Question 1

Does MicroCare Have Competitive Stencil Roll Pricing?

Accepted Answer

There are a number of tricks companies can use to lower stencil roll and wipe prices. You think you’re getting a better deal, but really you’re getting ripped off because you pay for cheap rolls with higher consumables costs, extra rework, impaired throughput and reduced yields. Some tricks are obvious, some are pretty subtle. Be sure you get what you think you are buying.

Watch out for the following tricks and gimmicks:

Off-Brand Paper

This opens a number of questions about reliability. For the best results, only high-quality, hydroentanged fabric from reputable manufacturers should be used, such as the Sontara™ papers from DuPont which is highly recommended by the stencil printer manufacturers. MicroCare strongly recommends customers stick to the good quality paper. The MicroWipe™ FP stencil rolls are made with fabric, not paper, for even better results.

Papers Containing Glues

Normal paper consists of cellulose fibers bound together with glue. Some ultra-cheap stencil rolls are made in the same way, with paper made from polyester fibers and glue. This makes for a really cheap roll, but not a quality roll. This is because the solvents used in stencil wiping dissolve the glue, and at the microscopic level residues are left behind and the paper is weakened, increasing linting. As a general rule, stick with hydroentangled papers for the best printing results. The microphotograph, right, of a cheap stencil roll paper shows the internal spaces, between the fibers, filled with glue. This makes the paper cheaper but decreases it’s ability to pick up contamination.

Using Paper “Seconds”

“Seconds” are rolls of paper which did not meet the manufacturer’s quality standards, so they dump the paper at a discount. Of course, you don’t know why the paper failed the QC test, so it’s a hard to know exactly what the paper will do once it’s on the stencil printer.

Shorter Rolls

MicroCare has documented instances of rolls priced substantially less than MicroCare rolls, only to find there was substantially less paper on the roll. Caveat emptor, we say. (By the way, there is some natural variation in the thickness of the paper, so the exact length of each roll will vary slightly. The most critical parameter actually is not length, but the outer diameter of the roll.)

Only MicroCare offers our unconditional guarantee of quality on every roll we sell because our unique MicroWipe™ FP paper will lower your stencil printing costs. Our prices are competitive; but not cheap. Buy cheap and who knows what you will get.

Question 2

How Does the Vacuum Feature Affect My Paper Choice?

Accepted Answer

The vacuum feature on your stencil printing machine improves the quality of the printing process because it sucks excess solder paste out of the apertures. This means fewer misprinted boards, fewer rejects, fewer change-outs and less downtime, all of which result in more boards per hour. However, if the cleaning paper is not sufficiently porous the vacuum feature will not be effectively remove the paste from of the apertures and print quality will suffer.

To make the vacuum process work, you need a paper that is more porous than the original stencil wiping paper. If you tried old-style rolls on a vacuum system, the vacuum would not be able to pull enough air through the paper to operate effectively. So a more porous and open paper was required.

Today MicroCare offers a special vacuum paper for all of the major printing systems, including DEK, EKRA, Panasonic, MPM and others. The MicroWipe™ FP fabric is specifically engineered for fine-pitch stencil work. This fabric also works extremely well on vacuum systems. We strongly recommend you consider the MicroWipe™ FP paper which will work better than anything else on the market today.

The understencil wiping roll, installed on an MPM UP2000 printer

Question 3

Does the Paper Quality on a Stencil Roll Make a Difference?

Accepted Answer

The short answer is, YES, the quality of the understencil wiping roll make a BIG difference. It is a challenge to produce today's demanding electronics on high speed, automatic production lines. Sometimes the smallest detail will derail the production process and devastate your productivity. One of the most common show-stoppers we have seen is improper stencil printing.

“First” Quality Paper

Stencil rolls made by MicroCare normally feature “first” quality hydroentangled paper. Other people may use quality fabric, or maybe not. Or they may buy rejected “seconds” from a vendor and claim it is just as good. Or maybe they just buy cheap paper from around the world (often, China) and let you find out for yourself what works and what doesn’t. Here’s a good rule: caveat emptor: buyer beware. If a price sounds too good to be true, it probably isn’t!

More Prints Per Roll

Stencil rolls from MicroCare can clean stencils dry, without IPA alcohol or other solvents. This means the “indexing” of the stencil roll can be reduced to the printer’s minimum, usually just a few millimeters. This can extend roll life 100-300%, depending upon the printer and the roll being replaced.

Lower Fiber Counts and Less Linting

MicroCare rolls will contain fewer broken fibers, resulting in less visible contamination 100µ or larger on your stencils and boards. The binders (glues) used in other nonwoven papers tend to abrade out of and away from the fabric, yielding higher particle counts in the 0.5µ range or higher.

Less Ionic Contamination

MicroCare SMT rolls do not contain any ionic contamination which could be released and re-deposited on the stencil and boards. Fabrics not manufactured by MicroCare often have higher extractables, almost always sodium chloride and other corrosive additives. These are released when solvents come in contact with the paper. When it comes to electronics and stencil printing, this is not good.

Reduced Non-Volatile Residues

Binders (the glues in paper) often leave white residues. Sometimes these are misdiagnosed as problems with the solder paste or solvents. Isopropyl alcohol, the industry’s most popular solvent, is a common ingredient in solder paste. In addition, many stencil printing systems spray solvents onto the paper during the wiping process. Often these extractables can be up to 1% of the weight of the sheet — nearly two grams per standard 450mm/18-inch stencil roll.

Greater Durability

Once the binders are dissolved by the solvent, the strength of the paper deteriorates. In contrast, laboratory tests prove that MicroCare stencil rolls are almost completely unaffected by electronics-grade solvents. Micro•Wipe™ FP stencil rolls exhibit a tensile strength of up to 400N/90 lbs., depending upon the fabric, and will retain 75% of this strength even when wet.

Greater Consistency

Since there are no nonvolatile binders, nor other chemicals, adhesives, or surface finishes added to the paper during the manufacturing process, the fabric is more consistent from lot to lot, and the wiping process will be more reliable.

Greater Absorption

Binders fill the gaps between the fibers in the fabric, clogging spaces that would otherwise absorb solvents, solder paste and epoxies. MicroCare papers lead the industry in purity, puffiness and softness.

No Unexpected Reactions

Some papers use binders which are not miscible with the solvents in the solder paste. This will cause the solder paste to move away from the paper, rather that to be absorbed by it, and creates a Fisheye effect during the wiping process.

Improved Hypoallergenic Properties

Lacking glues or binders, MicroCare fabrics and papers does not exhibit allergic or toxic responses when in contact with skin. In fact, the material is so clean it is used in hospital operating rooms.

The understencil wiping roll, installed on an MPM UP2000 printer

Question 4

What Are the Benefits of Choosing MicroWipe™ FP Paper Over Ordinary Stencil Rolls?

Accepted Answer

MicroWipe™ FP stencil rolls from MicroCare will reduce your stencil printing costs, improve yield and speed throughput. Here’s how:

The standard stencil printing procedure involves wetting the stencil roll with solvent before the cleaning cycle. But the solvent contaminates the solder paste, which reduces yields. Stronger and more absorbent papers can clean stencils without using solvents. This saves time, money and improves yield.

The differences can be huge. Here are some specifics about the benefits of MicroWipe™ FP rolls:

Less Cleaning, More Printing

FP stencil rolls reduce the number of time-wasting cleaning cycles. Each cleaning cycle avoided MicroWipe FP stencil rolls creates time for five printing cycles (~30 secs. vs. ~150 secs.). In addition, since the cleaning cycles are more effective there are fewer stoppages for manual stencil wiping. This produces stunning improvements in productivity. At a major PCB subcontractor, MicroWipe™ FP rolls helped engineers move from 14 minutes of cleaning cycles per hour to nine minutes per hour. Overall, MicroWipe™ FP rolls boosted hourly production from 32 to 55 boards – a 60% increase in productivity.

Eliminate Solvents

MicroWipe™ FP rolls can, in many (but not all) applications eliminate the need to wet the paper with solvents. This results in improved yield and reduced defects. It turns out that the solvents contaminate the solder paste on the stencil. The solvent can dilute the solder paste, resulting in slumping and shorts. The solvent also weakens ordinary stencil rolls, increasing linting and misprints. Get rid of the solvents and you get rid of all these problems. This is the single most important benefit of switching toMicroWipe™ FP rolls.

Stronger Solder Joints

A cleaner stencil allows more paste to flow onto the board, resulting in taller solder pads and stronger solder joints. In one prolonged test, Micro•Wipe FP rolls increased pad height an average of 11%. More solder means stronger joints.

Fewer Defects and Misprints

Defective printing is a huge waste of time and money. In a large-scale trial with five SMT lines the switch to MicroWipe™ FP rolls improved the defect-free yield up to 99.55% from an average of 97.25% — an 83% reduction in defects.

Reduced Indexing Extends Roll Life

There is no argument that MicroWipe™ FP rolls are more expensive than standard rolls. But MicroWipe™ FP rolls last longer because cleaning is less frequent, which saves money. Since the rolls are used dry, not wet, the indexing of the roll can be reduced to the printer’s minimum. This saves enormous amounts of stencil roll fabric. These rolls also minimize the cost of solvents and other consumables.

In short, the cost savings, productivity gains and quality improvements allow companies using Micro•Wipe FP rolls to cut their total printing costs significantly.

Standard understencil wiping rolls are used with solvent. The roll must be “indexed” several centimeters after each cleaning. Wiping dry means the indexing can be greatly reduced, which makes rolls last longer and saves money.

Question 5

What Is MicroWipe™ FP Stencil Wiping Paper?

Accepted Answer

Micro•Wipe™ stencil rolls from MicroCare have been the industry’s leading stencil cleaning roll. Now, the best has gotten better with Micro•Wipe™ FP stencil cleaning fabric.

At a microscopic scale, an SMT stencil looks like thousands of tiny razor blades. Those sharp edges shred old-style stencil wipes, causing defects and rework. Tough, durable MicroWipe FP fabric minimizes this problem.

This fabric — not paper! — has been engineered from the ground up and optimized for fine-pitch stencils and lead-free solder pastes. This new technology increases through-put while reducing defect rates. Today, more than ever, MicroWipe FP rolls are the smart choice for cleaning stencils. The single most important difference is that this new fabric is so strong and cleans so well the stencil can be wiped dry, without using solvents. This saves money, improves yield, and extends roll life. This is a unique benefit available only from MicroCare.

Not All Papers Are Created Equal

The 'FP' fabric itself is different from traditional stencil roll paper. Let's take a look at the differences:

Obj- Paper.Binders.Endview.300x.350x290.RGB.96dpi

Photo, right: Inexpensive stencil rolls normally are made of polyester fibers bonded together with glues. These glues fill the empty space in the paper between the fibers, limiting the amount of solder paste the wipes can scoop up. In addition, the fibers themselves are feeble and prone to shredding. Glue clogs the interior spaces of these cheap stencil roll paper, so the paper can’t pick up as much solder paste as one might hope.

Cross section of fibers in paper used for stencil cleaning.

Photo, right: More expensive paper, such as the classic Sontara® material, are based on a “sandwich” of hydroentangled mix of cellulose and polyester. The cellulose absorbs the solvent and solder paste while the polyester provides strength, and the two fabrics are bonded together without glues or binders. This is not a bad paper. But the cellulose tends to shred, which decreases throughput and quality.

Cross section of fibers in paper used for stencil cleaning

Photo, right: In contrast, MicroWipe™ FP fabric is a hydroentagled mesh of durable, absorbent, pure, synthetic fiber. The individual fibers are extremely long, hard (uncrushable), clean and lint-free. All of this reduces linting, improves paste pick-up, and enhances absorbency. This improves the results from each cleaning cycle. In effect, each fiber becomes a tiny squeegee, scraping the solder paste off the stencil. Each fiber is exactly the same as every other, and no glues are used in the paper. These strong fibers pick up solder paste better than any other fiber tested.

Detailed field trials have proven that Micro•Wipe rolls made with MicroWipe™ FP will reduce defect rates and cut production costs while boosting quality. In development for nearly three years, it was subjected to dozens of grueling field trials. Importantly, every customer who conducted a proper test and has tried the Micro•Wipe™ FP fabric agrees the new material cleans better and improves yields.

More Expensive to Buy, But Lots Cheaper to Use

MicroWipe™ FP rolls help produce boards at a lower cost. They reduce the number of time-consuming cleaning cycles, by improving the cleaning during each cycle so companies clean less often. Each cleaning cycle eliminated creates time for approximately five printing cycles (~30 secs. vs. ~150 secs.). If the stencil printer is the bottleneck in your facility, this can produce stunning improvements in throughput. At a major PCB subcontractor using DEK stencil printers, Micro•Wipe™ FP rolls pushed production from 36 to 55 boards per hour – a 60% increase in productivity.

Another improvement results from better, cleaner apertures. A cleaner aperture allows more paste to flow onto the board, resulting in taller solder pads and improved solder joints. In one prolonged test, Micro•Wipe™ FP rolls increased maximum pad height an average of 11%.

Misprints and yield improvements are another area in which Micro•Wipe™ FP technology pays off. One large-scale trial used five SMT lines with DEK printers and Indium 92J solder paste. With Micro•Wipe™ FP rolls, the defect-free through-put jumped to 99.55% from an average of 97.25% — an 83% reduction in defects. All of these improvements makes Micro•Wipe™ FP rolls very cost-effective.

All of the MicroWipe products are available in every popular configuration, with all the different widths, lengths, diameters, cores, and extensions users require. Customized designs are also available, for customers needing large quantities of specialty rolls. For details on the FP rolls or custom roll options, call or email MicroCare tech support. We’ll get you a stencil roll that meets your needs and your budget.

Question 6

Can I Get Stencil Wiping Rolls in Custom Sizes?

Accepted Answer

While most companies shy away from doing custom work, MicroCare finds it easy. We offer 200+ configurations of custom rolls, and we’re adding more all the time.

Custom rolls are useful because they eliminate wasted paper, they minimize solid waste going to landfills, and if they are properly implemented can improve the quality of the wiping process. All of this is good!

You should be aware, however, that custom rolls tend to be more expensive than standard rolls, even if there is less paper on the roll. It’s a manufacturing thing. Sorry.

For details on the custom roll options, contact MicroCare tech support. We’ll see if we can find a current roll that meets your needs, and if not we’ll see if we can cost-effectively get you a custom roll.

Stencil rolls from MicroCare come in over 200 sizes and configurations

Question 7

Can I Get Stencil Wiping Rolls from MicroCare?

Accepted Answer

Absolutely. MicroCare offers a full line of standard, OEM-compatible wiping rolls. MicroCare offers stencil rolls for every popular make and model of stencil printer. These will fit the MPM/Speedline family of printers, plus Ekra, DEK, Panasonic, Fuji and others. If you have an unusual machine, we would be pleased to develop a roll that will fit it. MicroCare features the MicroWipe™ FP paper for fine-pitch stencils. MicroWipe™ FP paper is available exclusively through MicroCare.

Other paper and wiping products from MicroCare include a full line of presaturated wipes, which are often used for stencil wiping, and flat wipes for incidental cleaning in the production areas.

The understencil wiping roll, installed on an MPM UP2000 printer

Question 8

Which Is the Best SMT Stencil Cleaner?

Accepted Answer

When it comes to SMT stencil cleaning, the best results come from nonflammable, slower-drying fluids working with lint-free fabric wipes (no paper with cellulose and glues) to get perfect results. Detailed results depend on the solder paste being used, the age of that paste, the design of the stencil and how it was made, whether you are applying it manually or in an automated system, how often you need to clean and the way you want to clean. It also depends on if you additionally want clean misprinted boards, or the epoxy dispensing systems, or the machinery itself.

Here are a few recommendations —

For simple, manual stencil cleaning our recommendation would be to use the Aqueous Stencil Cleaner (#MCC-BGA). Nonflammable, nontoxic and highly affordable, this cleaner vastly out-performs alcohol. One of our most reliable products, this Stencil Cleaner will never let you down. It removes even dried, hardened paste from the tiniest of apertures. It’s a great stencil cleaning choice and money-saving refills are available.

If your preference is for presaturated wipes, use the MultiTask™ Economy Surface and Stencil Wipes (#MCC-MLCW). Our unique “slam shut” lid makes one-handed cleaning easy, and ensures the tubs won’t dry out while waiting for the next cleaning event. These are the ONLY wipes in the industry without a shelf life and the ONLY wipes in the industry that use money-saving, planet-saving refills.

For stronger cleaning in a presaturated wipe, jump to the Uncured Epoxy Remover (#MCC-EPX) or the Stencil, Squeegee and Misprint Cleaner (#MCC-CDIW). As the names suggest, these are more powerful solvents to help remove more difficult contamination, like uncured chip bonders.

In any case, check out MicroCare’s broad selection of understencil wiping rolls and our huge array of lint-free wipes to use on the stencils you’re cleaning.

Question 9

What's the Technology Behind the SMT Printing Quality Improvements from FP Stencil Rolls?

Accepted Answer

For nearly a decade, stencil rolls from MicroCare have been the industry's leading stencil cleaning roll. Now, the best has gotten better with Micro•Wipe™ FP stencil cleaning fabric.

An SMT stencil looks like thousands of tiny razor blades, when examined under a microscope. Those sharp edges shred old-style stencil wipes, causing defects and rework. Tough, durable MicroWipe FP paper minimizes this problem.

MicroWipe™ FP fabric (not paper) has been rengineered and optimized for fine-pitch stencils. This technology increases through-put while reducing defect rates. The single most important difference is that this new paper is so strong and cleans so well the stencil can be wiped dry, without using solvents. This saves money, improves yield, and extends roll life. This is a unique benefit available only from MicroCare.

Stencil apertures filled with solder paste need stronger fibers for better cleaning

Not All Papers Are Created Equal

The 'FP' fabric itself is different from traditional stencil roll paper. Let's take a look at the differences:

Obj- Paper.Binders.Endview.300x.350x290.RGB.96dpi

Photo, right: Inexpensive stencil rolls normally are made of polyester fibers bonded together with glues. But these glues fill the empty space in the paper between the fibers, limiting the amount of solder paste the wipes can scoop up. In addition, the fibers themselves are feeble and prone to shredding. This microphotograph through a hydroentangled paper shows the open spaces created when glue is not used to hold the paper together. Unfortunately, the cellulose fibers (the flat fibers) on the top of the wipe also shred and become mixed with the solder paste, causing quality problems.

Cross section of fibers in paper used for stencil cleaning.

Photo, right: More expensive rolls, such as the classic Sontara® material, are a 'sandwich' paper made of a hydroentagled fibers of cellulose and polyester. The cellulose absorbs liquids while the polyester provides strength, and the two fabrics are bonded together without residue leaving glues or binders. This is not a bad paper. But the cellulose tends to shred, which decreases throughput and quality. MicroWipe™ FP paper uses only a pure, synthetic form of cellulose. Each fiber is exactly the same as every other, and no glues are used in the paper. These strong fibers pick up solder paste better than any other fiber tested.

Cross section of fibers in paper used for stencil cleaning

Photo, right: In contrast, Micro•Wipe™ FP paper is a hydroentagled mesh of durable, absorbent synthetic rayon. The individual fibers are extremely long, hard (uncrushable), clean and lint-free. This means the rolls can wipe stencils without wetting the paper with alcohol. All of this reduces linting, improves paste pick-up, and enhances absorbency. This improves the results from each cleaning cycle. In effect, each fiber becomes a tiny squeegee, scaping the solder paste off the stencil. Detailed field trials have proven that Micro•Wipes made with Micro•Wipe™ FP will reduce defect rates and cut production costs while boosting quality. It accomplishes this in three ways:

Fewer Cleaning Cycles
Micro•Wipe™ FP rolls reduce the number of time-consuming cleaning cycles, by improving the cleaning during each cycle so you clean less often. Each cleaning cycle eliminated creates time for approximately five printing cycles (~30 secs. vs. ~150 secs.). If the stencil printer is the bottleneck in your facility, this can produce stunning improvements in throughput. At a major PCB subcontractor using DEK stencil printers, Micro•Wipe™ FP rolls pushed production from 36 to 55 boards per hour – a 60% increase in productivity.
Cleaner Apertures
Another improvement results from cleaner apertures. A cleaner aperture allows more paste to flow onto the board, resulting in taller solder pads and improved solder joints. In one prolonged test, Micro•Wipe™ FP rolls increased maximum pad height an average of 11%. Misprints and yield improvements are another area in which Micro•Wipe™ FP technology pays off. One large-scale trial used five SMT lines with DEK printers and Indium 92J solder paste. With Micro•Wipe™ FP rolls, the defect-free through-put jumped to 99.55% from an average of 97.25% — an 83% reduction in defects. All of these improvements makes Micro•Wipe™ FP rolls very cost- effective.
Wiping Dry
This is an unexpected but critical feature for quality stencil printing. Wiping dry means there is no alcohol or solvent to contaminate the solder paste in the apertures. This eliminates slumping and bridges and boosts yield to a surprising degree. MicroWipe™ products are available in every popular configuration, with all the different widths, lengths, diameters, cores, and extensions users require. For details on the FP rolls or custom roll options, call or email Micro Care tech support. We'll get you a stencil roll that meets your needs and your budget.

Part Number	MCC-105DA
Package	Case of 10 Rolls
Weight	8.16 kg 18 lbs.
Size	520 mm x 9.1 m 20.89 in x 30 ft
Technical Data Sheet	TDS

Safety Rating	NA
Absorbancy	445 mL/m2
Color	White
Material	MicroCare FP Fine Pitch Premium hydroentangled
Packaging Note	10 rolls per case
Particulate	3.8
Core Details	20.37' / 530 mm long, plastic, notched
Paper Details	MicroWipe FP Paper
Printer	DEK
Roll Details	Approx. 30' / 9.1 m long x 20.37' / 520 mm wide

DEK Stencil Wiping Roll

Product Information

Applications:

Features:

Product Details

Technical Data Sheet

Electronics