Slug removal from drilling operation in sheetmetal

[Wicsteve]

We have need to drill a 5/8 diameter hole in thousands of sheetmetal canisters. At present we're using a hole saw (with center drill) to drill the hole. The drilling process produces a slug that often drops inside of the canister and needs to be removed -- time consuming to remove. Anyone have a good idea to either insure that the slug remains with the drill bit or a different type of drill bit to use that might break the slug into chips?

 

[jshifflet]

you could use a step drill to make chips out of slug or
mount a small magnet with hole into drill to hold slug.

 

[Wicsteve]

Thanks,

Step Drill: We had discussed this approach but thought that the process might be too slow.

Enlarging the hole: If we drill a undersized hole then reamed the hole to proper size we might be able to shake the slug out through the hole. This is a two step operation.

MAGNET: The magnet approach is also promising. Keeping the small shavings from building up on the magnet is a problem. Anyone try magnatizing a drill or hole saw?

 

[weir]

This might sound a bit crazy but we solved a similar problem by drilling from the bottom up allowing swarf to fall away.It meant modifing a cheap pedistal drill with a bit of fabrication and a welder but it worked.

 

[JoeyHughJorgan]

If cannister is open ended, have ya considered hole punching ??

Otherwise, bag yourself a handful of small ring magnets (ID to clear holesaw's pilot drill), OD to clear 5/8" hole. McMaster-Carr keeps a fair assortment. As the magnet collects slugs, clear with compressed air or swap them out.

Magnetizing small blade tools ?? Unlikely to produce 'nuff Gauss (pull power).

Hope dis helps

 

[nbucska]

Can you blow in air -- to pressurize it ? <nbucska@pcperipherals.com>

 

[dvd]

This seems like a good application for laser cutting. Leave the slug hanging by not completing the cut around the hole periphery. Take a shop vacuum and pull the slug to the outside and twist it off. Trial and error should tell you how much material to leave the slug hanging by so that it won't sag into the hole. You could laser cut the slug into D-shaped pieces (still attached as before) for easier removal in the event that they fell into the cannister.

But, more importantly, if you are buying thousands of these cannisters why aren't you getting the holes put in by the manufacturer?

 

[Wicsteve]

Thanks all for some good suggestions We will try several of these.

 

[chiph]

you might take a second look at a unibit, step drill.
here's my reasoning;
1. .625 is a relatively small dia. very little time and hp. needed.
2.a majority of the swarf will be ejected out, not in the canister.
3.install a collar stop on the drill. once the material is penetrated, it will &quot;fly&quot; thru. this should stop oversizing.
4. the hole will be much rounder, closer to specs., and not trichordal. typical problems in drilling sheetmetal.
5. if you try a unibit, buy it TiN coated, the edge will last longer