High Gloss Films have been considered the most difficult film to press using a membrane press and even more difficult to press with a vacuum press. This article will discuss the nature of this surface and give useful advice.
Earlier in my career I worked for a leading Japanese manufacturer of 3D Laminates and I worked as their technical guru to help companies press High Gloss. I must admit that at times I wanted to just give up but the finished products were so unique and special that I persisted.
A lot of companies in Europe who press High Gloss do so with a Fritz Bladder press that uses a hot liquid in the bladder to press the doors. The bladder presses have great pressure and they distribute the heat evenly. The bladder presses though are not really promoted and the most common membrane presses simply use air to push their membranes. Unless you intend to buy a press just for your High Gloss I would recommend using your existing press and working with the parameters to get the best results you can.
The most common problems with High Gloss are wrinkling, orange peel and telegraphing. Typical High Gloss Foils are 0.7mm thick or 28 mil and they are made using an Extruder rather than a Calender. This thicker guage of PVC requires more exposure to heat but with too high heat it will inevitably cause wrinkles in the finished part. Therefore it is recommend to press using a lower temperature such as 105 Celcius versus 118 Celcius for an average woodgrain. The preheat however, should be increased to 60 seconds or even 90 or 120 seconds rather than an average of 30 to 45 seconds for a 12 mil solid or woodgrain. As a rule of thumb, the above two settings are the biggest difference between pressing a High Gloss and a Solid or Woodgrain.
Another trick is to space your parts out a bit farther than normal from each other. What this does is to give more material and it requires less stretching of the material. Its common sense but the closer your parts are with this thicker material then the more the material has to stretch to get down on the edges.
If you encounter wrinkles then you will most likely need to decrease your preheat slightly or possibly even your temperature by a few degrees. There is a small window of settings that will get your High Gloss to press.
If you encounter orange peel in your parts you may want to reduce your preheat time and potentially even the pressure slightly. The orange peel is equivalent to small islands of built up heat if that makes any since. When you press High Gloss you really want to have the least amount of temperature for the least amount of time as possible. Some companies are very light on their application of glue to the center of the door component to reduce the glue/heat reaction that can cause orange peel. If your doors are sprayed thoroughly on the edges then you should not have any delamination issues.
In terms of pressure, I have have heard of different theories such as using less pressure however in Europe many companies have presses that will go above the 4 or 5 bars that a US press has. I have heard of 7 bar and up presses being used for pressing High Gloss doors however I have never personally worked with one of these machines.
If you encounter telegraphing when pressing your parts then you may need to sand your parts to get a more smooth texture before applying the glue. If you are encountering small dust particles then you may need to look at a few things. Is your roll rack grounded? If not then the static electricity could be pulling particles up onto your roll. Is your press in the same room as your router? If so you may need to think of your next investment being into building a special room for the press. Just a room to keep the dust out is adequate so you could use framing and clear plastic. Another common trick is to put a fan on top of your press to direct particles away from the press. This will decrease the small particles showing up under the door.
Most High Gloss films come with a masking film. In addition to having more rejects, High Gloss is more succeptible to scratches during installation. In the past there have been problems with some masking films being difficult to pull off. Most manufacturers have made improvements in this area so the film will come off more easily.
The gloss level of a High Gloss film ranges from 70 to 100 degree sheen. Dackor offers a Semi Gloss foil that has a 55 degree sheen. This semi gloss product does not have the mirror finish that a High Gloss does but instead has a slight stipple to it that is very subtle. This in affect hides telegraphing, scratches and debris from showing up. The product is also a 16 mil so it presses more easily and costs less than a High Gloss film. The appearance of the semi gloss film gives the look of a semi gloss paint that is shiny and looks as if it has been sprayed on.
In summation, High Gloss and Semi Gloss films are an attractive surface finish that give Kitchen doors a clean and modern look. With the right settings you can successfully offer either finish to your customers. Semi Gloss films press just like any other 16 mil film but if you should have trouble pressing the 28 mil High Gloss films you can call or email me and I will be glad to help with your settings.
Properly manufactured Thermofoil doors will not delaminate without exposure to heat. To determine if a door has a good bond and the glue line was activated simply pull a part from production and do a pull test. In a pull test you cut a triangle shaped amount and pull the vinyl off the corner of the door. If the bond is good you will notice that there will be fibers on the film and also it will be very difficult to pull off the vinyl as pliers will need to be used.
If you are pulling heavy fibers then you almost certainly will pass heat tests. If you are not pulling heavy fibers you may need to give extra spray to the sides of the door or increase heat or preheat to give total heat exposure to fully bond the glue line.
So what about heat delamination?
The two most common places of delamination from heat are directly above a tea kettle or beside a self cleaning oven. Keep in mind that these temperatures are so hot that they will strip lacquer off wood doors too however with thermofoil its more noticeable because the vinyl will actually shrink and will expose the MDF. This is not a defect in the door. Tea kettles should be pulled out from under the upper cabinets and the doors should be hinged away from the oven during self cleaning mode with the doors open and drawers open during self cleaning operation. One other helpful tip is to have your cabinet manufacturer use a heat shield next to ovens.
As a thermofoil door manufacturer how do you test your heat resistance?
Firstly, a 1 part glues resistance is typically 150 to 175 degrees F and for a 2 part glue 170 to 200 degrees. Simply heat an oven up to 150F for one hour and then raise the temperature by 5 degrees until failure or delamination occurs. You will notice the delamination as the vinyl will pull up revealing the mdf. If your oven doesn't go that low simply utilize a digital thermometer and run the cord beside the part. Heat your oven on low and crack the door if necessary to keep the temp at 150 and raise at intervals to get the highest temp reached before delamination occurred. You may also use heat strips on your test to ensure accuracy of the highest temp reached.
The proper machine to professionally test is a Blue M lab heat test machine however they are quite expensive. One other tip is to ask your glue supplier to run a heat test on your parts.
I hope that this information is useful and remember that the most important thing is to purchase your components from a reliable producer in which you have a good relationship.
Whether it's a single part or two part glue it is important to have enough glue on the edge.
What you are looking for is a 90% sheen after the glue dries so that you are sure to get a strong bond. The visual appearance of this sheen signifies that the board did not soak up all the glue and that there is enough on the outside to bond to the laminate.
The next area of importance is to make sure that you have gotten the glue line hot enough to bond and the activation temp can be obtained from your glue supplier. In addition, you must have the time long enough for the bond to take place with the 3D Laminate.
It is very important to not try and save on glue and to try and run to fast that the glue does not have time to set. This will ensure happy customers who will keep ordering. The key is to also pull parts at times and to do pull tests. A pull test is achieved by cutting a triangle of vinyl and pulling it off the doors edge. This will show you how much fiber is being pulled and also how difficult it is to pull off.
When it comes to glue, its not a place to try and save money as its the key behind quality components !
Pressing 3D Laminates and Blow outs
There are many different tips and tricks to pressing. Often I am asked for formulas however I often find that each company may require different settings based upon the material they are pressing, the profiles, glue type, stage height and so on. One common issue that all companies have or will eventually face are blow outs. During the press cycle you can hear a blow out occur by a pop and a hissing sound. After retrieving the tray from the press you will typically find that dreaded hole and all the parts did not form properly because the press lost its seal.
Blow outs are typically caused by either too high of a heat versus too low heat. You can tell them apart because blowouts by too low heat are more like tears and blow outs by too much heat are typically circles or tear shaped holes that seem uniform.
Keep in mind that raising or lowering the temperature alone may not solve a cold or hot spot issue. Imagine if you raise the temp but get heat issues but lower the temp and get lack of forming.... Other issues may be at play such as having too short of a preheat. If your preheat is too short then it may be possible that the heat did not have time to soak or penetrate the entire thickness of the 3D Laminate.
There are different scenarios where cold spots can form such as using thicker films in a 16 mil to 20 mil where the heat has not soaked all the way through the thickness of the product. Imagine if you are using a very dark color like a Wenge which is almost black and it conducts or absorbs the heat more rapidly however you get cold spots blow outs. Then when you raise the heat you get hot blow outs. The solution to this type of problem can be to do a longer preheat but keeping the temp low enough so that you do not over heat any one particular area of the material. You may also want to use heat strips to ensure you are getting heat distributed uniformly in the press.
With membranes on a Shaw Almex, Wemhoner or Italpress for example you may experience less blowouts because the membrane is the source of pressure and that pressure keeps the blowout from occuring. With an Italpresse with no membrane (for example) that inflates the vinyl to the upper platen you get a balloon where the center of the material is touching the platen and heating up very rapidly however the outer portions may not be heating as rapidly and you can actually experience cold spot blow outs towards the outer perimeter of the press. There are two solutions for this type of problem. The first is to have a longer preheat but at a lower temperature so that you get all the material uniformly pliable but not one portion of the film is so hot that it is weakened. There are some machines in which you can reduce the inflation time and then preheat part of the time with it inflated and then preheat part of the time while its not infated. You may need to contact your machine supplier to ensure that your particular model has this option.
Another scenario with blow outs can be caused by utilizing the Eco Jig pin system manufactured by Dackor. This pin system is an affordable alternative to automatic systems (although not as efficient as an auto system). In the Eco Jig system you must ensure that the pins are pushed under far enough so as not to create a penetration point for the vinyl to hit. By pushing the pins under further it creates an even distribution of pressing at the bottoms of the doors and will stop blowing out under this situation.
In summary, there are many variables which can cause blowouts based upon settings.
Step 1: Determine if are having cold or hot blow outs
Step 2: If raising or lowering temp does not help then try working with your preheat
Step 3: If the above does not work email your settings, machine details and problems you are having to email@example.com
I hope that this article was helpful, be sure to contact us for further assistance.
Whitening on the corners of 3D Laminate thermofoil doors
There are many different tips and tricks to pressing. Often I am asked for formulas however I often find that each company may require different settings based upon the material they are pressing, the profiles, glue type, stage height and so on. One common issue that all companies have or will eventually face are whitening on the corners.
There are many misconceptions about what causes whitening on the corners and typically the laminate is blamed for the issue. Although the laminate can be a reason it is not necessarily the culprit. Read more to delve into the issues and the solutions on whitened corners on the doors.
First I'd like to separate lightening from whitening. I define lightened corners as separations between the print layer and the base film layer and whitened corners as separations between the top cap and the print layer. When you see a corner that is lightened it is typically revealing the base layer of the foil. One over generalization is that a lighter backer of the foil is the issue. When thermofoils are produced typically the lighter backer is used as the base tone of the design. Quality manufacturers have dozens of backers whereas a low end manufacturer may have only a few bases to choose or may use a white backer on a dark woodgrain for example. But most common you will find mustard , almond or chocolate backers on most woodgrains and if any foil is over formed it will reveal the base layer and therefore have whitened or lightened corners.
Another common mistake is that you can bend a sample and when it whitens that is evidence that the material will whiten when pressing. When you bend a thermofoil sample and it whitens it typically is forcing the top layer away from the base layer and this is very common among quality manufacturers and will not necessarily cause whitening on the edges when pressing. It in fact shows how they produce their film in respect to the printing layers whether direct printed, reverse printed or at what temperature the material was laminated at. In fact, many high end manufacturers darker colors will whiten when you bend them. So if a sales person grins and bends his sample to show that it doesn't whiten they are trying to show their product is of a higher quality but it is really just a bi-product of how they produce their product or may even show that their company doesn't even have the capability to produce by direct print with a finished top cap. They may actually be showing a weakness of their product and not even knowing it. By bending a sample it will not necessarily stop whitening on the corners when membrane pressing. In the application of miter folding PVC bending the sample does in fact have a direct correlation to whitening issues because the part will be bent at a lower temp whereas in membrane pressing the part is formed at full temp.
Want to know how to tell the difference between a top cap separation and a print layer separation?.... The key way to tell is if your parts lighten to a clear or bluish edge or if they whitened to the color of the base of the film. If they whiten to the base of the film then its not caused by the top layer separating. If the corner of the door is in fact bluish or clear in tone you can test it by rubbing it with a block of wood or flaring it with a heat gun. In a miter folding application of a thermofoil a wooden block or heat gun can be used to reseal the top cap to the whitened area. In a membrane pressing application the key will typically be to use a higher heat so that it soaks through the foil and does not cause a separation between a top cap and a print layer.
The most common problem with lightened corners are caused by either too much or too little heat. With too much heat you will over stretch the material and will typically find the outer doors that do not have jigs or are not on the edge of the table. The material is heated up too high and then there is no jig or tray filler to capture material and then the laminate may get over stretched on the corners. A simple solution is to put a jig / tray filler close to the edge.
Another common problem with lightened corners are caused by too little heat. When the material is too soft or has cold spots on the table the material can separate on the print in the areas where it is being stretched the most which is typically the edge or corners of the doors. You can put a heat strip in various places on the press to find any cold or hot spots in your table.
For darker colors such as a Wenge which has ticking you may also find that these darker colors are more likely to have too much heat applied to fast. What I mean is that the dark woodgrains are likely to absorb heat faster than a lighter woodgrain and especially when using bulb heating elements. In addition if the foil has aggressive ticking you may find that these deep ticks become separation starters. So the material pulls apart faster between the ticks. The solution for this is to move a jig / table filler closer to that edge and it should solve the problem right away.
In general most press operators think in terms of board feed rate in their saws or imput data into the press machine but we often have to think of membrane pressing as more of an art. To recap,
1. Whitened corners can be due to the material being too hot. Solution: Put fillers closer to the edge of the part
2. Whitened corners can be due to the material being too cold. Solution: Increase the preheat by 10%. Be sure to use heat strips to ascertain this
3. Dark woodgrains or items with deep texture can whiten easier. Solution: Put fillers closer to the edge of the part
I hope that you find this post helpful and if you would like to add any tips or points please feel free to send me an email.
Drying Racks for 3D Laminate components
Recently I received a call from a company who just got a press. They said they were looking for drying racks and that when asking around people recommend that they call me. I was so happy to hear this because it signifies that people know I will go the extra mile and if I dont know the answer I'll find it out. So I looked through my notes and right away found the following site which sells carts for drying thermofoil doors and other components.
Cost $325 for Drying Tower DT-50. 50 shelves 25 per side
This is the price the last I checked however it may change by the time you read this post.
If you are ever looking for something or need pressing assistance please dont hesitate to ask. Also if its a topic or product that you do not want me to publish on this blog you can also request that as well.
Dackor does sell tools at www.dackor.com/tools however we do not currently carry drying racks
Producing Shaker doors that are clean and neat are the goal. If you take a 3D Laminate shaker door and cut it open you may be surprised to find a plant in center panel. Read below to learn more.
PRODUCING A SHAKER DOOR:
To produce a shaker door and then membrane or vacuum press the door companies first router out the center reveal. One common issue is that in doing so the fibers of the door open up. It can be very difficult to then get a sander in and to accomplish the desired finish. On top of that , when a PUD adhesive is applie, the PUD adhesive is about 58% water which further opens the pours of the MDF open and will show through the 3D Laminate after pressing.
The ideal solution is to take a 1/8" HDF board cut to the size of the center panel and to drop it into the center of the shaker. This is the most common way companies create good looking shaker doors in the component industry. The HDF (High Density Fiberboard) can be left unsanded with the factory finish. It is important however to glue the center panel in because failure to do so will make it sound like the beat of a drum when closing the cabinet door. The center of the door can be glued in by the PUD adhesive used in the membrane pressing process.
For painted doors, the key to get a good finish is to paint the door and then sand it to a 250 to 300 grit and then paint again. This will smooth out the surface before doing a finishing coat.
PLANT ON SHAKER:
For plant on Shaker, you can take 1/2" mdf and run a 1/4" to 1/4" mdf through a shaper and then miter cut and piece the parts on the door using a PUR adhesive. This reduces the milling time out of the shaker and creates a lower processed cost Shaker. It will have a reveal line on the perimeter of the door however this is a small price to pay for saved CNC milling time.
If you follow the steps above you can get a better looking shaker door. For additional information please feel free to contact me for further information or further research.
There are various ways to process 3D Laminates. In this article I will mention all the ways you can process 3D Laminates and also mention some common machine names used in membrane pressing and vacuum pressing.
At the time of me writing this article, the most common brands of membrane presses in North America are Wemhoner which is sold by Stiles Machinery, Shaw Almex which is sold by Black Brothers, Italpress which has their own office, Orma, and Burkle. www.membranepress.com
Advantages of membrane presses: Membrane presses typically use rubber or silicone membranes to firstly transfer heat to the components more rapidly and secondly they apply positive pressure on top of the components to press the material while the vacuum on the bottom of the press can also have suction. The pros are that the cycle times are fast and its easier to get more detail in the component under most conditions. The cons are that they membranes need to be replaced periodically depending upon the cycles ran and also based upon the parts produced. The other con would be the cost of a membrane press. They typically cost $200K to over $500K however you may find one for less or a used one. Please do keep in mind that some membrane presses are capable of removing the membrane from the machine and still operating but not all.
VACUUM PRESSES:The most common brands of vacuum presses sold in North America are Shaw Almex, Italpress and Greco. If you are a maker of vacuum presses and do not see your company's info here please contact me. I apologize if I overlooked it.
Advantages of vacuum presses: Vacuum presses are more affordable however they do not have positive pressure on top. Vacuum presses rely solely on the vacuum power below and they use light bulbs or heat plates on top in some machines. Most vacuum presses have longer press cycle times and do not get as much detail into the components. There are some tricks such as drilling holes in the backs of the components to enable vacuum to pull through the MDF and also some companies will score the glue line on the side of the component with a knife which breaks the seal a bit and enables more vacuum. In general, companies who produce mass components for others prefer a positive pressure membrane press with or without the membrane in lieu of a vacuum press. Vacuum presses are an inexpensive way to get in the business however they are more suited for companies who use the components internally for their own cabinets or fixtures and less suitable for companies who mass produce components for others and whose livelihood is attached to selling components due to the longer press cycle times.
3D Laminates or vinyls can also be flat laminated either by a flat lamination machine utilizing PUR adhesive typically. These machines are designed for fast flat lamination. The other way to flat laminate is by a nip roller using a 2 part epoxy glue.
3D Laminates can also be processed by profile wrapping moldings
Miter folding is where material is flat laminated or membrane pressed to a component with a v groove in the back of the part. A line of glue can be ran in the groove and then the part is simply folded to create a seamless fold. The vinyl acts as a hinge. Please note that white lines can appear on the fold with vinyls which is caused by various reasons. Companies use wooden blocks to rub or heat guns to remove the white lines. Some laminate manufacturers can produce vinyl so that they will not whiten when folded.
3D Laminates can be processed by contact cement, peel stick or laminate backed for hand applications. The laminates are not specifically made for this type application so this is the exception rather than the rule.
This post is just a teaser and does not get deep into the topics. If your company is a processor in North America and has technical questions you can contact me for more detailed information, tips and tricks.
Manufacturers of 3D Laminates know that the product has many advantages as compared with HPL and other surfaces. 3DL's impact resistance can be far superior to most laminate surfaces and the taber abrasion can be extremely high especially with solid colors whitch are homogeneous. But how about scratch resistance? In this article I'd like to discuss some obscure tricks on how scratch resistance is obtained with 3DL that most companies don't share.
Firstly, each company has claims that their product is more durable based upon a unique or proprietary lacquer. Although each company has its own formulation the real secret is in tweaking a combination of lacquer and texture. Also gloss level of the print layer and lacquers can play a roll as well as the color of the print however this article is meant to focus on a specific subject of texture which is one of the biggest factors that contribute to scratch resistance of 3DL.
OK... so to start....
The most common lacquers are polyurethanes or polyurethane combinations. Applying lacquer is key to protect the top surface's hills and valleys and provide hardness to the surface. This sounds like the end all be all solution however in reality if a sharp objects digs into the peaks (hill tops of the texture) in a certain way then its irrelevant as to how much or what type top coat is applied. Think of your carpet and running your foot over the carpet. The carpet is not damaged however you moved the carpet strands in a different direction it gives the appearance of difference and that is at the basis of what a surface scratch really is. So if you think about it, a micro level, scratches to most surfaces are either a displacing or a removing of surface area. In theory a top coat will protect a scratch from occurring however in practice its only one component to creating a scratch resistant surface.
In general a higher texture combined with lacquer is a way to get an overall scratch resistant surface. Some woodgrain designs, for example may have a lighter texture from one supplier due to market demand and when you try to scratch it, the appearance is that that supplier's product is less scratch resistant however upon closer inspection you may find that if they put the same texture on they would get equal scratch performance. So its very difficult to judge scratch resistance between supplier if you are not measuring apples to apples. Since each supplier uses different textures and different lacquer/gloss level combos it also may impact the scratch resistance performance in that single color.
Another point is in the texture layout. Imagine a texture on a microscopic level and when a sharp object moves in a straight line it is removing hills on the tops of the texture. If the texture is spaced in a certain way to make the hill tops more random it can trick the eye into not seeing the scratches as easily. This can also be achieved by making different heights of texture in the emboss. Imagine at certain pressure points only knocking off a certain height of textures however with just slight more pressure it may finally break into the next layer of texture hills. Its another clever way to enable an object to glide across the top of the texture yet not see the scratch as easily with the naked eye. Surprised by this observation? As with any product, the expertise in product design combined with the marketability of its appearance all come into play in order to achieve a result. You may in fact, start to see all the complexity that goes into creating a 3DL.
You will also notice that dark colors show scratches more easily. Lighter colors absorb the light and blind your eyes to the scratches that are on the surface so to speak.
So, in conclusion, there are a variety of ways to make a scratch resistant 3DL... Lacquer, quantity of texture, color of design and texture layout on the microscopic level. The items just mentioned must also be used in proper combos to create the best affect.
One potential problem in pressing is called ghosting or shadowing. This is where the center of the part seems to have a darker section or where it looks different than the edges of the part.
This type of manufacturing defect can be fixed by adjusting the settings and is not a vinyl or glue issue.Essentially ghosting is caused by a change in the surface texture. This is caused by the vinyl becoming over stretched on the edges and the center part of the component which is discolored is a section of the vinyl that was not stretched at the same rate as the other areas.
Typically this issue only happens on membrane presses and not on vacuum presses. The reason is that the membrane is trapping the vinyl down to the door. Raising the membrane for a vac to get the vinyl stretching evenly then lowering the membrane to finish up the detail. Various presses have different functions so this needs to be discussed. In cases where your membrane press does not have the ability to raise the membrane for a vac stage you can try to move the parts further from each other. This gives more vinyl between each component and can reduce the over stretching.
If both cases above do not work please feel free to contact your laminate sales rep and they will get a tech expert to help fix the issue. It can be solved.
Color inspiration from around the world, backstories on design inspiration and informative articles about marketing, membrane pressing and personal development. Author Mark Viers delivers fresh content that will help you and your business grow and thrive.