Home Tournaments Calendar Weather Merchandise Sponsors

Go Back   Spearboard.com - The World's Largest Spearfishing Diving Boating Social Media Forum > Spearfishing Gear > All About Pole Spears & Slings

All About Pole Spears & Slings What is it about that traditional method of the early hunter/gatherers under the water? These devices are indeed interesting and effective.

Reply
 
Thread Tools Rate Thread Display Modes
Old 07-03-2017, 11:44 AM   #46
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Hi Aaron,
Thanks for the all rambling/info, much appreciated.
I did read some anecdotal evidence from you in old posts about designing and making stuff for spearos based in Japan. I think the most unique about the Japanese spears is the crazy length and lightness. I don't know how you guys and the guys before you designed your slip tips but I am still speculating that the Japanese tips might have come, or been inspired, from old dolphin/whale hand harpoons. To my untrained eyes, which don't have your experience, they look pretty different to what I have seen in the US.
Not sure about their rubber retaining system, though.

Here are some snaps of Japanese slip tips from one maker. There's a handful of guys making these but they all seem to be in the same style:





Anyways, I am making my spear very modular. Basically 3 pieces of ~3.6' poles and then the shaft plus a weight module. So, if the really long setup is too long for me, I can easily make a 7.2' version and if I add 1-2 weights it wont even be that lightweight.

BTW, what's the story with your merger...?;-)
And congrats, of course! Hope it'll work out well for you:-)

Last edited by Diving Gecko; 07-03-2017 at 12:45 PM.
Diving Gecko is offline   Reply With Quote
Old 07-03-2017, 11:57 AM   #47
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Made one more strap - this time a bit more simple as I left out the slider. The only other thing I changed was the little stainless steel tube that the wishbone dyneema attaches to.

Old strap at the top, new one on the bottom, it's pretty much as short as I can make it. I doubled up on the side where the resting hook is:


Instead of cutting off the top of the tube at the end to make space for the knot, as I did on the first one, I bored out the end on this one. There's no need to do this, really. But I just like my gear to look nice and tidy and hiding the knot a bit makes my OCD happy. (Well, my crib is rarely tidy but my gear is, haha):


Likewise, in the ever important aesthetics department, I managed to not mess up my binding rivets as badly this time - easy, just changed to some other pliers... (actually, since these rivets are, sadly, not stainless, but just nickel plated, it might help them last a bit longer):


The loop on the tag end of the wishbone dyneema is for the floatline to attach to. If this spear ever ends up in a big fish, the pull will go straight from the wishbone into the floatline, by-passing the strap. Not that it really matters - the strap will hold at least 80kg - not sure the rubber would hold that much:


I thought about running the dyneema through some PU tube so that it would be easier to clip onto the loop, but I might not use a tuna clip on my floatline. I am thinking just to use a sheet bend knot (what the Gannet guys calls...The Gannet Tie... Yup, branding is everything, haha). It's faster to tie than a bowline knot but like the bowline the sheet bend is super easy to untie even after having been loaded up (we actually used it on our spinnaker sheets, back when I raced sailboats). So far, in my rigging, I am trying to avoid any noisy metal hardware - after all, Ninjas do come from Japan;-). That said, I just remembered seeing pics of how some of the Japanese spearos place the hook on the inside of the strap and only have the very end, the hook itself, stick out. It could very well be to reduce or subdue any noise from the metal hook banging on the spear (might do that on Ultimate Ninja'ized Resting Hook V3):



In other news, I just got assigned (I am a photographer) to a story in Korea, though. And after I return, I'll only have a day or two before my Japan trip, so now the whole polespear project might not be finished in time. We will see. Perhaps I will end up gluing it all together in Japan. That is, if the metal parts actually arrive...

Last edited by Diving Gecko; 07-05-2017 at 07:28 PM.
Diving Gecko is offline   Reply With Quote
Old 07-03-2017, 12:10 PM   #48
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Quote:
Originally Posted by kavachi View Post
one of those gangster Okinawa GTs is gonna see that sexy carbon fiber and its going to be ON!!
Yeah... Thing is, I am not sure what I can do with a big GT on a small island when it's just me and the girl...

I have seen some pretty neat vids of local spearos taking big GTs (don't know how often it happens), but if I haven't made friends there when that fish swims by me, I will have to let it go. I don't want to walk out of the ocean with a huge Ronin Aji - coolest name ever for a fish, right - and go: "Uh, so... what now?"

Hopefully, there's other good sashimi swimming around in smaller sizes, too.
Diving Gecko is offline   Reply With Quote
Old 07-10-2017, 07:48 AM   #49
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Came home from my Korea assignment just now to find my connectors sitting outside my door.



They are a bit rough around the edges and don't have all the features I had drawn up. E.g. no set screw for the shaft nor a groove for a breakaway shooting line at the rear end. The machinist was pressed for time. But that's OK, these will suffice for now:-)

I have one more set of these but may not get more CF tubes in time. But at least I have enough parts for one full 3-part spear.
Next up is prepping these and the tubes for gluing. And whipping up some dyneema lanyards.

Last edited by Diving Gecko; 07-10-2017 at 07:57 AM.
Diving Gecko is offline   Reply With Quote
Old 07-10-2017, 08:52 PM   #50
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Prepped the connectors by roughing up and degreasing the glue surfaces. Then spliced the 3mm dyneema lanyard onto them (the other end will be tied):


I don't have any pics of when I glued in the first three connectors, but I used a two-part structural epoxy from 3M. I'll snap a pic later on.

Here's the "other" end of the poles with the tag line of the dyneema being tied to the connectors that have not yet been glued in place. The bowline knot will loose roughly about 40% of the breaking strength but with a heavy 3mm dyneema that's not an issue at all. I super-glued the knot, too which has proven to stop it from slipping:


[EDIT]
Here's the 'missing pic' of glueing in a connector:


The glue is 3M DP460 but I could probably just as well have made my own thickened epoxy. It was just easier using the 3M glue for the smaller batches I had to mix up a handful of times as I did not glue it all in in one go. I glued connectors on one end of each pole and once they had set, I glued in the connector on the adjacent pole and screwed the two poles together and then them to a long piece of 90 degree alu profile that works as a straight edge (no pics of that).

Last edited by Diving Gecko; 07-12-2017 at 03:47 AM.
Diving Gecko is offline   Reply With Quote
Old 07-12-2017, 10:40 PM   #51
Linghunt
Registered User
 
Linghunt's Avatar
 
Join Date: Mar 2006
Location: Santa Rosa
Posts: 256
Send a message via Skype™ to Linghunt
Re: Help Needed, DIY Jap Style Polespear

300 g ~ 11 oz. Must be aluminum.

Did you consider a surface finish? Glad to see you got parts done finally.

What is long rod for , counter weight?
__________________
Later on -- keep your powder dry--
Linghunt is offline   Reply With Quote
Old 07-13-2017, 12:46 AM   #52
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

It's steel, but they are just pretty tiny. The longer ones are indeed solid weights, just to have a bit more punch, if needed. Though we will see how well it works in real life.


Sent from my iPhone using Tapatalk
Diving Gecko is offline   Reply With Quote
Old 07-18-2017, 02:35 AM   #53
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

A quick note on my slip tip rigging. I went with pretty much the same method as Headhunter (which, again, I think is lifted from the Japanese spearos) except I eliminated the wire loop Headhunter use. The slip tip is a Spearmaster, the shaft is 7mm titanium rod and I eye spliced both ends of the 2.5mm dyneema shooting line. The yellow rubber band, which keeps tension on the slip tip so it stays on the shaft, will be secured in a different way on the pole, not sure how yet. The front of the rubber band where it is looped through the small figure-eight stainless fitting is just super glued together. We will see how that holds up.





The idea with this type of rigging is that you can easily separate the whole slip tip (with the dyneema) from the polespear in case it's too much of a hassle threading the slip tip back through the fish to get it out. Instead, you just pull the dyneema line through the fish. I guess harder to explain here than to do in real life;-)

[EDIT]
A quick video here to show what may not have been made clear in the sentence above;-)

Last edited by Diving Gecko; 07-18-2017 at 03:12 AM.
Diving Gecko is offline   Reply With Quote
Old 07-18-2017, 08:39 PM   #54
Seadive1
Registered User
 
Join Date: Jan 2014
Location: Miami, FL.
Posts: 107
Re: Help Needed, DIY Jap Style Polespear

Mr gecko, you did a hell of a job there. If you don't mind me asking, did you have you parts CNCed on a website? We're they expensive?

Love the whole design/outcome, bravo.


Sent from my iPhone using Tapatalk
Seadive1 is offline   Reply With Quote
Old 07-19-2017, 03:08 AM   #55
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Thanks so much:-). I called in a favor from a local friend here in China who then called in another favor. But in the end, I think we did get charged. But it was affordable. Not all of it was CNC'd, though. E.g. the flanges are manually milled and threads, too I think. Most of the tolerances are good but the flanges are a tad oversized. Nothing that can't be dealt with if I go forward with a V2;-).

Overall, I spent quite a bit of time soaking up everything I could here and elsewhere on the web and had some great input from Linghunt and Aaron, too.


Sent from my iPhone using Tapatalk
Diving Gecko is offline   Reply With Quote
Old 07-19-2017, 11:52 AM   #56
Linghunt
Registered User
 
Linghunt's Avatar
 
Join Date: Mar 2006
Location: Santa Rosa
Posts: 256
Send a message via Skype™ to Linghunt
Re: Help Needed, DIY Jap Style Polespear

You did a bang up job on it. Folks looking at final design might not realize just how much time you spend on the design aspect of it.

The parts are all typical CNC without much fancy programming. CNC's are cost effective when one wants volume. Making a couple parts makes it not practical thusly why the friend approach and horse trading made it possible.

Look forward to seeing the results from water testing.

The Loop and Cross hole rigging is done by a few. Henley, Headhunter, Neritic come to mind. Aaron would know for sure, but roots might be Japan as you mentioned earlier.
__________________
Later on -- keep your powder dry--
Linghunt is offline   Reply With Quote
Old 07-20-2017, 03:00 AM   #57
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

Quote:
Originally Posted by Linghunt View Post
You did a bang up job on it. Folks looking at final design might not realize just how much time you spend on the design aspect of it.

The parts are all typical CNC without much fancy programming. CNC's are cost effective when one wants volume. Making a couple parts makes it not practical thusly why the friend approach and horse trading made it possible.

Look forward to seeing the results from water testing.

The Loop and Cross hole rigging is done by a few. Henley, Headhunter, Neritic come to mind. Aaron would know for sure, but roots might be Japan as you mentioned earlier.
Thanks so much, John. And thanks for taking the time and sharing tips and good, constructive criticism on this project:-).

Traveling through Japan right now and lugging way too many bags (camera gear, freedive fins bag, backpack) plus a suitcase I am pretty sure the next spear will have elements no longer than that of a fin. That way, I can eliminate one bag and have the polespear in my fin bag. I think I wanted that originally but got carried away once I got my hand on 4' sections of the CF tubes.

I should be able to get in the water in the next week or two with these spears
Diving Gecko is offline   Reply With Quote
Old 07-28-2017, 02:04 AM   #58
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

No fish yet, only had two water sessions and not knowing the spots here, I am kinda swimming blind. Turns out, the two places we hit, were very shallow. Pretty though;-).

As for the hunting, I did miss on two parrotfish, though so will still take some time to get used to aiming this thing. At least, I think I was closer on the second shot;-). Also, a grouper kept outsmarting me from cave to cave. Did spot it a handful of times, but the lack of confidence in my aim meant, I didn't go for the shot.
But I did see some nice marine life; banded sea snakes, turtle, ray and the biggest trigger I've ever seen. And of course, two mullets swam right past me in the shallows as I had just disassembled the spear to get out of the water, haha.

The second spot held more baby groupers than I have seen in all my previous dives in Philippines and Thailand. So, there's gotta be some bigger ones somewhere else. Also, some of the surgeonfish here are massive. Supposedly, good eating, too. As for pelagics, I just came across two pan sized blue trevallies but they kept their distance, too.

With only two sections and a regular flopper shaft:


Three sections of about 4 feet each:




It's cool to get to try it out and get to know it's gremlins;-). More on that later.

Last edited by Diving Gecko; 07-28-2017 at 02:59 AM.
Diving Gecko is offline   Reply With Quote
Old 07-31-2017, 04:45 PM   #59
Linghunt
Registered User
 
Linghunt's Avatar
 
Join Date: Mar 2006
Location: Santa Rosa
Posts: 256
Send a message via Skype™ to Linghunt
Re: Help Needed, DIY Jap Style Polespear

Set up a target and do some practice shots. A ring on a float or something can be put together. I made a small square PVC target. I tied a couple weights on the bottom and set it on the bottom of a deep river hole for practice.

Aim small miss small...

Shoot a super small fish long ago in practice mode. I remember hitting one that was like 2 inches or so. I put it on my dive buddies stringer for him. Pretty funny, but he didn't think so.
__________________
Later on -- keep your powder dry--
Linghunt is offline   Reply With Quote
Old 08-03-2017, 12:36 AM   #60
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 679
Re: Help Needed, DIY Jap Style Polespear

A slightly sad update...
Ran out of time in Okinawa and only ever got three sessions in in shallow water. Also, Oki might have changed their regulations this year. It used to be that polespears were OK, guns not, but now, rumor had it nothing was OK without a fishing license (which is impossible for visitors to get). In the end, I hung out with some very good freediving friends of mine instead (no spearing) so did get some OK dives in.
I am back home in Shanghai now but I'll try to look into the regulations in Japan and share that info in the right threads if I get it.

Getting skunked like this hurts, especially because I have a feeling there's gotta be good spots and proper fish there and would have been amazing having that as close geographically to me as Okinawa actually is. But at least I did learn a few things about the set up:
  • I rigged the spear without any swivels, shackles or other metal hardware and honestly, it was not an issue at all. I don't see much reason to add any. There is a slip knot at the front end of the band and a loop at the read, so everything can still be taken apart easily
  • The rear of the rest hook is very prone to ripping up the rubber grip when I hook it in and let it slide back on the grip until it is firmly catching on and resting. The easy solution to that is to place the hook on the inside of the strap and only letting the very front of it pop through a hole in the strap (it's the rear of the hook plate doing the damage, not the hook itself)
  • Having the resting hook attach to a dyneema loop is not the best solution as the loop tends not to stay in the same place and can be hard to hook into. It becomes a more fiddly operation than it should be. A metal fitting which stay in place on the spear (also used by Japanese spearos) will likely be on my next spear. For now, the dyneema is fine until I identifiy the exact place I want to locate a metal fitting.
  • My next version of this spear will have sections which are no longer than a set of freediving fins as it would be great to be able to carry everything in just a fin backpack
  • The connectors would have been fine without the flanges for wrenches. I never actually used the wrenches, I just hand-tightened the sections and there was no slop, nor did they come loose during the dives. For now, I don't feel the connectors would be a weak link so I wouldn't mind making each section shorter which, for the longest setup, would mean four sections instead of three and thus, more connectors
  • The spear is pretty light in the water and the weight of it not really noticeable when swimming with it. With the 7mm, 20' flopper shaft the center of gravity is a bit in front of the hand strap/grip point. So, for longer swims when I tried to get to the end of the shallow reeds and find the wall (never did) I would just move my hand out of the strap (the resting hook keeps the spear loaded) and hold the spear further forward. Then it was super nicely balanced
  • I didn't notice any flex of the spear with 19.3kg/42.5 lb of pull on the shorter 2-section setup even the few times I forgot the half turn. Though it is not a super strong pull I could feel some wrist pain (from the loading) in my forward hand, rather than the hand I held the band with. Hopefully with more practice/exercise that issue will go away
I'll add more points as I remember them...

A few frame grabs from the second testing "swim" on one of the shallow spots. Spear is rigged with two out of three sections (8 feet spear + 20 inches flopper shaft), 13mm Small ID rubber @3.75 stretch ratio (42lb of pull) and grip placement 65% up the polespear:





Last edited by Diving Gecko; 08-13-2017 at 12:31 PM.
Diving Gecko is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:53 AM.


The World's Largest Spearfishing Diving Social Media Forum Powered by vBulletin® Version 3.8.1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright ©2002 - 2014 Spearboard.com