Drill bits with a Router -- is it possible?

[Carlos Moreno]

I'm working on something that requires a hole at an exact position and *perfectly perpendicular* to the wood's surface.

This would normally require a press drill. Except I don't have a press drill. My arsenal of power tools is limited to a regular drill, a circular saw, and a router (with plunge base + fixed base).

So, I'm thinking I could use the router in its plunge base to "simulate" a press drill. The problem is, I have to open a hole in a piece of wood which is 3 inches deep. I have no router bits that long.

Is there a way to adapt drill bits (for which the shank is slightly below 3/8 -- but a lot more than 1/4) to the router? I think I could easily accomplish the task if I could do that.

If it's definitely not possible, can you think of some other trick that could do it in this case? (I don't want to rush my decision to get a press drill -- when I get it, I want to have time enough to shop around and take a good decision without any hurry)

Thanks for any advice!

Carlos

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[David]

Seems like you are someone looking for an accident. There are enough problems with router bits coming out of collets without inviting trouble by "adapting" a drill bit for router use ("mis-use" is more appropriate). Is the drill bit rated to turn at the high speed developed by your router? Are you fully insured (medical and life)?

A Delta Drill Press is more than adequate for most home usage, and won't break the bank. Model 17-965 is a good one.

David

Carlos Moreno wrote:

[Edwin Pawlowski]

I'm scared just thinking about that drill in an adapter spinning at 22,000 rpm.

If you don't want to buy a drill press yet, ask around if you can use one for a short time. How about the maintenance department at work? Or a neighbor that you always see fixing stuff? Or a friend that is a machinist?

[Steve]

--Unless you're serious about your Darwin Award candidacy, pop for the $25 for a holder/adapter to put your hand-held power drill in so it'll become a pretend drill press. Look at Harbor Freight, ACE or even The Borg. Those devices often prove handy to have about long after you finally buy a real operational drill press.

[J. Clarke]

Do not, repeat _not_ try to use a drill bit in a router.

What you could try is plunging as deep as you can with the router then use that hole to guide a regular drill bit of the same diameter used with your regular drill. If you need a larger hole you can then use the one you just drilled as a pilot hole.

Better solution, as someone else pointed out, is to just get one of the inexpensive gadgets that you clamp your regular drill into to hold it perpendicular to the work.

[Phisherman]

[gandalf]

------------------- Personally I think it would be plain dangerous to attempt what you suggest.

A couple of people have suggested you get a portable drill stand. I agree with them. I have one of these:

(if the wrapping screws the link up, it's a WolfCraft toy. And very handy too)

Downside of these devices, or at any rate this one. Is that while they're portable the drills they are designed to accept are not.

[Carlos Moreno]

Thanks John, and thanks to all that replied!

No, don't think my IQ is that low :-)

A follow-up question, at the risk of sounding dense/dumb... It's just that now I'm a bit curious about it.

From the answers I got, I kind of sense that the two main problems are the speed (drill bits are not made to go at such high speeds as router bits), and the fact that fixing the bit to the router head, when it doesn't fit naturally, is asking for trouble.

My (follow-up) question is: if I set my router at lowest speed (which I believe is 8000rpm; it's a Bosch 1617EVSPK)

*AND* the drill bit has a 1/4 shank that fits perfectly in the router head, is it ok in that case? Or is 8000 rpm still too much for the drill bit?

Any other aspects in which I would be asking for trouble?

I clarify that I very clearly understand the notion of "DO NOT attempt this" and that I will NOT be attempting any of these tricks without having LOTS of evidence that it should be safe enough (a bunch of replies from the experts out there telling me that under such and such conditions is safe would be considered enough evidence :-))

Once again, thanks all for your advice and your concern!! I promise I'll be a good boy and behave myself and keep safety in mind! (FWIW, I'm the kind of person that doesn't carry *any* solid object in my car without restraining it with the seatbelt... What I'm trying to say is that trust me, you're preaching to the choir with your emphatic advice regarding safety issues :-))

Cheers,

Carlos

[Silvan]

I can't remember how fast my DP goes. A quick little online survey seems to indicate 2500 RPM as a top speed is pretty standard, with a few going up to

3,000.

That's the maximum speed, and any speed/size chart will tell you that you don't want to be spinning anything big at that speed. I don't have the chart committed to memory, but I'd say the high end of my DP (drill press) is only good for bits that are very much on the small side.

Spinning anything with a 1/4" shank at 3,000 RPM is probably not recommended (won't swear to that absolutely; maybe in soft wood you could get away with that) and you're talking about going almost double that. What do you think?

Sounds pretty stupid to me.

Best way to drill such a hole without a drill press, and without one of those guide things, is the hardwood block someone already suggested. It's not absolutely *perfect*, but if you only need a couple of holes, and if you use a pretty thick piece of a good, hard wood, it works. That's how I drilled the holes in my workbench. With a Forstner in a portable drill, with no extra guide flummy. They're not perfect, but I wasn't trying that hard for perfection.

If you can't find any other way to get a block of wood with a suitable hole, maybe someone here can help you out. Where do you live? I have a vague idea (because of your name, and because you said "press drill" instead of "drill press") you might not live in one of the "usual" places, (US, Canada, UK), so it might be a bit tricky mailing you some guide blocks, depending on how hostile your country's government is toward ours. (I've been there a time or two. Customs and agricultural protection laws can be a PITA.) (No offense if you live in Wisconsin or something.)

[Pixmaker]

Sort of. . . I think. But it would be a kluge and only worth it for one or two holes...not a whole buncha them.

First, find a drill bit that's the right size but with a ¼ - inch shank. Chuck it in your router (with the power cord unplugged.)

Keeping the power cord unplugged, turn the bit, by hand, using the router to obtain the absolute vertical alignment you need.

Another ploy would be to find a friend or a shop with a drill press. Have them drill a clean hole through a block of hardwood (oak or hard maple) and then use it as a drill guide.

Others may have better ideas.

Pixmaker in FLL ========================== It's not the heat, it's the humidity! ========================== (...Think the humidity's bad? You should watch us vote!)

[Steve Dunbar]

That depends on the size of the drill bit. The larger the diameter of the bit, the slower the speed that should be used.

New York Twist Drill recommends a speed of 300-400 feet per minute for drilling wood (200 fpm if using a carbide bit). 8000 rpm works out to 524 fpm for a 1/4" drill bit, so your speed is a bit high.

To convert between fpm and rpm:

N = 12 * V / (pi * D)

where N = spindle speed in rpm, V = cutting speed in fpm, and D is the drill bit diameter in inches.

[Prometheus]

I don't know, but I do most of my drilling at 620 rpm. That's the lowest setting my my drill press, but even the highest setting is still considerably less than 1/2 the 8000 rpm speed. At the very least, you are going to destroy the bits if you try this with hardwood or metal, and it's fairly likely that the bit might splinter into shrapnel and kill you. You might 'get away' with it once or twice using it on something very, very soft, but you're asking for a lot of trouble even then, IMO.

Another thing to consider is that an average drill bit is going to be sticking out further than your plunge router base, so you're not really gaining much of an advantage that I can see. Why not just get the drill jig, or a couple of machinist squares to line up the bit?

[Robert Galloway]

I've used a 1/8 bit in a Moto tool in a pinch. 30,000 rpm. Use some judgment as to whether the bit runs true and regarding the speed your turning and feed rate so as to avoid overheating and ruining the bit. A lot of things work in a pinch if you're careful and pay attention to the signals you get back from your tools.

bob g.

Steve Dunbar wrote:

[patriarch]

"Edwin Pawlowski" wrote in news:wLAcd.18306$ [e-mail]:

Lowe's had a benchtop Delta for $99 yesterday. That's cheaper than the co- pay at the emergency room.

Drill press - about 400 rpm Router - about 22000 rpm

[LP]

Try the tool at this link. It should do what you want, but you may have to go to McMaster-Carr or someplace like that and get an extended length bit to make it work.

the link wont work, just google for craftsman drill guide 67173

LP

Sun, 17 Oct 2004 16:33:52 -0400, Carlos Moreno wrote:

[Andy Dingley]

Far too high.

I wouldn't drill 1/4" in timber at over 1000 rpm (from choice). You can _drill_ faster than this (although not 8000 !) but your risk is of snatching if the drill decides to stick or jam. At this speed there'll be a risk of over-heating which will accelerate the jamming problem.

Like many people, I have a cheap square-chisel morticer that can be used as a drill press. This is a direct drive motor at 1400 rpm (1700 in the US) and is certainly unpleasantly over-speed for drilling above

1/8".

If you do try this, you'll drill a pefect and highly polished hole. Until you're almost finished when there _will_ be a bang and the router will fly sideways, leaving some parts of the drill embedded in either your or the timber.

[Carlos Moreno]

Thanks again to all that replied, including my follow-up question.

The conclusion seems definitive -- far too high speed to take any risk.

I had thought about starting the hole with the router (going just 1 inch, which is the depth of the straight bit I have) and use that as a guide.

Some of you suggested using a block of hard wood as a guide -- problem is, the pieces I need to hole in are Mahogany (*very* hard -- I found the Honduran one, and it is extremely heavy and rock solid). What I'm thinking is that I could start the hole in it with the router, and then take two extra little pieces, open holes in those, and glue them together, such that now I'll have a pretty long guide. I guess that should increase the precision.

BTW, the main reason why I'm not going for a drill press at this point is that I have no room for it (I improvised a small workshop in a pretty tiny room :-( )

Anyway, I'm very grateful for all the advice and the time you have taken to offer guidance!

Cheers,

Carlos

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[John Barry]

"perfectly"? Won't happen. But, you can get really close by making an alignment tool with a guide bushing. Industrial hardware stores carry all sorts of these bushings. Once you have the bushing in hand, you drill/bore a hole to match its o.d. in a bar of aluminum, or, say, oak, and force the bushing in until its flange sits against what will be the top face. Clamp that assembly in place on the work piece, insert drill ...

Might be the least expensive way out. Perfect? No. Safe? Definitely- used all the time in Kreg jigs.

John

[Carlos Moreno]

No, I'm actually in Canada (Montreal). But your guess is still good, in that English is not my native language (I've been in Canada for 12 years).

I always tend to get names wrong -- I have certainly heard and seen in the stores the right term ("drill press"), but for some reason, my dyslexic brain swapped the words :-))

Coming back to your offer -- I think I should be able to assemble my own block with a perfectly perpendicular hole (as deep as needed), by using the router on pieces (1 inch thick) and then gluing as many pieces as necessary (I can always use a metallic piece, or the drill bit itself, to keep the wood pieces aligned and keep the perfect hole).

If this is too much trouble, I guess I'll come back and give you a shout! :-)

Thanks,

Carlos

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[Tim Douglass]

I would suspect that there will be too much flex in the bit and it will begin to whip then break apart at that speed. I seriously doubt that any normal drill bit should be trusted beyond 3-4000 RPM.

Tim Douglass