shrink tubing

[papa bear1]

This is probably a dumb question BUT here i go anyway!!!! Can you use shrink tubing on the serving?? I thought maybe somebody tried it and could tell me what happened If not / why Don't be too hard on me i embarras easily

[gerald strine]

That stuff is pretty soft the latch hooks would most likely cut it pretty fast and I think it would wear on the rail quickly also .

[Farmer]

I would cut pretty fast, not very flexible either . The serving also allows for a little grip on the rear nock / insert of the arrow shrink tube may allow it to skip over or under

[shafferm]

It is not a dumb question, the most common heat shrink tubing available at your local hardware store is most likely thin walled polyolefin. This stuff is a bit soft and unlikely to work for very long.

Something like a heavy walled PTFE (teflon) 2:1 shrink tubing would be much more suited to this. Sometimes it is referred to as dual wall. The obstacle to overcome with this would be getting it to shrink on without overheating the string to the point of weakening it where it may fail.

The shrink temperature for this is around 340 Celsius. I would soak the string and serving in water first, then use a flame to very rapidly shrink the tubing over the serving, and dunk back in cold water as soon as you are finished shrinking the tubing. This should limit the max temperature the string sees to 100 Celsius as the water boils off. I had also though about water soaking and freezing the string and serving to keep it even cooler during the shrinking process.

I would not be worried about lack of grip on the rear insert, the main issue for the string being able to skip over or under the insert is how far from the center of the insert the string is applying pressure. Usually it skips under from having strings with very low numbers of strands and using thin diameter serving material. Adding shrink tubing over a serving should help to move the string contact closer to the center of the rear insert.

The teflon shrink tubing is much more flexible than the polyolefin and may give a few fps increase as it would reduce friction along the rail.

It would be interesting to compare one string with the teflon tubing applied and one without to their breaking points. Tensile testing would quickly let you know how much the application of the shrink tubing degrades the string, if any.

I have thought about this for awhile now, haven't had the time to try to implement it. It would be interesting to see how well it works. I would highly recommend testing the string off the bow to a tension of around 300 pounds or so, with a spring scale and a come along winch, if it passes this test, then odds are it should be able to easily hold to the tension from the bow.

Let us know if you do give it a try.

[wabi]

I wouldn't try it.
Even if you get it installed without damaging the string it would increase the diameter of the serving which could cause problems with the string contacting the flat nock near the center. It could cause accuracy problems or even a dry-fire if it jumped over the nock.

[papa bear1]

Thank you everyone !!!! whewww. everything you have suguested make's sence ..... what i think i will do is NOT"" do it seem's there are too many varibles for me to figure out. But I appreciate all your input. Maybe somebody else will try it and post the results THANK'S

papa bear1

[Cossack]

Sounds like a good winter project BUT with serving being so easy to apply and so much fun, WHY? Certainly not any faster.

http://www.crossbow-review.com/TechCorner/Don_P1.htm

[Dash]

Its good to think outside the box, but Wabi is right about the string center being too low on the nock. Its risky shooting anything myself that didn't line up close with the nock center.
My feelings is that to apply the shrink could risk the string, and I'm not confident even quality shrink wrap would hold up either on this application.