Micro Drill Bits

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Posted on November 24, 2022 at 14:28:15

Jonesy
Audiophile

Posts: 3156
Location: Winnipeg, Manitoba
Joined: September 1, 2005
Contributor
Since: March 1, 2018

These micro bits come in handy for cleaning out PCB holes that still have some stubborn solder in them. For me they work much better than needles or dental picks because they actually carve the solder out as opposed to forcing the hole bigger. Especially good for those plugged through board connections.

The kit I bought came with a screwdriver-like handle with an adjustable chuck. This is perfect when you want to be a little more delicate and don't want to resort to high RPM's of a Dremel. Just a few turns by hand is often all you need to bore out the solder.

If you plan to use a Dremel, be sure to check if your chuck can tighten that small. I already had a second smaller chuck size on hand so it worked out OK.

The chuck on the screwdriver tool that comes in some micro bit kits is removable and looks very similar to the Dremel's. In my case it did not fit the Dremel but sure came close.

I cheaped out and bought my set online quite a few years ago from AliExpress and the quality has been fine so far. Otherwise Amazon carries quite a few brands to choose from. Not sure about in person shopping but likely hardware or craft stores carry them.

My last use (pic of my Dremel) was to drill a new hole for a Christmas ornament. Maybe Santa will bring me something special under the tree.

Jonesy

"I know just enough to get into trouble. But not enough to get out of it."

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RE: Micro Drill Bits

pictureguy

22:19:24 01/27/23

RE: Micro Drill Bits

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09:54:39 01/04/23

RE: Micro Drill Bits

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22:22:38 01/27/23

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RE: Micro Drill Bits

pictureguy

22:19:24 01/27/23

RE: Micro Drill Bits

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09:54:39 01/04/23

RE: Micro Drill Bits

pictureguy

22:22:38 01/27/23

Warning

DDzStereo

03:58:22 12/09/22

RE: Warning

Jonesy

08:18:07 12/09/22

RE: Micro Drill Bits

pictureguy

21:57:58 12/01/22

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RE: Micro Drill Bits

Jonesy

08:11:05 12/02/22

RE: Don't worry about material hardness

B. Scarpia

09:38:46 12/03/22

RE: Micro Drill Bits

SgreenP@MSN.com

19:33:00 11/25/22

for PC boards

Story

04:16:41 11/25/22

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RE: for PC boards

Mike B.

09:30:50 11/25/22

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RE: for PC boards

Story

15:44:06 11/25/22

RE: for PC boards

pictureguy

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RE: Micro Drill Bits

B. Scarpia

01:52:03 11/25/22

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rogerh113

07:01:28 11/25/22

5

Stubborn Solder

Jonesy

08:41:44 11/25/22

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RE: Stubborn Solder

rogerh113

08:46:07 11/25/22

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RE: Stubborn Solder

Jonesy

13:34:31 11/25/22

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RE: Ebay Link

B. Scarpia

07:33:57 11/26/22

RE: Ebay Link

Jonesy

12:02:05 11/27/22

RE: Micro Drill Bits, posted on November 25, 2022 at 01:52:03
B. Scarpia	Or you can learn to "scrub" the solder wick like us old-timers do and not potentially damage the eyelet.

for PC boards , posted on November 25, 2022 at 04:16:41
Story Audiophile Posts: 10427 Location: NJ Joined: December 11, 2000	and delicate operations you can also use a hand held small bit chuck and twist with your hand

RE: Micro Drill Bits, posted on November 25, 2022 at 07:01:28

rogerh113
Audiophile

Posts: 506
Location: San Francisco South Bay
Joined: October 20, 2014

I am a long time user of solder wick as well. Recently I have run into problems, I think because of the nature of solder used on circuit boards after the '70s. Some of that rubbery garbage will simply not wick out of a feed through, even after multiple uses of flux and additional 'good' solder to thin out the rubbery garbage. Several times I have had to resort to a pin to puncture through the thin sheet remaining in the center of the feed through. Otherwise getting to trace lifting time, which is another bad thing.

If you have a solution to lifting the crap rubbery solder, then I would really like to know about it. All part of the craft, I think...

Stubborn Solder, posted on November 25, 2022 at 08:41:44

Jonesy
Audiophile

Posts: 3156
Location: Winnipeg, Manitoba
Joined: September 1, 2005
Contributor
Since: March 1, 2018

It's that stubborn solder (usually leadfree) on newer boards that I've found the tiny drill bits and handheld mini chuck to be particularly useful.

Especially when there is barely any room to work with to get in a solder sucker or any other of the most common ways to ease out the old stuff.

Can often get away with making a tiny hole just big enough to get the new part in.

Here's a pic of the mini hand held chuck and some bits along with diode leads and tube pins for scale. Some really small bits in there for even smaller pilot holes.

Jonesy

"I know just enough to get into trouble. But not enough to get out of it."

RE: Stubborn Solder, posted on November 25, 2022 at 08:46:07
rogerh113 Audiophile Posts: 506 Location: San Francisco South Bay Joined: October 20, 2014	Yep, I can see the value of something like that. Only manually operated though - forget anything motor driven. You have a link for where you got that?

RE: for PC boards , posted on November 25, 2022 at 09:30:50
Mike B. Audiophile Posts: 26352 Location: OR Joined: September 27, 1999 Contributor Since: September 1, 1999	That is what I use. My problem is I break the tiny drill bits.

RE: Stubborn Solder, posted on November 25, 2022 at 13:34:31

Jonesy
Audiophile

Posts: 3156
Location: Winnipeg, Manitoba
Joined: September 1, 2005
Contributor
Since: March 1, 2018

The order was actually from Amazon but the link states "Currently Unavailable". Too bad because it was a lot less expensive then, and shipping was free.

Is currently available on Aliexpress, but the price has since gone up and shipping may be extra depending on your location. *** Edit. Seller rating not steller either but link below for info. ***

What I liked about this set in particular was that the sizes went down really small. As tiny as .3mm.

Note that I just did a quick search on eBay, and though not exact, they look pretty good at prices closer to what I paid awhile ago. Unfortunately I can't comment on them personally. Plenty of reviews though. Just search for "mini hand twist drill bits" on eBay.

Jonesy

"I know just enough to get into trouble. But not enough to get out of it."

Hand Drill Set

RE: for PC boards , posted on November 25, 2022 at 15:44:06
Story Audiophile Posts: 10427 Location: NJ Joined: December 11, 2000	yea, I've broken a few. Once you break one you realize you must be much more careful. And then later on you break another one. People who use them every day are at an advantage

RE: Micro Drill Bits, posted on November 25, 2022 at 19:33:00
SgreenP@MSN.com Audiophile Posts: 3537 Joined: April 23, 2007	I sand down my dogs toenails with it

RE: Ebay Link, posted on November 26, 2022 at 07:33:57

B. Scarpia

You can never have too many tiny tools to roll under the bench, never to be seen again.

I bought'm.

10 Bucks USA Vendor

RE: Ebay Link, posted on November 27, 2022 at 12:02:05
Jonesy Audiophile Posts: 3156 Location: Winnipeg, Manitoba Joined: September 1, 2005 Contributor Since: March 1, 2018	Those look great! Jonesy "I know just enough to get into trouble. But not enough to get out of it."

RE: Micro Drill Bits, posted on December 1, 2022 at 21:57:58
pictureguy Audiophile Posts: 22597 Location: SoCal Joined: October 19, 2008	What is the size range? Available in HS steel? Too much is never enough

RE: Micro Drill Bits, posted on December 2, 2022 at 08:11:05
Jonesy Audiophile Posts: 3156 Location: Winnipeg, Manitoba Joined: September 1, 2005 Contributor Since: March 1, 2018	There are a couple of posts with a link near the end of the thread that have descriptions of sizes and bit material. Both warn not intended for drilling through anything too hard. Jonesy "I know just enough to get into trouble. But not enough to get out of it."

RE: Don't worry about material hardness, posted on December 3, 2022 at 09:38:46
B. Scarpia	They arrived the other day; the set of 8 Micro-bits in their nice case are too pretty to use. The bag of larger sizes look like the usual one and done cheapos.

Warning, posted on December 9, 2022 at 03:58:22
DDzStereo Audiophile Posts: 206 Location: North of Toronto, Ontario Joined: July 1, 2009	Use drill bits with extreme caution. If the diameter is too large you can destroy the pcb via which can/will cause serious problems on multi layered boards.

RE: Warning, posted on December 9, 2022 at 08:18:07
Jonesy Audiophile Posts: 3156 Location: Winnipeg, Manitoba Joined: September 1, 2005 Contributor Since: March 1, 2018	For sure and thanks for pointing that out! On the flip side I've used bits much smaller than the original hole and with careful centering open it up just enough for the new part to fit in. No disturbance to the board but the key is patience and use the manual hand drive in delicate areas. Jonesy "I know just enough to get into trouble. But not enough to get out of it."

RE: for PC boards , posted on December 14, 2022 at 21:35:41
pictureguy Audiophile Posts: 22597 Location: SoCal Joined: October 19, 2008	Many years ago I had such a hand chuck and got good with it. Most frequently used bit was 0.050" the smallest in a conventional set...... Too much is never enough

RE: Micro Drill Bits, posted on January 4, 2023 at 09:54:39

gusser
Audiophile

Posts: 3649
Location: So. California
Joined: September 6, 2006

As someone who designs PC boards, this is a very bad idea. The warning about plate through holes (vias) and worse yet, multilayer boards should be heeded.

What you need is a powered vacuum desolder station. Yes they are expensive, over $500. But destroying a board in say your DAC is far more expensive.

One thing that might help, and is also what I do even with the desolder station, is to add more solder to the pad, then remove it. Sometimes solder wick is enough.

Note that many boards today use lead free solder which is especially difficult to remove.

RE: Micro Drill Bits, posted on January 27, 2023 at 22:19:24
pictureguy Audiophile Posts: 22597 Location: SoCal Joined: October 19, 2008	In my kit? Standard drill case goes to .050" while in my 'secret stash' I have .035" and .028" which I had use for at one time..... I don't think either of the smaller bits would be properly gripped in my 3/8" Makita..... Too much is never enough

RE: Micro Drill Bits, posted on January 27, 2023 at 22:22:38
pictureguy Audiophile Posts: 22597 Location: SoCal Joined: October 19, 2008	What about my ancient pump-action Solder Sucker? Once-upon-a-time, that was my first choice for some more delicate work...... And yes, I've got about 100 feet of solder wick on those little micro spools.... Add / Remove is sound practice. Lead Free is a CURSE. Too much is never enough

Tweakers' Asylum

Micro Drill Bits

50.72.89.155