How to cut this mortise without a drill press

[david kramer]

I need to cut a mortise, 0.5" thick by 7" wide into a piece of 8/4 cherry. The mortise needs to be angled around 30 degrees from vertical. I'm trying to figure out how to do it. One way to do it would be with a series of holes via Forstner bit in a drill press, cleaning up with a chisel. But I don't have a drill press ;).

I have a router, but my bits are at most about 2" long and I don't see how I could angle it over like that and get all of the way through. If I use a hand drill I'm sure I'll make a mess. I don't think I can get the holes lined up like I could with a drill press.

Does anyone have any ideas?
Thx
David

[Stephen Edwards]

I bet you could work this out with a longer bit to use with the plunge router and a shop built jig, built to the angle of your mortise, that the router travels on. I've seen solid carbide spiral bits that have an overall length of of 4 inches.

[Rod Sheridan]

David, layout the mortise with whatever method you normally use (Marking gauge/knife etc).

Cut a block of wood with a 30 degree angle on it to use as a gauge.

Get out the mortise chisel and mallet..........Regards, Rod.

[Lee Schierer]

End mills for metal working come in 4" and longer lengths and they work almost as well as router bits. Buy a 1/2" x 4 " end mill. As others suggested, make a jig to tilt your router and keep it aligned witht he cut and use a plunger router to cut the slot. The only chisel work would be to square the ends. Also be sure to use a backer board to prevent tearout. Yoo will need to make several passes to cut all the way through.

[phil harold]

jig it

make a jig for you hand drill sort of like the one in this link
but you will need to support your wood at the proper angle

http://woodgears.ca/horizontal_boring/index.html

or jig some blocks up like Rod posted

[Stephen Edwards]

End mills for metal working come in 4" and longer lengths and they work almost as well as router bits. Buy a 1/2" x 4 " end mill. As others suggested, make a jig to tilt your router and keep it aligned with the cut and use a plunger router to cut the slot. The only chisel work would be to square the ends. Also be sure to use a backer board to prevent tear out. You will need to make several passes to cut all the way through.

Yes, what Lee said! I forgot to mention the several passes and using a backer board to prevent tear out.

Should you decide to go this route I would also suggest that once you have your jig built and the proper bit for your plunge router that you do a test mortise on a piece of scrap stock that's the same thickness as your money stock.

Here's a link to a 4" bit that might work for you:

http://midwestcutting.thomasnet.com/item/ills-solid-carbide-double-edge-compression-routers/solid-carbide-double-edge-compression-routers/cr5001625?&seo=110

This company also has blank end mills that they will custom cut to whatever you want.

You can reach them at:

Midwest Cutting Tools
262-896-0883
Don Abts

This is a good company that serves primarily the metal working industry. But, like Lee said, end mills can work almost as well as router bits.

You can forget trying to reach them via email. I've NEVER had any success with that. But, if you call them you can get good service. They are one of those companies with a big website that for some reason doesn't use it to its fullest potential. A mystery to me.

[Jamie Buxton]

You can get long straight bits from any supplier of router bits. For instance http://www.eagleamerica.com/product/v102-0102/ea_-_straight_bits shows 1/2" diameter bits which are 4 1/8" long ($18) and 5 1/2" long ($30).

[glenn bradley]

David, layout the mortise with whatever method you normally use (Marking gauge/knife etc).

Cut a block of wood with a 30 degree angle on it to use as a gauge.

Get out the mortise chisel and mallet..........Regards, Rod.

I'm with Rod. I generally do through mortises by hand anyway as they require a bit of finesse to get an acceptable fit.

Is the through mortise part of a functional feature? If it is just aesthetic I would be tempted to do a tenon or floating tenon I was comfortable with in the attaching parts and use a false tenon on the 'appearance' side.

[Stephen Edwards]

You can get long straight bits from any supplier of router bits. For instance http://www.eagleamerica.com/product/v102-0102/ea_-_straight_bits shows 1/2" diameter bits which are 4 1/8" long ($18) and 5 1/2" long ($30).


That's good to know. Thanks Jamie for that link!

[Wes Grass]

Rip the sides off, crosscut the center strip at an angle, and glue it back together. And throw in a couple thin strips of walnut or maple for decoration while you're at it.

Or, you might be able to rough this in on the table saw with a bit of fixturing. Clamp it down *real* good and raise the blade into it. It'd take some thinking, good layout, and adjustable stops to match it up from both sides. Still take some chopping to clean out the ends, but a good portion of the sides would be nice and clean.

(on second thought, I just modeled this up and it looks pretty ugly. But if I were desperate ...)

Other options include drilling an undersized hole, welding a bandsaw blade together in place, and sawing it out with the table angled. But of course you'd have to be able to weld the blade together and tip the table that far.

Or 15 minutes on a Bridgeport, plus straightening the head back up, and it'd be done ;-)

[Vince Shriver]

If, per chance, you happen to have a Bosch or Porter Cable trim router, there are tilt bases made for them. There might also exist such an animal for larger/different router motors as well (do a search).

[david kramer]

Long bits, huh! Who knew? I think that will work just fine. Thanks for all of the suggestions folks.

David

[chris beserra]

Plunge rout with a template on one side. Drill a hole all the way through. Then use a flush trim bit w/ a bearing on the bottom from the other side, starting in the hole you just drilled.