Fried Toolholders

[Kelly Burns]

We recently purchased a machine that even a brand new holder after a short run looks as though someone dipped it in oil and torched it on the tapered contact area for the spindle. Whats the reason for this? Is there that much of a mis-match between the tapers? Can u have spindles re-ground without having problems?

 

Thanks in advance!

[ERIC14779]

ah yes the good old Freting problem

 

could be a number of things... drawbar pull force low, tool too long, taper damaged in spindle.....

 

good news is yes you can regrind the taper in the spindle while it is on the machine... bad news is it does cost.

[Kevangel]

I not sure if regrinding spindle will fix fretting. I had heard moisture in air lines can contribute to this. Mine does it when I use a rougher and heavier cuts. I just clean spindle with paper towels and alcohol and scotch brite by hand, the toolholder. I would like to know more also.

[3R!< W3NG3R]

In my experiance cheep toolholders and/or cheep spindles do this.

[Kevangel]

quote:

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In my experiance cheep toolholders and/or cheep spindles do this.

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Do people with $$$ machines ever see this in 40 taper?? Mazaks, Okumas, Mori Seki, etc. Or only cheaper lighter machines ??

[billystein]

i might have to go with cheap spindle also. i never saw this until i started using fadals. i have seen them corrode after half a day. i noticed it is much worse when roughing.

[billystein]

to clean the spindle taper, take a tool holder and remove the keys. double back tape 3 strips of emery cloth evenly around the taper. push it up into the turning spindle. i have only used for removing nicks and dings.

[Kelly Burns]

quote:

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I had heard moisture in air lines can contribute to this

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This was the initial thought. 1999 Haas VF9 bought used, 40 taper; Yes it does seem to be worse when roughing. Just used an 1.5 dia Iscar plunger for about 12 hours on a plate and the holder just looks scorched where the taper is, have to give it the ol tool release tap to get the tool out of the spindle.

[iowajim62]

You could check contact in the taper with Prussian Fitting Blue. New Holder add blue, put in spindle and take back out, inspect contact area, you can tell alot doing this.

Other thought is to run spindle with no tool and see if it heats up real bad, if it does get hot then I would say the bearings are going out.

HTH

[Goldorak]

quote:

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Do people with $$$ machines ever see this in 40 taper?? Mazaks, Okumas, Mori Seki, etc. Or only cheaper lighter machines ??

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we have 5 okumas 1 cat 50 and 4 cat40

 

2 of them have make a full spin on hour meter

 

and not a single problem with taper

we only change 1 spindle cartrige on our cadet

 

to Kelly Burns

 

check your coolant concentration

most rust or other problems came from contamined coolant!!

[Guest]

quote:

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Do people with $$$ machines ever see this in 40 taper?? Mazaks, Okumas, Mori Seki, etc. Or only cheaper lighter machines ??

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At Kevlin none of our Moris EVER did this, and they would run at MAX RPM. 3-40's and a 50 taper.

 

The fadals, well we couldn't run those at max RMPS or after a few days it was time to change the spindle bearing again. So I stayed away from the 10k and only ran at 8k.

 

One guys refused to believe it, so he cranked everything up to 10k, well the next week we had the guys in ....again,,, replacing the spindle bearings.

 

I have also seen this problem on the HAAS machines I ran in the past. We had a problem with moisture in the air lines and after a good long rough, you'd see this or the holder would get stuck from the moisture dissipating and you'd have to "tap" with a lixie hammer to get it to release.

[gcode]

quote:

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We had a problem with moisture in the air lines

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If you run Haas, its worth the time and expense

to install an air dyer on your compressed air system. An air filter on each machine is a good idea too. Dirty wet compressed air will screw a Haas up real quick.

[Ocean Lacky™]

quote:

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Do people with $$$ machines ever see this in 40 taper?? Mazaks, Okumas, Mori Seki, etc. Or only cheaper lighter machines ??

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YES!!

 

Two Mazaks here and they both do it. I think it's a moisture problem. Neither of these machines have an oil mixture with the air blast at tool change. The holder will get gunked up just sitting in the spindle all day. We also have a Takumi Sekei with the oil mix....no problems at all on that machine, even running at 12k rpm all day.

[Rob_Bish]

No Problem on the Yasda here, Daishowa face and taper for all the back ends on it. Used to see it on our old Kitamura H300, but only after heavy roughing.

[New Job]

NO Problem here on our YCI's, wet air, no-oil in blast, cheap tooling, etc. etc.

[Rick Henrickson The Boeing Co.]

just an fyi does your tool changer have a hard time pulling the tool out after it has ran this long?

the problem is heat in the spindle and not great spindles overall! clean the taper in the machine very well, take a brand new holder blue it up clamp it in the spindle then unclamp and take it out, this should show you what your contact area looks like. the spindle can be reground if its bad. I would look at heat problems with the spindle which is either an oiling problem or bearings going out. also have your draw bar tension checked this should be done at least every 6 months!

[gcode]

Haas VMC spindles are cooled by the coolant flowing through cavities in the headstock.

If you run a Haas at high speed with the coolant off, the spindle will get hot and tools will stick. ( and the bearings will burn up)

Its a good idea to run a hose from the coolant

line, back to the tank so you can keep the coolant

flowing if you don't need coolant on your workpiece.

If you do that, your spindle bearings might even last a whole year.

Another lesson from the school of hard knocks

[peon]

I've only had this problem with our new Haas machines. And yes, I ALWAYS run coolant. Never had a problem with the yama-seikis, okk's, okumas, and kitamuras

[Thee Cutterman]

Used to have that problem on a Feller with a BT 40 at my last place. Only time i saw any hint of it happening on My Okuma was when i used a cheap holder.