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I haven't bought any Thera Tube rubber for a long time, as I mostly use the flat type. But the new launchers I recently made work well with tubing, and my stash was dwindling away quickly. <br><br>So I ordered some new silver, black and blue tubing. I put the silver on my Blunderbuss, and was immediately stunned by the stretchiness - and the speed of the shot. <br><br>I compared the old and new types, and the difference was totally obvious. The new tubing is much thinner. See the new and the old silver in comparison:<br><br><br><div style="margin:auto;text-align:center;width:100%"><a href="http://3.bp.blogspot.com/-gPyU3DtfEhc/UDCKjZz1DJI/AAAAAAAACCg/-3eCkZV4yk4/s1600/Tubesilver.JPG" class="postlink" target="_blank" rel="nofollow"><img src="http://3.bp.blogspot.com/-gPyU3DtfEhc/UDCKjZz1DJI/AAAAAAAACCg/-3eCkZV4yk4/s400/Tubesilver.JPG" border="0" alt=""></a></div>I weighed it, and the data confirmed the visual impression. The old silver tubes weigh 0,875 gramms per centimeter, the new type just 0,535 gramms - just 61%!<br><br>I measured the draw resistance, and it was identical (about 17 kg at full stretch). This means that the new tubing is 39% more efficient!<br><br>I then looked at the black type. The same thing! See the old and the new:<br><br><br><div style="margin:auto;text-align:center;width:100%"><a href="http://2.bp.blogspot.com/-SXZl1Y-blXw/UDCL1lkizZI/AAAAAAAACCo/Jb8JBB3FwH4/s1600/Black.JPG" class="postlink" target="_blank" rel="nofollow"><img src="http://2.bp.blogspot.com/-SXZl1Y-blXw/UDCL1lkizZI/AAAAAAAACCo/Jb8JBB3FwH4/s400/Black.JPG" border="0" alt=""></a></div>
<br><br>Same thing - the old type weighs 0,57 gramms per cm (actually more than the old silver), whereas the new black type is 0,43 gramms per cm only. 25% less! Same draw resistance (7,5 kg at full stretch). <br><br>I tested the weight of the flat type (Thera Band Black) and 0,49 gramms per cm. This means that the new tube is 12% lighter than the flat bands - which used to be 13% heavier! The weight ratio has been completely reversed. <br><br>I will do some chrony tests today. But my experiences so far have been very promising. Maybe we will see a comeback of tubular bands for performance oriented shooters. <br><br>Here is one more pic, the new silver compared to the old black:<br><br><br><br><div style="margin:auto;text-align:center;width:100%"><a href="http://4.bp.blogspot.com/-f_RfW23JckI/UDCNw00dCVI/AAAAAAAACCw/9D1s-8oSwIg/s1600/BlackSilver.JPG" class="postlink" target="_blank" rel="nofollow"><img src="http://4.bp.blogspot.com/-f_RfW23JckI/UDCNw00dCVI/AAAAAAAACCw/9D1s-8oSwIg/s400/BlackSilver.JPG" border="0" alt=""></a></div>
 

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<div>Cool</div><div class="clear"></div><div class="signature_div">
<br><strong>at school, I am a slingshot expert</strong> <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1"><br><br>on this forum a noob <img src="http://illiweb.com/fa/i/smiles/icon_neutral.gif" alt="Neutral" longdesc="20">
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Discussion Starter · #4 ·
Some tests today. Four candidates:<br><br>Old black tube<br>New black tube<br>Black flats untapered (whole width 13,8cm)<br>Black flats tapered 2,8X1,8, six layers per side (whole width altogether)<br><br>The flat bands have a lot more draw weight than the tubes.So I can not confirm the Hygenics statement that tubes and flats of the same color have the same draw.<br><br>The new black tubes seem to be very light. I had to shorten them to 25 cm total length for a full butterfly draw (6,28 times the relaxed length).<br><br>I shot 20 mm steel balls. <br><br>I achieved a max of 58 m/s with the tapered flat bands. Untapered flats got 54 m/s, then the new tubing (53 m/s) and the old tubes (47 m/s). <br><br>So the new tubes are certainly better than the old tubes. But they still do not reach the efficiency of tapered flat bands. In comparison with untapered flat bands, they work fine.
 

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LoL!<br>I bet Thera is selling>50% of their Products to Shooters around the world and i love that they start improving the Performance for those clients now <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1">
 

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Do you think there is a way to make tapered tubes?<br><br>I also wonder about making parrallel slits at different intervals in either bands or tubes to direct the forces mostly towards the vector axis of the shot. In the parallel slit idea you can use a untapered band in terms of its profile, but actually taper the force output using slits.
 

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Discussion Starter · #8 ·
Trumark sells tapered tubes, I think they use the dipping method which allows tapering. Their tubes are very good, but also expensive. <br><br>You can certainly cut away parts of an untapered tube to taper it. But then the advantage of tubing (long band life) will be gone. The tubes will stretch more (= heat up) at the tapered parts, making the shot faster - but they will tear at that spot just like flat bands.
 

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And what about using a hot-air-pistol and dragging them out? <br>Would that destroy the filaments?
 

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Discussion Starter · #10 ·
Rubber can't be de-vulcanized. That is the reason why we have whole yunkyards full of old tyres. Imagine the rubber could be melted and re-used!<br><br>But if you heat vulcanized rubber up, it simply disintegrates.
 

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The Chrony results are still pro Flatband <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1"> but nice to see they chance something maybe the make the Goldband strechy like the Black one day.
 

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Keep in mind, that Thera-Band has changed the width of their Exercise Bands product line from 13,8 cm to 12,8 cm some time ago. So you should take flatbands of corresponding width if you compare new tubes to flats.<br><br>And maybe this could be the reason of different draw weights and the minor speed differences concerning performance of black tubes and untapered flats in your experiment?
 

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<div>
<table width="90%" cellspacing="1" cellpadding="0" border="0" align="center">
<tr><td><span class="genmed"><b>Enoch1970 wrote:</b></span></td></tr>
<tr><td class="quote">Do you think there is a way to make tapered tubes?<br><br>I also wonder about making parrallel slits at different intervals in either bands or tubes to direct the forces mostly towards the vector axis of the shot. In the parallel slit idea you can use a untapered band in terms of its profile, but actually taper the force output using slits.</td></tr>
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<span class="postbody"><br><br>Use the cocktail setup on a single band instead of a double. Plenty fast!</span>
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<br>Failed perception is when you have a gun, I have a slingshot and you think you are the only one that is armed. <img src="http://illiweb.com/fa/i/smiles/icon_lol.gif" alt="Laughing" longdesc="7">
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Discussion Starter · #14 ·
<table width="90%" cellspacing="1" cellpadding="0" border="0" align="center">
<tr><td><span class="genmed"><b>spicy wrote:</b></span></td></tr>
<tr><td class="quote">Keep in mind, that Thera-Band has changed the width of their Exercise Bands product line from 13,8 cm to 12,8 cm some time ago. </td></tr>
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<span class="postbody"><br><br>I did not know that! Bought so much Thera Band a year ago (90 meters of Gold) that I still have plenty lying around. Hmm, time to order a sample - maybe the enhanced the flat rubber too!</span>
 

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@Jörg: <br>Where did you buy the new tubes? I am planing to make a small paintball bowlike slingshot with rope pulleys. Could you tell me the diameter of the tubes. <br>I was planning to use the old green ones with 8mm diameter and 22cm lenght.
 
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