c/cnc-operators

3

victor220•17h ago

The DRO on my 1994 Fadal just gave up mid-cycle yesterday

I was running a batch of 50 aluminum brackets when the display started flickering numbers like a slot machine then went black. Lost the entire program offset table because the memory battery is probably dead. Has anyone swapped one of those on an old Fadal without frying the board?

7

gracewebb•20h ago

Switched from coolant mist to flood coolant on my old Haas

Used to run mist for years because it was cheaper and less mess. Finally switched to flood after a job in Detroit where the mist couldn't keep up with heat on a 4140 steel part. Anyone else find flood makes a big difference on harder materials?

21

josephbutler•2d ago

TIL about coolant flow rates the hard way on a Haas VF-2

Visited a shop in Akron last Tuesday to look at a used machine they had for sale. The owner showed me a Haas VF-2 that had a weird chatter mark on every part for the last 3 months. He'd swapped tools, changed feeds, even had a service tech out. Turns out the coolant nozzle was partially clogged and only pushing 1.2 gallons per minute instead of the 3.5 it should. After a quick clean out and a new nozzle tip the chatter was gone. Has anyone else spent weeks chasing a problem that ended up being something so simple?

17

max_ross•2d ago

Rant: Spent 6 hours chasing a Z-axis drift that was just a loose setscrew

Ran a 40-tool production job last Tuesday and noticed my Z heights were shifting by 0.002" every 20 parts. After tearing down the spindle and checking the ball screw for 4 hours, I finally found a tiny 6mm setscrew on the coupling was barely finger tight. Has anyone else wasted a whole shift on something this stupid?

11

morgan.logan•2d ago

Spindle bearing just let go on a Friday afternoon...

Was running a 3/8 endmill in 6061 aluminum, pushing maybe 60% spindle load, and the machine started making this low growl I'd never heard before. By the time I hit the feed hold, the spindle was already vibrating bad enough to leave chatter marks on the part. Shut it down, pulled the belt cover, and found grease leaking out of the bearing housing. Had to call the boss at 4:30 on a Friday to tell him we're dead in the water until the service guy can get here Monday. Anyone else had a spindle fail like that with no warning?

23

thomas.parker•2d ago

The lost art of proper tool offsetting on older machines

I've been training a couple new guys at the shop in Cleveland and noticed they all try to set tool offsets on our old Haas VF-3 like it's a modern machine. They keep using the probe the same way they would on a new model and end up crashing into vises. On these older controllers you need to do a manual reference return first or the coordinates get scrambled. Has anyone else run into this issue with newer operators trying to skip the basics?

3

keith_rodriguez•3d ago

That one week where everything just lined up perfectly

Last month I had a Tuesday where I set up a new job on the Haas mill and the first part came out within .001 of print. No tweaking, no re-cutting, just hit the button and it was golden. Then on Thursday I ran a 50 piece order with zero scrap, which never happens for me. Tool change times were under 10 seconds and I was home by 3 pm each day. Has anyone else had a stretch where the machines just cooperated like that?

11

bettywood•3d ago

Old timer at work told me I was wasting time with constant tool offsets

He said just measure once and run if the part is within a thou, and after trying it for 2 weeks I cut 15 minutes off every setup, has anyone else found that over-checking kills your productivity?

10

phoenix_thompson4•3d ago

Stayed with manual tool changes instead of switching to automatic

Tbh everyone in my shop pushed me to get a CNC with automatic tool changers. They said it would cut cycle times by half and make me way more productive. But I went with a manual setup because I run a lot of short custom batches where I'm swapping tools between every job anyway. After 8 months I'm tracking about 12 minutes lost per setup versus the auto guys but I save 20 bucks a month on maintenance costs. Plus I feel like I have more control over tool wear since I'm inspecting each one by hand. Has anyone else stuck with manual for production work and felt like it was the right call?

7

kelly385•5d ago

The day I swapped my HSS end mills for carbide on a stainless job

Last month I was struggling with a 304 stainless part at the shop near Marietta, burning through HSS tools every 20 minutes. A buddy told me to try carbide inserts instead, and I figured why not for $45 a piece. The difference was night and day - same feed rate but the carbide ran 3 full hours without a chip or chatter. Has anyone else found a material where switching tooling just clicked?

21

thompson.nathan•5d ago

The chip load calculator is useless if you ignore tool deflection

I keep seeing guys here running feeds and speeds straight from a chart without accounting for how much the tool is bending, especially on deep slots. Last week a buddy snapped a 1/2" endmill taking a full axial depth on a hardened steel job because he didn't factor in the stickout past the holder. Has anyone else found a good rule of thumb for adjusting based on tool length?

31

martin.felix•5d ago

Overheard a guy at Fastenal saying he runs his coolant at 12% concentration instead of 8%

I always just went with whatever the machine manual said for my Haas VF-2, like 8% coolant mix. This guy was saying he bumps it to 12% on his Okuma and his tool life went up by like 30% on 6061 aluminum. Idk if that's true for every setup or if he was just bragging, but it made me want to try it on my next run of brackets. Has anyone else messed with coolant ratios and seen real improvement?

5

karen_west59•6d ago

Debate: tool touch off with paper vs. feeler gauges

I used to always touch off tools with a single sheet of paper. Quick and easy, never had issues for years. Then a guy at a shop in Phoenix told me paper compresses unevenly and messes with your Z zero on tight tolerance work. Switched to a 0.002 feeler gauge about six months ago. Who here sticks with the old paper method and who has gone to feeler gauges, and why?

22

robin_henderson81•7d ago

Appreciation post: That one old timer who told me to check my coolant flow before blaming the tool

Had a run of bad surface finishes on some aluminum parts last spring. Kept swapping end mills and adjusting feeds. Finally a retired machinist from the next shift walked over and asked if I checked my coolant pressure. I laughed it off but he was right, my pump was running low and the flow was all uneven. Changed the coolant lines and dialed in the pressure and my finishes came back clean in about 20 minutes. Has anyone else had a suggestion from a co-worker that seemed too simple but totally saved your day?

8

the_karen•7d ago

That time a job in Portland made me rethink my tool cart setup

I was running a 3-axis Haas at a shop in Portland last spring, and the owner had us doing these tight tolerance parts for a medical client. My tool cart was a mess - just wrenches and parallels thrown in drawers with no organization. One day I grabbed what I thought was a 3/8 end mill but it was actually a 1/2 inch, and I didn't catch it until the spindle was already running. Crashed the tool holder into the vises and snapped the end mill, which cost the shop about $120 for the holder and carbide. The owner walked over and said "you gotta know where everything is before you hit start" - real quiet like. After that I spent a Saturday building a foam insert layout for every drawer, with cutouts for each tool and wrench. Has anyone else had a crash that forced you to totally redo your organization? What did you change?

0

williams.kim•8d ago

Used to swear by HSS end mills, switched to carbide and now I get it

Honestly, I ran HSS for years because I thought carbide was too expensive and brittle for my little Haas mill. Then I had a job in stainless steel, 30 parts, and I was swapping tools every 3 pieces. Buddy loaned me a single carbide end mill and I ran all 30 without a change. The cycle time drop and surface finish sold me right there. Anyone else have a tool material conversion like that?

31

keith_rodriguez•9d ago

TIL why some operators keep burning up their spindle motors on older Fadals

I noticed this guy at the shop next door kept killing spindles on his '94 Fadal 4020, swapping motors every 6 months like it was normal. When I asked about his chip load he just shrugged, turns out he was running full depth of cut with a 1/2 inch endmill at 10,000 rpm in 6061 aluminum without adjusting feed rate. Has anyone else seen older machines get blamed when it's really just pushing the tool too hard?

18

derekjenkins•12d ago

Hit 10,000 hours of run time on my Haas VF-2 last Tuesday

The counter rolled over at 3pm while I was cutting a batch of 6061 brackets. Never thought a machine would outlast my last two trucks combined. Anybody else keep an eye on their spindle hours?

19

the_parker•12d ago

Why nobody talks about how tool offsets can wreck your whole shift

I was running a Haas VF-2 last Tuesday in Somerville and my first part of the day came out 0.015 oversize. Turns out the night guy had bumped the Z offset and never said anything. Do you retram everything when you show up or just trust the last operator's numbers?

2

dylanmurray•12d ago

Old timer at the shop told me to stop using coolant on aluminum and now I get way better finishes

I always ran coolant on everything even aluminum cause I figured it was safer. Then this guy Mike with 30 years experience walks by my machine and says I'm making chips stick to the tool. He told me to run it dry with a mist of air instead and I thought he was crazy. Tried it on a 6061 part yesterday with a 2 inch face mill and the surface came out mirror smooth compared to before. Any other tips for dry machining specific materials?

10

the_tessa•12d ago

That old timer who taught me about tool wear

Guy named Frank at a shop in Dayton showed me how to read tool wear by sound alone. Said 'the machine tells you everything if you shut up and listen.' He caught a bad insert on a roughing pass just by the pitch change. Anyone else have a mentor who taught them something weird like that?

28

rileyp49•13d ago

Debate: Tool offsets set by feel vs measured - which actually saves more time?

I've been running a Haas VF-2 for about 3 years now. First year I set all my offsets using an edge finder and paper method, take like 2 minutes per tool. Then my old lead hand showed me how to do it by feel and sound, cutting air then skimming the part. Got it down to maybe 30 seconds per tool. So my question to the group is, is the time saved worth the risk of crashing if you're off by a few thou? I've had maybe 3 close calls in 2 years doing it by feel, never actually crashed though. Has anyone else tried both ways and landed on one method over the other?

20

bettywood•13d ago

Blew $300 on a "premium" end mill set that couldn't cut butter

I saw this fancy coated carbide set online with all these rave reviews, figured I'd treat myself. 10 pieces for $300 seemed like a deal compared to name brand stuff. First job with them on some 6061 aluminum and the finish looked like garbage after 20 parts. Checked runout and they were all over the place, like .002 to .005 out. Emailed the seller and they said "normal tolerance for economy tools." Economy my ass, that's scrap. Lost a whole weekend fighting with setup and redoing parts. Has anyone else gotten burned by those flashy import tool sets?

4

willow114•14d ago

Spent $90 on a cheap digital caliper from Amazon and it drifted by .005" after 3 days

Thought I was being smart saving money over a Mitutoyo. Checked it against a gage block on day one and it was fine. By day three I was chasing an interference fit that should have been fine. Has anyone else had a bad experience with cheap measuring tools eating up their time?

24

keith_rodriguez•15d ago

Caught my tool offset being 0.015 off on a 10 part run

I noticed a guy down the hall kept getting scrapped parts from his face mill, turned out he was zeroing off the wrong surface on his probe routine. I showed him how I use a 1-2-3 block to set my Z every time, and his last batch came out clean. Anyone else run into people skipping basic setup steps like that?