What kind of place locally might carry hole punches for pots?
I am considering going to a machine shop to have them punch a bunch in a one-off thing. Couldn't be too expensive, and seems like a fast way to get the job done. I need maybe 6 holes in my plexi science project.
Hole punches and local places that might have them?
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Reeltarded
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Hole punches and local places that might have them?
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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martin manning
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Re: Hole punches and local places that might have them?
Holes for pots are small enough to drill, but best done with a step drill bit instead of a twist drill. These can be had at the local Lowes Depo.
Buy a good quality bit; Irwin is one that is commonly available and I've had good luck with them. I have one (part number 10231) that works for both 8mm and 3/8" pot bushings due to it's 1/32" increments. The down-side to a long bit is it has to penetrate the chassis further, and might foul other components.
A hand drill can be used for this, but it's better to use a drill press. I always center punch and make pilot holes, 1/8" or so, to get the center location exact. Run a vacuum as you drill to keep chips out of the amp.
Buy a good quality bit; Irwin is one that is commonly available and I've had good luck with them. I have one (part number 10231) that works for both 8mm and 3/8" pot bushings due to it's 1/32" increments. The down-side to a long bit is it has to penetrate the chassis further, and might foul other components.
A hand drill can be used for this, but it's better to use a drill press. I always center punch and make pilot holes, 1/8" or so, to get the center location exact. Run a vacuum as you drill to keep chips out of the amp.
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Reeltarded
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Re: Hole punches and local places that might have them?
Aha! I see. Thanks. I hate drilling metal! Off to look @ Lowe's!
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Re: Hole punches and local places that might have them?
I have bought Irwin and maybe other name brand step bits (uni-bits) on eBay for well under half the price of the Low Despot. If you are patient, you can get a small one -- up to about 7/8", maybe 1", and a big one -- up to 1 3/8" and you are pretty well set. I wouldn't buy the brand X bits as I don't believe they will last very long.
There is something I don't like about step bits. The hole is the shape of the bit, meaning it is slightly larger on the outside than the inside. If you drill soft metal with it, there can be a little lip inside that will take a little work to deburr. If you can drill in a place that is accessible to the bit from both sides, you can use the bit to deburr and then you are home free. If you are drilling pots, jacks, etc., in the vertical part of the chassis, there is rarely enough room to get to it from the inside. If you place your tube socket holes too close to the fold, you also can't get to it from the inside.
What I like about the step bit is that it makes a very round hole, just the right size, very quickly.
I use a 7/32" round chain saw file (don't ask, chain saw is long gone) to deburr the holes. You've got to be careful about not removing more material than is necessary.
Good deals, IMO:
http://www.ebay.com/itm/Irwin-Unibit-3T ... 3f123a0149
http://www.ebay.com/itm/IRWIN-10234-UNI ... 3a6e34be09
http://www.ebay.com/itm/CRAFTSMAN-TITAN ... 3370918399
http://www.ebay.com/itm/NEW-CRAFTSMAN-2 ... 33709c46a2
There is something I don't like about step bits. The hole is the shape of the bit, meaning it is slightly larger on the outside than the inside. If you drill soft metal with it, there can be a little lip inside that will take a little work to deburr. If you can drill in a place that is accessible to the bit from both sides, you can use the bit to deburr and then you are home free. If you are drilling pots, jacks, etc., in the vertical part of the chassis, there is rarely enough room to get to it from the inside. If you place your tube socket holes too close to the fold, you also can't get to it from the inside.
What I like about the step bit is that it makes a very round hole, just the right size, very quickly.
I use a 7/32" round chain saw file (don't ask, chain saw is long gone) to deburr the holes. You've got to be careful about not removing more material than is necessary.
Good deals, IMO:
http://www.ebay.com/itm/Irwin-Unibit-3T ... 3f123a0149
http://www.ebay.com/itm/IRWIN-10234-UNI ... 3a6e34be09
http://www.ebay.com/itm/CRAFTSMAN-TITAN ... 3370918399
http://www.ebay.com/itm/NEW-CRAFTSMAN-2 ... 33709c46a2
Re: Hole punches and local places that might have them?
All good points previously made. I'll add that I tape off both sides of a blank chassis with blue painter's tape and then secure my printed drilling template showing hole locations over that. When making cuts with a hole saw or Unibit, sometimes you can get metal peelings that will rotate with the bit which can create a hazy circle of scratches on unprotected metal. If you are trying to keep your chassis surfaces clean and neat, nothing like a nice hazy ring of scratches to wreck that. I use the fat 2 or 3" width peelable painters tape to protect my work.