making a 5" hole in a non-removable aluminum panel (question)

[Opcom]

I'll sneak this in here, but won't let this stray off topic because the CRT and hole job is what it's all about! And it should be done tomorrow Monday because I'm off work!

The laser meeting was a real success! Never seen anything like it as technology has sure progressed since my last messing with professional visible lasers.

The hands-on was great, everything from lumia homebrew techniques to alignment of galvanometer servos! - it is still an analog technique requiring back and forth tweeking and an understanding of the basic principles. Then there was setup and a full automated laser show with at least 8 projectors that I know of. And fog, this was in a room about 60x60.

I won door prize #2, a 447nm (deep blue) OEM laser module rated 300mW CCS. It was donated by Aixiz. More cool because I never win - last time was  that brand new IC-2AT and OSCAR-Locator at a hamcom. Even more cool because Jacob was with me as a guest and he was chosen to pick tickets for the door prizes. The #1 prize was a Pangolin laser show system. Someone else won that, so I called out,"Jacob, I need that laser!" and he did it.

The module has an analog input for modulation, don't know the input bandwidth yet. 447nm = 670GHz though. I need to buy some goggles before messing with it further.

This has been a public service announcement. We now return you to the "Vicarious Hole-Punchment" Channel. Stay tuned for part two: "The Chinese Wrench".

[Opcom]

Success!

Armed with the 2" wench, the hole has been punched. Even with the leverage it was not so easy, but it is better to have taken it slow than to force it. There is a video of the wrenching but it is 226MB so it needs shrunk and posted later.

It is as if that punch was made for this CRT. Big thanks to Dennis, and to all that offered advice.

I can not use the existing shield because it is too close to the tube socket so i would like to find a more form-fitting one. I guess we will see later if magnetic fields is an issue.

[W7TFO]

Greenlee to the rescue!

I bet there was quite a 'pop' when the last cutter went through...

73DG

[K5WLF]

Very nice, Patrick. Looks like it grew there.

[Opcom]

There was no real pop, it was a soft 'tink' sound. There was also no real deformation of the panel. The panel is just under 1/8" thick. The piece that came out is a good candidate for wind chimes because it rings nicely and now has an interesting 3-D shape.

Thank you for the good comments on the job! It could not have been as tidy without the punch.

The bezel shown there will probably be the one used. It fits the standard Tektronix bezel bolts. In the old scope that was cannibalized here, those seem to be pressed into the front panel. That scope has two front panels apparently in inside one and a nice looking outer one. I am not sure how the bolts might be removed to be used in the transmitter.

[KA2QFX]

Nice job OM!

I can't wait to see that trapezoid.

[KA2DZT]

Patrick,  great job,  after everything was said and done the trusty Greenlee punch did the job.

Good thing that Dennis had one that large.

Fred

[N0WEK]

Looking good!

[W7TFO]

That was but the second documented use of that giant.  I did a speaker hole in a panel a few years ago with it.

It looked unused when I bought it, no wonder as 5" conduit is not that popular.  It was part of SK consulting engineer Dick Haskeys' estate.

Holey panel, Batman!

73DG

[The Slab Bacon]

Success!
Armed with the 2" wench, the hole has been punched. Even with the leverage it was not so easy, but it is better to have taken it slow than to force it. There is a video of the wrenching but it is 226MB so it needs shrunk and posted later.

If it jams, force it, if it breaks, it probably needed replacing anyway................  

(Murphy 1:14)

[Opcom]

speakers.. Maybe I should do a little more punching before returning that. I regret having sold the old 5" rackmount speakers. Not that they sounded that good but they worked and looked great in flat black. Paper cones with whizzers!

[Opcom]

I had a few minutes today and mounted the high voltage CRT power supply and mocked up the location for the transformer for the low voltage portion.

The CRT circuit was under discussion here:
http://amfone.net/Amforum/index.php?topic=31066.msg242335#msg242335

- But the schematic's changed a bit again. It's a little tricky balancing the voltages because of the very low current (2mA DC total) of the power supply transformer. With the voltage divider passing so little current, things like X and Y position pots and connections to the other (5400V) supply can upset the voltages.

Back to the mountings, I have to buy some 1/8" thick 3/4x3/4 aluminum angle to mount the LV transformer.

Each transformer/box weighs 5-6 lbs. It's worth mentioning that capacitor clamps with small tangs that fit over the ridge at the power supply's top are weak in that area. Tightening the bolts actually will straighten them out, 'flow' them around the steel ridge and loosen the iron.

They would be fine for a light weight capacitor, but I am not as pleased with them in this service where the object to be clamped is heavy. My worry is it breaking loose at some point and striking that costly and special CRT.

The picture shows each of the clamps has two small tangs. I would prefer to find some with a larger and continuous tang. Wider is better.

If anyone has some. At least 3 are needed. (entered in 'wanted')

[David, K3TUE]

Of course if you add a bezel you can cut it with anything...

Like a can opener?

[David, K3TUE]

Success!

Nice!

[Opcom]

A can opener, being made of steel and properly prepared, would have eventually cut the hole.

[Opcom]

The tube is in. What a slow project but it is moving.

[K5WLF]

Looking good, Patrick.

[Opcom]

Thanks!

Here are the attach points. The brass screws up front worked ok. I am not sure I like the appearance but they work well. The front of the tube was some 0.07" smaller than the hole and it rattled so I wrapped 3 turns of some thick but soft nylon tape around the edge and it fits perfectly and somewhat cushioned without binding. Later I can redo this using the correct shield and the tube will be partly supported by that. The tape came from a trailer full of military junk. I don't know where it can be had.