PPG K38 Paint Help.........

[1hot68]

Never said it said you had to spray at 70 degress, he said being 90 degrees it's drying to fast for him & tech sheet gives no options/ alternatives to slow down drying time. Ihot68 seems to be saying since no options on tech sheet nothing you can do to slow it down, only thing you can do is go by tech sheet.  All I know is I dont have this problem with my primer spraying. Seems everybody else in here has the answer for him so I'll stay out of this conversation from this point on. LATER.

What I meant about staying with the tech sheet was about the the mixing of the primer. The temp should only change the way its sprayed!

If its hotter than 70 the flash times between coats will be less and if its cooler than 70 you will need to wait longer for it to flash between coats.

My main point is that you should never mix things into a product that arent on the tech sheet!! If it was widely accepted to add something to it the techs would have it listed in the sheet! When you are dealing with a chemical there are enough variables without throwing in some reducer or enhancer etc. into the mix too. 

[hemi-hampton]

Heres what one of my PPG Gun chart has to say. Some say a 1.8 tip to big but here it is in black & white from PPG themselves. All I know is that out of 25 years of spraying my rule of thumb is the thicker the material the bigger the tip. A .08 tip is good for super smooth atomization on certain products.

[69 OUR/TEA]

Don't want to ,but the chart says the 1.8 is for a larger fan for going faster and complete jobs.Pretty much I prime panels individually,maybe two at a time,thats just me.That chart shows the PRI gun as the gun for using the products metioned,K38 using a 1.6 tip.Drop down to where it shows sealers,as I said I have/use a GTI,cross over and it shows for the same jobs it uses a smaller tip,so the gun apparently atomizes differently than the PRI.It does not show reccomended tips for when using a GTI for their primers,but I still use it for priming,and as I had said I use mine with a 1.5(the gun came with 1.3,1.4,and a 1.5),no problems.One more note,as has been mentioned that since K36 offers a reducer that can be added by the tech sheet,and K38 does'nt,note on the chart showing the smallest tip for K36 is a 1.4 and the K38 being a 1.6(with the PRI gun).That is pretty much showing you that the two products are different and don't assume that because you can put reducer in K36,that you can do the same to K38.
  Anyway,as I said,I think the biggest problem that 68mmcharger is having is with his gun,and before he calls the primer the culpret,get a new gun,a name brand one from an autobody supllier,not from home depot.:FWIW,NCP271 is my primer of choice from the PPG lineup.Twocents:

[68mmcharger]

Sprayed some more K38 today. Tried taking the strainer below the paint cup out and gun worked much better. At least now I get a steady spray at risk of clogging spray cap. Had to narrow fan width down and move fairly slow to get a wet coat. Surface is a LOT smoother. My Ingersoll Rand gun came from a tractor store, not Home Depot. Does that make it better??

Temp was 82 in shop today. Primer sprayed better. At least I was able to get 10 ounces down without it drying in gun.

Will the PPG tech line guys talk to anyone that calls?

Kevin

[hemi-hampton]

You said yourself the 1.8 is for moving faster, If it is drying to fast & your moving to slow then you want to move faster. 


P.S. Charts back up what I been saying. 1.4 for k36 & 1.6+ for k38. Why, Because the k36 is thinner then k38 especially when reduced & used as a sealer. I thought all this was common knowledge & common sense.

[69 OUR/TEA]

Seems everybody else in here has the answer for him so I'll stay out of this conversation from this point on. LATER.

     
     

. Better use a 1.4 for smoothness. Have fun. LEON.         

     
              make up your mind

[hemi-hampton]

I was being sarcastic with the 1.4 comment.

[83CHARGER2.2]

Hey Kevin,  This seems odd that you are having these problems and so many folks are arguing back and forth over the situation.  I have a good friend who IS a PPG rep and he indicated to me that in the south, where are temps are hot, it is obvious that a bigger tip gun is needed to spray in a hotter environment.  A 1.8 is a standard spray tip for a primer gun.  If some folks are using  a GTI with a 1.5, well then that setup in a GTI Devilbliss may be a good combo, but a 1.5 in a typical GRAVITY (BECAUSE NO ONE SPECIFIED WHAT THE GUN IN QUESTION WAS YET) feed a normal Clear tip. 

My PPG friend said that 1.8, with K38 is a perfect set up.  Normal spray pressure of 25 PSI or what ever the GUN not the P Sheet but the GUN requires at the tip, is what is to be used.

The Tech Sheet is just that.  A tech sheet, which is produced for IDEAL conditions, and as we know that is why chemicals need to be altered, as most do it yourself individuals do not have ideal conditions. 

It sounds like the correct gun, with the correct mixture and additional reduction as needed would cure your problem all together.  I have had to add reducer and even extender as I stated previously, to K38.  In nature K38 is a great FAST primer which is nothing more that K36 with more talc in it to produce a higher build.  Once finished with the Gallon of K38, try using DPS3055 which is a K36 type primer (ISO) that is slower to work with. My PPG Friend said that is why this product was created.   The PPG Tech line at 440.572.6100 can always help as well.

The best solution for most paint problems is experience and giving yourself an education so you do not have the same problem in the future.

[68mmcharger]

Thanks for the info 83CHARGER2.2.  I will contact the PPG tech lilne regarding a K38 reducer/extender.

Looks like I need to replace my Ingersoll Rand gun since there are no tip options for it. I have been looking at the Devilbliss FLG-653B Master Kit at tcpglobal.com. They have this setup for $229.00 which comes with a 1.3, 1.5, 1.8 and 2.2 mm tips, case and regulator. Does anyone know how this gun compares to Devilbliss's GTi-620G? The GTi is $359.00 with a 1.3, 1.4, 1.5 mm tip, case and regulator.

[68mmcharger]

Talked to the PPG tech line today. He said there was no extender available for K38 to extend pot life. Looks like I will just have to deal with the short pot life.

I ordered a Devilbliss GTI gun with the 3 tips tonight, hopefully I'll have it before this weekend. 1.5 is the max tip size in the set. Probably should have ordered the 1.8 at the same time but I'll try the 1.5 and see how it works.

I'll keep you guys updated.

[69 OUR/TEA]

Hey Kevin,
that's good,you'll be happy with that gun.One thing you can get for the GTI is the ziplock bag kit,works great,allows you to spray upside down and makes cleanup of the gun simple.I only use it when I am spraying paint,(base and clears),epoxy and sealers.Primer is just alittle too thick to get through the small plastic bushing that you install in the bottom of the gun with the bag.Also,a good starting point for you with the GTI when spraying primer,turn the fan control on top all the way in(clockwise),back out about 1/4 turn and try it there.That's around where I spray with for priming,yeah the fan pattern is'nt huge,and you'll have to go a little slower,but you should find it will work fine with the 1.5 tip.
  BTW,did the tech line  tell you to add reducer? Also,when you're all done with your stock of K38 try NCP271,I think you'll have found you're new favorite primer.Take care

[68mmcharger]

69 OUR/TEA - Thanks for the gun set up tips. The PPG tech line said there was a reducer but all it would do was extend the dry time, not the pot life. We didn't discuss which one since it did not provide what I was looking for.

Does the GTI have a strainer below the paint cup? If so, do you leave it in with K38.  My existing gun worked much better with the strainer removed but still not right.

Kevin

[69 OUR/TEA]

No strainer in this gun,take it out no matter what gun,and whatever you are spraying.Just strain the paint with the disposible strainers given to you from the paint store.Good luck Kevin.

[83CHARGER2.2]

Kevin,

Dont forget, a GTI is a finish gun, not a Primer Gun.  The GTI which was recommended by another post is a great gun, but a finish (Base clear) gun.  Nothing is said that you cannot use this to spray primer, but any one who knows up to date spray guns will tell you to use a primer gun to spray primer, and a finish gun (GTI) to spray top coats. 

A GTI's air cap atomizes the crap out of the material spray, eliminating most of the solvent in the spray procedure.  That is what I was getting at before in a preivous post.  A primer gun will leave the solvent in the mix to get it on the panel and to allow it to flow slightly.  The primer gun will also have a huge tip for the higher solids products.  A primer is a higher solids than a clear or definitely basecoat.  The basecoats and clears need the atomization at the tip of a gun like a GTI so that it removes those solvents at the spray procedure.  A primer does not have any where near the amount of solvent in it that a base coat color does, therefore the solvent in the primer, needs to stay in the primer so that you do not get extremely fast drying primer.

You may still have the problem with the GTI even with the BiG tip (1.8, 2.2, etc)  Good luck.  A perfect inexpensive primer gun is a Devilbliss finishline with a 2.0, or a Plus with a 1.8.  ( A plus can be also used for finish coats, but is not an HVLP Gun, but VOC Compliant).

There was a reason that Hemi-Hamptons' PPG chart put the GTI in the sealer category, because it is a topcoat gun.

Good Luck!

[hemi-hampton]

Wow, your the only guy to listen to me. I guess only you & me noticed the GTI was not listed on my chart in the primer surfacer category for a reason. The reason it was deleted & not a option is because the 1.5 is the biggest tip available it seems for that gun.  LEON.

[83CHARGER2.2]

Talked to the PPG tech line today. He said there was no extender available for K38 to extend pot life. Looks like I will just have to deal with the short pot life.

I ordered a Devilbliss GTI gun with the 3 tips tonight, hopefully I'll have it before this weekend. 1.5 is the max tip size in the set. Probably should have ordered the 1.8 at the same time but I'll try the 1.5 and see how it works.

I'll keep you guys updated.

Kevin,

Forgot to post this earlier but D886 is a universal extender for the entire Global line that will work fine in K38. My paint rep recomended this to me.

[68mmcharger]

I got in the GTI gun and used it to spray a couple of coats on the fenders with the 1.5 tip.  It works MUCH better that the IR gun with the 1.4 tip. It at least provides a steady spray and a smooth coat if I go slow. I will have to use it some more to decide if I move up to a larger tip.

Leon - Tips are available all the way up to 2.2 - $55.00 +shipping.

83Charger2.2 - Is there a recommended mix ratio for D886 with K38?

Your logic on the base/clear gun certainly makes a lot of sense. Is the atomization a function of the cap only vice the gun body? Looking at the Finishline 3 info it appears Devilbiss calls their guns a primer gun when you get into the 1.8 tip size range. Appears that the body is the same.

Kevin

[83CHARGER2.2]

Kevin,

I talked to my buddy who is a PPG rep again today.  He said, and I thought this was correct in my head but I wanted to confirm with him.  D886 which is in the Global PPG line and DX54 i nthe Delta Line are basically the same product. They are created to extend the pot life of a ISO CYANATE product.  In other words any ISO primer, clear, sealer, etc.  K38 is an Isocyanate primer and either the D886 or the DX54 extends the pot life.  The mix ratio is 1.5 ounces to Ready to spray quart.  So, 1.5 ounces per 32 ounces of mixed (primer and hardener mixed together) primer. 

The guns I know about,  the GTI is again, a great topcoat gun, but not a primer gun.  The air cap is specific per gun.  So they are not interchangable like the nozzle.  The needle has such a taper in a GTI that it can accept various sizes of tips or nozzles, but the air cap is specific per Devilbliss gun.  Prior to the GTI millenium, there was a straight GTI which took a No. 100 air cap, again different than your GTI millenium.   Hope this helps.

[hemi-hampton]

  hhmmmm, Isn't that what I said/implied LEON.

[Todd Wilson]