unibits for socket holes in a chassis

[dragonbat13]

I dont want to spend a hundred dollars for some chassis punches since I dont see myself building more than one amp a year.

Can I use a unibit. Is there a specific one I need?

[mlp-mx6]

They work great.

I got a set from Northern Tools that had every size I need, up to 1 1/4". Love those cheap imported tools! (still makes a round hole!)

[benoit]

Harbor freight has a set for 30 bucks, before you go writing off punches. From what I hear the holes are cleaner with the punches. I think someone here has the harbor freight ones.

[dartanion]

I spent about $45 on a high quality unibit that steps up from 1/4" to 1 1/4" and it cuts through Aluminum like butter. Very clean holes too.

[WholeToneMusic]

The punches leave no metal spurs, very clean cut . Does that justify the price? That's up to you.

[LeftyStrat]

I have both, but my set of punches is incomplete (I have huge stock of Russian military surplus sockets that apparently are metric), so for those missing sizes I use the unibits. I prefer the punches, they will work well even with steel and leave a very clean hole. But the unibits are fine if you have a drill press. I wouldn't recommend them for use with a hand drill.

You can find used punches on eBay for pretty cheap, unless it is that holy grail 1"x3/4" rectangular punch (perfect for IEC socket). Those always get bid up pretty high. Only price I have found them for new is $400. Ouch, I'll stick with my nibbler.

If you have a Costco in your area they sell sets of unibits pretty cheap. You'll need a set, because I don't think there is single unibit that can do noval and octal sockets, though I could be wrong.

[dartanion]

The unibit I have does both octal and noval.

I'll have to look up the part number. I got through McMaster-Carr and had it in 2 days along with a bunch of G10FR4.

[Funkalicousgroove]

I got a set of phillmore chassis punches for like $60 from ocean state electronics, they work fine.

[jimipage]

I've had good experience with Irwin forstner bits used on aluminum chasses. The drilling must be done slowly, but the holes come out very clean -- I've never had to file or grind any edges. The only down side I've experienced is that since they're primarily made for wood use, they do end up getting dulled after a while. My first set lasted a year(about a dozen amps). And at around $15 apiece I think it's a good way to go.
YMMV

[gearhead]

I just snagged two different Greenlee Step Bits off ebay. Combined, they do what I need (1/2, 3/4, and 1 1/8). Will see how they work.

[skyboltone]

I've had good experience with Irwin forstner bits used on aluminum chasses. The drilling must be done slowly, but the holes come out very clean -- I've never had to file or grind any edges. The only down side I've experienced is that since they're primarily made for wood use, they do end up getting dulled after a while. My first set lasted a year(about a dozen amps). And at around $15 apiece I think it's a good way to go.
YMMV

Well Jimi beat me to it. I've got a set of Bosche Forstners. Use an aluminum drilling/tapping compound available from McMaster Carr. You must drill a 1/16" pilot hole first because the tips of fortners are not a cutting edge so much as a centering device. I've cut aluminum that way for years. They're still going strong and make a perfect, burr free hole. I cut socket, jack and pot holes with them I've got 3/16" through 1" in 1/16" increments. I'm going to add a high quality 1 1/8" to the set.

[Tubetwang]

I got a 5 pieces punch set and nibler from Triodeelctronics.com and various Unibits at Home Depot. Worked out great punching holes in Aluminium chassis. They arenice to have if your into building amps. Money well spent.

[benoit]

I got a 5 pieces punch set and nibler from Triodeelctronics.com and various Unibits at Home Depot. Worked out great punching holes in Aluminium chassis. They arenice to have if your into building amps. Money well spent.

The triode kit says its good up to .068 aluminum. Have you tried on anything thicker?

[Tubetwang]

No i did'nt.

Don't want to push my luck...

[kec]

Unibits all the way! Punches can't do 0.10" aluminum. Plus, you can get a nice chamfer when you go slightly to the next step. Sweet!

I have the 3 Irwin pack plus a metric 5mm - 29mm.