The constant diameter bits are usually HSS, you can use them with the
jacobs chuck with no problem. They bend much more before breaking but
don't stand up well when drilling glass fiber.
Carbide drills mostly come with the 1/8" shank, and should be used
with the collet. There are probably carbide drills with thin shanks,
but I am not aware of any solution for that. I have never seen collets
other than the standard set.
If you want them cheaper, simply buy second hand drills the PCB house
has thrown out or resharpened ones. They are still good for many many
holes and surely cheaper than any new bit.
ST
On Sat, Feb 4, 2012 at 3:18 AM, Steve <steve65@...> wrote:
> Thanks for the advice guys. I've seen the bits with the 1/8in shanks and
> my first thought was to not use them because they cost 2 or 3 times more
> than the constant-diameter bits. And I'm thinking these bits break
> easily and so replacement cost is something to keep in mind. Hence my
> inquiry re collet or perhaps a chuck for bits under 1mm in diameter.
>
> Steve K8JQ
>
> On 2/3/2012 7:36 PM, John Anhalt wrote:
>> All of my small carbide bits for PCB work have 1/8" shanks.
>>
>> John
>> ----- Original Message -----
>> From: Branko Badrljica
>> To: Homebrew_PCBs@yahoogroups.com
>> Sent: Friday, February 03, 2012 9:10 PM
>> Subject: Re: [Homebrew_PCBs] Proxxon 38128 drill press -- collets for small bits?
>>
>>
>>
>> Dne 03. 02. 2012 23:02, pis(e Steve:
>> >
>> > Hi all,
>> >
>> > A couple of weeks ago I inquired about small drill presses for PCB work.
>> > I'm kinda leaning toward the Proxxon 38128. Looks like the drill press
>> > comes with six collets, the smallest of which accommodates 1/32in (about
>> > 1mm) shank size.
>> >
>> > I'd like to be able to use a #76 bit and perhaps a #78 bit with this
>> > drill press. Anyone know if collets are available for the 38128 for
>> > those smaller size bits? If so, what is the source?
>> >
>>
>> This is not AFAIK meant for PCB work. It's for general-purpose work.
>>
>> I use drill stand MB 140/S (NO 28606) + IB/E drill/grinder ( NO 28481).
>>
>> Drill stand has extra bolt for elimination of air gap and it's very precise.
>> IB/E drill unit has high yuality bearings and can achieve high rpms,
>> needed for PCB drilling with hard drill bits.
>>
>> Regards,
>>
>> Branko
>>
>> >
>> > Thanks.
>> >
>> > Steve K8JQ
>> >
>> > --
>> > Read The Patriot Post Vertitas vos Liberabit
>> > http://patriotpost.us/subscription/
>> >
>> >
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
>>
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
>> ------------------------------------
>>
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>>
>>
>>
>>
>
> --
> Read The Patriot Post Vertitas vos Liberabit
> http://patriotpost.us/subscription/
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
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