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Hoffman Amps Forum image Author Topic: Chassis punching  (Read 6467 times)

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Offline aro

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Chassis punching
« on: January 29, 2010, 01:19:29 pm »
I want to punch some holes in a Marshall chassis and I found a kit like the one in this link. It says it's for up to 10 gauge steel. Isn't Marshall more than that? If yes, what other punches could I use? I looked online and some punches specify the gauge, some don't. It's hard to know for sure. Thanks.
« Last Edit: January 29, 2010, 01:45:06 pm by aro »

Offline tubesornothing

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Re: Chassis punching
« Reply #1 on: January 29, 2010, 02:11:05 pm »
I doubt the marshall chassis is 10 gauge steel - 10ga is **very** heavy.  That kit will probably work fine - it is a chinese knock off so will probably wear out quick.  Do a search on "unibit" and you will see lots of discussion on how to put holes into chassis.


Offline FYL

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Re: Chassis punching
« Reply #2 on: January 29, 2010, 02:17:43 pm »
10 gauge = 0.1345" = app. 3.4mm

All Marshall chassis I've seen are either 1.5 or - for Al - 2 mm thick, so these punches seem to be usable. Work slowly, use plenty of cutting oil : steel can be quite messy to work with.





Offline aro

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Re: Chassis punching
« Reply #3 on: January 29, 2010, 02:29:04 pm »
Great, thanks.

From what I read  I first need to make a pilot hole for the chassis punch. Can I use any metal drill bit for that? I don't have any tools but I have access to lots of them through my band mates, so I need to know what to ask for.

Offline tubesornothing

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Re: Chassis punching
« Reply #4 on: January 29, 2010, 02:40:32 pm »
Yes, any metal bit will work fine.  Make sure to use a center punch so the drill doesn't skate allover the place.

Offline stratavox

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Re: Chassis punching
« Reply #5 on: January 29, 2010, 02:56:00 pm »
Second the Unibit.....

Offline aro

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Re: Chassis punching
« Reply #6 on: January 29, 2010, 03:47:41 pm »
OK, I'm totally not the handyman, I'm THE non-handyman, I'm one of the best non-handyman I know. I thought that a punch would be easier to use than a unibit. How do you make a preamp hole, or FX loop holes with a unibit...? There must be more to it than just drilling a hole, especially when I think of the diameter needed for a EL34.

Offline tubesornothing

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Re: Chassis punching
« Reply #7 on: January 29, 2010, 03:52:05 pm »
You can get a unitbit that goes from 1/2" up to 1 1/2" - thats enough for all amp building holes.  Not quite as clean as a punch, but it works - and is fast.

Offline aro

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Re: Chassis punching
« Reply #8 on: January 29, 2010, 03:59:53 pm »
When I search unibit here all sorts of bits come up, including step drill bits. Do they all work for an amp? Do they work with a regular drill?
How do they work; just center punch and then drill away?

Offline FYL

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Re: Chassis punching
« Reply #9 on: January 29, 2010, 04:27:11 pm »
Unibit is an Irwin trademark for their line of step bits - excellent quality, high price.

If you're going to build a couple of amps only, a cheap step bit such as the Neiko is fine.

http://www.amazon.com/Pro-Quality-Titanium-Step-Drill-Bit/dp/B000FZ2UOY/

What kind of chassis are you planning to use? Aluminum or steel? Which gauge or thickness?

Have you access to a drill press? A handheld is barely OK if you want to work with aluminum and inadequate for steel - except if you do four passes using standard drills (pilot hole then larger then larger up to say 3/8", then the step bit).

Holes won't be clean with a step bit, you'll have to manually deburr them. Check manual deburring tools and get a number of different blades.

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dtools&field-keywords=deburring+tools



Offline aro

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Re: Chassis punching
« Reply #10 on: January 29, 2010, 04:32:48 pm »
http://www.amazon.com/Pro-Quality-Titanium-Step-Drill-Bit/dp/B000FZ2UOY/

What kind of chassis are you planning to use? Aluminum or steel? Which gauge or thickness?

Right now I want to drill a Marshall chassis. Later on, both.

Quote
Have you access to a drill press?


Kinda...but it gets complicated.

Quote
A handheld is barely OK if you want to work with aluminum and inadequate for steel - except if you do four passes using standard drills (pilot hole then larger then larger up to say 3/8", then the step bit).

And that's why I was thinking of a punch, it seems to be easier to use.

 


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