Hole drills

[TubeMack]

Any comments on these? Anybody here try them?

http://www.vt4c.com/shop/program/mai..._id=8&hit_cat=


Would something from Home Depot work just as well?

[Wavebourn]

Powerful drill press and stiff fixing of chassis is needed. If to drill somewhere in the middle of the chassis the drill press have to be also big enough.

I prefer Green Lee punches.

[torrence]

What are you drilling? I used super cheap hole drills from
Harbor Freight and they did fine through 1/4" aluminum,
but I am sure they wouldn't work at all on stainless steel.

[Ty_Bower]

This is what I use:
http://www.harborfreight.com/cpi/cta...emnumber=96275

I only use these step drills in aluminum. They make a lot of chip. Be prepared for it. I haven't tried anything thicker than 1/8" aluminum, and I've never tried a steel chassis. With these things in mind, they've served me well all the way up to 1 7/32" holes for big octal sockets. I've been told that quality Greenlee chassis punches will do a better job, but I'm not willing to shell out the coin.

I'd imagine the hole drills you linked would make less mess, but make sure you buy the right sizes you need for the job. I'd like to have appropriate sizes for two kinds of octal sockets, noval sockets, transformer lead holes, power switches, and speaker binding post holes.

They really do make smooth looking holes. I've never had a problem getting them to land where I wanted them. You can use the next size step to de-burr the size you just drilled. Just lightly touch the hole with the next bigger step on the bit. Flip the chassis over and de-burr the other side too - it makes a nice smooth hole which won't nick wire insulation. Maybe the particular alloy of aluminum helps make clean holes?

[TubeMack]

I'm drilling into 5mm aluminum. I want to use what ever will give the best chance for success the first time around, as the plate is a part of a very expensive chassis and cannot be replaced easily!

I'm building a 12B4 /OD3 preamp.

[Ty_Bower]

Originally posted by TubeMack
I want to use what ever will give the best chance for success the first time around

Get some scrap 5mm aluminum plate, and practice first. Make sure that the "first time around" is the second time.

[athos56]

I use cheapo ACE hardware hole-saws on my Black and Decker drill to make holes in the Steel chassis's from Hammond. If I avoided doing what everybody seems convinced is unworkable I'd never get anything done. I don't use any lube or anything, just drill the guide hole, slap on the saw, put in some ear plugs and have at it full blast. If I need it secured I use my knee. Funny thing is, the holes are good enough and the only wear on the saw is stripped paint and minor dulling. I drilled all my holes this way in my last two projects with the same saw and its still going. Any roughness on the hole is covered up by the socket.

That being said, when I owned punches they did a much better job. But price wise, the greenlee punches are too much.

[TubeMack]

Ok, punch questions...

Would the cheap HF punches work for a single project before being useless? Future plates will come from Front Panel Express!

Would they or the Greenlee punches go through 5mm Aluminium?

[Ty_Bower]

The Harbor Fright punches will NOT go through 5mm aluminum. I managed to drive them through 3mm, but it took a 15 inch ratchet handle and a lot of swearing. The hole was serviceable, but had four obvious bite marks where the punch went through.

The other bad thing about the HF punches is that they are not sized appropriately for tube sockets. The little one is too small for anything, and the big one is too big. The second smallest might pass for noval sockets, but is a hair large. The second largest just barely fits an octal socket, but you have no room for error.

[Poindexter]

Wandering thread.

The VT4C hole saw thingies are a bust.  The problem is that the teeth aren't quite even, so one tooth ends up doing all the cutting, and gets clogged up with schwarf.  I lubed them with cutting oil; I've since heard of cutting wax, which may ameliorate this problem somewhat, but clearing that one tooth of chips will still be laborious and time consuming.  I think that maybe a carbide holesaw would be a better solution.  I use modified spade bits to do de do in .125" (~3mm) aluminum, but I don't recommend it generally; it takes considerable experience and skill, it's a dangerous cut.

I have no direct experience, but I don't think a punch, Greenlee or otherwise, is going to deal with 5mm (that's over 3/16") metal of any kind, unless it's lead.

In the best web tradion, torrence recommends 'super cheap hole drills from Harbor Freight', but neglects to link to these.  I would be interested to see; but still think a high quality carbide holesaw the mutha for ya.

Aloha,

Poinz
AudioTropic