FAS-t Cave Survey Device

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White Arrow has recently introduced some new cave diving and survey gear in the USA (they are an Italian company). I am not an employee and have never met the owners or others asscociated with the company.

I recently purchased the FAS-t from Dive Gear Express, the USA distributor. The FAS-t is a line measuring device with a mechanical counter and you can see it here:

http://youtu.be/ZYnkeIunzi0

In case you haven't bothered to view the video, the line wraps under/over/under three spindles with the middle spindle the one connected to a mechanical counter that counts in centimeters up to 9999 cm's (328 feet i think).

My problem was that this thing would not work reliably, the line kept slipping on the main spindle. The main spindle is covered in velcro (the hook part, not the fluffy part) and the velcro is replacable. But still line slips.

Turns out only cave line, the nylon stuff we typically use, is the problem. too thin. With gold line (what 1/4"?) and up to 5/16" there was no slipping. I was a bit dismayed and wondered if cave survey line would be have to be thicker from now on! by the way, knots in the line were no problem at all.

Then I slipped a rubber bicycle inner tube over the velcro and to my amazement the line no longer slipped on the spindle! #26 knotted and #30 knotted worked just fine. I repeated the test over 10 times and got the same reading every time, even with me pulling and pushing and turning and twisting the FAS-t in ways you wouldn't really do.

This weekend I plan to test this device against my tape measure in a local quarry (our caves are flooded out for now). I'll post the results, but I am confident the FAS-t with the rubber sleeve will now make line measuring one of the easiest jobs of cave survey!

The picture shows the velcro. I pulled it up a bit on the edge. It comes with extra velcro in case you need to replace it. But the rubber sleeve covers the velcro and eliminates all slippage, so that little fix is ideal. You can see in the video that different line tensions make a difference in handling, but with the rubber sleeve - no worries!

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[SLIM]

Can you try it with #18 line? Sounds likeit might be a good thing if it can work with the smallerline.

SLIM

[jlillest]

Cool, sounds like some good results. Now you just need to mount a compass and a depth gauge to it and you've got a complete survey package.

Would love to hear more after your quarry survey.

So, has the company said anything about MSRP for these little guys?

-Jon

[kmev]

What's the depth rating on the counter - is it oil filled?

[gschaut]

Did you check it for accuracy as well as reliability? Adding extra material might increase the diameter of the drum. As the device only counts shaft turns, a larger diameter drum would cause a slight false low reading. Your device "might" read 300' of line as only 290' or 280' of line.

You might have to calibrate the device, or come up with a correction factor to translate the "reading" into true line length.

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I do not know the depth rating or accuracy compared to other measures.

The counter is not oil filled. It is basic plastic, but very smooth operation. I'm pretty sure it's open to ambient pressure, no air-filled areas at all.

I did wonder about the extra diameter of the drum, but have not done the comparative tests. a math solution would not be bad, even if curvilinear. I don't see how the counter could be calibrated, but a conversion factor would be an easy solution. I see a table in my future.

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Can you try it with #18 line? Sounds likeit might be a good thing if it can work with the smallerline.

SLIM

#18? Dang Slim, that's pretty slim line! where do I get that?

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[kmev]

The counter is not oil filled. It is basic plastic, but very smooth operation. I'm pretty sure it's open to ambient pressure, no air-filled areas at all.

So it fills with water (and silt)? That won't last long.

[Line Squirrel]

Adding extra material might increase the diameter of the drum. As the device only counts shaft turns, a larger diameter drum would cause a slight false low reading. Your device "might" read 300' of line as only 290' or 280' of line.

Line dia. would not effect this.

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So it fills with water (and silt)? That won't last long.

time will tell, but I did my best to silt it out. I "dropped" it in the quarry silt, shook it all around, many times like a washing machine (entire area was silted out from my shennanigans) and no silt visible inside the counter (I rinsed it off so outside cleaned up). But the slow accumulation of gunk will still occur I'm pretty sure.

The counter is removable and replaceable. I have no idea what a new counter would cost, but the video shows how easy it is to remove and replace.

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