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Slider

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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T

tromic

Well-Known Member
Aug 13, 2007
1,782
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This is my new slider for tomba equipped pneumatic gun, for the shaft without a butt. I have not tested it jet. I suppose it could work?




 
Wow, you are amazingly ingenious, I hope it does work?
 
foxfish said:
Wow, you are amazingly ingenious, I hope it does work?
Click to expand...

Thank you, foxfish, I hope too, it would work. If it will work it would be also very quiet. In combination with some hydro braking of the piston tomba equiped pneumatic gun could be the most quiet pneumatic gun, maybe more quiet than band guns. Tomba is made in plastic, slider too - there is no metal to metal friction or impact. I had seen the video about Omer Airbalete. Is'n it noisy? I think it is - because there is friction between metal slider end the shaft and also impact to the metal slider.
 
Hey Tromic, I have been thinking for a long time that a slider with flights might be a interesting experiment?
Something about 75mm long that has some form of plastic flight like a dart or arrow that will set a fast spin on the spear?
 
I think, I saw something similar recently... some Russian gun. I don't find it useful for short distances.
 
Thats a shame I thought you might make one, if you could find out more about the Russian version that would be great (or just make one as I am sure yours would be better)
 
The Russian pneumatic speargun sold as the "Prizm" in the West uses a tri-finned line slide, they refer to it as a "stabiliser". I think it does that more by virtue of moving the line pull to the rear of the spear as without it the line pulls from the front, that being where the line is tied, just behind the spear tip.

In the past people have tried using a sprung loaded, collet-type line slide to clamp onto an annular groove in the shaft tail, there being no line slide stop diameter enlargement as is the usual arrangement. The problem is the spear is moving so fast that the collet has little time to grab onto the shaft with the result that the spear shoots clean through it. One way to increase the chances of line slides catching onto a not very much larger than the spear diameter tail stop was to taper the shaft down at the rear end just before it merges into the tail stop, thus offering a larger area shoulder for the line slide to catch onto. The idea was the line slide was knocked off line and caught the step shoulder on one side because it was no longer concentric with the shaft and thereby increased its holding power if a fish was on the spear. These taper tailed spears seem to have disappeared in the interests of cost savings in spear manufacture.

You really need a distinct stepped edge for the line to grip onto the annular shoulder, otherwise the shaft will just pull through with any load on it imposed by a struggling fish. Any front leading curved edge to the shaft tail only requires the line itself to stretch slightly and it will pop off the end of the shaft.
 
I have tested both versions of slider with Cyrano 850, vacuum barrel, and 6,5 mm shaft.
Up to 25 bars both versions were working.
At 27 bars only the second (spring) version was working.
 
Good to hear that it stops the shaft, but have you checked the holding power against something pulling hard, like a struggling fish trying to escape?
 
popgun pete said:
Good to hear that it stops the shaft, but have you checked the holding power against something pulling hard, like a struggling fish trying to escape?
Click to expand...

No, I have not check the holding power of the slider yet. I suppose there would not be a problem with a fish up to few kgs. The problem is that the slider could become unreliable if it gets slimy (from the fish). I have tried to put some silicone on it. After that the slider did not stop in the grove on the shaft. Good friction is important. So I would not advise the use of the slider.
 
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The "knot slider". Very good in performance. Low drag. The knot is the Rolling Hitch with addition of an Overhand knot. To the left of the knot is 0.4 mm fishing line which serves to stop and tie the knot in the groove at the shaft.


I have not abandon the previous "spring slider" too. Just put stronger spring and it is working OK.
 
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