Zobo twist center drill bit is junk

amt

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Jul 16, 2013
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Just got some Zobo forstner bits.  The forstner part seems quite nice.  The center point twist drill bit?  Total crap.  I replaced the center point with the twist drill bit, and on first attempt, the bit bent like al-dente spaghetti.  Granted this was a very hard wood (Ipe), but I have drilled in to this wood quite a lot, with even smaller bits, and never broke or bent a bit.  It's like this bit was made from aluminum (actually that's being too nice).  Anyone had a similar experience?
 

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Hi!

Pretty interesting actually!

I would have thought these drill bits are normally hardened to a degree were they would rather snap than bend. And maybe that's the answer: manufacturing error - no or wrong heat treatment?

I'd say contact Festool and I'm sure they will make this right.

And just for the record, I have no trouble with my Zobos and center drill bits.

Can you maybe tell us how that happened? Drill press? Hand held drill? Must have left quite a mess on the work piece? Did it happen while it was already completely sunk into the wood? Maybe unknowingly hit the baseplate of the drill press i.e.?

Edit: took a closer look on the picture, forget my question about the base plate as the tip of the drill bit seems to be intact and in too good shape for that.

Kind regards,
Oliver
 
It was hand drill.  As soon as I applied a slight amount of downward pressure, the bit collapsed.  I agree on expecting a bit to snap instead of bending like this.  I started this hole with the center point, drilled about 1/4" in, and then I switched the the twist drill to see how it worked.  I did not get even 1/8" in the pilot hole before it bent.
 
I've never put the drill bit into the zobo, I've pre drilled and used the solid center point to guide the zobo.  Is there even a way the zobo can clamp onto that bit to keep it turning rather than stalling in the wood? 
 
RKA said:
Is there even a way the zobo can clamp onto that bit to keep it turning rather than stalling in the wood?
Its shank is tapered and sits in very tight.
 
Hi!

[member=21641]amt[/member] I understand. Given the measurements, the "zobo head" was still far away from the work piece when you used the drill bit to guide it.

Raj ( [member=21249]RKA[/member] ) brings up another great point to be taken into consideration:

The center pin and drill bits hold through friction (tapered). It is possible that the drill bit got stuck, the actual zobo drill bit still spinning, creating heat through friction and leading to a messed up heat treatment/ tempering and the drill bit bends. But I would expect at least some visible discoloration on the drill bit if that was what happened.

That said, I have not noticed this behavior on my zobo drill bits as of yet.

Kind regards,
Oliver
 
DUDE !  That sucks !    But what really sucks is that in the U.S......the twist drill bit is not sold separately.    I broke the ZOBO twist drill bit and had to buy a whole bit kit for one freaking twist bit.    Now it scares the crap out of me every time I use a ZOBO bit with the twist bit. If it breaks.....guess what.....gotta buy a whole new bit set.    STUPID !!!

And don't do what I did....I went on eBay and bought a pack of 2mm or 2.5mm bits, I can't remember which size......but I bought a pack of twist bits hoping to skip buying a kit from Festool.....but NO.....the twist bit is tapered.......so the bits I bought off eBay wouldn't work.

Festool U.S.A should sell just the twist bit as a consumable.

Eric
 
erock said:
I went on eBay and bought a pack of 2mm or 2.5mm bits, I can't remember which size......but I bought a pack of twist bits hoping to skip buying a kit from Festool.....but NO.....the twist bit is tapered.......so the bits I bought off eBay wouldn't work.
A quick treatment with an angle grinder in a vice should fix that.

Festool U.S.A should sell just the twist bit as a consumable.
Every part of sets should be available as a spare.
 
amt said:
Just got some Zobo forstner bits.  The forstner part seems quite nice.  The center point twist drill bit?  Total crap.  I replaced the center point with the twist drill bit, and on first attempt, the bit bent like al-dente spaghetti.  Granted this was a very hard wood (Ipe), but I have drilled in to this wood quite a lot, with even smaller bits, and never broke or bent a bit.  It's like this bit was made from aluminum (actually that's being too nice).  Anyone had a similar experience?

After seeing your picture, I have decided I need to order a backup set:
https://www.amazon.com/gp/product/B...fl_title_81?ie=UTF8&psc=1&smid=A2F8KAB7F15GZF
 
[member=21249]RKA[/member],

That's the problem I have....$27 for a set of bits and we only need one of the bits.  I would rather spend $27 on a 5 pack of twist bits. 

I'm only asking for a pack of 5 at $27.......but it should would be fantastic if it was a pack of 10 for $27.  LOL !

The set you linked is what I needed to buy just for one twist bit......not cool.

Eric
 
erock said:
[member=21249]RKA[/member],

That's the problem I have....$27 for a set of bits and we only need one of the bits.  I would rather spend $27 on a 5 pack of twist bits. 

I'm only asking for a pack of 5 at $27.......but it should would be fantastic if it was a pack of 10 for $27.  LOL !

The set you linked is what I needed to buy just for one twist bit......not cool.

Eric

Well, everyone paid $233.00 for the first set (with the expensive Zobo bits).  I though $27.00 seemed cheap, since you need the set to use the Zobo bits.

Cliff
 
That pilot bit is clearly defective to bend this much.
However, this begs the question. Are Zobo pilot bits any different from regular ones? They need to withstand lateral forces produced by Forstner bit when drilling at an angle and not snap.
I wish they made pilots for Festool bigger, such as 6 mm in Zobo 3.
 
That pilot drill broke quite easily here as well, while drilling in the edge of some soft wood with a cordless drill on the jobsite.
I called Festool (Netherlands), and they are so nice to promise me to send me a new one, after I send the broken drill.
To be honest, I could have chosen a more stabile workplace for this 'edgy' task: such might have prevented the breaking.

Can't find spare center drills here in the Netherlands either, only the - way too expensive - set (filled with stuff I already have). The Festool employee will take a look for this as well, he said.
 
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