Pedestal drill

[Boringgeoff]

Hi all,
Those of you who use your pedestal drill as a milling machine or vertical lathe be aware that if the chuck is on a morse taper it can fall out with possible results detrimental to your health.
From time to time, on this forum, I have read "how to do" posts (mis)using a pedestal drill in this manner and have cringed a bit.
Yesterday I was drilling a 19mm hole through a piece of 2mm steel and had the bit spinning a bit faster than I should have. When the drill bit went through the steel it chattered and then the whole lot fell out of the morse taper socket.
My smaller bench drill doesn't use a morse taper to hold the chuck so my advice is to check your machine before you use it in this manner.
Regards,
Geoff.

[Robson Valley]

Drives me nuts when the chuck falls out.

Big holes in thin metal? I use two pieces of wood. One about 18-25mm thick, pine will do, and a block with the biggest, the worst, the ugliest knot I have (saved for exactly this job and no other). Start with a little 2mm or 3mm pilot through the top wood and through the metal.
Run a bolt through the holes to get the wood and metal matched up. Clamp these things to the knot block, pull out the index bolt and clamp the whole business onto the drill press table (aka pedestal drill?). Sheet copper, brass, aluminum no problems. The density and support of the knot and the sandwich keeps the bit from jumping/tearing out.
You can tell where you are when you start to see the dark shavings from the knot.

[Boringgeoff]

Hi Robson,
What I call a pedestal drill is a free standing drill press and according to the label on my smaller one, that sits on the bench, it's a "bench drill press".
I have used your method of clamping a thin piece of steel to be drilled between two pieces of timber in the past,with good results. I was being a bit lazy on this occasion.
I've had this drill for over 20 years and this is the first time that I can remember the chuck falling out of it.
But my point was that if you've got something hanging off the chuck, spinning unsupported and using a rasp, file, chisel etc aka a vertical lathe then thats where the danger lies if the lateral forces cause the morse taper to come adrift.
The person using the drill needs to identify whether the chuck is on a morse taper or not before using it in this manner. I suspect it would only be applicable to a larger model drill.
Regards,
Geoff.

[rat52]

I have stopped using mine as a drum sander because of this problem.

Is there any way of fixing the taper in position as it is very handy to be able to use the drill for other purposes.

[Boringgeoff]

Hi rat52,
I don't know how you would make it a permanent fixture, as the only thing holding it together is the friction between the two faces of the taper. Its not something I've thought about as I only use my drill for drilling.
There could be other issues here, like the undue wear you would eventually cause to the bearings which may have only be designed to cope with lineal force rather than lateral force.
Regards,
Geoff.

[rat52]

I work mostly with timber so sanding was very convenient and I was considering getting a planing attatchment but not with the chuck falling out.

My drill came complete so it was a surprise to me when it fell out.

The bearing should not be a problem as the lateral forces at the chuck are about the same as the belt drives on the top.

[acmegridley]

The secret to driilling sheet metal is to "back off' the lands of the drill, this stops it grabbing,used to use this technique when building with sheet stainless,never had any pull through problems.

[Robson Valley]

Back in a past life, I custom-built fire-control systems for commercial fireworks and F/X stuff for the movies & TV (being a licenced pyro tech). Lots of holes in lots of steel/Al boxes and cases. My method certainly isn't the only one but it worked well for what I needed.

I've had the chuck pull out twice, I think. Both times was a jammed Forstner bit in a deep hole and the shavings piles up above the bit. Making axle bearing blocks of mahogany for a 4m trebuchet with 150kg steel bar in the counterweight.

My bench drill press is no more than a little Delta 8"/20cm. I counted: the first month that I owned it, I drilled 3,000 holes. These days, the only questions I ask myself are
1. Is it metal? Wear the safety glasses.
2. Is it awkward and very precise? Clamp everything down.
3. Do I ever need to be in a hurry? No.
4. Lots of dust (grinding/shaping abalone shell, etc)? Shop vac is on first and off last.

[dakotax3]

Also in a past life, I used to gently tap the chuck home with a block of wood. Right or wrong, I don't know, maybe the metalworkers have an opinion here.

[Robson Valley]

dakotax3
You really Dakota?

I pounded the chuck back up the hole with a piece of wood. Seems to me it was a friction fit in the beginning, I didn't want to bend anything in the repair. Just had to remember not to bury the drill bits in cuttings that they can't flush out on their own. Deep holes (3"/7.5cm) is up-and-down, over and over again. I am not in a hurry.

I built the trebuchet. I can huck a grapefruit over a 3 storey building from 100 m away.
I can put an orange into the side of that same building at 100kph. Too funny. Cell phones and calculators have really poor aerodynamic stability for a satisfying smack!
My partner/girlfriend/hunting buddy claimed that it was "the dumbest thing she had ever seen me build". Three guesses who brags the most about it. I'm too busy with the next project.

[soundman]

The single most important thing with any morse taper attachment is to make sure is is properly seated.

First it is important that both the internal and external surfaces of the taper are clean and smooth.

a light coat of light machine oil..a bare smear.

Then it needs to be pushed up very firmly, and the bigger the taper the firmer it needs to be pushed in.

mostly i bring the table up and place a block of wood under the chuck and lean on the press handles as hard as seems reasonable.

In my wood lathe I seat the tapers by jamming them in for light work or belting with a block of wood for heavier work.

If you don't have to use a wedge and a hammer..and a fair bit of force to get the taper out, the taper is not seated correctly.

I change and share tapered fittings between my lathe and drill press, so I tend not to belt the tapers in hard, unless I am doing something that needs it.

as far as drilling large holes in thin material....the best thing is step drills or cone cuts.

realy we should be avoiding chattering at all costs..it wrecks cutting edges and results in a poor job.

one other option is to regrind your drill either much flatter in angle or much steeper.

Most of the small sheet metal drills have very shallow point angles....this makes them cut a cylindrical hole that guides them before they break thru......larger drill grinding a steep 'V" with a blunt cutting angle will make the drill work more like a cone cut.

If you are having problems with your MT comming out you probaly are not pushing it home hard enough........the MT was intended to run very big drill for very hard work.

cheers