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OSG Flat bottom drills/Anyone used them?

NAST555

Stainless
Joined
May 23, 2008
Location
Gauteng, South Africa
So I have a customer that always specifies flat bottom holes in flanges... Truthfully I know the application and it is not needed but they INSIST on it so how I normally do it is drill 10.2mm with a carbide stub either helix or plunge out the last bit to a flat bottom (depending on what cutters I have lying around) and then tap M12. We opened up a small tool supply place and one of the agencies that supplies to us are the agents for OSG over here.

I flipped through their promotional brochure and found these EXOCARB ADF Drills - OSG

This way if I can just drill with it I can remove the flat bottom operation. Even if it is not perfectly flat it does not matter, it just needs to look flat. Anyone used these? Do they work as well as normal drills? The material in question is generally structural steel W302 normally. What are the advantages over a slot drill (normal centre cutting 2 flute endmill)? I generally dont like plunging with a slot drill because the material is sometimes a bit bent and not always have the most rigid fixturing because of shapes of the parts but have never had one move from normal drilling/tapping.

Normally about 1000 holes on a run of parts and not deeper than 2XD
 
I have some limited use with these types of drills. I have used Nachi flat bottom drills on some cast aluminum parts. They are more expensive than regular drills but the advantage is you can drill off center or on an angled surface without the need to spot the hole.
 
They are expensive. If you have a lot of holes though, I would go for it. They are good drills. Had a 6mm flat drill last hundreds of holes in 304 stainless...
 
Thanks for the replies guys!

Well currently on their promo here they are about R1000 cheaper on the 10.2mm I'm looking at!! That's roughly 85USD so I'm thinking I might get two of them and see how they go. Normal list price is about R2500 so with my discount and the promotion I'll get 2 for the price of one roughly.
 
On a side note, either we are getting ripped off here properly or the promotion is on worldwide, I see on the site I linked to the price is roughly what the promotion price is over here.
 
Go with the Nachi... they are amazing. Running one right now in 4140 PH 4800 RPM and 11ipm on my lathe and thats Conservative. Just dont try and slot or any kind of side move with them as they are not designed to do so! But for just a flat bottom hole.. Cant beat them!
 
I like OMG, so have to think they will be at the least, pretty good.

That said, one of my very first CNC lathes jobs was a .787 bore 2-1/2" deep flat bottom in SS.
Quantity was several thousand pieces per run. I found a way to get it done drilling, followed by endmill then bored...worked, but slow. I really wanted the job and knew their was a better way, so priced accordingly and got the job.
Found OTM Stinger indexable drills, Kyrocera took them over not long ago...have to say they drilled slow on the feed but high rpm kept the time down, use flood coolant only, cut easy and nice finish. Reduced my cycle time drastically.
 
I use the Nachi version and they are a great tool( I think Nachi was the first to come out with them). I use them for counterbored holes and for angled cam pin holes for mold slides. they hold up well even in tool steel.
 
Thanks guys,
Well... Nachi... Non existent here. OSG has been around here since I can remember but have expanded their agency to, luckily, a company that our little new business is a re-seller for.

Kyocera is around but pretty limited, have met someone who got a bit burnt by tooling up a new VMC with kyocera because the machine tool re-seller was also an agent for Kyocera. The reason he got burnt was because he could have rather gone with a tooling package from pretty much anyone else at a decent discount because of the full tool up. His kyocera insert mills had ridiculous pricing on inserts because of the lack of demand so he pretty much started replacing them one by one.
 
Right guys report back time,
The job was finished before the drills arrived last time around but just got the same parts in now. Tried it out this morning and I am pissed off with myself that I have not tried it before!
Got the OSG one's and they work like a charm, I am probably babying it a bit but it is working well. 60M/min and 0.1mm/rev and a small dwell at the bottom of the hole. Great finish inside the hole, in a ER25 collet with flood.
 








 
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