Laser Measuring Tools
Below is a free sample of the depth finder part of the laser measuring system I have developed.
The main reason to use a depth finder is you no longer need to stop the wheel to check bottom thickness with a pin tool. Naturally, some people will not need to check bottom thickness due to long experience and high level of skill, but I am not there yet so I always check, every time and it takes virtually no time now since it happens on the fly real time.
Also, by using the beam spreader, the potter can check the entire surface thickness of a plate simply by looking at the convergence of the two laser beams.
Here you see several types of lasers I have tried. The top laser with constructed frame is a standard laser pointer. Below that is a Harbor Freight laser level still sold for about $30 ( item # 90980). The next laser is the Torpedo Boy by Opcom which also cost about $30. The small laser at the bottom is from Harbor Freight ( item #93242) and cost $3.95 with a magnetic mount, but it appears to be discontinued. I have since found a source , A J Wholesale Distributing which distributes the Pit Bull brand. Their laser level costs about $12.00 (item # CHIL 999)
Depth finders are one tool everyone can use regardless of skill or volume of production
This is the simplest way to mount a pair of lasers for depth finding. I used the nearby cart as aplace to attach a 1.5 " x 1.5" square tube made of steel so that the magnets would hold the lasers.
Here is the depth finder I set up for my wife Barb's wheel. I cut down two of the large laser levels from Harbor Freight and drilled two half inch holes in the tube I attached to the wall with an extension arm ( the laser levels have a hole in them already).
Here is how you set up the initial depth setting. Select boards that total the desired foot thickness (here 3/8") and align the two laser beams so that they meet exactly on the top of the stack. Then, as you open, the beams will gradually converge as you drive your fingers into the bottom of the pot. Blocking the left hand beam before you reach final depth will result in the left hand line disappearing. If you accidentally go too far, blocking the left beam will result in the right hand line disappearing, signaling you the bottom is too thin. The beam spreader also makes it easy to get nice flat inside bottoms on pots and plates.
Be sure to keep water out of the bottom of the pots as this not only interferes with measurement but can also reflect the laser beam into your eyes.