New Product Development

What drives new product development for a relatively small manufacturing business? In our experience, the bulk of new product development flows from existing customers’ needs.  In the case of W.F. Lake Corp., our ability to bring our many and diverse capabilities to bear are what lead to our successes with new product development (and therefore future growth). Equally important is the ability and desire to get samples into engineer’s hands as quickly and cost effectively as possible. In some cases, these new products are developed for a single application and remain in limited use.  In other cases, those unique properties required for a specific application are useful in a wide variety of other areas and, voila! We have a new product in our standard offering.  Many of our PTFE coated fiberglass sewing threads and PTFE coated Kevlar sewing threads came about in this fashion.

But how did we come to have these capabilities in house?  For W.F. Lake Corp., it started early on with the philosophy that sensible vertical integration not only cuts down on supply chain issues, but also leads to synergies across many disciplines.  It gives us the unique ability to control scheduling of trials, use the varied raw material in our inventory and adjust processing parameters quickly. 

Of course, keeping the lines of communication open with customers and letting them know of your capabilities and willingness to work on development ideas is of utmost importance.  Customers must also feel that finding a solution to their needs is as important to us as it is to them!

A few years ago, we were asked to come up with a high temperature thread with a “fail-safe” built in for possible temperature excursions.  We came up with the idea of combining S-2 fiberglass with 3 ends of Inconel wire that would then be PTFE coated. We were already producing sewing thread with E-glass and stainless steel wire, so this wasn’t much of a reach for us.  Our ability to twist fiberglass threads in-house, and also PTFE coat them in-house, resulted in SGT-243IL being developed within a few weeks. Final approval came quickly and now this thread has become a standard item being regularly produced. 

Another example is as simple as offering a pigmented PTFE coated fiberglass sewing thread to enhance the visual appeal of a finished insulation jacket.  It happens that we run various pigments in other areas of our operation (PTFE coated fiberglass yarn and PTFE coated fiberglass fabric) and were able to choose the right pigment from our stock, enabling samples to be delivered within days. The resulting Black PTFE coated fiberglass sewing thread is also now a standard product.

We apply these same principles across all product disciplines, including  PTFE coated fiberglass fabrics and PTFE coated fiberglass belts, where we coat, slit, sew, heat seal, sheet, and fabricate a variety of products.  Combining those capabilities has resulted in some unique products that solve interesting processing requirements resulting in Custom Materials.

If you have an opportunity that requires a unique high temperature PTFE coated sewing thread, draw cord, fabric or belt or any combination thereof, zing us a note or call.  We stand ready to put our capabilities to work quickly and cost effectively for your needs.

“Green” By Design

Do you ever wonder if what you produce makes a difference in peoples’ lives or has a positive impact on the environment? Our products and your products are “green” by design. Working together with our valued customers, our products can and do have a positive impact on the environment and on the lives of others.

Here at W.F. Lake Corp. we produce a number of products that contribute to a better environmental outcome. A couple of the many examples follow:

Our PTFE coated fiberglass sewing thread used to sew filter bags used in flu gas filtration media. This is a difficult operating environment that few products are capable of handling, but our thread can take the punishment. The filter bag itself cleans particulate from the air stream before it can be released into the environment.  The PTFE coating allows for easy cleaning of the bag while enhancing chemical resistance and sewability.

Another example is in reduced energy consumption through insulation: Any time you can reduce energy consumption, the environment wins!  Our PTFE coated fiberglass sewing thread is used to sew high temperature insulation jackets for things like gas turbines, pipelines, rotary kilns, etc…. Wherever you live, you know that simple, effective insulation can dramatically reduce your energy consumption.  Imagine how much energy can be saved when properly insulating very high temperature industrial operations!  The threads we manufacture are capable of operating against the hot side facing of these items where other threads would immediately fail.  Our PTFE coated S-2 fiberglass sewing thread, for example, operates to 1400 deg. F, while our PTFE coated Quartz sewing thread withstands 2000 deg. F!  Not only can they operate at these extremes, they facilitate the reuse and repair of these same insulation jackets.  We all know that “reuse” and “repair” are far better action words than “replace” when it comes to the environment!  And by limiting heat loss, our thread contributes to longer operational life of sensors, thermocouples, instrumentation, electric motors, etc…

We are also proud to say that we manufacture products that help make life safer for others as well.  When it comes to operator safety, our PTFE coated fiberglass sewing thread and PTFE coated fiberglass draw cord is used to help protect operators from extreme temperatures and chemicals.  Insulation jackets sewn with our thread keep heat where it belongs, thus minimizing the chance of an accidental skin burn, while safety spray shields using our thread and draw cord help contain chemicals in the event of a valve or flange leak.  Our PTFE coated fiberglass threads and draw cords won’t burn or support flame, will not rot or support fungus and are virtually unaffected by most chemicals.  When our customers use our products to fabricate these products, they are helping others remain safe every day. 

We at W.F. Lake Corp. thank our customers that use our products to make life a little safer and the environment a little cleaner while providing good, meaningful jobs in their respective communities!

PTFE Coated Fiberglass Sewing Thread…what is it worth to you?

“Wow, that thread is a bargain!”… haven’t heard that in a while, but when it comes to PTFE coated fiberglass sewing threads or draw cords (or any of our other PTFE coated sewing thread products) used to fabricate insulation jackets, safety spray shields, filter bags or other high performance products, our sewing threads are almost always the least expensive component of any finished product and perform perhaps the most critical function by holding it all together.

When manufacturing a safety spray shield or an insulated valve cover, certainly the fabric cover material itself (whether it is PTFE coated fiberglass or another high-performance material) is by far the most expensive component.  Take a look at the actual weight or length of sewing thread holding all of this together and consider that a typical yield for R753-18 is in the range of 2000 yards per pound… how many pounds are in that jacket (certainly less than one).  Then look at your cost of thread used versus cost of fabric used… not even close!  The same goes for the PTFE coated fiberglass draw cord holding the cover closed… not even close!

Certainly the “work-horse” of the high temperature sewing thread market is our PTFE coated sewing thread made with E-glass fiberglass.  This is our R753-series thread.  The cost per pound certainly increases when using S-2 glass threads or Quartz sewing threads, but the performance characteristics also improve dramatically, especially when it comes to maximum operating temperatures.  Then look at our PTFE coated Kevlar* threads where the cost may seem high, especially if we’ve twisted in one or more ends of Inconel wire…but that yield is in the range of 3,000 yards per pound…a pretty good deal we like to think!

From a manufacturing standpoint, it is worth noting that when yields are in the thousands of yards per pound of thread, processing time is also great.  Twisting time, coating time and of course raw material costs add up to what may seem like an expensive thread, but this is not cotton and much is demanded of it in the field.  We perform all twisting and coating functions in-house, which allows us to react quickly to new opportunities, make small runs and control costs as much as possible, but when you consider what this thread does and how relatively little of it is a cost component in the final product, you can’t help but think “Wow, that thread is a bargain!”.

                                                                                                                *Reg. DuPont

Supply Chain Update

First, thank you for your continued support.  As an Essential Business, we have been in continuous operation since this pandemic began, following CDC guidelines with the safety of our employees and their families our #1 priority.  Now, as we continue to navigate through this pandemic response, we all may want to take another look at our operations and see what lessons can be applied to our businesses. 

Lessons have certainly been learned about supply chains at the national level concerning PPE equipment! As a manufacturing operation, consideration should certainly be given to the length of our own supply chains and the number of connecting links that hold it together. 

When it comes to PTFE coated fiberglass sewing threads, yarns, draw cords, and other products, rest assured that you are working with perhaps the shortest “supply chain” in the industry.  Our capabilities are second to none and give us maximum control of quality, lead times and costs. Our capabilities also allow for timely and cost-effective new product development.

Vertical integration has worked wonders for us.  Initially written in 2018, this blog post still applies today.  Vertical integration made sense to us years ago when we started this business (1991) and now seems more important than ever! Please take a moment to read that old post… and rest assured that when you work with W.F. Lake Corp., you are working with a company that removes as many links in the supply chain as we realistically can, with the vast majority of raw materials coming from the USA! 

So, what do you guys make?

In casual conversation it is not unusual to hear the question “So what do you do for a living?”. Whenever that question comes up, I try to gauge the interest in my initial reply before going into too much depth

My immediate response to “so, what do you do for a living?”
is that “our products are on the space station and in your local fast food
restaurant and many places in between”. If their eyes haven’t glazed over,
and if a follow up question is asked, I’ll get into more detail. We are
fortunate to run a business that crosses over many industries with many neat
applications that are interesting to anyone who is involved with manufacturing
in just about any way. The second line in my reply is that you may not have
seen or used our products, but they have played a small part in your life!

PTFE coated fiberglass products find their way into diverse
applications because of their
unique operating properties
. High temperature resistance, electrically insulating,
chemical resistant, non-stick, will not burn or support flame, excellent
tensile strength, FDA approved for direct food contact, etc. 

In industrial applications, Teflon* coated fiberglass
fabrics, tapes, belts, sewing threads, cords and yarns take advantage of one or
more of these properties and can be fabricated or further processed to make
some pretty unique items. The space station items include PTFE coated fiberglass
sewing threads
(space suits, insulation panels), PTFE coated fiberglass
braided tie cords and lacing tapes (wire bundles, draw cords) and even PTFE coated fiberglass
(insulation quilts, covers).  When it comes to your local
fast-food restaurant, our PTFE coated fiberglass fabrics end up as “baskets”
in toaster ovens, liners for clam-shell grills and cookie sheets for baking,
well, cookies
!  Some more unique applications include embroidery
threads for very high temperature exhaust gas shields (won’t fade in the high
heat and won’t burn or support flame and are not attacked by any fuels or
hydraulic fluids), dryer belts
for screen printers
(high temperature, non-stick), smoker
rack liners for smoke-house meats
(FDA approval, high temperature,
non-stick), and PTFE
Coated fiberglass sewing threads
(stitching insulation blankets for gas
turbines, exhaust manifolds, engine compartments).

If you’re still reading, then at some point you developed an
interest in manufacturing at some level. Thanks for hanging around!
Manufacturing appears to be on the rebound and many exciting applications for
PTFE coated fiberglass products are certainly still ahead…we look forward to
working with you on your unique application. Zing us a note for more information!

9 Tips for Extending the Life of Your Dryer Belt!

Screen print dryer belts made from PTFE coated fiberglass mesh operate in extreme temperatures and offer release characteristics that few other materials can match…but they are not inexpensive, and care should be taken to get the maximum life from these belts.

Here are a few tips to help make your belt last a little

  1. Take a moment to be sure when ordering a new belt that you get the dimensions right. These belts are nearly impossible to modify in the field given the extreme heat and pressure required to seal edges and reinforce the “bullnose” for the alligator lacing (or other splice type).  If your mesh dryer belt is too long, it will have to come back to the factory to be shortened… if it’s too short, we will have to make a “dutchman splice” that will lengthen the belt, but you will now have 2 splices in your belt and tracking issues may result.
  2. Take time to install a new PTFE coated fiberglass mesh dryer belt correctly.  Here’s a link on how to do it right. Be sure you get it started right and you will have better shot at a long belt life.
  3. Load the belt carefully. Most screen print dryer ovens do not have automatic tracking systems installed.  They typically run slow and can often run for years with no adjustments if installed properly (#2 above).  In order to give your belt a good chance of tracking properly be sure to load it evenly.  You can load the center of the belt or alternate left and right as the dryer runs.  Avoid heavier products placed only on one side of the belt, as this can pull the belt out of square and distort the weave. 
  4. Avoid crowned pulleys. Crowned pulleys are sometimes used in belting applications, but with a Teflon coated fiberglass mesh belt, anything but the slightest of crown in the pulley can actually split the belt in two.  Remember that these are made with PTFE coated fiberglass yarns and, like anything fiberglass (imagine a fishing rod) if you repeatedly bend it over a sharp radius, you will wear it down, and possibly break it at that point.  A mesh dryer belt is constantly flexing as it travels over pulleys and deflects slightly under the load it is carrying.  If you have your heart set on installing a crowned pulley, check with us first to see how much of a crown you can safely put in place (hint: It isn’t much!).
  5.  Do not over-tension the belt. If slippage occurs, the first thing to do is to clean your drive pulley.  There should be enough friction as delivered by the factory to drive the belt without over-tensioning it. These belts are made with a woven PTFE coated fiberglass yarn and are not intended to be tensioned like a V-belt on your car!  You can easily pull the splice out of the end of the belt, tear the alligator lacing at the corners or distort the belt to the point where it does not track properly (you could also take the dryer out of square, causing tracking issues).  If you need additional friction in order to keep the belt moving, contact us and we’ll let you know what we think is the best way to get it moving. It involves applying a “lagging” tape to the drive roll, but you must do it right!
  6. Support heavy loads with a slider bed underneath the belt.  Of course, if you purchased your dryer with printing glass panels in mind, you no doubt already have a support bed of either flat panel (stainless steel) or rollers to hold all that weight.  If you are retrofitting your dryer, be sure to consult the dryer manufacturer before making significant modifications but do support the load properly one way or another because these belts are not intended to support heavy loads in free-air under tension.
  7. Do not stop your belt under a hot lamp.  If you’re using an infrared curing dryer (electric or gas fired) be sure that the belt does not stop under a lamp that is hot. High temperature heat sources can destroy the PTFE coated fiberglass substrate, effectively “burning a hole” in the belt.  If this does happen, this is one of the few repairs you can make in the field.  Contact us for a repair kit that will include materials needed to make basic repairs.
  8. Take care not to let a cart, box or other item contact your mesh dryer belt while it is running. We’ve seen a number of belts split in two when a cart or a box was allowed to rub against the belt for an extended period of time.  A short tear can sometimes be patched in the field, but long tears often ruin the belt, as there is no good, cost effective way to bond it back together.
  9. Finally, do not cut your belt off the machine in order to measure it. Use our simple guide to measure it properly. This seems obvious, but we’ve seen that happen and it can be wasteful.  In many cases, we’ve made new dryer belts for customers who then send us their old belt that is still in reasonable shape and we’ll give it a “tune-up” that allows it to be used as a spare, backup belt.

We’ve been manufacturing PTFE coated fiberglass fabrics, tapes and belts since 1991 and are ready to help in any way we can.  Just “zing us a note!”

PTFE Coated Fiberglass: Sintered versus Unsintered

The definition of “Sinter” is: “To make a powder coalesce into a solid or porous mass by heating it without liquification”.  We typically think of sintering as it relates to metal (like bronze or brass).

W.F. Lake Corp. manufactures both sintered and unsintered materials.  With sintered PTFE, we essentially have taken a PTFE powder dispersed in water and fused it using heat into a hard, slippery coating that operates at very high temperatures, is chemical resistant and very few things stick to.  These are sintered PTFE coated fiberglass products.  Unsintered products are essentially an impregnated coating of PTFE that is dried in place, but not fully fused. It has a “waxy” feel and is less abrasion resistant.

Why sintered?  Sintered PTFE coated fiberglass fabrics, tapes, belts and sewing threads are the typical form of PTFE coated textiles you see in the marketplace.  They are the work-horse products for food processing (belts and sheets), packaging (L-Sealer bars), molding (composite release sheets), flu-gas filtration (PTFE coated fiberglass sewing threads), high temperature, hot face insulation (S-2 glass, Quartz sewing threads, etc…), and many other applications.  In these cases, PTFE powder suspended in water is fused at high temperatures (sintered) to form a solid PTFE coating.

Why Unsintered?  We are unique in that we also coat many of our fiberglass yarns with unsintered PTFE.  This process requires precise temperature control to essentially “bake” the PTFE particles without fusing them together.  This leaves a waxy type coating that has both penetrated the fiber bundle and leaves a portion of the coating on the surface of the yarn. In most cases, these yarns are braided over wire conductors or made into lacing tapes and tie cords. The advantage an unsintered PTFE coating is that it allows for further processing and bonding of subsequent layers of PTFE; in the form of PTFE films, coated fiberglass fabrics or even additional PTFE dispersions.  When all of these are finally fused, or sintered, our customers form a homogeneous coating that very effectively resists chemicals, operates at high temperatures, will not burn or support flame, will not rot or support fungus and provides excellent electrical insulation.

Most of us use sintered PTFE products virtually every day.  Pots and pans, baking sheets, even breathable, water repellent rain ware (and sometimes vascular grafts!).  Unsintered PTFE products in daily use are less prevalent, but are available as Thread Seal Tape (unsintered PTFE film), packing (valve stems, shaft logs) and gaskets (valve stems), etc…  PTFE is an amazing material.  Give us a call with any questions or application opportunities… we’re here to help!

Our Magic Principle: Vertical Integration!

How is it that W.F. Lake Corp. can turn out so many variations of PTFE Coated fiberglass threads, draw cords and yarns so quickly at competitive prices regardless of quantity?

One magic principle: Vertical Integration!

When W.F. Lake Corp. started some 27 years ago, one goal was to be able to develop specialized products in relatively small runs while supplying the “standards” at competitive prices. We had lots of ideas and realized that you have to get a sample in an engineer’s hands as quickly as possible in order to remain relevant.

Ideas are one thing, bringing them to fruition is another! So we started out focusing on our strength, i.e. PTFE coating of fiberglass materials; the standards: PTFE coated fiberglass fabrics, tapes and belts, sewing threads, yarns and draw cord.

As we continued to grow, it became clear that vertical integration could make us more competitive. We certainly could have kept going without vertically integrating, but opportunities for creative new products kept coming up!

Our first move was to greatly expand our braiding operation. We had improved the basic PTFE coated fiberglass draw cord through our coating expertise, and we were buying lots of braided fiberglass. This allowed us to “become our own best customer” as well as improve innovation. Those first braiders are long gone, as they came to us in pretty rough shape and we worked them pretty hard, but they confirmed that we were going about this in the right way (“walk before you run”). We were now able to make lots of different braids with lots of coating modifications. And since we controlled the braiding itself, new products were in our customer’s hands in days, not weeks or months. Additionally, small volume runs became simple for us…no more minimum order quantities from vendors! Want to try 20 feet? No sweat! How about a braided, PTFE coated Quartz tie cord? Sure.

Next up was the twisting operation. We were chugging along with industry standard products and we had developed a few specialized PTFE Coated Fiberglass Sewing Threads. It was time to look into vertically integrating into the twisting operation. This is a bit more complicated, but we started buying and re-furbishing twister frames. Suddenly, all of those crazy ideas were easy to test out, and customer driven opportunities were addressed quickly and cost effectively. Out came PTFE Coated S-2 fiberglass threads, threads with stainless steel wire, PTFE coated threads with Inconel wire, PTFE coated Kevlar* threads with as many as 10 ends of stainless steel wire, PTFE coated Quartz sewing thread, different colors, etc…How about a PTFE coated Kevlar/Carbon Fiber Composite thread… can do! Some of these are small volume products, but that is fine with us! As a bonus, our twisting operation also feeds the braiders and the yarn coaters!

I could go on and on, (yeah, we know) but I’ll wrap it up! Suffice it to say that we continue to vertically integrate operations when it makes sense. Exploring new ideas is now simply a matter of walking out to Mark in twisters, or Fred in braiders, or Dave in the coating room, or any of a number of other employees and asking them to help out. They have, over the years, developed a keen understanding of what our equipment is capable of and they can usually get us samples very quickly, sometimes in a matter of hours!

Over the years, we have gained a good deal of knowledge about what today’s high performance materials are capable of and what combinations of materials make sense. We’ve gotten pretty good at working with customers to get them what they need in a hurry. Give us a call or zing us an email with your next development opportunity…if we don’t already have a solution, we are willing and able to give it a go and deliver samples in a hurry!


*Kevlar by DuPont

PTFE Coated Fiberglass Lacing Tapes and Tie Cords

W.F. Lake Corp. manufactures a wide range of PTFE coated fiberglass lacing tapes and tie cords that meet a number of military and commercial specifications.  These products are amazing in their long term performance characteristics.  Once installed, they rarely, if ever, need attention…no one wants to open up an airframe for a failed “zip tie”!  Unlike plastic zip ties, our products will not burn or support flame, will not rot or support fungus, are unaffected by virtually any chemicals including aviation fuels, diesel fuel, gasoline, oil, hydraulic fluids, etc.  They are unaffected by UV light and are highly flexible due to the nature of the PTFE coating and braiding process used in their production.

Of course, a “Lacing Tape” is a flat braid, while a “Tie Cord” is a round braid.

W.F. Lake Corp. puts extra effort into our lacing tapes and tie cords by first coating each fiberglass yarn with PTFE prior to the braiding process. This extra step of glass impregnation before braiding acts as protection against fiber-to-fiber abrasion during fatigue.  Also, when high local stresses occur, the PTFE coating allows mechanical transmission of the load within the lacing tape or tie cord to maximize load sharing between the fibers.  Typically, the PTFE coating represents 15% of the overall braided cord.

Some of our PTFE coated fiberglass lacing tapes and tie cords have been tested for outgassing properties by NASA (contact the factory for the location of this information).  Many of our products are also designed to meet military and commercial specifications including:

Military Specifications:


Marshall Space Flight Center


When it comes to high performance braided lacing tapes and tie cords, think of W.F. Lake Corp.!


A lesson in PTFE…what exactly is it?!

What is Teflon*? What is PTFE? W.F. Lake Corp. uses PTFE from a number of sources. Teflon* is PTFE which is polytetrafluorethylene. Is there a difference?  No.  There are different grades, of course, and some different chemistry to a point. Check it out on Wikipedia (I know… I know) but it gives a pretty accurate account of what it is, where it is used and how it was discovered. It goes by many names, but as most of us in the industry realize, the best known brand name of PTFE is Chemours’ Teflon* (Teflon* is a registered trademark of Chemours.  Chemours is the company recently spun off by DuPont).  It is an amazing material and is used in many applications including our high temperature PTFE coated fiberglass products like fabrics, tapes, yarns and sewing threads.  So when someone looks for Teflon Coated Fiberglass Sewing Thread, they will often find PTFE Coated Fiberglass Sewing Thread in the search.  While we do use some Chemours products, we don’t always use Teflon* brand.  We therefore advertise our products as “ PTFE coated fiberglass sewing thread “, or “ PTFE coated fiberglass fabric “ etcetera.

As always, give us a call or zing us a note with any questions.  We manufacture a wide range of PTFE coated fiberglass yarns, threads, fabrics, tapes and belts. We may not be the largest processor of PTFE coated fiberglass products in the world, but we may have the most diverse offering.  We’re proud of our ability to apply this amazing fluoropolymer to such a wide variety of materials, providing solutions for your most demanding applications.

*Teflon is a registered trademark of Chemours