Recalibration and Tune-up
The first thing you should do when you get your instrument from me is measure a smooth ceramic tile under wet conditions and record that baseline value on the back of the tile with a felt-tip marker. Before each outing with your instrument you can re-check its calibration to verify that it is still in the ballpark. If it is out, return it for service. There are several things that affect the readings of this fine tribometric instrument: the velocity of impact, the angle of the test foot to the surface, the alignment of the output pointer and testfoot contamination. The velocity of impact is affected by operating pressure and lubrication of the piston seal. The faster the motion, the slipperier the readings you will get on wet surfaces.

If your pressure gauge is out of calibration, you will get biased results. But the commonest error arises from contamination of the friction pad. If you can't restore it to its pristine condition by washing and sanding, return it to me for recalibration.

The $200 Deal
When you return your XL to me for recalibration I also do external calibration, verifying the XL's accuracy on a test tile. This is all included in the calibration/tune-up package offered in my standard deal. From locations within the US, send your XL to me along with a check for $200.00, and I do what it needs to restore it to like-new operating condition. For overnight return shipping, add another $50.00.

From Canada, send a check for $300.00 USD (which covers the extra documentation and shipping red tape). From elsewhere outside the US, send a draft for $600.00 USD. No purchase orders or billing. Send the check with your instrument. If you can't send a check with your instrument, this service is not available to you. It is recommended that your instrument be re-calibrated at least annually. For instruments in heavy use, more frequent service will be required.

What If My Pad Becomes Contaminated? Scrub the pad with a liquid soap solution in warm water and re-sand it to remove the adulterated "skin" on the pad. A good liquid detergent will remove most contaminants. Then re-sand it good with 180 grit paper after it dries. Don't sand it wet.

How About Shipping the XL?
If you save the box your unit was shipped in, you can reuse it to return it for warranty or calibration work. Just pack the meter in the box inside of its softsides carrying case. If you have lost the shipping box, you can use an empty copy paper case. You can cut it down a couple of inches or pack it with a couple of sheets of newspaper. Remove all other books, parts and accessories from the case pockets so as to reduce shipping costs. I don't need your tools or books for the calibration. I have my own. Don't ship it without its cerrying case.

Also label it Fragile. It is not fragile, but you would not believe the severe treatment they can give anything not labeled fragile.

If you are shipping by US Mail, ship to: William English, Inc., P. O. Box 985, Alva, FL 33920
If you are shipping by a UPS or FedEx overnight, ship to: William English, Inc., 20500 North River Road, Alva, FL 33920.
If you use a form a shipment that requires a signature for delivery, your instrument will likely be returned to you because if I'm not here when they come, they won't leave it.

The $200 service deal is for instruments returned within one year of the last service. After that add $100 per year that it is overdue. For example, if your instrument has been out three years, the charge will be $400.

Modifying or altering your XL in any way will void your warranty as well as the $200.00 repair offer. Slipmeters that have been "repaired" by your maintenance staff require an extra charge (of $200) to cover the extra labor and parts that are normally destroyed in the process. People who don't understand the high-pressure system design and do not have the special tools that I have made for assembly cannot make successful repairs. At least nobody has so far, that I can find out about. In cases of inadequate payment, I will hold the instruments until the proper amount is received.

If your XL has been adulterated by changing the pressure source from the pellet gun cylinder, I can't callibrate it for you. My charge for restoring an adulterated instrument is $600.00 in the US. International units will be higher.