Precision-drilling wood edge

[Mike Rocket J. Squirrel Elliot]

Crossposted alt.home.repair / rec.woodworking -- mainly because this is sort of a woodworking question, but the wood is part of my bathroom wall.

I have received a pair of barrel hinges from Rockler. I'm going to try to use them to hang the new medicine cabinet door on the cabinet I built into the wall. An earlier post described how the door fits flush against the face of the cabinet, and barrel hinges seem to be a good solution. So anyway.

I need to drill a 14mm diameter hole into the edge of the cabinet side to accept the hinges. The side is 3/4'' MDF. 14mm is 0.551'', which does not leave a lot of sidewall in 3/4'' material -- about 3/32'' per side. If the cabinet was NOT in the wall I would put the sides into my drill press so I'd have a fighting chance of getting the hole straight. But it is in the plaster wall and trying to do this job by eye and with a hand drill is not likely to succeed. (This is what happens when I don't plan ahead real well.)

What kind of hand drill-alignment gadgets are there that can help a fellow drill square, straight, and level?

If I can run a 14mm diameter, 15.5mm deep hole exactly down the middle of this 3/4'' -- TWICE! -- I will be a hero in my own home. My wife will think I am quite the he-man, my kids . . . well, they are teenagers. I might be able to raise a "whatever," out of them. But I'd be darn pleased.

[Chris Carruth]

You can make a drill guide out of 1" thick stock, with the holes made on the drill press. Use the hinge itself as a pattern to mark the holes. Once drilled, use doublesided tape to secure to the side walls and drill as needed. Remove and mount hinges.

[Mike Rocket J. Squirrel Elliot]

Hm. Lemme think about this. With a barrel hinge, there is ONE hole per hinge. In my case, the hole is 14mm diameter, and goes in 15.5mm deep. Right into the edge of the 3/4'' MDF cabinet wall.

Knowing me, if I taped a pre-drilled bit of stock against the wall, I'd probably tug the tape out of place when I shoved that 14mm brad-point drill down into it. But I could make a right-angled fixture and screw it onto the side of the MDF -- I could patch the screw holes later and paint over them.

I think you have answered my plea for help! Thank you!

-- Mike "Rocket J Squirrel" Elliott

71 Type 2: the Wonderbus 84 Westphalia: "Mellow Yellow (The Electrical Banana)" KG6RCR

[MG]

Could use a router with a 1"/4 or 1"/2 bit, whatever your router collet is, and plunge placing the router face against the wall. Once you got a pilot hole you have a chance. Whatever! MG

[Mike Rocket J. Squirrel Elliot]

Heh. Not a bad idea . . . except I reckon the 14mm brad-point bit I have on order is too long. I like it otherwise, esp. the idea of jamming a

14mm bit into MDF at 20,000 rpm. Yee haw!

[d.kessell]

Rocket J. notes: Turtles have a drag coefficient of .03 Can you imagine how slow they'd be with more drag?

Dan

[Morris Dovey]

Or you could use a C-Clamp to hold your right-angled fixture in place and not have screw holes to patch...

[Paul Kierstead]

Err, he never said put your 14mm bit in the router. Read.

[Mike Rocket J. Squirrel Elliot]

Turtles IN drag?

[Mike Rocket J. Squirrel Elliot]

Oh, right. I jumped to a conclusion. Use the router for the pilot hole. My bad.

[MG]

NO,NO The routher is to drill only a pilot hole. Then you can have a better feeling when you drill free hand. Perhaps you want to go with small increment in diameter. The router leaves you no choice on the bit diameter.

MG

[Mike Rocket J. Squirrel Elliot]

Um. Duh?

[Mike Rocket J. Squirrel Elliot]

Okay, now back to this excellent suggestion which I initially misunderstood.

To recap: I'll be mounting two 14mm barrel hinges into the edge of 3/4'' MDF. The body of the barrel hinge measures 0.558''. The mfgr specifies

14mm holes (0.5512) so this is a press-fit. A 35/64'' holes will be too tight, and the mfgr does not recommend oversized holes, so 9/16'' will be too loose, so 14mm it is. The hole is to be 15.5mm (.61'') deep.

I did a couple trial plunges with a 1/4'' straight router bit to get a pilot hole then followed that my largest twist-drill bit (1/2'') and it tore the sidewall, so a twist-drill bit is not the way to go. I have a

14mm brad-point bit coming from Lee Valley, but I reckon it will tear out the thin side wall, also.

I don't have a 14mm straight router bit, but a test-drive using a 3/4'' diameter bit real close to the edge did not result in sidewall tear-out.

I reckon I could do the whole job with a single plunge if I had a 14mm diameter straight router bit w/ 1/4'' shaft. Rockler doesn't seem to have this listed. Does such an animal exist?

[Joe Bobst]

1/2 " holesaw, maybe?

Joe

[MG]

Hole saw, is a possibility, A Forstner bit (spelling?) is another possibility, but as the hole saw can not be enlarged. Finding a 14mm Forstner bit may be difficult but they cut a very clean hole with a flat bottom and once centered they stay put without drifting unless you want to.

A Forstner bit does not like a pilot hole, just a smal dimple to locate the small tip.

On the other hand you may want to sacrifice a cheap 9/16 router bit by grinding it down to 14mm, only a couple of lics on the grinder. You may even go a little conical.

Now for the suggestion you do not want to hear. There is always epoxy glue to fill up the gaps. This is a challeging job, hope it goes well.

MG

[Duane Bozarth]

Go back to the template idea...make one from either hardwood or a piece of angle if you have it (since you said you have a drill press, this should be easy). Go with a twist or Forstner bit (although if you make a pilot hole first, a twist drill bit should be ok). To minimize/eliminate the tearout, clamp a piece of hardwood or flat iron on each side...

Whether there is a 14 mm router bit I don't know, I've not researched metric sizes, but if it is actually a 14 mm hole required by the hinge, there has to be a corresponding tool...

I've used a lot of Soss hinges over the years, but at least when I was using them they were English measurements...

[Mike Rocket J. Squirrel Elliot]

I have only access to the side /inside/ the medicine cabinet. The other side is buried behind the plaster wall.

Well, I've a 14mm brad point bit coming from Lee Valley, but I expect it will tear out like a twist drill.

This barrel hinge comes from Rockler, I presume it is euro or Asian-sourced.

[Duane Bozarth]

"Mike Rocket J. Squirrel Elliott" wrote: ...

...

All I can say is "plan ahead"... :( Drill pilot and go slow...after drilling if needed you can epoxy over any loose area on the inside and let cure. If similar to Soss, depending on the size, you may just epoxy it in place.

[CR]

Asian-sourced.

Maybe a 14mm end mill used for metal work in a horizontal or vertical milling machine? I have used them before in a router and drill press. They leave a flat bottom and have no trouble chewing a clean hole in wood or MDF.

CR

[John Hines]

You will be pleasantly surprised. A brad point bit has cutting spikes at the edges, so it makes a clean cut in wood.

The drawback is they (bradpoints) are only good in wood, or wood like materials. They don't cut metal.