[OkumaWiz]

I've heard the P and F commands can both be used with the G4 dwell but haven't tried P ex: G4F.5 is what I typically use. X cannot be used. By doing that I can then search for P values and find the P codes since they would only be used for sync commands. Machinehop5 gave a good example of the P codes and how they work.

Remember codes and RPM's must match so don't use M41 on one side and not the other. RPM's must match exactly for either G96 or G97. They can't disagree whatsoever on what the spindle is doing. If a command is on A it better be on B with P codes or get ready for alarms.

Best regards,

[okuma1984]

https://www.youtube.com/watch?v=XXn3...ature=youtu.be

[OkumaWiz]

Now that's more like it!

[okuma1984]

that was from Tuesday when i posted the program i forgot to upload the video too. so it's only one turret. i like to be able to use both turrets eventually
not for facing LOL but for od turning/finishing or boring.

[OkumaWiz]

Facing would be under P10 and turning would be under P20 for both turrets. If you use a canned cycle, you will need to Pcode every line inside the shape definition from G81 to G80 to keep them in perfect sync.

[okuma1984]

Facing would be under P10 and turning would be under P20 for both turrets. If you use a canned cycle, you will need to Pcode every line inside the shape definition from G81 to G80 to keep them in perfect sync.

ok cool so is there a canned cycle in Okuma? you know the G71 Roughing G72 facing G75 grooving etc etc in Fanuc language? is it structured the same way as Fanuc?

[deadlykitten]

or is that WAIT 10 seconds before you start the next MOVE?

hy, to make a program wait 10 seconds, or dwell, is required to use G04 F10

you may also use decimal arguments ( eq G04 F1.234 )

if you are intersted, there is also a parameter, to switch the argument measure unit, from seconds to revs ... but you can also do it directly, like this G04 F0.5*60/rpm ( delay for 0.5 revs )

if you wish for a program .... to TAKE AS MUCH AS 10 seconds ?

you can not impose the duration of a program at least not on okuma

ok cool so is there a canned cycle in Okuma?

pls find attached the programing and special functions manuals ... those are for actual osp, but basics haven't change

hmm, those are too big for upload, so pls check this download link : https://we.tl/t-rPUQJCVpXB / kindly

[OkumaWiz]

Yes there are canned cycles. Their G85 roughing cycle works even better than Fanuc's routine (no stair steps). G87 is the finishing routine. Look in your programming manual under LAP cycles (lathe auto programming) for the details. There are also G74 drilling, G71 threading, and more in the same book. Different codes, but same in general principals.

[okuma1984]

got it. thanks. quick question for you guys
have you tried replacing the chuck on your Okumas? if i want to go from 8" to 12" chuck? ? i know i am gonna need a back plate and a drive nut adapter so
would you make these yourselves or would you contact kitagawa for that?

[deadlykitten]

hy it's cheaper if you can do it; you will also need to edit some parameters, so to lower acceleration & breaking, maximum rpm , static torque for c axis, and maybe others, but i don't know where are those for your machine

i would avoid the adapter, and craft the entire piece instead

why do you wish to increase the chuck size ? custom jaws aren't enough ? pressure should be similar for both, arround 2.7mpa, but, if you wish to increase it for the 12", then check if the hydra cilinder can raise up to the task, and don't forget to restore it when you'll go back to the 8" / kindly

[okuma1984]

hy it's cheaper if you can do it; you will also need to edit some parameters, so to lower acceleration & breaking, maximum rpm , static torque ( and maybe others ), but i don't know where are those for your machine

i would avoid the adapter, and craft the entire piece instead

future ( not futuristic ) advice : don't forget to lower the hydra pressure when you will go back to the 8"

why do you wish to increase the chuck size ? custom jaws aren't enough ? pressure should be similar for both, arround 2.7mpa / kindly

yes pretty much i never liked 8" chucks. i wanted to upgrade to a 10 at least but then i got a deal on a Kitagawa B212 so i said what the hell. i'lll have two machines with two 12" chucks!!!
so when you say craft the entire piece this is the adapter nut i am looking at were you referring to a longer adapter than the standard ? with 50mm ID?
i can buy the back plate i just figured it it's simple enough to machine. the same with the Nut adapter here from Kitagawa


https://www.mscdirect.com/product/de...12&hdrsrh=true


Adapter Plate 10"/12" (A2-06) 25T - Samchully Workholding, Inc.

[deadlykitten]

i never liked 8"

depends what kind of parts you are crafting; 8 vs 12 is speed vs power ...

upgrade to a 10 ... deal on a Kitagawa B212

what is the standard chuck size for your machine, and/or spindle nose ? is that b212 new ? power requirement & wear are greater for a bigger chuck

two machines with two 12"

is ok if you are regulary crafting parts with big diameters, like > cca300mm

you know your parts, just think about if it's better to have 2*12 or 12+8 or 12+10 ... temperate that hot-deal

so when you say craft the entire piece this is the adapter nut i am looking at were you referring to a longer adapter than the standard ? with 50mm ID?

is just a nut ... i have technical drawing for spindle noses & bore, drawbars & chucks, so i could check some dimensions ... in the end, is required that the new chuck, when is opened ( for normal od clamping ) to have little clearance inside, in respect to the wedge plunger .... doing this, requires to corellate the actual drawtube travel length and position with the new one, through the drawnut

if you would talk with kitagawa about this, they may sell you stock parts, or require the machine type and hydraulic cilinder, and, if you are lucky, this combo may be inside their database, otherwise they may still need to design a new drawnut, and i don't know what they would say about going from 8 to 12, because the gap is 2 sizes ... normaly, gap is ±1size, so ...

all this is needed to avoid downtime caused by mounting and unmounting the chuck, in order to see how it behaves ... in some cases, short & quick solution is to rotate the drawbar or the drawnut, but if they are not tighten properly, then threads may get damages ... in a good designed machine, the drawbar is almost tightened as far as it could, and the drawnut is rotated a few turns, to adjust the clearance between chuck and plunger; on cheaper machines, that clearance may be 30-40mm, while on okuma's is smaller, and also, some adapter plates are thicker than kitagawa standard ( cheap vs safety ... that's one thing to consider )

i just figured it it's simple enough to machine

there may be some particularities, making it a bit more chalenging : the internal diameter may not be cilindrical, but conical, or conical & cilindrical, and there may be also an excentric tolerated hole, designed to avoid sending torque direct through the screws

i am not saying that is not simple, but is better to have a drawing with tolerances and conditions, so to avoid wobbling the chuck / kindly

[okuma1984]

understood. what about the back plate though? have you tried swapping one? is there a taper?
that plate from Samchully looks like a mild steel that's not hardened. we are talking about a 8" ring with a 4" ID right? would you have specs for that and i can probably do PCD holes on CNC mill.
there is also one by Bison.
https://www.globalindustrial.com/p/m...nch-a2-6-mount

[deadlykitten]

to avoid doubts, i would recomand to get the dimensions ... or at least check that you could return the item if it does not fit

at least actual jis a2-6 and a2-8 spindle noses are dual tapered, od - for chuck ( or plate ) centering, and id - for spindle alignment / kindly

[okuma1984]

to avoid doubts, i would recomand to get the dimensions ... or at least check that you could return the item if it does not fit

at least actual jis a2-6 and a2-8 spindle noses are dual tapered, od - for chuck ( or plate ) centering, and id - for spindle alignment / kindly

like what am i thinking? there has to be a taper. it's A2-6 now instead of A2-8 maybe i'll just buy that but if i could fabricate it myself it would be under $100!

[deadlykitten]

plate has to run true, thus frontals to be paralell, diameters concentric, and frontals perpendicular on diameters ... so far so good, but the only trick is to create the taper to comply with those conditions, and also to craft it within tolerance

crafting/refreshing a taper for a tailstock is easier, because it's long and small, while spindle nose taper is bigger and way shorter ... this makes it harder to bring the part ( the plate that you are crafting in-house ) at the cnc-lathe, check for contact with spindle nose, then go back to grinding & and re-center it, in order to cut a few more hundreds

if i would craft such a plate, i would 1st check & detect the spindle tape ( using in-machine measurement=imm* ), then :
... craft a part that has a similar taper on it, so to use it as a gauge when machining the in-house plate
........ or
... start machining the new plate inside the other lathe, using similar imm* as before; like this i would achieve a true ( within lathe condition limits ) inner-dia + outer_dia + face; then grind the 2nd face, and perform a final control, so to detect how "true" it is ... rest is easy, involving a few holes, threads, deburring, etc ...

there is needed as good contact between tapers as possible, and as low play with the chuck as possible, so i would pay attention to these :
... measurement consistency when detecting spindle nose taper
... repetability when turning the taper inside the lathe, and here it helps to use a slow approach ( not rapid ), slow feed, and droop control ( or big clearances, so to ensure in-position ) + small doc and sharp tool
... measurement consistency when detecting chuck id diameter ( where the plate goes in ) : there is a big diameter that is relatively short, making it hard for id measuring tools to fit in, but for a 12" chuck it should be easier than for a smaller chuck

seems that jis taper is 7*7'30, thus 7+7.5/60=7.125 decimal degrees; at my last measurement, i detected a taper deviation between 1 - 4 um / 15mm

i don't know ... if you wish to craft it yourself, start with measuring the spindle nose & chuck, design the plate to fit both spindle and new chuck, make it thicker than a standard market one ( like + 10 ... 15 mm ), and maybe consider to have some spare material, in case the 1st plate will need improvement also, when the plate goes inside the chuck, it may be tricky to assamble it by hand, since parts are heavy, and only after the plate is inside the chuck, only then you may really check the play between the plate and the chuck ...

is required a bit of patience, since diameter's tolerances are arround ( few ) hundreds, and diameter's length is small, thus is a ' fit ' part with low L/D, but it can be done / kindly

ps : if possible, try to target a play between plate-spindle taper, and plate-chuck, that is <0.015, so to avoid having, in the end, a chuck tir > 0.030; you may achieve a really low play with the spindle taper, like < 0.006, and target a bigger play with the chuck, like 0.020, in order to mount easier the plate inside the chuck

[OkumaWiz]

Kitty, Kitty, you've got more wind in you than Hurricane Laura...;-) He needs a drawtube adapter nut to fit his current drawtube and a spindle adapter to go from A2-6 or A2-8 spindle to his chuck. The A2-8 is for the big bore spindle vs A2-6 standard bore. The 12" chuck adapter can either be bought from Kitagawa or made locally. It is very accurate, so be sure of what you are getting into if you try yourself. That being said, if it is a little sloppy, you can "dial it in" by loosening the bolts to where they are just snug and use your precision alignment tool (dead blow hammer) to nudge it onto center. It should run within .0005" when finished.

When done right, you should be able to put the old 8" chuck back on with no issues using the original drawtube.

[deadlykitten]

hello again, machine catalogue presents a2-6 only with 8" and 10", while kitagawa sells a plate also for 12" chuck

mounting a 12" on a2-6 requires:

... mount the plate to the spindle, using 6 x M12, check od tir, frontal tir, clearance with spindle frontal, and contact area with spindle taper ( don't rush, a plate that is out of spec may loose contact between tapers, even if it feels steady ):
......before mounting, surfaces should be clean and dry, no oil, no dust
...... it should show nice tir values after it had been mounted only with carefull hands ( + maybe verry gentle tapping with a soft hammer ), just like how a livecenter goes inside the tailstock, or a toolholder goes inside a mill spindle taper; conical contact, after it occured, should not be adjusted, but only measured
...... before tightening the screws ( between plate and spindle ), it should be hard to pull the plate back only with spare hands, thus force required to pull it back has to be much greater than the initial force required to mount it

... mount chuck on adapter plate, using 6 x M16, then proceed to chuck tir adjustement :
...... at least 2-3 screws has to be only approached, thus tighetened ligthly, so to allow the chuck to slide in vertical plane, but not to move orizontally
......... this pre-tightening step is important : if screws are too tightened, then :
............ it will be required to apply much more force, in order to achieve same tir correction, when compared to a less tightening scenario; this amount of extra-force may affect the bearings
............ tir will increase among a direction that is not along the direction of the force that has been applied ( for example, if you hit among a direction=d1, then tir may increase among a direction=d1+90degrees )
......... is harder to reduce tir on a heavier chuck, so here is a tip : hit the chuck vertically, from underneath it; like this, it can immediately be seen if screws are tightened enough to hold the chuck mass, but loose enough to allow easy tir adjustement; force applied during tir adjustment should be as minimal as possible, and almost entirely transfered into tir correction among force direction, without tir changing among a direction that is not coaxial with the force; if done corectly, should allow reaching 0.03 in few minutes, then start to gentle tighten the screws and reduce tir even more as you continue

above method works only for chucks that have the od in good condition; if chuck od is deteriorated because of roughing operations, then is needed to change the approach

mounting a 12" chuck on a2-8 requires less time, since the chuck is tightened directly to the spindle, but this is not your case

if you wish, before starting, measure the play between plate and chuck, so to know what runout to expect / kindly

Kitty, Kitty, you've got more wind in you than Hurricane Laura...;-)

i am glad you feel it and i heared that hurricanes always have female names ...

[deadlykitten]

the internal diameter may not be cilindrical, but conical, or conical & cilindrical

me again : plate's width may be > spindle's taper length, and plate's interior may be cilindrical & conical, in order to shorten the contact length with the spindle's taper and assure that contact is toward the bigger diameters ( means safety, more rigidity, also spindle section is bigger in that area )

is not critical for a conical contact to occur all over the cone length ( thus it may be impartiall ), as long as contact is starting among the big diameter ( and, obviously, get's lost toward's the smaller diameter); for example, if you are machining heavy parts inside a lathe, and livecenter housing is making contact only arround 60% of it's cone length, and this contact area is not located toward's the bigger diameter, but towards the tail, then rigidity is lost; if this is realized in the end, and is decided to change ( or refresh ) the livecenter, then, is possible, that the "new" one will be "floating" in there, struggling to find contact area, because, even if it is in good condition, the other cone ( the id cone of the sleeve ) was deformated ( too much time working under increased pressure )

from time to time, i check contact area for conicals :
... spindle & plate taper, when cleaning the chuck ( once / year ) : check spindle's taper surface for damage
... tailstock housing : check contact area, always with same live center : it is >90%, getting a bit lost toward the small diameter
... mill taper : check toolholders wear, and inspect spindle
... live tooling : keeping surface clean, mimimizing collet rotation inside the chuck, and always cleaning the grooves for chips ( i have a ~0.4 thin metal foil )

in most cases is all fine, until a part that is out of spec appears :
... a livecenter may damage the housing
... a toolhodler may damage the mill spindle, even if it's used only a few times
... if a lathe spindle adapter is crafted with inapropiate tolerances ... hmm
... but nothing escalates as quickly as for mill dual contact spindles

checking contact area for tapers :
... small tapers : at least one part can be rotated by hand ( like a livecenter, or a collet ) : use a thin marker ( the trail may be as thick as the marker's tip, but the film, in section, has to be small : thus is like paiting with a low density paint : you cover a great area, but layer thikness is small )
... heavy tapers : there are some sprays, but it may be tricky to use them from both sides, so here is a tip : use a 'sticky' liquid : for example, is possible to see a footprint on a wet surface some types of oils will not work, they will create a film that may not allow the tapers to get in touch, acting like a little tiny thing that does not wanna be squished ( there are mechanical assemblies, built on this principle, with shinny surfaces and a thin hydraulic foil, in order to reduce friction; there are air flows capable of reducing friction between 2 surfaces )

if you decide to craft your own plate, if you wish, i may help you with specifics / kindly

[okuma1984]

i heared that hurricanes always have female names ...

it's because "When they first come they're wild and wet, when they leave they take your house and car with them"