Hand Drills, Drill Presses and Drill Bits for Model Building

Drilling is a fairly complex task depending on many factors as well as the quality you want to achieve.  It becomes simpler when there is a large margin for error and you don't care about the quality of the finished the hole.  If that's the case then there's not a lot to say.  Just drill the hole.

For the rest of us who want very accurate and clean holes there is a lot to consider.  Because drilling is a task we do a lot of it's worth investing in the proper tools.  I built models for a couple of decades wanting a drill press and never acquiring one.  If I could go back I would have purchased this tool much earlier on.

When it comes to transportation I would like several vehicles:  A motorcycle for nice days when I don't have to carry anything, a sedan for times I don't need to transport anything except a few people with their lattes and quarterly reports, a van to transport models and a full size pickup to transport lumber.  I didn't include a limo because I prefer to arrive at red-carpet events in my Augusta Helicopter or my civilian Apache.  While that would all be very expensive it would be the most efficient way to get around if you don't consider anything except the transportation part while ignoring the costs and hassles of ownership.

A lot of tools are like that.  When it comes to drilling I think the following would be ideal: A floor drill press, a small precision model-builder's bench drill press, a heavy-duty 1/2" corded drill, a very light small cordless drill and several pin vises.

As I see it, if you want to build a shop, work around the house and build accurate models — particularly scale models then you will be investing about $700.00 in the various drills including one high precision replacement chuck but not counting any other accessories or the bits themselves.  For the guy who builds models and does very little shop-building or home maintenance then you will probably get by for a long time with just the small cordless drill.

You should seriously consider investing in a decent drill press.  We drill as many holes as anyone.  If it's just going to be used for models then a good model-builder's drill press is probably a better choice than a standard bench or floor press because the chucks can take bits at least as small as 1/32" and an inexpensive adapter will let you use very small numbered bits.  Now you're investing about $250.00 to $300.00 for the electric hand drill and drill press.  Even a small cordless drill will drill the holes needed to build a workbench unless you're building a classic, solid hardwood bench having large or deep holes.

This is a long page so here are links to various segments:

• Drilling Rules and Tips (really unnecessary because it's the very next thing)
• Manual Drills
• Electric Hand Drills
• Drill Presses
• Drill Bits

I'm not including other kinds of drills such as pneumatic drills because I've never used them, know nothing about them and if they were useful for model-building I'd probably know something about them or at least heard of them.

Drilling Rules and Tips

Safety

This is where I give you the standard lecture about being safe.  If you ever saw "City of the Living Dead" then you know that a horizontal boring machine can easily drill into your skull, through your brain and out the other side of your skull.  And the sadist father of the girl you were groping earlier who does the drilling laughs the whole while.  He may think it's funny now but he won't think it's so funny when his expensive drill bit becomes rusted and useless due to being covered with wet brain matter.  But that's his problem.

For your personal safety you should avoid being around drilling machines and hanging out with your sadist friends at the same time.  Also, don't use a corded drill when you're taking a bath.

Drills can hurt you badly.  I've stuck a finger into a spinning drill in my drill press on more than one occasion and the results weren't pretty.  Loose clothing is a really bad idea.  Please, please, please, please take this stuff seriously.  A drill doesn't have to be big and powerful to hurt you.  Most drill presses have a belt drive and can have a lot of torque which means the bit grabbing your shirt sleeve or tie, pulling you into the tool, probably breaking some part of your hand and arm, cutting you deeply and your face being tightly against the drill press plus you being freaked out and unable to hit the off switch as quickly as needed.

Drilling Speed

Craftsmanship Rule #1:

If you are unfamiliar with the material you are drilling OR you are unfamiliar with the drill bit OR you are familiar with both the drill bit and the material but unfamiliar using that bit in that material then test drill some scraps of the same material to figure out the best drill speed and possibly try different bits to get better results.

In general you want to use the highest speed that allows the bit to drill quickly and remove material.  High speed = cleaner holes.  Hard materials don't allow the bit to drill very quickly which means you must use a lower speed to prevent the wood from burning and toasting your bit.  If your bit changes color due to heat you've ruined it.  If you were using the correct type bit then next time use a slower speed.  If you weren't using the correct type bit then next time use the correct type bit and a slower speed.

Most drill presses use a pulley and belt system.  That's because there is no one right speed for a drill press.  It takes about thirty seconds to change the setting so get into the habit of doing it instead of being lazy and just going with however the drill press is currently set.

Drill Press Belt Combinations

Drill Bit RPM	Pulley on Motor	Pulley on Arbor	Materials
Low	Small	Large	Metals, low temperature plastics, hardwoods or any wood with deep or large holes.
High	Large	Small	Any material that will tolerate it.  Whenever possible drill plastics at high speeds but lower the bit slowly to shave the plastic for a very clean hole.

What I actually do when I really care about the quality of whatever I'm making is drill test holes until I find the drill press speed that achieves the best quality.  That is especially true when drilling holes with forstner bits into expensive hardwood.

Any time you're drilling a material that allows the bit to cut in quickly go with a higher drill speed.

If you're drilling metal or using a forstner bit then go with the small pulley on the motor and the large pulley on the spindle to lower the drill bit RPM.  Forstner bits drill very slowly and get very hot very fast.  If you use them on high speed you're going to have burnt holes.

Metal cuts slowly as well.  If you use high speed to cut metal you are going to over-heat the drill bit and ruin it.

Balsa, pine, spruce and other softwoods drill easily but also tear-out easily.  In this case you want inertia on your side.  By that I mean a slower drill speed will allow the wood to move instead of cut.  Assuming you're using a sharp bit all that tear-out you'll get on the face is due to using too low of a drill speed.  Tear-out on the back means you didn't use a sacrificial backer board.

By drilling soft woods at high speed the bit hits the wood and cuts it while the wood never saw it coming.  Instead of throwing it's fibers around to frustrate you they get cut cleanly.

Accuracy

If you really care about accuracy then a drill press is the way to go whenever possible.  If you need to drill holes in the firewall that's already glued into the fuselage then getting the whole thing rigged up under a drill press may be impossible or possibly just extremely difficult.  Your best bet will be to use a hand drill.  My rule is to drill any holes using a drill press as soon as possible to avoid situations where I have to use a hand drill.  For example, I always build (drill) my firewalls before I glue them into the fuselage.  It makes a huge difference in both accuracy and quality of the drilled holes.

When you're using any type of hand drill be it an electric drill, Yankee push drill or pin vise, the only way you will get consistently accurate holes is to have some type of guide in place before you drill.  That can be a center punch mark, a pin prick or even using a very small diameter bit in a pin vise to drill a slight hole into the wood.

For very precise work magnifying glasses such as reading glasses are extremely helpful.  I use them all the time and I'm amazed at how much difference it makes.  It's like somebody turned on the lights when I was working in the dark.  It really makes that much difference.

Using a hand drill, the softer the wood the less a center-punch is going to help you.  On hardwoods such as oak, maple and cherry a center punch is helpful but it's not a guarantee.  When you do use a punch don't hammer it like a nail.  Tap it to get a small indentation.  Place your drill allowing the punch to center the bit.  Now back off the drill slightly, bring it up to the lowest speed that's high enough to cut the wood.  Place the drill into the punched hole.  Before the drill cuts past the tapered point bring the drill up to its highest speed and continue drilling the hole.

If the speed is too low then the wood can grab the bit and move it off-center.  At this point it's almost impossible to get the hole centered again AND have a clean hole.

On any wood harder than balsa there is a better way to have clean, accurate holes.  It doesn't work on balsa because it's simply too soft to force a drill bit to do anything.

Drill a pilot hole that is much smaller than the finished hold.  For example, if you want to drill a 1/4" hole then drill a 1/16" hole first.  You don't have to drill all the way through but make sure the hole is at least as deep as half the diameter of the finished hole.  In this example, drill at least 1/8" deep using the 1/16" pilot bit.  Then drill the final 1/4" hole.

Using a Pin Vise is a little different.  For example, lets say I need to drill the holes for the mounting screws of a small, thin plywood hatch.  Again, I would use a drill press but if I couldn't then I can still drill very accurate clean holes.

For a hatch I will usually have four holes — one at each corner.  I use an accurate rule and sharp pencil to lay out the grid.  At each point I use a small needle (a sharp pin works) as an awl to mark the drill locations.  It's the same as center-punching but on a smaller scale.  Just put it exactly on the mark and push straight in then twist it back out.  You now have a small guide hole for a small drill bit.

Now that I have the guide I use a pin vise with a bit that's the finished size of the hole.  I don't drill a pilot hole because the sharp needle point provided a pilot.

The drill bit needs to be very sharp.  I don't put a lot of pressure on the bit when I'm drilling.  Instead I spin the bit as fast as I can and shave the hole.  Again, use a backer board to prevent tear-out on the back side of the hatch.

Remove the bit as often as necessary to clean out shavings.

When all the holes are finished I put the hatch in place where it will mount.  I usually have space around the hatch to allow for covering on the hatch itself and the part that it mounts to.  Plus I want the hatch to come loose when the screws are backed out so I want a small gap all the way around.  In other words, I don't want a press fit that requires the hatch to be pried loose when all the screws are removed.

So I cut some small strips of cardstock (business card) and slip them between the hatch and the hole where the hatch goes.  At this time I do want the hatch to get stuck in place so I use equal amounts of material all around it until it's wedged firmly in place.

Now I take the pin vise with the same bit and drill slightly into the wood that will receive the mounting screws.  It doesn't matter if you're using wood screws that bite into the wood or machine scews that will go through the wood and be secured with some type of nut.

If you're using wood screws then lightly mark all four corners with the drill bit and then remove the hatch.  Replace the bit with the appropriate bit for the screw and finish drilling the holes in the mount.

If you're drilling through then leave the hatch in place and continue drilling using the same bit you used to drill through the hatch.

Sharp bits are always important but if you use a pin vise it will be more readily apparent as you see the wood cutting cleanly instead of the bit grabbing wood fibers and tearing them away.  Electric drills of all types do the same thing with dull bits.

Manual Drills

These include brace drills, Yankee push drills, twist gimlets, Archimedes screw drills and pin vises.  My experience is limited mostly to pin vises although when I built my workbench I only had a Yankee push drill available with the included bits.  It wasn't the worst thing in the world but I would have preferred a power drill.

Generally speaking I use a manual drill when I need precision and a lot of control on a piece that can't be drilled using a drill press or is too difficult to get at or delicate to be drilled using an electric hand drill.  For example, almost every R/C airplane I've built required me to get inside the fuselage to drill a hole where there is no possible way a power drill would have fit even with a 90° attachment.

I use pin vises all the time and really like them.  I don't consider them to be a tool of last resort.  Rather they give me a lot more precision with small holes than I could ever get with any power drill or a Dremel.  In fact, I use pin vises so much that I have four of them that have a drill bit mounted semi-permanently.  All my pin vises have a pair of double-ended collets that go from 0.0" to 0.125".

I have mine set up with a wire bit (slightly less than 1/32"), 1/16", 3/32" and 1/8" because those are sizes I use very often and this way I'm not constantly taking the vises apart on both ends to get the collet I need and then putting it back together.  Frankly, it's kind of wasteful and lazy but the tool is inexpensive and small.  I would feel a lot worse about having four drill presses permanently set up to drill one hole size each.

Most pin vises have a swivel end so that you can brace it in your palm and twist or spin it between two fingers.  Having your magnifying glasses near your pin vises isn't a bad idea since they go well together.

All of mine have fairly poorly cut threads that hold both ends on so if I tighten them too much they're hard to get apart.  I have wiped all the parts of mine with a thin coat of sewing machine oil which has helped a lot.  I also put a drop of oil in the swivel so it turns better and doesn't squeak.  Obviously you don't want oil on your balsa so I rub it in and wipe it away from the outside.  This is a thin wipe all on the parts, you don't want them wet.

Lastly there are smaller pin vises that don't have collets at all.  The body is slit at the drill end in both directions to create four jaws.  It will fit what it will fit and nothing else.  They also don't have a swivel end.  These are made for very small wire bits (micro number drill bits) and intended to be used for very fine detail work such as drilling holes in the ends of wing guns on plastic model aircraft and that sort of thing.

Electric Hand Drills

My first drill was a huge corded 3/8" Craftsman that was a Christmas gift from my mother.  I was probably about age 15 and thought it was a great gift.

Unfortunately, it didn't take me long to learn that it was a great drill for the shop but a really poor one for model building.  It was just too large, heavy and unwieldy.  I don't have that drill any more but I wish I did.  Having a corded drill available is a good thing.  Don't get rid of your corded drill just because you have a snazzy new cordless drill that has a built-in GPS, iPod, work light, laser and titanium #2 Phillips driver.

You don't have to worry about batteries being charged and they have a lot more power than any cordless drill.  My Craftsman was a monster that could pretty much drill through anything.  I never did it but it would have disappointed me to find out that it couldn't drill a 2" hole 6" deep in solid concrete without a hiccup.

Don't buy anything cordless that has NiCad batteries.  Now that lithiums are widely available, cordless tools are using them too and they're worth the extra money.  I have two cordless drills and a cordless circular saw that are functionally dead.  The fact is they are good tools having nothing wrong with them except dead batteries.  The cost of replacement batteries is only slightly less than I paid for the tools in the first place.  The chargers didn't maintain the charge.  Once the battery on the charger was charged, the charger just let the battery go dead.

What that means is that the tools never had a charge when I needed them unless I thought ahead to unplug the battery and plug it back in.  Now I have three tools using four battery packs that won't take a charge.

Lithiums won't do that so they're worth the extra money invested.

Normally I go to places like Amazon.com to read reviews on whatever item I'm considering purchasing.  The drill I have now was needed the same day that I bought it because I don't have a corded drill any more and my other two drills were dead.  So I just purchased the least expensive lithium drill carried by Home Depot.  I have no complaints about it but if I could have waited I would have spent a lot of time reading reviews.

Not having done that I do like my little drill a lot.  For model-building, the smaller the drill the better.  It's just a lot easier to control when working on small model parts.  If you can't help yourself and have to do the Tim "The Tool Man" Taylor manly man thing and buy a drill having a V8 engine then don't expect good results on your models.

Drill Presses

Almost all drill presses have a true turning arbor — even inexpensive imports.  If the arbor doesn't turn true you need to return the drill press and get something else.  The problem with cheap drill presses is that they come with really crummy chucks.  I turned my sow's ear into a silk purse by purchasing an expensive chuck for my bench drill press.  The chuck cost twice as much as the drill press itself but it can hold the smallest bit that I have which is a very small diameter wire bit.  Even my model-builder's bench drill presses can't hold that bit without an adapter.

What prompted me to buy the chuck in the first place is that the stock chuck couldn't turn bits under 3/16" without a lot of run-out.  I had to loosen and tighten the chuck repeatedly to get the bit to turn true-ish.  Sometimes I couldn't get the bit to turn true at all.  The stock chuck couldn't hold a bit under 1/16" at all.

I do know how to tighten a chuck properly so if you're thinking the problem is that I put the key into one hole and tightened away you would be wrong.  When tightening the chuck on smaller drill bits you can actually see one of the jaws staying 1/16" to 1/8" higher than the other two.  So loosen, tap the chuck while holding the bit to lower the jaw, retighten, spin the chuck by hand, if it looks good turn it on, if it looks good then drill away.

The good news was that with the chuck removed the spindle turned very true so it was just a matter of finding a good replacement chuck.

Adapters used to hold small drill bits work (sort of) but they aren't precise.  It's much better to have a chuck that holds the bit rather than introduce more error with an adapter.

I've tried a couple of adapters to chuck small bits into a stock chuck that comes with various drills and drill presses.  The ones I've seen either have a 1/8" diameter round shank or a 1/4" hex shank.  Both that I have used worked pretty well but if you are trying to achieve extreme accuracy such as drilling a micro-hole dead-center in a piece of flat brass that is 1/16" wide then even if you get the piece accurately positioned under the bit the amount the bit is off center in the chuck or the run-out of the bit at the tip will cause you a lot of problems.

Also see

• How to Make a Fenced Drill Table for a Compound Table

Drill Bits

Drill bits are acquired over time as you need them.  I very strongly suggest you purchase two good sets of high speed steel twist bits — a fractional set from 1/16" to 1/2" and a numbered set from 1 to 60.

Drill bits dull and need to be replaced.  How fast a bit dulls depends on how much you use it, the materials you drill and whether you abuse it.  If you over-heat a bit you've trashed it.  If you drop it and it lands on the point you've trashed it unless you work over something soft like linoleum.

If you buy quality bits from a good vendor you can buy replacement drills for your set and the bits will be the same type as what originally came in the set.

There are a lot of drill bits available.  I have some specialized drilling tasks so have spent a lot of time reading up on various bits and have purchased many different types to find what does the best job and lasts longest.  I very strongly suggest you spend time learning how to use and perusing the online McMaster-Carr catalog.  There you will find a lot of things that are being sold to us by other outlets but at much higher prices.  While you're there search for Dremel bits and you will find just about everything available at very good prices.  I have several carbide bits that do a job far superior than anything Dremel makes at the prices are excellent.

Unless you have a very good reason, don't waste your money on various coated bits.  They don't do anything special for home, shop or model-building tasks.  If you have a machine shop then you already know a lot more about drill bits than I do and you are the people these bits are made for.

These are the bits I use but some of them are used for tasks other than model-building.

Drill Bits used for Model-Building and Model-Builder's Workshops

Fractional High Speed Steel Twist Bits

Purchase immediately.

Buy a set having bits from 1/16" to 1/2".  These are the drill bits most commonly available and most used by most everybody.  They also come with various coatings that really make no difference to us but may make the bits cost more.

Fractional High Speed Steel Brad Point Bits

Purchase as needed.

These make the cleanest holes in wood including wood products such as plywood, medium-density fiberboard (MDF) and chipboard.  Most hardware stores carry them in sizes 1/8" and up but don't carry odd sizes.  You can get better bits in more sizes from woodworking specialty stores such as Lee Valley Tools.

Buy brad point bits when you decide that you want to drill very clean holes.  The smaller brad points I've purchased are actually worse than twist drills but beginning at 3/16" the holes were noticeably better than with twist drills.

Numbered High Speed Steel Twist Bits

Purchase as soon as possible.

Until I met my machinist buddy, Joe, I had no idea what numbered drills were and I had a lot of problems because of it.  You will be very happy if you have a set of numbered bits and a caliper to go with it.  You can get a good digital caliper for around $30.00 and I think I've even seen them for about $20.00 but I'm not sure of that.

Numbered bits have all the sizes in between the sizes of fractional bits so when you need to drill a hole for an excellent fit such as drilling out a wheel for an axle where you want the wheel to turn but not wobble, numbered bits are the way to go.

I suggest you purchase these as soon as you can so you don't ever get in the habit of wallowing out holes in servo arms and such.  These bits come in sets with sizes that are very close together so you can find the exact right size you need.  That's why you need the caliper.

Numbered Micro Twist Bits

Purchase when needed.

I've purchased a couple sets of micro numbered bits.  These break easily and they're also easy to lose so I've gone through a couple of sets.  If you ever spill the bits or pull out more than one at a time that are close in size you're doomed unless you have a caliper.  One thing you can do is lay the bits side by side one a flat surface.  Place a straight bar over them.  The closer the bits are physically placed next to each other the more the bar will magnify the size difference.

If you use a lot of one size then you can buy them in bulk packs.  I've seen them in packs of six.

I don't use micro bits with my flying models very often.  They are mostly used when I build plastic models.  But if you make your own fittings such as rigging anchors on small flying models then you may need micro bits.

Twist Punches (Razor Hole Saw, Tube bits or whatever you want to call them)

Make as needed.

Ok, I don't know the name of these because they're shop made and make the very best quality holes in soft, thin materials such as thin sheet balsa.  There is no commercially available bit that can cut as clean a hole.  Brad point bits at very high speed with great care and lots of luck come close.

I have an article detailing how to make twist punches which you should as you need them.  It takes practice to get them really sharp but it's worth it.

Drill and Tap Sets

Purchase immediately.

I have a standard set of drill bits and taps.  You can get this or a similar set at any hardware store.  It comes with taps from 4-40 to 1/4-20 and a drill bit for each tap plus a handle.  You definitely need this set.  In addition I purchased a 2-56 drill and tap set.

Used for Shop Tasks other than Model-Building

All of these fall under the purchase as needed category.

High Speed Steel Tapered Wood Screw Bits

I also have a set of taper wood screw bits.  It came with seven bits, dedicated countersinks (the best countersinks I have ever used) and depth stop collars.  The set was a little over $100.00.  Pricey but I like them a lot.

Forstner Bits

I also have a set of inexpensive imported forstner bits.  I don't use them often but I do need them often enough to own them.  Just not often enough to buy a $300.00 set.

Forstner bits drill clean flat-bottom holes.  In other words, they are used for counter-boring.  Normally this means that something with a flat surface goes into the hole which is why you can't use a normal twist bit which leaves a conical shaped hole-bottom.

For example, I mostly use forstner bits when I'm going to put some type of bolt or a nut into the hole.  This may be a normal bolt with a washer or a carriage bolt in situations where the bolt must be at or below flush with the surface.

Saw Bits

These are generally used for large diameter holes through materials no thicker than the saw can cut.  That usually means boards such as door, table tops, etc.  They are inexpensive and work very well although they don't make the cleanest holes.  They put less load on the drill than most other bits of the same diameter.  However, they only cut the perimeter and don't remove the middle.  These bits have a twist drill in the center that enters the wood before the saw to act as a pilot.  I suppose if you were really good with a chisel you could get a flat-bottom hole but that's really not what they're for.  Hole saws cut through-holes.  Forstner bits cut flat-bottom holes or through holes but cost a lot more than hole saws.

The other thing saw bits do is make wheels.  The axle hole will be at least as large as the pilot bit centered in the saw bit but it can be enlarged if necessary or bushed to make it smaller.  The piece is usually accurately round enough for toys and such.

These bits heat up very quickly and will leave burns on the wood.  If you care about that or want your bit to last then you'll need to recognize when the bit is getting too hot, stop and remove the bit from the work to let it cool before starting again.

Spade Bits

I really haven't figured out what these are good for.  I've never gotten good results with them but the few times I used them was when I couldn't afford the right type large diameter bit.

Masonry Bits

Used to mount things on my cinder block shop wall.

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