Wow. I'd never heard of those. Looks pretty cool. Thanks for the link. I
can use that for another project.
For this application, however, the hole isn't round. A double-D punch
produces a hole that is flat on two sides. The connector is also flat on
two sides and is, therefore, prevented from spinning in the hole.
73,
Michael - N6MEF
-----Original Message-----
From: Roger (K8RI) [mailto:K8RI-on-TowerTalk@tm.net]
Sent: Wednesday, October 15, 2008 2:00 PM
To: hinrgdj1@comcast.net
Cc: Michael E Fox (N6MEF); towertalk@contesting.com
Subject: Re: [TowerTalk] N-connector double-D punch
hinrgdj1@comcast.net wrote:
> An annular cutter is quicker and smoother...
>
> http://www.blairequipment.com/Rotabroach_Cutters/rota_cutters.html
>
> A small fractional set can be had on Epay for ~$70...very handy shop tool!
>
>
I had forgotten about those. They do an excellent job, work better than
a hole saw, give a professional looking cut even when used with a hand
drill (if the arbor fits the hole, or is self drilling)
However in their comparison photo the drill hole will look far better if
they start with a small pilot hole and then work up. It will come out
"round" and with only a small burr. Admittedly that takes a lot longer
and much more care, but it works if you don't have a broach on hand, or
don't want to wait for one to be delivered.
73
Roger (K8RI)
> Mike K4EAR
>
> -------------- Original message ----------------------
> From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
>
>> Michael E Fox (N6MEF) wrote:
>>
>>> I'm looking for what's called a "double-D" punch that is the correct
size
>>> for N-type connectors. This will be used to punch holes in bulkheads
for
>>> installing either PolyPhaser DSXL lightening arrestors or N-type
Amphenol
>>> bulkhead pass-through connectors.
>>>
>>>
>> I normally use Greenlee "knockout punches". The latest style split the
>> piece knocked out into two haves that look like the letter "D", but I've
>> never seen them called "double D".
>>
>> OTOH material for bulkheads is normally thick enough I just use a drill
>> bit of the proper size, be it in steel or aluminum. IOW it's a rather
>> small hole and punches for that size use a relatively small through bolt
>> (bout 1/4" to 5/16") that can be broken trying to punch holes in 1/8" to
>> 1/4" thick, Aluminum, Copper, or steel. I've busted the bolts on chassis
>> punches for tube sockets, let alone this size and thickness. Drill the
>> hole undersize, then work up to the proper size one drill at a time.
>> This gives a hole with relatively clean and smooth sides however don't
>> forget to debur the inside and outside. BTW the hole for the through
>> bolt on most of the punches is as large or larger than the bulkhead
>> connectors for N or UHF. (Same size IIRC)
>>
>> 73
>>
>> Roger (K8RI)
>>
>>>
>>>
>>> Greenlee doesn't make a double-D that is small enough and I'm having
>>> difficulty finding the right size anywhere.
>>>
>>>
>>>
>>> This must exist somewhere. Anyone know where to find one?
>>>
>>>
>>>
>>> FYI - if you don't know what I'm talking about, then Google "double-d
>>> punch". You will find many out there, most notably Greenlee. But I
haven't
>>> found any that have the right dimensions for a standard N-connector.
>>>
>>>
>>>
>>> Regards,
>>>
>>> Michael / N6MEF
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|