Copyright 2019
Tidewater Woodworking GuildSite by President:Jim Francis Vice President: Scott Fell Treasurer:Greg Guertin

TWWWG Heading imageman glitter
July 2019
July marks the beginning of the "too hot to work" season
Web Links At the Meeting Last Meeting Notes Tip of the Month Editors Notes
Product Reviews

What's In The Newsletter

  • President' Comments
  • So What's In Your Sandpaper?
  • Industry News - SawStop

From the President ...

Welcome to July!  Fairs, rodeos, road trips, family/friends; it's getting hard to find shop time.  At this month's meeting, Jon Fischer will attempt to alleviate the deficiency by providing a program on wine racks.  In addition, we'll have a happy hour (6:00 PM to 7:00 PM) of barbecue and water melon (bring your own drink).  Also, bring your show/tell items, and shop treasures for our monthly raffle.

Looking for some woodworking inspiration outside furniture?  Check out these sites:

See you at our meeting on the 22nd!

Jim Francis

So What's In Your Sandpaper?

I subscribe to all of the woodworking magazines and I keep saying to myself “if they have another tip on how to store your sandpaper, cut your sand paper, how to organize your sandpaper, etc. that I will quit reading their magazine forever (same goes for the sawhorse)”!  To me sandpaper is one of the lowliest items in the shop and it goes hand in hand with sanding my project.  Necessary but boring. I can tell good sandpaper from cheap sandpaper but why?

There was an interesting article in the Wood Magazine this year by Jim Heavey on sandpaper and if you are interested in reading in detail take a look at the March 2019 edition.

Jim breaks down sandpaper knowledge into five items:

●  Size of the abrasive

●  How densely the abrasive is packed

●  The type of abrasive

●  The backing of the material

●  Whether the sandpaper has stearate or not


Size of the abrasive –

Most of us in the US know grit by just a single number (the CAMI system).  Coarse grits are usually 40 to 80 grit, medium grits run from 100 to 150 grit and the fine grits range from 180 to 320 grit.  Europe uses a system called FEPA.  You will usually see their grits listed as say P220 for 220 grit sand paper.

How densely the abrasive is packed –

You will see sandpaper labeled as open coat or closed coat.  Open coat paper has less dense coverage (about 30%) of grit to keep the sawdust from clogging the paper.  Closed coat paper has almost 100 % grit coverage and offers quicker sanding on hardwoods.

The type of abrasive –

Garnet, a natural mineral usually found on inexpensive sandpaper.  It does not last very long.

Silicon Carbide, hard material but brittle and fractures easily exposing new cutting edges as you sand.  A good choice for finish sanding and rubbing out finishes.

Aluminum Oxide, very hard material, works from coarse sanding to fine sanding.  Good for hand sanding and power sanding.  This has become the go to sandpaper for most woodworkers.

Ceramic, better suited for metal working but you may find it mixed with silicone or aluminum oxide particles to create a longer lasting sandpaper.

Backing material –

There are several types of backing material and the US manufacturers use a grading scale from A to D.  A is the lightest weight and D is the heaviest weight.  A, B, & C papers are great for hand sanding while C & D hold up better for the coarser grits.

Stearate or non-stearate –

Stearate or self-lubricating sandpaper adds a dry metallic soap between the grains of the grit.  This keeps the sawdust or swarf from sticking to the paper as you sand.  You will usually find these sandpapers in a well-stocked auto parts store.

Another great article on sandpaper came from the Woodcraft magazine dated February 2008.  Of special interest in the article was on Micro-Mesh sandpaper technology and Mirka’sAbranet sandpaper.  The article goes on to discuss how these unique sanding pads operate.

Another sanding “paper” used in the workshop is the synthetic nonwoven abrasive pad which I call the 3M pad after the inventor.  The problem I have with these pads is trying to remember what color represents what specific grit.  A white pad is extra-fine, approximately equivalent to 600-grit sandpaper; gray compares to 220-grit; maroon, 150-grit; and green, 100-grit. The difference among them relates to the coarseness of grit that's impregnated in the plastic strands, not the thickness of those strands.

Nonwoven abrasive pads offer a couple of advantages over steel wool, especially when you use water-based finish. They don't contain oil, which would adversely affect the bonding of the finish, and they don't leave behind bits of steel that can rust, ruining the appearance of a finish.

 Return to Top


Industry News - SawStop

During the hot summer months and the energy levels low I thought that doing a piece on SawStop would be a quick article since they have not been around for long like all of the previous manufacturers mentioned in this year’s newsletters.  I have found this manufacturer to be of great interest for a 20 year old company!  As an example, who would have expected a high tech tool company in the 21st century to have its humble beginnings in the hayloft of a barn?

SawStop began its beginnings in 1999 by Dr. Steve Gass.  Dr. Gass was a patent attorney and amateur woodworker with a doctorate in Physics.  It only took him two weeks to come up with his blade braking theory and another week to build his first prototype table saw!  As most of you have seen in the SawStop videos with the blade coming to a screeching halt when it hit the hot dog, imagine testing a PROTYPE saw on your own finger with unproven technology.  Dr. Gass conducted his first test with his own finger in 2000!  He applied Novocain to his left ring finger, and after two false starts, he placed his finger into the teeth of a whirring saw blade. The blade stopped as designed, and although it "hurt like the dickens and bled a lot," his finger remained intact.

After showing his prototype saw to the International Woodworking Machinery and Furniture Supply Fair trade show in 2000, Gass attempted to license his innovation to Ryobi, Delta, Black & Decker, Emerson, and Craftsman.  Gass was told that he was unlikely to succeed in convincing major power tool manufacturers to license SawStop technology.  The failure to license the technology to any manufacturer prompted SawStop to become a manufacturing company itself and the company's first saw was produced by a Taiwanese manufacturing plant in November 2004. By 2005, SawStop had grown to "eight people out of a two-story barn Gass built himself.

To most observers including myself that might seem like the rest of the story but it goes on.  In 2008 SawStop provoked opposition from the Power Tool Institute which represents Black & Decker, Hilti, Hitachi Koki, Makita, Metabo, Bosch, Techtronic Industries (owner of Ryobi), and Walter Meier Holdings (WMH Tool Group, owner of JET and Powermatic. In April 2008, they told Congress that SawStop's braking system is:

●  Dangerous because it requires the user to come in contact with the blade before activating;

●  Unproven, particularly in terms of durability;

●  Prone to false trips caused by commonly available wet and green wood;

●  Potentially vulnerable to latent damage that cannot be inspected and may cause a hazard;

●  Costly to the user because once activated, saw blade and cartridge must be replaced; and

●  Significantly more expensive, costing at least 25 percent more than a standard saw and ranging upwards depending on saw type


What was PTI’s objection to the braking system? “it would destroy the market for the cheapest, most popular saws, adding $100 or more to the price of consumer models that typically sell for less than $200."  Instead the members developed "new plastic guards to shield table saw users from the dangers of a spinning blade" and began selling models with that feature in 2007.  In May 2011, PTI says "its member companies had received no reports of injuries on the 750,000 table saws with the new guard design."  Money talks!


The Power Tool Institute is also concerned that SawStop patented technology might force other manufacturers to pay unreasonable royalties to SawStop. The Institute also suggests that SawStop users have become less careful, because they have a "sense of security" in the ability of SawStop to protect them, a behavior called risk compensation.

Now that you think the Power Tool Institute is just a bunch of money hungry bullies, take a look at how others view Dr. Steve Gass.  Dr. Gass has been lobbying government officials to force manufacturers into licensing his agreements!  He wants them to pay him royalties for his technology.

In 2015 competition to the SawStop began.  Robert Bosch began manufacturing a competing product called the Bosch REAXX Jobsite Table Saw, which also has finger-saving ability, but using a different technology. The Bosch saw retracts the blade below the table, but unlike SawStop, it does not stop or damage the blade.  Herein begins the litigation process between SawStop and Robert Bosch

From my investigation it looks like SawStop has about 100 patents on their blade stopping technology.  In 2016, before a patent attorney judge, two of the SawStop patents were determined to be infringed upon by Robert Bosch while two other patents did not infringe upon Bosch’s new design.  Legal proceedings strung out into 2017 to give attorneys time to digest the rulings. 

In August of 2017, the Consumer Product Safety Commission (CPSC) again held hearings on table saw safety. Despite statements made by the saw industry claiming they are making their saws safer, without resorting to a finger detection technology, injuries and amputations continue to rise, and now stand at over 4,000 per year.  Because of intensive lobbying by the saw industry, the House Appropriations Committee attempted to forbid the Consumer Product Safety Commission from passing new rules on saw safety.

As of May 2018 CPSC still has not announced a decision.

Other interesting facts on SawStop.

The SawStop patents begin to expire in August 2021, with filed extensions this could extend until April 2024 for the early patents. Given that there are about 100 patents, patent protection for this product line may continue for some years.

According to SawStop, the system has restrictions and limitations:

●  The braking system must be deactivated when cutting very green or wet timber.

●  Non-conductive blades or blades with non-conductive hubs or teeth cannot be used.

●  The braking system is designed to work with kerfs from 3/32″ to 3/16″; using thinner or      thicker kerfs limits the saw's ability to stop the blade after accidental contact, likely resulting in more serious injury.

●  It is impractical to retrofit into existing table saws.

●  Activating the braking system damages the blade.


In June, 2017, SawStop announced the acquisition of SawStopLLC by TTS Tooltechnic Systemsa third-generation family-owned company based in Wendlingen, Germany. The TTS family of companies includes FestoolTanosCleantec and others, and employs more than 2,500 people around the globe.  With the acquisition by TTS, Dr. Gass stepped down from president of the company to Vice President of Innovation.  In this role he will be focusing his efforts on new products for the company.

Now you know the rest of the story (at least for today!).

  Return to Top

Joomla Templates: by JoomlaShack