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jedi killer
04-07-2008, 10:01 PM
i don't understand why they have a tap hole drill handle on here can a tap hole be drilled by hand??

Hasid Lafre
04-08-2008, 02:12 AM
I would use the tap handle

Arm on Fire
04-08-2008, 05:14 AM
The hole cannot be drilled by "hand" but you can use a hand drill and a steady "hand"
the tap handle is to hold the tap. after drilling the hole you use the tap to thread the hole, and the tapping should be done by hand.

xwingband
04-08-2008, 05:14 AM
i don't understand why they have a tap hole drill handle on here can a tap hole be drilled by hand??

Yeah... you drill the first pilot hole though, that's not by hand. It's smaller than the tap and when you are actually using the tap you're just cutting the threads.

Ghostbat
04-08-2008, 10:05 AM
I will add here that if you use a tap in a power drill and don't do it by hand odds are you are just going to enlarge the hole rather than thread it and possibly ruin the tap in the process.

The process is, Drill a hole, then run the tap through to cut the threads that the screw will screw into.

Kant Lavar
04-08-2008, 12:17 PM
Ironically enough, this answers the exact question I was going to ask at a later point (revising my saber design with a second switch to take full advantage of Crystal Focus - still can't figure out how the hell I'm supposed to mount additional LEDs for clash and/or shimmer effect, though).

jedi killer
04-08-2008, 03:20 PM
okay that makes sense so you could use a really strong power drill and do it? then cut the threads in with the tap handle

xwingband
04-08-2008, 04:04 PM
okay that makes sense so you could use a really strong power drill and do it? then cut the threads in with the tap handle

That's the idea. With small threads you do them by hand to avoid problems. A drill has more power and could just ram through any debris and cut a larger hole instead of threading it. The debris might also jam the tap and snap it. I've done that by hand so with a drill you wouldn't even feel the resistance before it snaps.

xl97
04-08-2008, 05:25 PM
The debris might also jam the tap and snap it. I've done that by hand so with a drill you wouldn't even feel the resistance before it snaps.


very true.. remember to back off somewhat..instead of going round and round straight through.. ;)

acerocket
04-08-2008, 06:08 PM
I have broken more taps in my time than most of you will drill and tap holes in your life. I recently finished a project with over 650 4-40 threaded holes in .25" thick aluminum plate - and I only broke 1 tap in the process.

The first step in tapping a hole is to actually have a hole. Usually when you buy the tap, it will say on the package what size pilot hole to drill. If not, there are many resources on the net that will help (google tap drill chart). Of course you can drill the hole any way you want but the more accurate the hole, the better the threaded hole will be. A drill press and vice would be the best way, a small hand drill would work also if you are careful.

After the hole is drilled, you then use the tap - in the tap handle- to thread the hole. Thread cutting oil is a must if you want nice threads and to keep the tap from breaking. WD-40 works good in aluminum. There is a product called Tap-Magic that is very good for threading holes. They sell a version for aluminum and one for steel.

Take it slow and keep the tap as straight as possible. Everybody has their own way of tapping. I usually turn the tap 1 full turn, then back it up 1/2. Then repeat all the way in. Unless the hole is very deep, you don't really need to bring the tap out of the hole and clean it (the tap and the hole). Just make sure to keep the tap oiled. I usually squirt a little WD-40 on after every 4th or 5th complete turn of the tap.

Because most taps are tapered at the tip, you need to make sure you go completely through the hole and then some to ensure clean threads are cut all the way through.

The reason most taps break is not because the material is too hard, but because the user has bent the tap over as they are threading the hole. Trust me, if you are going to break a tap because the material is to hard or the pilot hole is too small or the tap just gets stuck, you will know (and if you are watching for it, you should be able to stop before breaking the tap). It is especially important with small taps to make sure you keep the tap square to the workpiece and not to twist it at an angle. There is a reason most taps are broken on the way out as opposed to the way in. Because you are usually turning out the tap faster and are more likely to tweak the handle and snap off the tap.

Using a drill to thread the hole is a big no no. All you will do is make a bigger hole and no threads. CNC mills and lathes can thread holes with taps, but they require special tap holding fixtures to keep the tap from being rigid.

Dark Helmet
04-08-2008, 08:08 PM
Ace, that's GREAT advice! I recently broke a tap in my blade holder, but luckily it was to be heavily weathered, so I dremeled it flush and looks like it belongs....turns out the problem was not properly sorting my drill bits so the hole was too small. BIG LESSON LEARNED! next time i will def use wd-40 in stead of "going in dry".... I knew better but I got impatient...the first road to a mistake.

DarthFender
04-09-2008, 11:35 AM
Impatience leads to Anger.
Anger leads to hate.
Hate leads to suffering.

Or something like that.