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Care and handling of cutting tools/

CarbideBob

Diamond
Joined
Jan 14, 2007
Location
Flushing/Flint, Michigan
So I get this from a customer of a customer.
This a CBN tip VDB-125 (not a cheap tool).
This is so bad. Terrible Oh-shit, WTF bad.
We go through a lot of effort to make sure no tools in process or packaging ever, ever touch each other.
Several visual inspections along the way also.
We are freaked. No idea how this part (and more than one are bad) can get through our system.
So it turns out the commodity place is taking them out of the package and placing them into this vending bin.
OMG.

Just because these things cut very hard steel at huge pressures they are fragile.
They do not like to touch each other ever.
The last time I had a problem like this was a big shop with a milling cutter that held 40 inserts.
They would unload the cutter, put the inserts in a basket, wash them, and put up the unused corner. :eek:

If you are indexing inserts in a milling cutter please do not pile them or let them touch each other.
Even just dumping them out of the box or tray be careful.
It only takes a tiny hit or contact to ruin a cutting edge.
We work hard to put that nice edge on. Please treat it with respect for the time put in.
Bob
 

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Glad that you found the culprit. Probably pulling your hair out trying to figure out WTF was going on until you found that out, eh?

I wish the guys selling used endmills, reamers, files and taps would figure this out, too. Can't count the times I've seen them in drawers bouncing off of each other.
 
Got these two parting blades yesterday from Penn Tool. The individual blades are in plastic pouches .010 to a side.
The usual plastic bag is .0035. The brown pouch is printed with "Sealed Air Product Care".
The pouches have folded ends so they are reusable. They do it right.

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Problem is what can fit in the vend bin.
Will not fit a insert tray of 5.
Bags above an option. This costs to single pack.
Another is to seal peel the tips. Extra costs and pain for easy use.
Here the problem is the vending device. So one per tray would be good but you run out of trays in it real fast.
When we designed the first candy bar type tool vending machines a big concern was the 10 box of $100 each CBN tools that would be dispensed.
Even in the insert box dropping this 4 feet seemed harmful and scary. So we added an elevator bin to go to each shelf. This a big added cost to the dispenser.
We were the first to make such a tool vending gizmo. A project that came from a request from Buick. First ask was a Bott cabinet with the drawers controlled.
Perhaps we over engineering it but it came from our experience of how easy it is to chip or make a good cutting tool bad.

Cutting tools eat each other for lunch with if the get friendly with another.
Not so much in HSS. Carbide, CBN, PCD very different.

I have people that make parts.
One of the first things coming is to take two SPG-422 or other and very, very lightly tap them against each other.
Now put them under the 400X video scope.

The above pics. The top left chip I would see as a manufacturing defect and I could see that as my bad and to diving into the why.
The big guy is the what the puck. The second on the top also as I think that there is no way this chip is out of our processing.

End deal is that the customer needs good tools to run with. He/she has to make parts and be able to trust the cutting tools.
Everything else is an excuse.

I take this all so very seriously. Be it mishandling later or a screw up on my end.
Bob
 
I like it when a package arrives with my inserts. Buy 2 or 3 and they ship them in the manufacturer plastic case for 10 inserts.
 
What happened to dipping the cutting end in rubber that hardens on the tip.
That's not rocket science. I've bought router bits that were dipped a long time ago.
 
A place I worked at years ago decided one day to go through everyone's tool chest and collect all of the companies loose inserts. Most of them had one or two edges that were worn some were new. All shapes, sizes, and types. Rather than putting them in insert boxes as they collected them, dumped them in a box. Probably close to thousand inserts when it was all done. One of the machinists used a lot of VNMG's with a no. 1 nose radius. They made him pick from the box. Nearly everyone picked had a damage edge when put under a magnifier. Plus, you had no idea what grade it was. They ran a lot of high nickel alloys in the shop along with 41xx materials. After a while, management told them to scrap them wasn't worth their time to go through and sort out the good ones for the bad and could not afford mis-runs on the machines from those inserts. Told the shop forman not to do that again! Now, they have vending machines.
 
We used to run a part that was bored with a Kennametal insert, which had to maintain a finish below 32 Ra all the way down the ID. We started on a brand-new box of inserts one day but the finish was no better than 75-80. Everything looked fine and nobody could figure out the problem. Coincidentally, we were test driving a high-powered electronic microscope that week so I started looking at the new inserts under 100x. Lo and behold, the cutting edges were chipped but the damage was so small that it could not be seen with our normal 30x scopes. Turns out the entire box was chipped the same way. We had a dozen boxes of the same inserts and all but one box had the same damage. We tried an undamaged insert and the finish immediately dropped below 20. Kennametal said a new operator had blown the parts off with compressed air, which supposedly caused the damage. They did replace all of the bad pieces at no charge - but we would have never figured out the problem without the higher mag microscope.
 
What happened to dipping the cutting end in rubber that hardens on the tip.
That's not rocket science. I've bought router bits that were dipped a long time ago.
Yes. The seal-peel dip in the crock pot will likely be the workaround here.
More time that we will not get paid for.
You have to wait for it to heat up, put onto wax paper and wait for it to hardened plus it just plain stinks up the packaging room.

On the above I am not buying the compressed air blow off itself causing the damage.
Maybe if you did it and the parts rattled around in the wash basket.
We check edge condition at 500x.
At this magnification everything (even a brand new razor blade) has a ragged edge so the definition is what is allowed.
 
Yes. The seal-peel dip in the crock pot will likely be the workaround here.
More time that we will not get paid for.
You have to wait for it to heat up, put onto wax paper and wait for it to hardened plus it just plain stinks up the packaging room.

On the above I am not buying the compressed air blow off itself causing the damage.
Maybe if you did it and the parts rattled around in the wash basket.
We check edge condition at 500x.
At this magnification everything (even a brand new razor blade) has a ragged edge so the definition is what is allowed.
Yes, they said the compressed air had blown the parts around in whatever container was used. We were glad they replaced the inserts so we could eventually finish the job.
 
We check edge condition at 500x.
At this magnification everything (even a brand new razor blade) has a ragged edge so the definition is what is allowed.
What are you using to get to 500x?

You could probably stuff those inserts into a piece of vinyl or silicone tubing instead of going the route of seal wax.
 
We build our own video inspection systems.
Oh my, the "Chinese finger trap" type stuff could be a great, easy and low cost thing here.
Thanks for the idea.

How is the depth of field/depth of focus at 500x on your video scope? It's vanishingly small on my optical microscope at 500x.
 
How is the depth of field/depth of focus at 500x on your video scope? It's vanishingly small on my optical microscope at 500x.
An optical stop/pin hole placed at the back focal length of the front lens helps here some.
This is know as a semi-telecentric system.
By doing so you reduce the light let in to only the close to parallel light rays.
Theoretically with an infinite small pin hole and a perfect lens you get a infinity deep depth of field. This of course impossible.
This improves depth of field but you have to pour a lot more light into the system since you throw a most of it away.
Standard microscopes will not have this.
Optical compactors will normally have something such fixed in the lens assembly and a adjustable stop on the light source to do some of the same.
Maybe think shadows. The sun is far away and sort of a point source with limited angle. It makes nice sharp shadows on a bright day. Not so much if clouds (diffuse).
Your light bulb in the living room sort of makes shadows in you stand in front but they are not so sharp and defined. Ray angles.

At this mag diffraction is also a problem to be solved. That is why you see those green filters on some optical compartaors.
 
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Oil only used on the met scope at 1000 plus.
The optics are custom so 50x and 10x do not apply.
This gets complicated fast.
While one can do your own ray tracing in any CAD. I find Zemax and Olso handy. Hear good things about 3DOptix but have never played with it.
 
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My microscope is an older Olympus metallurgical scope and has both green and orange filters, along with ND. It also has an interesting supplemental magnification system built in that was originally for taking photos but it seems to help with DOF issues also. And it also needs a ton of extra light when in use. I noticed that the objectives with smaller apertures have a lot better depth of field/focus - likely for similar reasons to those that you've described.
 








 
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