Is it a service, a process, or a product?  The Made In USA claim applies to concrete products.  A pure service would not qualify.  A Service tab on Midwest Prefinishing’s (MP) website replaces the more typical Products tab found on other sites.  So, at first glance, MP contributes nothing to its customers’ Made In USA claim.

Afterall, homeowners don’t buy a sheet of rolled-up finishing, put it in their shopping cart, go home, and then glue it to their door’s surface.  It’s not a stand-alone,  finished (no pun intended) product.

Three ways of measuring prefinishing’s contribution.  On the other hand, prefinishing is not exclusively a service either.  First, it embodies physical properties.  True, it takes a backseat to the product itself, existing only as its component or attribute.  But it’s a kind of sub-product.

Second, it’s a process, an element of the Made In USA unqualified claim included in the Federal Trade Commission’s (FTC) standard:

“…all significant parts and processing that go into the product must be of U.S. origin.  That is, the product should contain no-or negligible-foreign content. … The product’s final assembly or processing must take place in the U.S.” (Complying with the Made In USA Standard.)

Third, it adds value to a product.  In an article in the DWM Magazine (First-Place Finishes), Chuck Mierau of Badger Corrugating “estimates the value-added benefit of prefinishing at 35% of a typical pre-hung door order.”  That’s significant.  And, the FTC evaluates “how much of the product’s total manufacturing costs can be assigned to U.S. parts and processing…”

Proud to play a part.  All told, prefinishing justifies its contribution to the Made In USA claim in three ways:  it’s a sub-product, it’s a process, and it adds significant value.  Prefinishers can’t make the Made In USA claim for themselves.  But when MP prefinishes a product Made In USA, it’s proud to be a part of it.

Bob Flexner, writing for Woodshop News, piqued our interest in HVLP spraying by tying its history to the Kirby vacuum cleaner.  In the 1930s, Kirby vacuums included a spray gun attachment to clean carpets and fabrics.  This gun combined the vacuum’s “high volume of air with very little air pressure”… “to atomize liquids.” 

This process grew into the spray process we know today, as HVLP.  According to Flexner, a California government agency coined “the name, ‘high-volume, low-pressure’.”

Inventions create unintended benefits
Jim Kirby, founder of Kirby Co., patented over 200 ideas and inventions.  His place in the vacuum world is secure.  But thanks to Flexner, he is also remembered in the unlikely world of wood finishing (prefinishing, is in a factory setting).

Midwest Prefinishing robotic HVLP sprayer

TE, HVLP, MnTAP: Acronym Overkill
Kirby’s impact is far-reaching.  It affects the environment and material costs.  And, it’s related to another acronym, TE (transfer efficiency).  TE is a ratio measuring how much finish makes it from the can to the surface.  For example, if one gallon of coating is used to finish an object but only half of the material sprayed actually lands on it, then the TE is 50%.  In the hands of a skilled and trained operator, an HVLP gun can achieve a TE of 70%; in the hands of a novice, 60%.

A lower TE increases waste and environmental problems.  But the most important effect is in the finish itself: it failed to build the specified thickness.  In a 2003 report on Spray Painting and Coating Waste Reduction Alternatives, MnTap (Minnesota Technical Assistance Program) wrote, “More importantly, the overall transfer efficiency of a specific coating refers to the amount of coating needed to get the proper dry film thickness.”

Automated HVLP at Midwest Prefinishing
Midwest Prefinishing operates an automated HVLP spray gun to reduce the overspray cloud and to apply more material to the object.  Its automation removes the element of operator skill, improving the TE ratio even more.  Midwest also recycles 100% of the waste.  Taken together, prefinishing is superior to jobsite finishing in most applications.

Less Paint or Stain, More Savings
The higher the TE, the less paint or stain is required to finish a door.  Plus, it reduces waste and air emissions.  Thanks to some unintended help from Jim Kirby, prefinishing grew, making prefinished doors, mouldings, and millwork more affordable and clean.

Does anyone remember the cleaning attachment on an early Kirby vacuum?  Did it work well?

Glue bleed-through on veneered doors frustrates virtually all finishers and prefinishers.  They apply several remedies, some before staining, some after:  sanding, blacklight inspection, seal coats, and touchup.  But these remedies often fail to catch all of the spots. And the cost of prepping these raw doors at the prefinishing stage adds too much to the cost of an economy, production door.  Another problem is origin.  Most stile and rail doors sold in the U.S. originate in China, making quality standards and communication more difficult to maintain.

Glue bleed-through on a stile & rail door

What is glue bleed-through?
Glue seeps through the pores of the veneer, then dries at the veneer’s surface.  Almost invisible on a raw door, it shows up as lighter spots after staining.  Then, it’s often too late to remedy.

How can we prevent it?
Let’s speculate on potential remedies at the manufacturing level.  First, bleed-through occurs more often in open grain species, such as oak, requiring special consideration.  Second, it’s affected by the quantity and application of the glue.  CP Adhesives wrote, “The major cause [for bleed-through] is a heavy glue spread.  By minimizing the spread, you can lessen the bleed through.”  Veneer Systems advises matching the spread to the specie.

“Be aware of the thickness of your veneer and relative porosity of the species you’re working with, and adjust the spread accordingly.  In many instances, a thin spread coupled with mandatory open assembly time (perhaps up to 10 minutes) will be necessary to prevent excessive bleed-through. … Remember, it’s not only the amount of glue, but also how consistently it was applied…”

CP also suggested a filled adhesive for clogging the pores of the wood.  Good remedies from experienced vendors.

Are these remedies practical for the manufacturer?
We assume that production door manufacturers know these remedies.  It’s in their best interests to ship doors without glue bleed-through.  And, to be fair, production manufacturing requires different techniques than the project work related to these glue vendors.  But CP Adhesives and Veneer Systems offer sound advice if manufacturers can apply them to their production lines.  A bit more time, money, and inspection during manufacturing produces more sales and profit later.

Have you tried to remove a glue bleed-through spot?  Were you successful?  If you are in the millwork industry, how often do you see this problem?

Most finishers perform color-matches. But they all qualify the results. And, they’re right; the finish varies due to wood’s inherent characteristics:

• Sapwood vs. heartwood: Sapwood (the outer layer of the tree) is lighter than the heartwood (the inner layer filled with natural, darkening deposits).
• Environment: Grain is tighter on trees growing on a northeast slope as opposed to those growing on a southern slope.
• Absorption rate: Species absorb stain differently due to their unique cell structures. A specie even absorbs it differently within the same wood (e.g., maple).
• Specie variations and mineral: A specie might be white, red, or it might pick up visible mineral content (e.,g., oak)

The devil is in the details… and the panel.
Sometimes, a combination of veneer flitches produces distinct light and dark patterns. They might even create an image. Years ago, a Midwest distributor responded to a complaint and found a door panel clearly resembling the image of the devil. That’s difficult to ignore. The distributor happily replaced the door. But devil images aside, wood lovers expect and enjoy wood’s natural variations.

Gene Wengert, columnist for CabinetMaker FDM, added another variable to the color- matching confusion: viewing angle. He said, “The angle that you view maple from, especially soft maple, will result in [a] different color. That is, if you rotate a piece 180º end-for-end (or even 90º) and view from the ‘other side,’ it will appear different. This is a characteristic of maple.”

What does stain color-matching accomplish?
First, it enhances what mother nature produced: a beautiful, natural, and varied wood surface. It gives it hue and color; it magnifies the grain’s clarity. Second, it closely matches the existing material in order to repair, remodel, or reproduce. It does not control the four qualifications. You want absolute control? Paint it.

Midwest Prefinishing’s automated production process assures an even application of the custom color on doors and mouldings. Its ProFinish process applies a wiped solvent stain, a sealer, and a catalyzed lacquer topcoat. Cut corners with tinted topcoats or by reducing steps, and your color match will suffer. Color-matching can be successful and beautiful when applied correctly and with an appreciation for the uniqueness of wood.

Tell your story. Any unusual images or problems with color- matching? Do you see wood’s variety as a problem or an attribute?