutting jig, which if necessary could incorporate a wedge to get the correct angle. – Graphus Jul 31 '15 at 7:08
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For something that big, I would use a table saw to make the main cut, and then use a belt/orbit sander to smooth it out nice. If you are good with a hand plane then you might leave a little to be planed off with a hand plane.

That much is a lot and using a bigger tool is the better way to go.

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Based on your edit and comments, it sounds like you want to chamfer the inside and outside circumferences of a short but large diameter hollow cylinder so each end of the cylinder comes to a point, so you end up with a toroid with a rhombus/diamond-shaped cross-section. In that case, I think a lathe would do a great job.

Another option would be to use a trim router with an angled base, spiral bit, and template and/or jig.

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Given your further description:

Trying to chamfer a 1.5" thick circular piece with a circular cut out from the inside. I'd like to chamfer both the outside and inside edge of the resulting 1.5" tall cylinder.

I'd suggest getting a milling bit - such as it used for metal or wood CNC machines - and chuck it into your table router at an angle.

You'll have to develop a jig for the part you're chamfering to obtain a very round result. Clamping it to a board with a nail hole in the center, and rotating it around that center while routing seems the easiest.

If your router doesn't tilt add a wedge below it and incorporate that into your jig. Alternately, use a hand router and a wedge, attached to a length of board with a nail at the center of the project part. Then move the router around the part.

You can also use a jigsaw in a similar manner without buying the milling bit, but the blade might wander. Doing this with a table saw is possible, but seems a bit more risky than a router.

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Another idea would be to use a shaper. A shaper is very similar to a router table except that it is meant for bigger cuts. You can buy a chamfer cutter that would handle you 22.5 degree cut for 1.5 inch thick stock. A quick search turned up this result: Chamfer Shaper Cutter

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