Homebrew_PCBs

Afternoon all.

I've made a couple of attempts at etching/drilling and have had a few
tracks lift during drilling.

I've always lacquered before drilling and I'm beginning to think this
should be left until after I drill.

Any other issues that could be causing this? I suppose the key is
super sharp bits. PS: I'm using a 20k RPM 'dremel' like tool and non-
tc drill bits (yet). Have yet to find a source for them in Australia.

Adam

In a message dated 11/30/2003 9:13:18 PM Central Standard Time,
adam_j_bradley@... writes:
Any other issues that could be causing this? I suppose the key is super
sharp bits. PS: I'm using a 20k RPM 'dremel' like tool and non-tc drill bits
(yet). Have yet to find a source for them in Australia.
Adam: I don't know if the "Dremel" you have is ACTUALLY a Dremel, but the
couple I have had do not have NEARLY precision bearings to properly drill fine
holes in glass-epoxy for PC-boards! I use ONLY carbide "PCB drill-bits", all
with 1/8" (3.175 mm.) dia. shanks. Few of these smaller than 3 mm drill-size
would stand up for long with the junky bearings all the Dremel-like tools I
have seen running things! (I built my own "quill" using a 400 Hz precision motor
and ABEC-7 bearings, with a 1/8" dia. collet).

Also, I drill FIRST (I built my own computer-controlled X-Y PCB-drill rig — I
am still TRYING to figure out how to upload a photo of it in PHOTOS section
of this group — for now, I will just e-mail YOU one, separately. I once
drilled "after etch", when I didn't have this rig built, but I ALWAYS used
super-sharp (i.e., "fresh") drill-bits, never DULL ones. HSS bits will go dull in
glass-epoxy after two or three holes! ONLY carbide will work for hundreds of
holes, and THEN, only in proper equipment, NEVER in a "sloppy" Dremel!

Sorry, Los Angeles is the closest I have ever been to Australia — oh, wait:
Is Aquitlapilco, Mexico closer-yet? So I can't help you with bits. AND, I
have bought all I need in boxes of 50, "on sale", when vendors offer them---
when a PC-firm resharpens to the point the bits are too short to go through seven
layers (about 11 or 12 mm.), they are "done" with 'em, and they are offered
reasonably in boxes of 50. SAVE all the 1/8" dia. shanks when the delicate bit
busts off, and re-grind as ENGRAVING bits! JAMECO and JDR Microdevices are
two firm-names in L.A., CA (or near there) that come to mind.

Lotsa luck! Hopefully before I have played my last digerydoo recital, I will
visit AUS, one day!

Regards! Jan Rowland


[Non-text portions of this message have been removed]

Adam Bradley wrote:

> Afternoon all.
>
> I've made a couple of attempts at etching/drilling and have had a few
> tracks lift during drilling.
>
> I've always lacquered before drilling and I'm beginning to think this
> should be left until after I drill.
>
> Any other issues that could be causing this? I suppose the key is
> super sharp bits. PS: I'm using a 20k RPM 'dremel' like tool and non-
> tc drill bits (yet). Have yet to find a source for them in Australia.

Farnell have them and Radio Spares might. They all have 1/8" shank.
A board house will give you some if you ask right;)
Mektronics in melbourne might have some: http://www.mektronics.com.au/
http://www.computronics.com.au/tools/

With the thin steel drills, you might as well be boring
with a knitting needle.

--- In Homebrew_PCBs@yahoogroups.com, JanRwl@A... wrote:

> In a message dated 11/30/2003 9:13:18 PM Central Standard Time,
> adam_j_bradley@y... writes:
> Any other issues that could be causing this? I suppose the key is

super

> sharp bits. PS: I'm using a 20k RPM 'dremel' like tool and non-tc

drill bits

> (yet). Have yet to find a source for them in Australia.
> Adam: I don't know if the "Dremel" you have is ACTUALLY a Dremel,

Try to separate your reply. It hurt my eyes to look for where the
quoted left off and yours started. :'/

> Also, I drill FIRST (I built my own computer-controlled X-Y

PCB-drill rig â€" I

> am still TRYING to figure out how to upload a photo of it in PHOTOS

section

> of this group

Sigh... you've had it uploaded forever! I moved it and resized to a
more reasonable size. If you upload to Photos, all anyone will see is
a tiny 300x400.

It's here:
<http://groups.yahoo.com/group/Homebrew_PCBs/files/Homemade%20PCB%20equipme=
nt/>

> drilled "after etch", when I didn't have this rig built, but I

ALWAYS used

> super-sharp (i.e., "fresh") drill-bits, never DULL ones. HSS bits

will go dull in

> glass-epoxy after two or three holes! ONLY carbide will work for

hundreds of

> holes, and THEN, only in proper equipment, NEVER in a "sloppy" Dremel!

I concur. Sharp, sharp, sharp. I have a drill bit resharpener for my
regular bits, but I don't think it'd last long on carbide.

Doesn't Think and Tinker offer resharpening?

Steve