8- Why zinc bar tops can’t be welded or soldered on site.

A challenge facing the zinc bar top industry is how to address seams or joints in the field.  Why can’t the tops be welded into one piece just like the tops from France? There is some very important information that follows, so please listen closely.

This discussion of seams has always puzzled me, as the world goes together with seams.  I have inspected lots of projects in lots of cities, and suffice it to say that seams are an issue for all surfaces across the board. But seams allow movement, which save and stabilize our building projects from the smallest details to the largest structural components: Expansion and contraction.

As a simple answer, tops can’t be welded together because the cores are not metal.  Welding involves melting the base or parent metal together with a filler rod, usually of the same alloy. Attempts have been made at soldering or brazing tops together with a lower-melt filler rod, but these patina poorly and are extremely low strength.

I think what most customers are looking for is a seam that looks and performs better than most of what is offered in the industry today, and this is a fair point. Manufacturers should be looking for ways to improve.

To understand why seams typically can’t be welded or soldered on site, let’s look at the construction of the heritage products coming out of France.

The first point- When true pewter sheet is used for their product, these sheets can be joined over the solid substrate below by placing the lap joint solidly atop the middle of the core- just like alternating Legos for strength.  This gives the top the greatest chance for survival. Imagine trying to join two separate, cantilevered surfaces with the thinnest of wrappers on site.  With unstable cores, it won’t hold up over time when both the core and the metal seams are aligned.  If any dissimilar movement happens, a repair is needed, and elbows on the patron edge of the counter provide the perfect impetus to promote this movement.

The Second point- They can perfectly fill, fair, sand, and polish the sheets because their filler rod IS pewter, the same as the parent material, and it melts at a very low temperature- around 450 F, which makes it easy to work with a torch on site.

What I’m about to reveal is a huge issue, so please listen carefully, because it could save you thousands of dollars on your project or as much as 25% of the total cost.

Most domestic manufacturers of cast/deposition bar tops do not use pewter, and they are misleading their clients about the content of their materials while charging more for “pewter” products. They are, in fact, zinc.

You can take several approaches to discern if real pewter is being used for your project.

The easiest method is to reach out to me by going to our website and sending a message.  After years of experience navigating these waters, I can help you gather the proper information and make an informed decision.

You can also order two identical samples from the same manufacturer in zinc and pewter and see if you can tell the difference.  Do they show different finishes for zinc and pewter in their catalog or on their website side by side? More than likely they will try to convince you that you should select a variety of finishes in different metals or some other sales tactic.  This should clue you in that something isn’t right.

You can also send a sample into a lab for testing.  If you go to rotometals.com and search for “Metals Analysis Test” you can submit a sample for examination.  True Pewter is mostly Tin, so if the sample contains 99% zinc, you have been misled.

While not all makers do, those manufacturers who engage in these bait and switch practices do not deserve your hard earned money, your trust, or association with your brand, and they certainly don’t deserve a 25% markup for a deception they are perpetrating at your expense.  If they’re misleading you about the content of their metal, which is the basis of their business, what else might they be lying about?

The primary metal being used domestically is zinc.  It holds up much better than pewter in terms of everyday wear, and it has the same great patina characteristics. It is the workhorse for the demands expected of large, commercial projects.  Zinc has incredible potential moving forward in the industry.

Zinc has a higher melting point than pewter, and it is very hard to weld, especially on site in such a thin format.  Apart from the fire dangers that exist from ignition of the substrate below, zinc filler rods melt at a higher window than most standard soldering tools allow, and so when other tin based filler alloys are used, they end up taking patina differently, which actually highlights the seam more than it makes it disappear. 

If damage should happen to your tops on site, you can service the piece without costly work to undo the affected piece and free it from the installation if the piece is not held in place with solder.

A major challenge facing manufacturers is how to lessen the appearance of seams on site, and talking honestly about the metals used to create their products.