Does anyone have a 90cm Seac gun handy? I need help pronto...

[Diving Gecko]

Hey guys,
About to order some spears for a 90cm Seac Hunter (It's like a face lifted Asso). The spears will be ready-made freeshafts to go with a dry barrel modification.
But I am currently not in the same country as my gun and I need a measurement to make sure, I order the correct length of spear.
So if any of you have an Asso or Hunter handy and feel like helping out, then I'd be grateful.
Basically, I need to know how much of the spear is inside the gun when it is loaded. In other words, the length from the very bottom of the spear to right where it exits the muzzle. I know it is tricky unless you have a mostly "deflated" gun. I guess the easiest would be to measure the whole spear, top to bottom. Then load it and measure the overhang from tip of muzzle to tip of spear and subtract that from the total length of the spear. Or load it and mark the spear just where the muzzle tip is - then measure from that mark to bottom of spear.
(If you happen to have a modified muzzle as opposed to the stock muzzle, then I can still use the measurement, I just need to know what muzzle it is.)

Again, only if one of you have one handy and please don't jeopordize safety for my sake!

All best,
David

 

[kwtony]

exactly 31 inches of spear goes in to the gun, this is with a standard muzzle

 

[Diving Gecko]

Hi Kwtony,
Thanks sooo much. I hate to question your findings as you already went out of your way. But yesterday, I managed to get a hold of my friend who has my gun in storage and he came up with 32 inches. But he is not into spearing and might have gotten it wrong. Is yours an Asso or a Hunter? And it did postively click into the sear, right? (Not that I expect much difference). One inch might not sound like a lot, but the replacement freeshafts I am looking at are just either perfect, a tad too short or 5 inches too long. The freeshaft has a hole for the mono right behind the barb and if the spear is just an inch too short that hole might end up inside the muzzle which is no good. The good news is that your measurement is shorter which makes the risk of this smaller.

Best and thanks again,
D.

 

[kwtony]

Its okay, i understand your need for the exact numbers. Honestly tho, i still come up with 31 inches. I do have the seac asso 90cm or at least a rebranded version of it. The gun is getting its new dry barrel kit that just came in the mail yesterday and was all in pieces and deflated. I did have the piston in the gun and the stock muzzle on it. I checked two more times and its still got 31. I know it would be hard to get your buddy to check again, I think if your buddy measured 32 i would go with that number tho. Its more hassle if the spear is short then if its over by 1 inch.

 

[Diving Gecko]

Thanks so, so much for triple checking! Really appreciate it. I am waiting for the exact measurement on the spears from the shop (tail to hole behind barb) and then I'll order. Funny thing is my friend used to be a toolsmith and a woodworker, so he is good with these things. But perhaps, he didn't jam it in tight enough in the piston. Or perhaps, there really is an inch's difference between an Asso and a Hunter.
What dry kit did you get for your's?

 

[kwtony]

I got the basic kit for this gun from marko. Which consisits of the front part of the muzzle and the line slides. I have it now epoxied into the second half of my stock muzzle and its now undergoing the rest of the build. I was having a leak somewhere in the handle now that i cant put my finger on so i had to tear the gun apart again...

 

[Diving Gecko]

I really wanted a complete "nude" freeshaft with line attached to the very top of spear, but now reevaluating. Also, I would love to not have to lift the gun out of the water before loading it and I guess if you keep the stock muzzle and put a rubber tube on it, the water will escape through the old muzzle relief holes.
In regards to your leak, I actually had my Seac leak from the trigger pin from when I bought it. Just needed a new o-ring. No special tools needed (though I thought so at first). You can pull out the pin with a pair of pliers and then unscrew the bushing. More here (post 10 onwards):
http://forums.deeperblue.com/pneumatic-spearguns/95749-how-many-pump-strokes-asso-hunter-90-a.html

 

[kwtony]

yeah i fully rebuilt the gun and there isnt an old seal in the gun. I need to put it in a pool and pump to see exactly where it might be coming from. As of now i could only hear what i thought to be a leak. After pumping it 50 or 60 times the pressure in the gun never increased so I sprayed soapy water on the handle in hopes of finding it with no luck. I removed the pin and the trigger assembly and but still am having trouble trying to locate it. I spend about 20 minuets on it and fell asleep last night so hopefully today ill figure it out. I guess i will try to replace the seal with another one and keep my fingers crossed...

 

[zmajmr]

I really wanted a complete "nude" freeshaft with line attached to the very top of spear, but now reevaluating. Also, I would love to not have to lift the gun out of the water before loading it and I guess if you keep the stock muzzle and put a rubber tube on it, the water will escape through the old muzzle relief holes.
In regards to your leak, I actually had my Seac leak from the trigger pin from when I bought it. Just needed a new o-ring. No special tools needed (though I thought so at first). You can pull out the pin with a pair of pliers and then unscrew the bushing. More here (post 10 onwards):
http://forums.deeperblue.com/pneumatic-spearguns/95749-how-many-pump-strokes-asso-hunter-90-a.html

Stock muzzle do not have round profile, it has hexagonal profile so rubber tube will not close places with holes, you need to wrap duck tape or something else. I asked my father would it be good idea to make custom muzzle with only one hole over which would be rubber tube (it would have round profile and idea is to act like valve) , my father said it was not good for free shaft, you need to drain water, (it lasts only 2 seconds). If you do not drain water then there is amount of water in front of shock absorber, and when piston hits in shock absorber , he can not move forwards because of water, because shaft blocks water until spear completely fly out from adapter of kit (it might happen to plastic part from shock absorber to crack). At kit with sliders water can more easy escape from adapter in case of little water left in barrel. I hope you understand what is problem.

 

[Diving Gecko]

Stock muzzle do not have round profile, it has hexagonal profile so rubber tube will not close places with holes, you need to wrap duck tape or something else. I asked my father would it be good idea to make custom muzzle with only one hole over which would be rubber tube (it would have round profile and idea is to act like valve) , my father said it was not good for free shaft, you need to drain water, (it lasts only 2 seconds). If you do not drain water then there is amount of water in front of shock absorber, and when piston hits in shock absorber , he can not move forwards because of water, because shaft blocks water until spear completely fly out from adapter of kit (it might happen to plastic part from shock absorber to crack). At kit with sliders water can more easy escape from adapter in case of little water left in barrel. I hope you understand what is problem.

Hi Marko,
Thanks for explaining further. I totally understand the challenge. Also, about the shape of the Seac muzzles.
I trust emptying the barrel will only take a few seconds once one is used to it. But I live in a country where just having a speargun is illegal (China...), so will only go spearing on certain vacations. Hence, I just want things to be simple as I don't have much time to practice.
With the slider setup, does people still empty the barrel or not?

All best,
David

 

[Diving Gecko]

yeah i fully rebuilt the gun and there isnt an old seal in the gun. I need to put it in a pool and pump to see exactly where it might be coming from. As of now i could only hear what i thought to be a leak. After pumping it 50 or 60 times the pressure in the gun never increased so I sprayed soapy water on the handle in hopes of finding it with no luck. I removed the pin and the trigger assembly and but still am having trouble trying to locate it. I spend about 20 minuets on it and fell asleep last night so hopefully today ill figure it out. I guess i will try to replace the seal with another one and keep my fingers crossed...

Hi Kwtony,
Hope you found the leak.
Wondering about your rebuild - did you buy a full set of o-rings from Seac (I think I saw that listed on a parts list once) or do you happen to have/know the different sizes needed?
I would love to have a full spare set for traveling. As mention, I don't go spearing regularly but only on vacations where I would most likely be away from any authorized service facilities and also be away from "o-ring shops".

Best,
David

 

[zmajmr]

Hi Marko,
Thanks for explaining further. I totally understand the challenge. Also, about the shape of the Seac muzzles.
I trust emptying the barrel will only take a few seconds once one is used to it. But I live in a country where just having a speargun is illegal (China...), so will only go spearing on certain vacations. Hence, I just want things to be simple as I don't have much time to practice.
With the slider setup, does people still empty the barrel or not?

All best,
David

Yes they empty. You do not need to practice it is natural, lift up, put spear, lift down (and 2 seconds are gone).

 

[Diving Gecko]

Yes they empty. You do not need to practice it is natural, lift up, put spear, lift down (and 2 seconds are gone).

OK, so no difference in practical use on the emptying matter then.
(Still waiting for the shop to get back to me in regards to spear availability)

 

[trromic]

OK, so no difference in practical use on the emptying matter then.
(Still waiting for the shop to get back to me in regards to spear availability)

I am still working on developing this idea: http://forums.deeperblue.com/pneuma...mba-all-one-barrel-sealing-44.html#post898345
At the moment I don't see any other solution to load the gun with free shaft, vacuum barrel, under water, not emptying water from muzzle before loading.

 

[Diving Gecko]

Yup, I am following the development eagerly. As said, it might be a small thing, but I think it would be great if a "self-emptying muzzle" could be created. I for one, would love such a thing. If it has the hydrobrake and it allows even higher pressure or less recoil, then I think you have a winner.
I guess, this would also let you remove the damper completely or downsize it quite a bit - which I guess would give the piston a longer working length perhaps leading to a slight increase in power? Speaking of which, does the piston really have to be that long? Would it be possible to make one which is 10-30mm shorter?

BTW, If you are closing to a working design on an self draining muzzle, then I am all up for getting that over a normal Tomba. But I wont be the best tester as I wouldn't have much to compare it with.

Best,
David

 

[foxfish]

I must say that I have been using my free shaft Tomba kit on my Omer 90 for two years & have never emptied the barrel!! The gun still works fine as far as I can tell?

 

[trromic]

I must that I have been using my free shaft Tomba kit on my Omer 90 for two years & have never emptied the barrel!! The gun still works fine as far as I can tell?

It depends on the amount of water left in muzzle, angle of aiming and some other details. But its also good to know Foxfish, your experience! :friday

 

[Diving Gecko]

Hi Foxfish,
I wouldn't be surprised if you aren't the only one not emptying it. I don't doubt at all the reasons for doing it, but perhaps the piston seals are tight enough and in practical terms it is not an issue. Despite reading a ton of posts on dry barrels, the emptying part gets mentioned very little. So, either everyone just does it or a lot don't and have not encountered problems.

Foxfish, you have customized a lot of your guns, I have noticed, so I suspect you take them apart with no trouble. I guess the thing to look for would be water behind the piston, right Tromic? Did you ever have this on your dry guns Fox?

All best,
David

 

[kwtony]

I found the culprit to be in the trigger. The inner diameter of the o ring was actually too large and not making a seal. After replacing it still leaks, for some reason the part the trigger pin slides into is not making a full seal on the gun and it looks like the threads are striped. I wonder if i can seal it with an epoxy or superglue. i have a feeling i might need to buy a new handle tho. Which sucks because i made a sweet custom handle for the gun, hopefully it wont be damaged too much when i try to fit it on the new one. Ill order one along with a few new spears and hopefully this 90 cm will be killing fish soon.

 

[Diving Gecko]

I found the culprit to be in the trigger. The inner diameter of the o ring was actually too large and not making a seal. After replacing it still leaks, for some reason the part the trigger pin slides into is not making a full seal on the gun and it looks like the threads are striped. I wonder if i can seal it with an epoxy or superglue. i have a feeling i might need to buy a new handle tho. Which sucks because i made a sweet custom handle for the gun, hopefully it wont be damaged too much when i try to fit it on the new one. Ill order one along with a few new spears and hopefully this 90 cm will be killing fish soon.

Oh, sorry to hear this. I was really worried about that scenario as well, when I took mine apart.
Unless, the thread is so stripped that it can't even hold the bushing, which the pin goes through, in place, then it shouldn't be able to leak through the threads at all. No air should get to the threads if I remember the design correctly. What I do remember, is that if you over-tighten the bushing or if it is too loose, then the seal is not good. There is kind of a sweet spot. But I don't know how much pressure is on that bushing and if a slightly stripped thread will hold it in place.
An alternative to a new handle could possibly be to have Marko or someone else machine you a new bushing which is slightly bigger and rethread the handle. Then you can also have a new thinner pin made which will make the trigger nice and soft.