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View Full Version : Tried out the Tapping head this afternoon!



Buckshot
01-26-2009, 04:49 AM
...............No it's NOT a Procunier :-) And yes, the destructions were barely in English. This was part of the milling machine accessories I'd bought during the 2 years preceding buying the mill.

Your typical bonehead here.

Why do they sometimes include directions, but that' are written like you've already used one before, if not THIS very unit? Maybe they should also add a line that says feel free to 'Intuit", or read between the lines? But no. They DO go into quite a discussion about using lube, why use lube, and what it's benefits are. Wasted on me regardless because I'm an oiler. If it moves, I oil it regularly and have the T shirts with the oily racing stripes to show for it.

These directions cover 4 models and without too much brain trauma I figure out which one is mine. It says mine will stand 1000 rpm. !!!!!!! I've never tapped at 1000 rpm before, and that's ALL they have to say about speed. So okay, in the cutaway of the unit it's all full of gears, clutches, springs, guide pins, and other doo-dads. I figure it has a reduction gear in it.

I'm making a bunch of T nuts to fit the rotary table. More then I'll ever need to use at once, but they're simple and fun to make. I need to thread 3/8-16. The T nuts are still in the shape of one long bar, so I figure out the distance between each hole for the DRO. Set it up and have a great time drilling 10 holes. Lower the knee to replace the chuck with the tapping head.

Raise the knee back up, then go have another cup off coffee and a smoke whille reading the instrucitons over again for the umpteenth time. Maybe they added something while I was busy elsewhere? It says to lower the 'Attachement' which is their word for the tapping head, so the tap lightly touches in the hole. Also they say, it is advised to give a quick upward movement on the quillfeed when reversing the tap to avoid wear on the "Attachment". Huh? Okay, I can do that.

So I start the mill and set the VFD for a spindle speed of about 1000 rpm (are you guys laughing yet?) and lower the quill. Holy Hannah on a Pogo Stick! The poor tap when ZZZZEEEEEERRROOOOOWWWW, down through the cringing hole, hit the quill stop reversed and sat there spinning in the NOW no longer 5/16" hole but the NEW 3/8" hole. That tap went through the steel like a drill bit, HA! Since there were no threads to grab onto the tap didn't back out.

Ya know, SOMETHING just isn't right here (like, no crap huh?). After much cogitation, coffee drinking and cigarette smoking I devised a plan that was mentioned NOWHERE, nor even alluded to in the instructions. I would put the mill in back gear and try again. The only thing even remotely close to suggesting it, was their comment of following the tap as it fed with the quill feed and THEN give that quick upward movement to the quill they suggest.

Reading between the lines, it seems the quill would be moving rather sedately? Otherwise it's impossible as my neural synapes simply do NOT fire fast enough to follow the tap down, and then do that quick upward quill move deal. No way brother! Smart fellow that I am, with the mill now in back gear, I tone the motor speed down by half. The spindle I can see is turning at a speed any sane person might consider as suitable for tapping.

Squirt some juice on the tap and lower the quill. I was still a bit aprehensive as to what COULD, or MIGHT yet happen. I mean, who knows, ya know :-)? After all, that 3/8" hole is STILL smoking, HA! Believe me, I was ready to drop everything and RUN!! When the tap entered the hole the tapping head went click, click, click ...........and I figured I'd busted it, but then the tap started turning and dragging itself AND the quill down with it, EUREKA! Give it another shot of juice and it's still going (I'm enraptured) then it breaks through, runs a down a bit more.

It hits the quill stop, and goes "CLICK" and stops turning. Give the quill handle a flick upwards and it does another click and the tap reverses and start backing up out of the hole, ZOUNDS! I even got so I'd reverse it halfway, clean some chips out and then complete the hole. I finished the other 8 holes without a hitch. In fact I went looking for other stuff that might need some 3/8-16 threads but was fresh out.

Now WHY in the H E double hocky sticks didn't the instructions suggest a spindle speed of X with a Y size tap in plain low carbon steel? But no, all it says is that the "Attachment" will stand 1000 rpm? It has a master clutch you're expected to adjust and they say to set it at it's lowest point and then keep adjusing it until the tap turns and feeds, then record the setting for future use. That makes sense as they couldn't cover every possible scenario, but come on. One column for common ole low carbon steel, a list of taps and then a conservative rpm suggestion, and another for maybe aluminum as 2 common examples.

Anyway, I now have it hammered but I doubt I'll ever just casually use it unless I have a bunch of holes to be tapped. Another hurdle er, .........hurdled :-)

..................Buckshot

45&30-30
01-26-2009, 05:11 AM
I know the feeling, I just purchased an 815 Logan lathe. I purchased the manual on Logans website. I think I could have bought a book on transcendental meditation and learned more about my lathe.

454PB
01-26-2009, 03:25 PM
When I was still supervising maintenance crews, most of the guys were "heavy handed" with all tools, both manual and powered. I assigned one of the more experienced guys to drill out some stripped holes that secure the covers on the inside of a hydro turbine. The stripped holes were 7/8", and he was going up to 1" in a cast iron casing of about 3" thickness. Working inside one of these turbines was not pleasant, everything is wet and slippery, the constant roar of water leakage, and nothing flat to stand on. I crawled in to see how he was progressing, and he's got a 1" drive impact wrench attached to the 1" tap and pounding away on the third of about a dozen holes that need repaired. He didn't even drill them out, just muscled that big tap into the cast. Oh well......whatever works!

Cap'n Morgan
01-26-2009, 03:26 PM
I would've loved to see the look on your face when that tap took off at 1000 rpm :shock: With sixteen threads to an inch the tap was diving with more than an inch pr second.:wink:

lathesmith
01-26-2009, 04:32 PM
Tapping @ 1,000 RPM? Now that's funny! I guess now you can thread to a shoulder @1,500!
Seriously, trying to figure out the instructions of some of these machine tools can be an excercise in frustration. Sounds like common sense prevailed, and eventually won the day.
Threading/tapping is definitely an art, and sometimes to get it good, right, and fast tests the limits of your patience (not to mention vocabulary!) Thanks for the front-line report Buckshot, we appreciate it!
lathesmith

dragonrider
01-26-2009, 11:48 PM
Things to remember when using a tapping head,
Make sure there is clearance under the piece being tapped so the tap does not contact a hard surface.
Do not tap at 1000 RPM's unless you have 100 years of experience in doing so.,
Firmly pull down on the handle so that you feel resistance, this will prevent slipping. reverse you motion to up quickly and keep resistance in order to prevent slipping. Use plenty of oil, that's right you are an oilier, that's good.
Use a speed of 250 to 300 max.

I have a procunier tapping head, never use it unless I have more that twenty five hold to tap, I simply power tap with the tap held in the quill and reverse at the appropriate moment. It is not difficult and being a guy one day you will try it. With a tapping head you can tap loose pieces easily when power tapping parts should be held securely. You may break the occasional tap at first but less as time goes on, I haven't broken a tap in years. That little bit of boasting will probably cause me to break the next tap I use[smilie=1:

Catshooter
01-27-2009, 06:27 PM
Buckshot,

I'm surprised and disapointed in you. Everyone knows that tapping at 1000 rpm is easy, you just use the 3/8x16xthree foot tap. Cake walk.

Kids these days . . .


Cat

quasi
01-27-2009, 07:24 PM
LOL, very funny. I am glad you are enjoying your new mill. Now you need a Shaper, a Die filer, a Surface Grinder ...

TAWILDCATT
01-27-2009, 09:15 PM
buckshot:this is not the right thread it should be in the joke section.when I saw 1000rpm I thought I would die lafing.Worked for 13 yrs in Ratheon in drill department.and tapped thousands of holes,6/32 8/32 1/4 /20 and 1"- 1 1/2- 2" with a 4' swing radial drill.used a procunier on small and the spindle on radial.
:coffee: [smilie=1: :mrgreen: :mrgreen:

Buckshot
01-28-2009, 03:19 AM
...............I can laugh now. :-) Catshooter, if it'd been 3' long it would have undoubtedly gone on down through the table and into the knee before I could have applied the suggested "Quick upward flick" of the quill handle!

...............Buckshot

Jetwrench
01-28-2009, 03:29 AM
I'll just bet by the time running hit your brain it was allready over, you diddn't even have time to say OH SH++!!!! Best laugh I've had all day. THANKS Jetwrench

Willbird
01-28-2009, 09:51 AM
I had a cnc tapping head at an old job, when I got it I tried it tapping some 8-32 holes....I ran the rpm up to the maximum suggested speed, it worked very well actually, but of course you got a few extra threads than the cnc program depth....it was kind of spooky because as the spindle deccel you could HEAR the 8-32 tap cutting...it's pretty weird to actually HEAR a tap that small cut :-).

Catshooter
01-28-2009, 07:33 PM
You mean:


...............I can laugh now. :-) Catshooter, if it'd been 3' long it would have undoubtedly gone on down through the table and into my knee before I could have applied the suggested "Quick upward flick" of the quill handle!

...............Buckshot

Got a good laugh outa that one Rick.

I worked a couple of years in a shop where the machinist and would train each other (I was an electrician). I went to him one saying my Bridgeport was smoking a little and to come tell me why. I had chucked up an inch and a half end mill and cranked the RPMs as high as it would go, left it running with the end mill about .003 from touching the hunk of steel I had in the vise.[smilie=1:

I though his head was comin' off. He was a fun guy to work with.


Cat