Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:
You can gain access to all this absolutely free when you register for an account, so sign up today!
This is from Italian forum, translated from member Saints Luke1:It appears from this photo that the vacuum seal is yellow and it was shown that way on the diagram above. My prediction is that it will soon be black as carbon black in rubber adds to its strength, abrasion and tear resistance, that is why automobile and truck tyres are black. Coloured rubber although hidden inside the gun muzzle will be subject to loading and pulling as the spear tail stop diameter blasts through it. Here the nose cap is unscrewed and we are looking at the vacuum seal or cuff from the rear.
View attachment 60111
Italians don't like the new piston..I watched the video right through, which is in Italian. The guy runs through all the features of the gun, then compares it to a Salvimar Predathor Vuoto pointing out the metal trigger, line release and high mount inner barrel of the Mares gun compared with the concentric inner barrel of the Salvimar gun. Later on he shows the Force gun in pieces. Most notable is that the alloy muzzle has an "O"ring on the rear end that seals inside the nose cone, usually guns have a seal on the inner barrel nose that backs onto the rear of the nose cone thus covering the tiny gap between nose cone and inner barrel. Possibly the Force gun has both as there is the usual plastic annulus just behind the screw thread on the inner barrel nose end that locates the "O" ring when you attach the nose cone and tighten up the muzzle.
The vacuum cuff is yellow as seen before. What Mares didn't do was use a plug in line slide to align the shaft before pushing on it to send the shaft tail through the vacuum seal, an omission also made by many others. If you plug in the line slide first then you minimize damage to the vacuum cuff, but for that you need a combined stop ring and line slide.
Spear tail to muzzle alignment pre the loading effort
We have seen that the vacuum muzzle production gun pioneer Taimen devoted a lot of effort into getting the shaft accurately placed in the muzzle before commencing the push onto the shaft into the gun. This consisted of a relatively long alignment by the line slide or slider which plugs into the...forums.deeperblue.com
I remembered that. That's why I put the quote.When the Cyrano Evo first appeared I made the comment that it seemed the work of those who had completely forgotten what the experienced men there had known for years, but was lost when they retired or died. Interesting to see this Italian author had the same thoughts.
Italians don't like the metal part with the O-ring on it. It is prone to corrosion. Many had problems with it.Pretty sure the new Force piston is machined in black delrin and the mushroom head metal tail with a rear "O" ring mounted in front of it with the conical wiper seal is screwed into the back end of the plastic. The front plastic body has a second "O" ring to keep water away from the metal tail, the annular recess in the piston body is intended for grease (don't bother). Single seal pistons are faster, but you don't want the piston to rock in the inner barrel. The previous all-molded Mares pistons may not have been up to vacuum barrel impacts, they have been made of various plastic types over the years, gradually getting worse.