Of Interest







Thermoform Tooling

Since 1990, L. L. Brown, Inc. has specialized in the production of tooling for the plastic thermoforming and vacuum forming industries. During this time, we have developed cutting-edge technology, and state-of-the-art production techniques, allowing us to produce products at a reasonable cost in a short amount of time.

  • The ability to produce the most intricate mold with incredible turnaround is our hallmark. If you would like to learn about how we produce thermoform tooling click here.
  • Our master tooling allows faster mold setups, which maximizes machine run time and decreases project tooling costs. To learn about master tooling click here.
  • Continuous shape thermoforming presents many challenges. To learn more about our patented process for sealing during forming click here
Thermoform Mold Production

The process of mold production begins with a design. This can either be done completely by L. L. Brown, Inc. or imported from customer files into our CAD system using a variety of different formats, including DXF, DWG, PRT, CADL, and IGES. From there, the geometry is manipulated and exported to our Computer-Aided Manufacturing software, where the mold program is written. This CAM system provides the ability to cut virtually any shape imaginable with both two and three dimensional surfaces, such as blended, 3-D swept, and NURBS.  All tools are manufactured to your mounting requirements (i.e. cooling, air, mounting holes). 

L. L. Brown, Inc. utilizes cutting-edge software which can build a "solid" model that is able to be measured, rotated, and sectioned on-screen. This allows us to test the mold program at each stage of development before any material is cut. Not only does this allow us to construct a "virtual" mold which can be compared to the original idea, but it also is very helpful in the detection of "wild moves" which can occur with even the best programmer. This is one of the many tools we use to implement the highest level of quality control.  The final mold product can be inspected using our Coordinate Measurement Machine (CMM).

While manufacturing is the most important step in the mold production process, it is also the least time consuming due to our comprehensive preliminary work. Because L. L. Brown, Inc. is a full service manufacturing organization, we can draw from a variety of different machining capabilities including CNC milling (60" x 30"), CNC turning (10" dia.), and manual machining such as milling, turning, grinding, and plate sawing. This gives us the opportunity to be more versatile not only in the styles of molds we produce, but also in the ways in which we produce them. In addition, we retain an extensive inventory of aluminum plate, ranging in thickness from 1/4" to 2". If material outside this range is required, it can be custom ordered with a minimum lead time.

Special Requirements
Frequently, the mold is only part of the completed product. L. L. Brown, Inc. has extensive experience in the production of special tooling, including plug assists, water plates, and master tooling. To provide total service, we also maintain working relationships with third party vendors in areas such as powder coating and gun drilling.

Some Additional Points
L. L. Brown, Inc. acknowledges the two-tiered nature of our business. In other words, if you don't get the job, we don't get the job. We also understand that there are three selling points for you as a vendor.

  • The time to delivery
  • The quality of the part
  • The price

Keeping these points in mind, we have found that two things make us stand out from the crowd in our field.  We are accustomed to quick turnarounds. It is not unusual for us to be able to deliver a tool within two weeks of receiving a part design, leaving the customer with more time to perfect their design as well as their forming process.

We are accustomed to working with customers' CAD geometry. The benefits of cutting to "your geometry" are two-fold:

  • It eliminates added possibility for error.
  • It allows us to offer additional savings on the final price of the tool.

 Master Tooling

The concept and goal behind “Master Tooling” is to allow the customer to have greater flexibility with their mold base. This means that you are able to use the same tooling build-ups for many different projects. This “master tooling” can be built with many features in mind to allow faster mold setups, maximize machine run time, and to decrease project tooling costs, all of this with the emphasis on increased productivity and profitability.

Master Mold Bases
This portion of the tooling includes a cooling plate along with a series of parallels (or standoffs) that can be constructed to a given height. This entire package is then able to mount into your machine and your project tooling to it. Various height parallels can be made to give you increased flexibility in the thickness of your project tooling. Quick change cylinders are able to be incorporated into this build-up to allow for rapid changeovers and ease of installation.

Front and Rear Clamp Assemblies can be easily added to this build-up in order to pinch off and isolate the plastic sheet during forming. These sheet clamps prevent distortion by holding the sheet flat prior to engagement of the mold or plug assist.

Adjustable Pressure Boxes
On the opposite side of the forming tooling package, is the pressure box assembly. These boxes can be made of many different overall heights so that many project tools can use the same pressure box. With regard to master tooling pressure boxes, the box is constructed of a certain mold width with 3 stationary walls. The forth (front) wall can be positioned at various increments along the pressure box base. This front wall is normally adjustable in 1” increments over your desired range of mold lengths or indexes. The front and rear walls have sheet clamp grooves to work with the front and rear clamp assemblies to grip the sheet. All 4 walls include a gasket track for the specified “O” or “H” style silicone cord.

Upper and Lower Trim Build-ups
Part die cutting can at times be the most difficult part of a production run. It is necessary to keep these build-ups simple in order to “shim” and “tweak” the right areas in order to get the best die cut possible. This tooling also needs to be made solid and true.

For the upper trim assembly, we use a simple plate system to easily adjust to different height parts. Simply add or subtract plates to the build-up to match-up with your cutting die to get your desired height. Assembly brackets are mounted to the top plate in this assembly, therefore, allowing all other plates to be slide into place and mounted quickly in order to get your correct build-up. Each plate has a standard mounting pattern which allows you to standardize the mounting pattern on the cutting dies.

The lower trim assembly consists of a master plate that will mount to the machine platen with a series of parallels (standoffs) which can be added or removed to achieve your desired mold width. Mounted to the top of these parallels are standard cutting anvils for your various mold widths. Of course the top plate of the cutting anvil will be your cutting surface, usually stainless steel plate. This design allows you to “swap” out cutting anvils (various widths) in order to adjust the cutting surface – the rest of the build-up will always remain in the machine as your “master”.
 Continuous Shape Thermoforming
One of the more common types of thermoforming is what is often referred to as continuous shape thermoforming. This process is used to produce a part of unlimited length on a thermoforming machine using an index of only two or three feet. It is of particular use to manufacturers making media for the cooling tower or waste water treatment industries.

L.L. Brown, Inc. has developed and patented a revolutionary gasket sealing tooling technology for the continuous shape thermoforming industry. This tooling technique was developed due to the difficulty in sealing the mold during the continuous shape thermoforming process. This sealing technique incorporates a custom made and replaceable gasket which allows the tooling set to seal along a very complex surface. This advancement allows the industry to maximize the mold size that can be run and produce a more economical and efficient sheet with every machine cycle.

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