pic: A "Bit" of a problem.

[Herodotus]

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[Cuog]

Thats quite an interesting bend there, we have a much smaller bit somewhere that got messed up quite a bit(snapped then caught and bent the threads backwards) I'll have to find it and get a picture up here now for all to see the fun xD

[Gdeaver]

It may be a dewalt bit, but its most likely a very cheap import . Sometimes it's worth the money to have a good set of bits.

[Tim Delles]

Depending on the size of the bit, the pressure on the drill bit, and the quality of the drill bit, it is very easy to bend/break them.

Normally they just break right off...

[Herodotus]

Originally Posted by Gdeaver

It may be a dewalt bit, but its most likely a very cheap import . Sometimes it's worth the money to have a good set of bits.

I don't think that is the case here, and I think it may have just been a single faulty bit. This is from a Dewalt pilot-point titanium bit set. We've been using the exact same set for about a year now, and never had any problems with the bits and occasionally we were drilling through MUCH thicker material. Then recently I got my own personal set of bits so I wouldn't have to run around looking for the few bits we had left(we have a horrible habit of... misplacing things) and it is my own personal bit that broke as we didn't have the pilot-point 5/16th bit for the class to use. But up until now, we've never had a problem with this set, in fact we love them.

Also, that single bit is $7, which doesn't seem like it would be a cheap-o bit. Still though, couldn't give you a real reason why it bent, as I have no idea.

[Grant Cox]

Reminds me of the day when, while working on our arm, I broke off two bits and mangled another

[JaneYoung]

It has been my experience with damaged tools and the persons responsible that they feel very badly when it happens. A bit that is damaged can't do its job anymore and your freshman knows that. It's great that you supported him after this happened. The shop is such an important place of learning and development - both in building robots and building teams. It sounds like your team is off to a great start!

[John Gutmann]

Umm....I would guess it is titanium coated. If the bit was pure titanium the set would have be a very high price.

[Herodotus]

Originally Posted by John Gutmann

Umm....I would guess it is titanium coated. If the bit was pure titanium the set would have be a very high price.

That is highly possible. The set is labeled as "Titanium" it doesn't say if it is fully titanium or just coated. Either way, we weren't doing anything particularly tough to the bit, so it's just a bit odd that it would get such a nice little bend in it. At the end of the last piece being drilled the student was pushing a little bit hard and the bit got caught in the piece at the end, spinning the piece into the jig we had set up. But I had that happen to myself once when I was drilling basically the exact same part and the drill had been fine before.

The cutting point is still perfectly sharp though

[ebarker]

Okay so is there any chance they drilled the hole with the bit turning BACKWARDS ? I've actually seen someone do that and melted a hole in an aluminum sheet.

[Herodotus]

Originally Posted by ebarker

Okay so is there any chance they drilled the hole with the bit turning BACKWARDS ? I've actually seen someone do that and melted a hole in an aluminum sheet.

No, it was going the proper direction, that I am certain of. Really, it was probaly just a freak accident. The bit getting caught at the end, and the piece being drilled being twisted around and then back into the jig must have just been enough to bend the heated bit.

The main thing that surprised me is that it didn't just snap in half.

[Mike Harrison]

Yes, drilling backwards would do the trick, an easy mistake to make for a new guy. But then again, haven't we all bent/broken/mangled our own fair share of bits. I know i've went through at least 5-6 rivet sized drill bits myself... not titanium but still...

[ebarker]

Okay so is there any chance they drilled the hole with the bit turning BACKWARDS ? I've actually seen someone do that and melted a hole in an aluminum sheet.

[dtengineering]

Sheesh... it's not a material or manufacturing problem... it's a SUPPLY problem... you've got a DeWalt Ti5443-C, for drilling curved holes, on the left and the matching DeWalt Ti5443-S for drilling straight holes on the right. Our local vendor gets those two mixed up all the time!

Jason

[Cory]

Originally Posted by Herodotus

That is highly possible. The set is labeled as "Titanium" it doesn't say if it is fully titanium or just coated. Either way, we weren't doing anything particularly tough to the bit, so it's just a bit odd that it would get such a nice little bend in it. At the end of the last piece being drilled the student was pushing a little bit hard and the bit got caught in the piece at the end, spinning the piece into the jig we had set up. But I had that happen to myself once when I was drilling basically the exact same part and the drill had been fine before.

The cutting point is still perfectly sharp though

Yeah it's not titanium. It's called Titanium Nitride coating. Helps with lubricity. Actually doesn't work all that well in Aluminum, from everything I've read (it doesn't resist chip welding in aluminum real well, apparently).

Any drill you might commonly come across will be made out of either High Speed Steel, Cobalt, or Carbide.