O/T Spindel

[Fig sign]

Hi ,brothers and sisters Mastercamers!

We changed spindel for our Deckel-Maho DMC-63v.

It was a scrap from the start and after 5 years it was all gone .

The new spindel seems to be OK !

But God knows how long it will work .

I worked on VMCs of 15-20 years of heavy duty like Mori-Seiky and Okuma without any prob with spindel and this scrap was killing me for 5 years and it`s construction looks so unimpressive that I am preparing to the worse to come soon once more !

Speaking in general it looks like quality in last 5 -7 years had fall so low that any machine tool from 15-20 years before has far more reliable spindel that any this low-cost pc-based cheap use and throw away junk they call modern VMC for reasonable price !

 

What experiance do you have fellows with modern machines ?

Do you dare to work with max speed for a long time ?

What problems do you have ?

 

Iskander teh curious

 

[ 10-19-2003, 05:36 AM: Message edited by: plasttav ]

[George_Gerhard]

Plasttav

 

just curious, what materials are you machining. Cast iron will definitely penetrate the labirynth seals, as will fiberglass.

How was your spindled cooled and lubricated.?

 

I have seen spindles cut aluminum at 6-10,000 rpm last 12 years

 

regards

George

[Fig sign]

George !

 

It was not good from the start .

When we first time tried it it made loud noise on 900 rpm !

I turned it by hand and felt it is not good !

I repaired sport bycicles once and my bearings worked 10 times better

So I told this to my boss but he was in WGAF mode charmed by the name Deckel-Maho ,German machine and all this tales from the past .

The machine and spindel is not for molds and I was making molds !

Little tools and it means a lot of rpm , 80 % of time close to max(8000)which is too litle for me anyway .

AND mostly mold steels ,hardened steel ,copper and graphite .

It was not a surprise for me when the tapers started to breake ,but I was not prepared for reamers to do the same !

And z changing every 15 min adding 0.01 mm because of overheat .

And surface smoothness .

And..

And..

So old spindel RIP .

Long leave new one !

But sealings are not enough ,there was a water coming to bearings and it can easily happen once more due to the s&*t design.

And they (bearings so weak )!

Cooling through water heat sink !

It is a cheap solution the same as my toolchanger (not an arm ,but a plate type)over the table with the chips and water falling over it .

And the Famous damn Sinumeric on Pentium S 100 with 32 ram and win95 !!!!

I only want that my boss will understand what it makes me always stand to +-0.01 mm.

 

 

Iskander teh spindel terminator

[George_Gerhard]

My full time job is as an engineer, but I sometimes also repair machines on the weekend for extra money. I retrofit old machines with newer Fanuc controls, and basic repairs. I just rebuilt a spindle on a old Mazak with an old Fanuc 7 control. They cut alot of graphite for edm electrodes, and this is what destroyed the bearings. Machines in a hazardous environment should have either an air purge at the nose of the spindle, but the air "must" be free of water, or the bearings lubricated with air oil mist. I have many years experience with high speed spindles 18-30,000 rpm and the spindles that are air oil mist lubricated last the longest. The only draw back is they need constant maintenance to make sure the proper oil to air ratio is maintained.

 

good luck

George

 

ps

I downloaded one of your tricks the one with the spheres. I have a job comming up where I must project an image onto a sphere. I have not done that yet in mastercam, but I have done it a few years ago in smartcam

[Rekd™]

Plastav, you did a break-in program on the new spindle, right? Very important.

 

On HAAS/FADAL types, spindles aren't really that reliable. Kits, Mori's etc seem a bit more sturdy.

 

I used to run a HAAS that saw 3 spindles in less than 7 days.

 

'Rekd teh Destroyer

[crazy^millman]

+1 on that Rekd warm up cycles are very important for the life. I have also seen my share of replacement spindles the biggest reason I get 2 year warranties over the standard 1 year most people dont like to but you put up the condition of a sale on it and most cave.

 

Crazy Millman

[MetalMarvels]

Definitely +1 on the break-in and warmup cycles on the Haas/Fadal types. The 3 Fadals that I have access to will grow as much as .0014 in the 1st 30-40 minutes at a warmup speed of 4500 rpm. They are pretty stable (for this class of mill - no flames please) after that - staying within +/- .0003. However, you can chase your backside if you don't warm them up first..... They will also smoke themselves if you run them full-out.

[pimij]

We have a brand new Deckel 200P 5-axis. No problems but we cut mostly alum and some steel - P20 is the hardest and some 4140. Has a high speed spindle on it and runs great.

The control is a heidenhain itnc 530 - runs of an amd k6-2 - yes a k6-2/266 - in a wierd custom unix environment. Not my favorite setup - editing files is slow as mollasses. And it won't backplot anything to do with a 4 or 5 axis move. But other than that its good.

[Elad]

One of our machines is a vertical BT50 milling machine with max speed of 6000 rpm.

It took about a week to kill the spindle!

I tought it will be ok to use the max rpm sometimes.it's not that i'm in the max speed 24 hours a day.

The parts that i had to buy to fix it are so expenssive and i couldn't find it anywhere so i just ordered them from the factory in taiwan.

 

since then, i never use max rpm.

[crazy^millman]

Yeah I found out about the duty cycle on the Fadal after being here about a month 5 hours aat Max 10,000 rpm then got to let htem cool for atleast 15 minutes but they prefer 1 hour. I was only doing a 14 hour finish cycyle. I got a new spindle in the works on the 40 x 20 right now I am at hour 52 on a finish pass for part on that machine.

 

Crazy Millman

 

[ 10-20-2003, 05:09 PM: Message edited by: Millman^Crazy ]

[Fig sign]

I never use them 2.

But if I have 8000 7850 rpm is close to max ?

 

Well ,today at work I made copper electrodes:

End mills 0.3,0.5,1,1.5and 3 mm ,balls 1,1.5,3,6 mm most of the time .

8 electrodes 5 hours machine time.

Do I have any other options except to work close to max RPM ?

 

I wrote and used warm cycles they does not help much in my case - to start 1000 rpm for 10 minutes and start strait 7000 for 5 hours ?

 

I had a look on the disassembled old spindel -

it`s design looks so weak comparing to Mory-seiky

MV-40 25 years old .

 

And cooling sucks .

 

My emphasize is that modern machines mostly weaker than old one and not built to use for such a long time.

 

Iskander teh spindel cracker

 

[ 10-20-2003, 05:10 PM: Message edited by: plasttav ]

[crazy^millman]

Well that goes hand and hand t omy commnets in another thread. The machine builders are more worried sbout getting something out the door to sell then making it better a majoity of the time.

 

Crazy Millman

[Henk]

Warming up is important, but the first break-in procedure for a new spindel is VERY IMPORTANT for the spindel life

 

We have 2 DMC V70, 18000 rpm max, 2 years old.

I program max 17500, and some times a machine runs 17500 for 10 ours.

No problems til now