pwrXfm, mounting question

[G-Sun]

Hi!
This is a question I've had for many projects:

Mounting the power transformer, there's often a mounting kit with a large screw.
The head of my current screw is approx. 4mm, and it sticks out on the bottom of my 1U case (gssl).
This doesn't work when putting many units in a rack does it?
How do you guys deal with the mounting-screw?

 

[fragletrollet]

I have also just mounted the toroidal tx with a big screw, but on non-rack units so it wasn`t a problem. How about countersinking the screw hole in the 19" box and use a flat screw?

 

[G-Sun]

I have also just mounted the toroidal tx with a big screw, but on non-rack units so it wasn`t a problem. How about countersinking the screw hole in the 19" box and use a flat screw?

Yes, that's probably much better.

My fist unit I made a big bump in the case-bottom, but that seems very un-pro.

 

[jwhmca]

Look up "Dimple die"

 

[G-Sun]

Look up "Dimple die"

Thanks! Learning
Do I need a strong press-machine to use a dimple die, or can I do it with a hammer?

 

[jwhmca]

Steady pressure... think bench vise.

 

[ruffrecords]

I think it was on this forum, but I seem to remember a year or so back someone posted a home brew method of doing this using a spanner and a few bits of metalwork.

Cheers

Ian

 

[G-Sun]

Steady pressure... think bench vise.

Ok. A Swivel Bench Vice should do it I guess.

Anyway, a countersink screw will do it for me I believe. Not the thickest metal to countersink in,
but, should be ok

Thanks!

 

[PRR]

Drill hole. Smack the sheetmetal with a ball-peen hammer. If you are very fussy, put a wrench socket under to define the diameter of the dent.

Or drill, socket under, then put your flathead bolt through hole and socket, washer and nut, tighten until dented.

This is all under the box so for DIY it does not have to be too pretty.

 

[PRR]

.

 

[G-Sun]

Nice

Thanks!

 

[kooma]

iirc. I found this on this forum and seems to work.

I did it by first drilling a hole to case.
then put countersink screw in.
Then use Bigger nut( ie. if you screw is M6 use something like M10 etc.)
then washer and a nut.

so  now you just screw that tight and metal bends.
but there was some tips on getting that bigger nut in the center...

 

[PRR]

It should be said that you "never" hit a hammer with a hammer.

Two hardened hammers against each other, a chip could shatter off and poke your eye out.

I think MythBusters tried this, and found it is not likely. Good hammers are pretty tough. Bad hammers are too cheezy to shatter. But it "could" happen. For the forces here, some heavy cardboard between the hammer faces might pad the impact yet move enough energy to the dimple. Eye-Protection is ALWAYS wise.