To avoid these ads, REGISTER NOW!

Panel punch for BNC terminals?

pancho400cid

Well-known member
Joined
Sep 26, 2014
Messages
4,521
Location
Austin, TX
Hey guys -

This is a work thing and probably a longshot but here goes.

I need to mount the BNC connectors in the first pic to a subpanel. You can mount them in a regular drilled hole, but the preferred method is a "D shaped" hole per the second pic. The d-shaped hole keeps the terminal from rotating even if the mounting nut is a little loose etc.

I have not been able to find a panel punch (Greenlee, etc.) for that sized hole. We can machine it but that's too much effort. Any suggestions for a punch etc.?





...
 
To avoid these ads, REGISTER NOW!

AE2

Well-known member
Joined
Nov 28, 2012
Messages
305
Location
Atchison KS
https://www.amazon.com/Fully-Loaded-Coaxial-Patch-Panel/dp/B0058U56P6

310nGY7tSeL._AC_.jpg
 
OP
P

pancho400cid

Well-known member
Joined
Sep 26, 2014
Messages
4,521
Location
Austin, TX

Nice... but that has BNC's on the back side and front side (shown in pic) so you basically join cables with bnc terminals on the ends at that panel connection point. I need to have solder-connections at the back side. It also has to fit in a 10" x 10" J-box.

What is this for?

Youre putting this in an electrical subpanel?

Yes. It's for instrument connections on an electric motor. Six connections (2 rows of three) on a metal panel in a 10" x 10" box.

UPDATE: BTW I don't mean sub-panel as in with electrical breakers etc. Just a removable metal panel in a J box. The instrument connections are the only thing in the box.

...
 
Last edited:

Zeke

Well-known member
Joined
Aug 13, 2009
Messages
17,176
Location
Long Beach CA, the sewer by the sea.
IDT that would be hard to make w/o going gull hog on machining. The male part of the punch can be flattened in a mill or even on the bench grinder (careful to not lose the temper). Then the female can be welded up and using the male to scribe the shape, grind and file the female to shape. Cool in oil. IDT it has to be all that accurate to get a good start on the knockout. The weld certainly doesn't have to run the length of the female barrel.

An hour's work.


Even better, run a bead on one side of a round hole in the box and file to shape.
 
Last edited:

dogdog

Well-known member
Joined
Nov 15, 2011
Messages
12,711
have you try some electronic supply warehouse websites like mouser or digikey. You might have a better chance finding it there for D-hole punch.
 
OP
P

pancho400cid

Well-known member
Joined
Sep 26, 2014
Messages
4,521
Location
Austin, TX
Closest size I could find, but still too large. ( and pricey )

http://www.panelpunches.com/u1d-05070477

Steve

Jeez... proud of that one! Guess that's made to punch holes by the thousands. Close, but too big as you said.

IDT that would be hard to make w/o going gull hog on machining. The male part of the punch can be flattened in a mill or even on the bench grinder (careful to not lose the temper). Then the female can be welded up and using the male to scribe the shape, grind and file the female to shape. Cool in oil. IDT it has to be all that accurate to get a good start on the knockout. The weld certainly doesn't have to run the length of the female barrel.

Actually... you might be right. I'll discuss that option with the guys that would end up doing it. Just to be clear, by "machine it" here, I meant just mill the holes in the panel (not make a punch). Milling holes in the panel is really not "that" much work either.

have you try some electronic supply warehouse websites like mouser or digikey. You might have a better chance finding it there for D-hole punch.

I've searched quite a bit, including Mouser and Digikey with no luck. I at first assumed it would be a common punch but apparently not.

Thanks guys!
 

dogdog

Well-known member
Joined
Nov 15, 2011
Messages
12,711
https://www.toolup.com/Greenlee-600...MI-dPKpsiW6gIVENbACh1JlQyjEAQYAiABEgJzXvD_BwE

that greenlee 60077 might be the one... since it is .5" account for some slacks it might fit. Also the smallest one they have ... but for some reason they changed their website that they won't allow you to view their specs unless you register , and in order to register you will have to be a supplier or distributor... sort of showing middle finger to regular users. :)

not cheap either.
 
To avoid these ads, REGISTER NOW!

Stuart in MN

Well-known member
Joined
Sep 8, 2005
Messages
23,135
Location
Minneapolis
I'm a retired EE, and remember having a punch for BNC-shaped holes in the tool cabinet in our lab at work, but that was 40 years ago so unfortunately I don't recall who made it. It may have been a Greenlee.

Doing a google search on 'd shape punch' turned up several offerings, but they weren't the right size and they were all very expensive (like $300 or more.) I guess maybe there just isn't much demand for them.
 

Innovate1

Well-known member
Joined
Jul 28, 2014
Messages
4,289
Location
Illinois near St. Louis, Missouri
How many panels are you making and what material/thickness is the panel? Just a flat panel or part of the box with bent sides? You could drill undersize and file or use a nibbler to get the corners.
 

Sevenhills1952

Well-known member
Joined
Aug 30, 2018
Messages
1,750
Location
Virginia
How often will you be plugging the BNC connectors in & out? If it's drilled to .382 and you use a internal tooth lockwasher with glyptal (nail polish works) and it's tight it won't turn.

Sent from my SM-S320VL using Tapatalk
 
OP
P

pancho400cid

Well-known member
Joined
Sep 26, 2014
Messages
4,521
Location
Austin, TX
Hey guys -

Thanks for all the input. In answer to some of the questions -

we are making one panel, mild carbon steel, 14 gage (.078") thick, with six holes as described.

The terminals are made by Amphenol which is a huge company that makes an enormous amount of electrical connectors, etc. I inquired about a source for the punch but getting info is a bit like talking to the Borg so far....

A plain drilled hole would work, but it needs to be as robust as can be reasonably achieved. One warranty call would pay for a hundred machined panels.

At this point I'll probably send a drawing out to the shop and get it machined. They might grumble, but it's not a big deal. We get punchings laser cut by the literal thousands, but I don't think they'd do it for a one-off part.

Thanks again!


...
 
OP
P

pancho400cid

Well-known member
Joined
Sep 26, 2014
Messages
4,521
Location
Austin, TX
Easy solution is to switch to flange mount

Good idea. Not 100% sure the flange mounted ones are electrically isolated from the panel but I did consider it (could use an insulated panel), but we landed on a solution, as below.

Deltron 911-0060

Sir.... your Google Foo is most powerful. I poked around on Allied's site quite a bit but did not find that.

That Deltron 911-1600 is correct. It's a punch for a punch press, not a drive screw as I would have liked, but I inquired anyway.

Now the bad news... It's no longer in stock from Allied. I contacted Deltron in England. they sold the entire line of punch tooling several years ago to a group called Manuform.... who now seems out of business. My emails to them bounced.

I got the go-ahead from our shop to machine or waterjet cut (their choice) the holes so... on to the next PITA.

Thanks much guys!

...
 
Last edited:
To avoid these ads, REGISTER NOW!
Top Bottom