Special drill bit for tin case?

[BlizzofOZ]

Is there a special drill bit that drill holes in a CMoy tin case?

Looking for that let drill without scratching and/or bending the pliable case.

Anybody have suggestions?

Thanks!!!

 

[tomb]

Couple of things -
1. A paper hole punch does wonders for near 1/4" holes in a mint tin. You may have to auger them out slightly, but as you've noticed - that's the issue.
2. Using a single drill bit the same size as your desired hole will almost always result in ripped metal. This happens on much thicker, quality cases, too. A step drill bit is standard equipment for many DIYer's. A step drill bit lets you enlarge the hole gradually, and the stress on the hole edge is much reduced. You can still do this manually, by starting small and changing out to progressively larger bits until the hole is finished - a PITA, but it can be done.

Lastly, and this is difficult with a Mint Tin - you should have a block of wood backing up the metal tin as you drill it. If you're lucky, all you need do is hold it tightly on the corner of a 2x4. There are other methods, but the important point is to make sure the tin is supported on the back side from your drill bit.

 

[colonelkernel8]

A Dremel.

 

[BlizzofOZ]

tomb,
Yeah, I messed with a test tin... I found that I could manually step drill bits to get larger and larger holes. The tin bent a bit, but I also thought that using a block of wood could be used to support.

Colonel,
I have a Dremel... what bit(s) do you use?

 

[tomb]

A Dremel will rip through a Mint Tin like paper, IMHO.

 

[Fitz]

Stepped bit in a drill press with a cross slide vise. You know you want to. You'll be the mint tin drilling king.

 

[mono]

One trick I first heard about on head-fi was to fill the tin with water and freeze it, then drill. Other than that I agree a good hole-punch is the way to go if that's the hole size you need, and you might even plan around using that sized hole, because there's no drill bit near the right size that you can use that won't rip the metal, at most you might drill a very tiny hole and then use a needle file to enlarge it, but that's tedious on thin sheet metal.


I don't see the gain in using a dremel, unless you mean using the grinding stone bit in one to make the hole bigger.

 

[soloz2]

1. make sure you use a metal bit. it will have more threads and thus take a finer bite. When you buy the bit it will tell you on the package if it is for wood/bi-meta;/metal. Bi-metal will work as well.
2. use a nail set or punch to mark your hole. that will center the hole and keep the bit from wandering before it bites.


If you have access to a drill press then use that and clamp the case in place so it does not move. If not, then still clamp the case and be careful

 

[fordgtlover]

Stepped drill and a piece of wood clamped to the inside of the tin, and of course centre punch the point to drill (an automatic centre punch is good - but you must have the wood inside first - otherwise the tin will dent and stretch)

 

[meat01]

I agree, a hole punch is great. If it is sharp enough, you can't get a better clean 1/4" hole. If you want something larger or smaller, a stepped bit works well.

 

[colonelkernel8]

A Dremel will not rip it apart...

Just use a slow setting (7,500 rpms) and then slowly work your way through it. It will give you a nice clean cut with no burrs. I have their battery operated model, so maybe it has slightly less torque than their wall A/C units.

Drill a pilot hole. (661 3/64" Drill Bit)

Grind it to size. (84922 Silicon Carbide Grinding Stone)