Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => AmpTools/Tech Tips => Topic started by: PRNDL on May 27, 2009, 01:47:36 pm

Title: My drill keeps skipping with philips screws
Post by: PRNDL on May 27, 2009, 01:47:36 pm
My drill keeps skipping (is that the right term?) with Phillips head screws.

The same problem occurred with an Ace Hardware battery drill, but it seems worse with the new DeWalt. It has 2 speeds and 12 torque settings.

What settings do you use?

I seem to have fallen asleep during Drilling 101 in college.
Title: Re: My drill keeps skipping with philips screws
Post by: G._Hoffman on May 27, 2009, 04:47:42 pm
What kind of screws, in what kind of material?  With wood screws (real wood screws, not drywall screws), you are going to need to drive them by hand the first time - though it can help to drill your pilot hole (you ARE drilling pilot holes, right?) a 1/64" oversized, and it helps a LOT to wax the screws with some paraffin wax before you drive them the first time.  If you MUST use a driver, get one of those electric screwdrivers (not a hand drill).  They run at much slower speeds, which helps - but I still prefer to drive them by hand the first time.  With machine screws, you need to tap the hole first, and should probably drive them by hand, at least for the last couple of threads.  With sheet metal screws, you should be OK with your drill, but make sure you drill a pilot hole, and are using the right sized bit - it matters a LOT.  Actually, you should just be careful about the bit, no matter what.

Actually, aside from sheet metal screws (in sheet metal), and dry wall screws for very rough work, I just prefer to drive screws by hand.


Gabriel
Title: Re: My drill keeps skipping with philips screws
Post by: FYL on May 27, 2009, 06:01:47 pm
Quote
My drill keeps skipping (is that the right term?) with Phillips head screws.

Phillips or Posidriv? Maybe you're using the wrong bit...

Check http://en.wikipedia.org/wiki/Pozidriv
Title: Re: My drill keeps skipping with philips screws
Post by: tubesornothing on May 27, 2009, 07:31:14 pm
Try some different bits.  Some are better than others.  When doing a new build, a bit a soap on the screw goes a long way.
Title: Re: My drill keeps skipping with philips screws
Post by: PRR on May 27, 2009, 10:50:31 pm
> I seem to have fallen asleep during Drilling 101 in college.

Screwing 101!

Phillips are designed to slip out.

You need serious pressure on the bit.

A worn bit is hopeless.

If you really wanna DRIVE screws, use Robertson.
Title: Re: My drill keeps skipping with philips screws
Post by: G._Hoffman on May 27, 2009, 11:37:34 pm
If you really wanna DRIVE screws, use Robertson.


Or Torx.



Gabriel
Title: Re: My drill keeps skipping with philips screws
Post by: PRNDL on May 28, 2009, 01:30:57 am
Almost anything slips - today it was Fender chrome screws for the back panel of an amp - all the holes were already there. I replaced them with new T-screws and had the same issue.

Extra pressure does help, as does orienting the drill just right, but even then it will usually skip out.

Maybe it's time for a new bit. I didn't think of that.

I'm also wondering about the battery - they don't seem to last long, even with sporadic use.

After listening to the advice on my last post about this, I ordered a 10,000µF/50V can and plan on charging it to 15V for the 12V battery.

Thanks for the advice!!!

It seemed like a silly question, but I figured that other people may benefit.
Title: Re: My drill keeps skipping with philips screws
Post by: PRR on May 28, 2009, 02:26:39 am
> Maybe it's time for a new bit.

In power-drive application, Phillips bits should be considered disposables. When in doubt, throw it out.

You do know that Phillips comes in several sizes? The wrong size is useless, unless you are just spinning-down screws loosely. The bit should be snug.

Pozidriv looks like Phillips, "can" be driven with Phillips' driver, but is really quite different. Used with a Pozidriv bit, it won't cam-out.

Good screwing is as fussy as good playing. You choose your strings carefully, you discard your pick when it seems frazzled. Ya gotta screw carefully too.
Title: Re: My drill keeps skipping with philips screws
Post by: LooseChange on May 28, 2009, 05:14:05 am
If my screwdriver slips, I change the bit. Strippin' is for printers and some girls.
Title: Re: My drill keeps skipping with philips screws
Post by: Dynaflow on May 28, 2009, 07:59:20 am
 Like PRR said, they come in different sizes, you want to find the one that fills the slots completely and rests perfectly in the slots. To small  rounds out a hole in the middle, to big and it either won't go into the screw at all, or will slip out with very little torque.

Regards,

Dyna

Ps: There you go, screwing 101... go to the head of the class.  ;D
Title: Re: My drill keeps skipping with philips screws
Post by: G._Hoffman on May 28, 2009, 12:44:40 pm
Particularly with the relatively short screws on most amps, your best bet is to screw by hand.

Yes, a new bit helps.  Yes, the right sized bit or screw driver is essential, but you will always have more control by hand.  Sure, it's a PITA, but its the way to go.  I will admit to sometimes using the little electric screwdrivers (much different than an electric drill, in that they are far less powerful, and slower), but even then I always drive things the last few threads by hand.



Gabriel
Title: Re: My drill keeps skipping with philips screws
Post by: supro66 on May 29, 2009, 10:04:52 am
Try some different bits.  Some are better than others.  When doing a new build, a bit a soap on the screw goes a long way.

(http://i282.photobucket.com/albums/kk243/supro66/MACHRINERY%20TOOLS/bit22.jpg)

MY TUBE AMP SITE

http://www.geocities.com/insp/SUPRO6420.html
Title: Re: My drill keeps skipping with philips screws
Post by: dBDoctor on May 29, 2009, 10:36:02 pm
I've found it very important for hard materials that once you start the screw, take your non-trigger pulling hand and brace yourself against the back of the drill, and use your body weight. When using proper technique and bit/drill, reduced torque settings are rarely necessary
Title: Re: My drill keeps skipping with philips screws
Post by: Manic on May 31, 2009, 05:19:28 pm
I have averaged around 50 guitar repairs a year over the last 20 years, mostly electrics. As it turned out, I have found that all Phillips bit screw drivers aren't created equally. As PRR stated "Phillips are designed to slip out." ..... I noticed!

I have a habit of buying tools, as I'm sure many of Us here do. A #2 and #1 Phillips are the usual electric guitar sizes. When working on a customers guitar, it goes with out saying that I'm not interested in a Phillips bit that is prone to jumping out of a pick guard screw and gouging a huge gash across the top of a guitar. You do have to lean on a Phillips to get it bite.... I use hand driver when working on guitars for control. No power-drive accidental over-reving trashing screws, wood, bits ect.  Not acceptable....
 
anyway, out of most all the screw drivers I have tried over the years, I dig Wiha. http://www.wihatools.com/300seri/311serie.htm. One of the cheaper models. They seem to settle into a screw better than other drivers for some reason. Noticeably. They have a VERY positive feel when seated. Pretty cheap to boot. I'm not sure way they work better (designed by Germans), but they do. Looking at the tip of a #2 Wiha, nothing special...well made looking.
I have bought screw drivers that brand new, didnt seem to fit any sized screw very well, wierd and pretty much worthless.
You can tell how good a screw driver is when Ya go after a screw that has been previously screwed to death. A Wiha seems to have an edge in that situation too. I'm sure their are many great screw drivers...pound for pound the Wiha stands out to Me.

I'm interested in seeing if the power-drive style bits are as impressive as the hand drivers. I use power-drive style bits building amps. I plan to find out.

FWIW. C. Smith