BallOfSpray

UPDATE:

In 2008, when I received my first Digital Slot Calipers from David DiPol, I was perplexed and then amazed with this new method of measuring DFT (distance from tail). Since then, I have come to believe that it is the only consistent method for measuring DFT. For this reason I no longer use my much more expensive and name brand Mitutoyo Calipers. For a quick explanation of how DFT measurement is done with the Digital Slot Calipers, go to http://www.slotcaliper.com.

Having solved the DFT consistency problem, David DiPol then set out to solve the final remaining common measurement problem. Skiers who use the jaws measurement method for fin length will often find discrepancies in their measurements when they change calipers. This is because most calipers have an indentation at the base of the jaws. The indentation is inconsistent from caliper to caliper. David solved this by having calipers made without the indentation. For skiers using the jaws method, the new version of the Digital Slot Calipers is clearly superior.
In the above photograph you can see the new version of the Digital Slot Calipers. The blue arrows show where the measuring surface precisely meets with the leading and trailing edges of the fin. For More Information http://www.slotcaliper.com David@slotcaliper.com (504) 915-9292
	Calipers on the top are my Mitutoyo. The blue arrow points to the indentation typical of most calipers not specifically manufactured for waterskiing. The calipers on the bottom is the Digital Slot Calipers, the blue arrow is pointing to a perfectly flush measuring surface.

When I arrived  home today, I found a UPS box at the front door. Inside was a Digital Slot Caliper made by Dave Dipol. My first reaction was “Well, that is not going to work”. Ten seconds later, I realized that the slot caliper is pure genius!

With the Slot Caliper, getting repeatable DFT measurements is almost foolproof. 
To use the Slot Caliper, simply slide the slotted shaft onto the fin. Once the fin is in as far as it can go, slide the lower jaw until it hits the fin. Zero out the caliper and  then move the lower jaw back past the tail of the ski allowing the caliper lie flat on the bottom of the ski. Then slide forward to reveal tail measurement number.

It is a little hard to explain in writting but the first time you use the slot calipers, you will wonder how you measured without them. I hope Dave does not ask for his simple back, they are already in my tool box.

For More Information
http://www.slotcaliper.com
David@slotcaliper.com
(504) 915-9292