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Stop pouring money the drain in your bodyshop Part 1

Money drain

It is not a secret that a body repair shop, regardless of its size, is a business; and every business is designed to make profit for the owner/entrepreneur who invests his money and expects return on his investment. The more profit a bodyshop produces, the better for its stakeholders (the owner, employees, suppliers etc). So, what shall we do to increase the profit? Well, you can write a book of a size of Tolstoy’s “War and Peace”, but without a doubt, if a body shop manager will spot where money go down the drain in a shop’s operations, it will help to optimize the  profit. In the first part of this series of articles, I will draw your attention to two of such money drains: paint over mixing and spray gun efficiency.

Mixing paint quantities

Believe it or not, but the waste of materials, which were over-mixed for a particular paint job may increase the overall paint (clear, primer, filler etc) consumption up to 20%. The biggest wastage occurs with 2K materials, which have a very short pot life of a ready-to-use mixture. I have seen many times how a painter was pouring into sink half cup of clear coat, simply because the working day was over and tomorrow the material will be already cured. This is about 200-250gr of the material!

Paint mixing

Why it happens?

There are a few reasons why a painter is mixing too much material for a given job:

  1. Lack of experience with a particular product. As we all know, coverage and consumption from product to product may vary dramatically. For example, UHS clearcoat may need only one full layer with a mist coat to get 60 microns of thickness, while certain MS clears won’t get such a film thickness even in two full coats. The difference between primers and fillers can be even bigger. So, please familiarize yourself with the material you use, study TDS and get used to it. Don’t change the materials used in a bodyshop too often.
  2. Overall professional incompetence of a sprayer. Unfortunately, badly trained people in a bodyshop are the biggest problem. Every bodyshop owner should invest in people and their constant education concerning the materials and spraying techniques. Some of the paint suppliers provide specially designed software, which helps to estimate the materials consumption per every imaginable type of painting job. Train your people, invest in them!
  3. Pure laziness of a painter. Yes, unfortunately it happens often that a painter over-mixes materials merely to avoid going back and forth to the mixing room. To avoid such a behavior, there should be established a good system of the materials consumption and inventory control. In addition, a good working culture in the company should be developed, where every worker cares about the overall result and profitability.

Paint mixing 2

Inappropriate spray gun set up and spraying technique

Another common problem related to the material’s excessive consumption is directly linked to a spray gun used by a painter. I will never stop writing about the importance of a spray gun as single most important piece of equipment in a painter’s arsenal.

What are the reasons for the excessive paint consumption related to a spray gun?

  1. Inappropriate spray gun technology used. For the last two decades the world of automotive refinishing has moved from high pressure spray guns to HVLP and other product saving technologies. However, you could still see in some bodyshops old conventional guns used. Painters just like the atomization, while they ignore that over 60% of the material sprayed never reaches the surface. Use only compliant spray guns with certified transfer efficiency over 65%. Period.
  2. Using wrong nozzle-air cap set up for a spray gun. It is not enough to acquire the newest technology spray gun, but you should also be able to choose the right nozzle size and air cap. For example, using a nozzle size 1.4 mm instead of recommended 1.2mm will definitely increase the quantity of the material sprayed. Consequently, paint defects like “runs” and “color mismatch” will come a long with the higher than expected material usage. Consult your paint supplier and technical data about the correct spray gun set up. Always shoot some paint or just water on a piece of paper to see the size, shape and consistency of the fan produced by the spray gun. Calibrate your weapon!
  3. Poor working condition of a spray gun. Even if you have the right settings and the last technology spraying equipment, proper maintenance and cleaning remain crucial for the economy of the paint or clear sprayed. We should not forget to replace the worn out nozzles and needles. Everyday cleaning is a must.
  4. Incorrect spraying techniques. Provided that your spray gun is in perfect shape, still you can increase the waste of the materials by adopting wrong spraying techniques. The most common mistakes are too slow spraying pace and too much overlapping between the passes. Establish some kind of benchmark for the perfect application techniques, learn from your colleagues and tech reps. New spray gun model may require slight technique adjustments. It is like with a car, when you change your old vehicle on some other model, you alter your driving techniques according to the new car you own.

 

To be continued.

  Spraying picture

 

The minimalist guide to HVLP (Compliant) spraying technology.

Without a doubt there have been said or written a lot about the HVLP or Compliant spray guns and their benefits. However, switching simply to new (not so new, you can say) technology is not enough. A sprayer must also alter his spraying techniques.

WHATIS_HVLP

Definition of HVLP and Compliant technology and its benefits.

Let me just name a few of the benefits, which automotive refinishing professionals will enjoy by switching to HVLP or Compliant guns. Yet I would like to clarify the meaning of each technology first. If the term HVLP (High Volume Low Pressure) is pretty well known, the definition of Compliant gun is not so clear. Actually “compliant” means that it complies with some rules, and particularly rules about VOC emission, which require a spray gun used in automotive repair jobs to deliver at least 65% transfer efficiency. The best two examples of “compliant” spraying technology are Trans-Tech ™ system from Devilbiss and RP ™ from SATA. These two brands came up with similar spraying system, which allows achieving desired 65% transfer efficiency while having increased output air pressure in a gun’s cap. Increased output pressure allows better atomization of higher viscosity materials, like, for example, HS clearcoats.

Benefits of switching to HVLP (Compliant) technology.

-          Lower materials consumption. According to the US Environmental Protection Agency (EPT) simply switching from conventional (high pressure) guns to HVLP will improve transfer efficiency, and, hence reduce material costs, from 35% to 49%. (Yes, by using high pressure guns you can waste up to 65% of the paint). However, in order to get close to 65% efficiency, proper spraying techniques must be adopted by a body shop sprayer  (we will talk about it later on in this article).

-          Besides saving on materials costs, by adopting HVLP technology your will be working in safer working conditions and with less damage to environment.

-          Less overspray will prolong spray booth filters life, consequently it will help to decrease overhead costs.

-          Automotive repair professionals, who switched to compliant technology and adopted proper spraying techniques, enjoy higher quality paint jobs.

-          Finally, being conformable with EU regulations or US EPA rules will insure you in case of inspections from the government bodies.

7 ways to alter spraying technique to get maximum out of your new spray gun.

  1. Set up the inlet air pressure exactly per spray gun producer recommendations. Usually the pressure should be in the range within 2-2.5 Bar (29-36 PSI).
  2. Shorten the distance to the surface you spray. The distance must be closer than with conventional high-pressure guns, somewhere around 20cm (8 inch). Distance for car spraying
  3. Adjust your spray gun until you get clean, cigar shaped pattern without overspray on the edges.                                                                               Spray gun pattern
  4. Angle of spraying must be exactly at 90 °
  5. Spraying speed must be constant, without arching and a little slower than with conventional spray gun. Arching spraying
  6. Overlapping should be no less than 50% (usually 75% overlap is required with high pressure gun).
  7. Check how much paint you will need exactly for each job, and mix just enough quantity to avoid waste of materials.

Finally, please have a look at two short videos from Devilbiss and SATA on how to set up and use your spray gun to get maximum performance and cost saving.

  

 

What do a sniper and a car painter have in common?

                                                     
Target

I have to
admit, I like comparing things which are not meant to be compared just for fun.
So, after the blog post “4 things a car painter and a doctor have in common?”,
have a look on what the most skilled killer has in common with a peaceful (well
I suppose in most cases) bodyshop guy. I spent almost five years in the army,
so both professions are very close to me.

                                                                                                               
Refinishing pic

1.      1. 
Both
professionals need an essential tool for their job to be “executed”-  they need a gun! Not just any gun, but a top
gun
! Actually, the better the gun, the quicker the job will be done; less paint
will be sprayed, fewer bullets will be shot.

                                                                    

                        
IMG_3594

2.      

2. Whether
it is a sniper’s rifle or HVLP spray gun, both tools need regular calibration. To
keep equipment ready for action is crucial. Intensive spraying will inevitably
cause fan’s pattern deterioration, while frequent shooting interferes with
rifle’s settings.

                                                                           
IMG_3612

3.      3. 
Ambient
environment parameters like humidity and temperature affect the gun’s
performance. A good sniper must know the current humidity, temperature and wind
speed, because those affect bullet’s trajectory. While a good car painter must
also set his spray gun, according to the weather conditions (it is called
“Intelligent atomisation”
). For example, with high humidity, the atmosphere
slows the drying time of paint, and higher flow air cup (HVLP ) is better to be
used. While, as the temperature increases, drying times of coatings speed up,
so smaller nozzles are preferred for decrease paint flow. 
             

     Intelligent atomisation

4.      4. 
If
you ask a NAVY SEAL, what is the most important thing before and after the
operation, he would probably reply: taking care of his gun is an absolute
priority. Similarly, car sprayer will spend enough time to keep his favorite
Devilbiss or SATA (or any other brand) gun clean and shiny.

                  

                                                                                                         
IMG_3633

5.      
5. It
is not a secret that the best collision repair job is the one, which is not
visible, as if no repair was done what so ever. Alike, a sniper will leave no
traces on his ambush. No traces, no shells, absolutely nothing.

                 
Sniper 3

Despite the
similarities, I have to admit that there is one big difference between a sniper
and a car painter: the first is trained to kill, while the second is trained to
save…even if he just saves your car’s look
🙂



                                                                                                      
Doctor doll

 

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