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CP6 Nozzle sticking

It seems that every time we do maintenance on our CP6 windmi... - Feb 15, 2005 by Sr.Tech  

#32649

CP6 Nozzle sticking | 15 February, 2005

It seems that every time we do maintenance on our CP6 windmills, we have a lot of problems with nozzles sticking up inside the holders. It seems to happen for a while, then it goes away after we run for a bit. We follow the Fuji maintenance procedure to the T.

It is a real problem because when the nozzles are stuck they sometimes still pick parts and pass vision. When it goes to place the part the Z height is way off, and the parts go flying.

This happens with both Fuji OEM nozzles and after market nozzles.

Has anyone ever seen this ?

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jdengler

#32651

CP6 Nozzle sticking | 15 February, 2005

I had a similar problem on another machine. It turned out to be the wrong oil used on the nozzle shaft. This oil was a higher viscosity, which caused the nozzles to stick at start-up. After the machine ran for a few minutes everything returned to normal.

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#32653

CP6 Nozzle sticking | 15 February, 2005

Lube on the nozzle shaft ? I didn't see anything saying to lubricate the nozzle shafts !!??

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jdengler

#32654

CP6 Nozzle sticking | 15 February, 2005

It wasn't a CP6. I don't know if the CP6 needs lube or not. It just sounded very similar to a problem I had many years ago.

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Dougs

#32657

CP6 Nozzle sticking | 15 February, 2005

I've seen this before. I had a CP6 doing this for a while, replaced the nozzle springs with ones wound the opposite way from the fuji ones. replaced the springs with these and never had the problem again. you can get them from Ritchie precision engineering in scotland.

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Alan

#32667

CP6 Nozzle sticking | 15 February, 2005

I have also seen this before on a CP6.

We had an issue once on a CP where the shaft was coming down too far at stn 1 for pick up and forcing the nozzles up and sticking in the windmill.

Check that the correct spring type is being used. Also, maybe a part data height is wrong, causing nozzles to be forced into the windmill. If it is a part data, you will find one size of nozzle getting stuck.

Good to to check that the ZO is correct on your machine too.

Never use any oil on nozzles. We clean out the windmills with Threebond cleaner 6602T. This is great stuff as it cleans and doesn't leave any residue.

I hope this helps you out.

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#32668

CP6 Nozzle sticking | 15 February, 2005

Hello Snr Tech, kindly isolate the problem if it's coming from the indentified holder or the nozzles itself, by swapping between holders.

there will be oxidisation on aluminium, from which your nozzles are made after a period of time. impurities, sratches on the nozzles do contributes to the nozzles sticking up into the windmill.

changing the nozzle spring coil direction MIGHT cause the nozzles to "unlock" & "fly" out of the holder during production.

dimension of the nozzle is critical. for more information, kindly write in to apexservice@apexsmt.com

Good Luck

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aj

#32677

CP6 Nozzle sticking | 16 February, 2005

Check to see if its the same component everytime if so check part height .

Also check Z0.This setup is in the manual.

You say this only happens after maintenance is carried out so when you free the nozzle it doesnt happen again until maintenance is carried out again?

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Alex

#32972

CP6 Nozzle sticking | 1 March, 2005

I've just went thru cleaning all nozzles and I saw some of them stuck up. The reason for mine is that they're on the way out, between lock and the exit notch. I tried to reinstall them with the spring "forcing" the nozzle clockwise. Sound weird but I'll see if it helps.

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Dave Erbst

#33001

CP6 Nozzle sticking | 2 March, 2005

Try checking your Z height and also make sure that they are cleaned regularly. If the Z height is off your will be pressing your nozzles into the holders thereby causing them to bind up inside the holder. Replace the springs periodically since they do wear out. Also make sure that the vendor you purchase them from holds very tight tolerances. When measuring your nozzle lenghth measure from the bottom of the pin to the tip of the nozzle it should measure 12.25mm to be exact. I think you will find a lot of vendors do not hold very tight tolerances.

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#33004

CP6 Nozzle sticking | 2 March, 2005

I bet SMT research has good tolerances lol

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Dougs

#33023

CP6 Nozzle sticking | 3 March, 2005

I'm telling you i've bought the nozzles wound the wrong way and it helped, no more probs with nozzles sticking, i'd tried buying fuji nozzles, checked all my component heights, set Z0 properly, checked shaft heights, set up st1, etc etc but the new springs worked.

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Dougs

#33070

CP6 Nozzle sticking | 7 March, 2005

not nozzles - springs - DOH!!!

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#33082

CP6 Nozzle sticking | 7 March, 2005

--IE, Funny.---

I "remember" kinda, from the early CP6 years, things about the springs. The early Fuji springs had sharp ends, and if you spun the nozzle, prior to final attachment, the opposite way it could stick, and if it was spun the right way, that would hide 2 problems. The first, as you have already been reminded, is Z pick-up and Z0, technically the nozzle should never "bottom out", but in production, it will sometimes be unavoidable. The other is how the widmill is machined. Fuji went thru several spring, windmill, and nozzle changes, I think the biggest was the windmill. If you push the nozzle up with your finger and it sticks, it will occasionally stick during production. If there's a "rounded" corner where the catch pin rides in the windmill, it will always rotate and stick on the on the opposite corner. I guess that Fuji changed that on newer holders. If this is a serious problem, consider milling, filing, or grinding that little radius off the corner where it forces the nozzle to rotate when fully inserted. Do not dissassble the holder, just remove the dog ring, otherwise, you'll have to call Dave Erbst.

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#33091

CP6 Nozzle sticking | 8 March, 2005

Guys,

Thank you very much for your responses. You have been very informative. As soon as I find out what is going on for sure I will post again.

Much thanks,

Sr.

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#33105

CP6 Nozzle sticking | 9 March, 2005

Ya know,

The weird part is that we seem to have a real bad rash of nozzle sticking right after windmill PM's. After the machine runs for a week or so it seems to get way better. Like 99 to 100 % better. This leads me to believe that it is not a Z height thing.

As I said, we follow the Fuji PM procedure. The only thing that I could see as a potential problem is the solvent I use to wash the wheel in.(plain mineral spirits) Some of my techs are questionable as to whether or not it is leaving some type of residue...

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Fred Calkins

#39171

CP6 Nozzle sticking | 18 January, 2006

Since this happens just after PM and you mentioned solvent in an earlier post, I suspect that the solvent is washing a light grease film from the turret shaft area into the bore that the nozzle fits in. I think that the nozzle shank and bore must be absolutely dry or a black deposit forms on the nozzle shank.

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#39175

CP6 Nozzle sticking | 18 January, 2006

Since I have posted on this last, we have found that 99% of our nozzle sticking problems are do to part height problems. I have been told that CP6 machines are very sensitive to part height do to the amount of spring travel in the nozzle.

If you have a part height description that says a part is shorter than what it actually is, the nozzle will stick. I am not quite sure what the amount of error is that will cause sticking, but it is a very small window.

I have also been told that there are mounting holes and places in the wiring harness to mount a sensor that will sense whether or not you have a stuck nozzle. For some reason Fuji decided not to finish installing the sensor.I am pretty sure all CP642 machines are like this.

It is also critical that you check the Z zero on these machines as well. We are actually making checking the Z zero part of our PM's. The table level should be checked on a regular basis as well.

I have been working with an after market place that services Fuji's and they tell me that they sell the sensor set-up that checks for stuck nozzles. I can't tell you what the cost is as I am still awaiting a quote from them.

So in all, I think I was incorrect in assuming the stuck nozzles were PM related.

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Curt Couch

#39253

CP6 Nozzle sticking | 21 January, 2006

Sir, reverse wound springs do help this situation. I would also recommend using acetone in the wind mills, its made of 440C SS and has R/c hardness of 58-60 you need to use something that will cut the gauling deposits left from the aluminum in the nozzles. Also mic. the nozzle diamiters, they should be around .1962" - .1965" they should also be round and concentric. Clean heads could expose nozzles out of round. Are you using Fuji nozzles or someone elses?

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#39293

CP6 Nozzle sticking | 24 January, 2006

I have some old Fuji windmills here and I checked the usefull travel. It is approxiamately 1.5mm, the nozzles are suposed to have .3mm "preload" wich will take away from the usable overtravel. The windmill I checked is a reject that from when we rebuilt them here. I checked each nozzle position for the extended height and they varied .15mm from high to low reading, this will take away from usable overtravel. There are several other sources of variation than can lessen your usable z travel. #1. the stop screws that the older machines pallets rest on become dished and the pallet height will vary when it lands on different portions of the uneven surface. New screws are the answer here. Fuji's part # is WSZ1070, we do make these. #2 Board warp. I do not know how you all fix this. #3 you already mentioned componant height. #4 Headshaft height this is the distance from the rollers to the windmill mounting surface. There is a way to set all the headshafts to the same height on the machine, I have an article on this at http://www.nozzlesupply.com under Nozzle Info under tip #3. #5 Is the height of the nozzle from the crosspin to the tip. New fuji nozzles are held very close, The nozzles that we make are held to 1/2 of the tolerance that we have seen on Fuji's. Mr. Couch who also responded to your post probably holds a fairly close tolerance on this measurement. We have one major competitor whose nozzles start at Fuji's low tolerance and go to .15mm longer than any Fuji nozzle I have seen. This is not good because extra long nozzles do not give you any extra life. The difference between your shortest and longest nozzle is a source of z travel problems. When we retip nozzles that are not bent or damaged they are usually .15mm shorter when they are returned to us. I do not know the practical limit for wear but it can not be more than the .3mm "preload" minus the other variables.

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dougs

#39302

CP6 Nozzle sticking | 25 January, 2006

thats an expensive looking jig for a calibration that you do on the machine using a dial gage.

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#39304

CP6 Nozzle sticking | 25 January, 2006

Doug, If you saw our calibration tool (Blue) it is for setting the head shafts off the machine. It probably is too expensive for small shops with a few machines to maintain. We sold them to three plants that were maintaining 60 or more machines. The fixture has the advantage of doing the job faster and more accurately than the on machine method. We do have a fixture here that we can set yhe heights here if someone has the time to ship us their head shafts. We could do them for $200. and ship them back the same day. If you saw the article I did describe the on the machine method of setting the shafts.

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dougs

#39317

CP6 Nozzle sticking | 26 January, 2006

i didn't see anything about setting shaft height there, only a procedure for measuring nozzle length. just out of interest, whats the cost difference between a re-tipped nozzle and a new one from fuji? And how much is one of those shaft jigs?

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fredc

#39319

CP6 Nozzle sticking | 26 January, 2006

My mistake it was tip #2. I am not sure about Fuji's price now, but our rettips were about 1/3 the price of new. The cost difference between our new and our rettips is only two or three dollars depending on quantity. There was a time when the cost differential was much higher, but the savings are still worth it for some customers. The last time we built a headshaft setting machine it was around $4000. That was several years ago, I am sure that the indicators and linear slides are higher now. One thing that might make it cheaper is the new headshaft's blow off spool does not need to be set. That would eliminate one indicator, one linear slide and the calibration check block. When we made the first one we understood that Fuji had such a machine but it was not for sale, now we have heard that they sell them.

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#39323

CP6 Nozzle sticking | 26 January, 2006

Quick question fellas,

Why would you ever have to check your shaft height ? We have been running or CP6 machines for a while, and I have never seen a need to check this ???? Should I be ?

I'm confused..

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dougs

#39333

CP6 Nozzle sticking | 27 January, 2006

Yes you should check your shaft height every now and then, or if you need to replace a shaft it shows you how to do it in the maintenance manual i'm sure.

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fredc

#39341

CP6 Nozzle sticking | 27 January, 2006

If your have enough hours on a machine that you have all the windmills off for maintenance, it would seem to be a good thing to check this height. It would take only a few minutes to put a dial indicator in and manually crank the machine to the bottom of the travel on all 20 positions. If you have had a crash and the machine is having z problems in one or more positions.(The first plant that ordered one of those fixtures had something happen with the blow off and moved all 20 headshafts I let them use the fixture before it was finished to get the machine back into production.) If you had one or two positions with sticking nozzles and could not find the problem I might compare one of adjacent shafts to the offending ones to eliminate the possibility of the headshaft being the source of the problem. One thing to throw out to you guys that use these machines, does the height of the feeders cause any problems. I can see several possibilities that would drive the nozzle too far. #1 debris under the feeder, #2 tape guide problems, #3 tape with inconsistant depth of pockets. You have already mentioned componant thickness. It seems like a some of the nozzle sticking problems could be coming from the pick up side of the machine instead of the placment side.

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