European screw-on wishbones - 16mm v. 18mm v. 20mm - Omer v. Picasso v. ....

[Mr. X]

"The time has come, the Walrus said, to speak of many things. Of ships and shoes and sealing wax, of cabbages and kings. Of why the sea is boiling hot, and whether pigs have wings." - Lewis Carol​

I was looking for simple way to convert my Omer XXVs metal articulated wishbones to soft, safe, quiet dyneema, using the existing rubbers. I came across some screw-on Picasso Dyneema wishbones at www.dkbunderwatersports.co.uk at a reasonable price and thought I give them a try.

http://www.austins.com/spearfishingaccessories.aspx

Unfortunately, the Picasso wishbones don't screw on to the Omer rubbers dis-a-ppointed! I wondered if anyone knows why? I thought the euro-rubbers were fairly (but not completely) standardized. It occurred to me that it might be because the Omer XXV has 18mm rubbers and the Picasso wishbones are probably intended for 16mm rubbers. However, I just checked the Omer website and while they do have different diameter wishbones, they only offer 16 & 20mm. I guess the Omer 18mm rubbers might be fitted with the 20mm wishbone rather than the 16mm one - but the Picasso connectors seem about the same size & diameter as the Omer. The threads don't mesh well though, so I wondered if different companies are using different threads? To me, it seems like the Picasso connections might have a coarser thread than the Omers'.

I can probably dismantled boths sets of wishbones & move the dyneema cord over to the Omer connectors (although the hole in the top is a little bigger than ideal). Although I was planning to order some bulk-rubber & dyneema for next season, so maybe I need to get on that.

 

[alexrom1207]

Ever since I found out that you can buy the euro adapters that fit into a screw on muzzle and then just use bulk rubber, I've given up on paying the ridiculous prices for the euro bands and wishbones. I paid $37 for a pair of bands for a 55cm sporasub, and the articulated wishbone (only one the dive shop had) was an additional $30. I could have bought enough bulk rubber and dynema to get me through 5 seasons for that amount.

 

[Mr. X]

Yes, I agree, I plan to move to bulk rubber & dyneema next year but figured my existing bands still have plenty of life left in them. I probably won't use muzzle adapters though (although that is an interesting idea - if not having a rail turns out to be an issue:hmm). A single continuous band is simpler & brings several extra cms of rubber into play (RA reckon their bulk rubber muzzles take an extra 10cm of rubber -- significant).

 

[Lazuli]

Dyneema is the way forward. My cayman came with an 18mm circular sling with screw-on bridle. The barrel soon started to get chipped from the metal wishbone. I took off the wishbone, cut off the screw caps with a kitchen knife, went to Subprof and got a dyneema wishbone kit and a reel of 1.5mm Dyneforce line, tied my own and have never looked back. The gun is really quiet and I have tweaked a lot more power out of the bands.

The OMER 18mm bands do have a whopping hollow middle running through them. I was quite surprised, but I do rate their rubbers. I get a lot of range out of my 75 having shortened the band a bit.

I like the eyed beads that you tie in to the bands. You can then sheet-bend some 2mm dyneema rope on them to form the wishbone / bridle. If it frays you can just replace it without cutting the constrictor knots on the bands etc. Good if you need to replace the wishbone on the go. The beads will last a lifetime.

 

[Mr. X]

Having fixed loops definitely has advantages. Pastor posted some pictures of this a while back. I might give that a try - although I have some RA toggles, so might just use them, clean, simple, light & low profile. Those metal or plastic toggle things with ends that stick out for tying into look interesting. Stainless steel ones (like Rabitech's) look cool - but I reckon I would go for plastic (like Orca's) as they should be lighter & quieter, although maybe cord loops is the way to go:hmm.

I've just finished dismantling my Omer wishbones & inserted my Picasso cord & washers. I knotted the ends with a "surgeon-style" double-overhand knot, as that was what Picasso (and Rob Allen) use. [Anybody need Picasso end-caps or the metal parts for two Omer French Articulate wishbone?]. I must say I felt happier as soon as I screwed them on. My super-light XXVs are now even lighter, sleeker, quieter ... and safer. I'll be able to wear my new gloves again -- I'd switched back to my old, thicker, cut-up, worn out gloves when I started dealing with the metal wishbones. BTW the cord on mine is black (unlike the picture above), which although quite "stealth" looks a lot like my black spear-line and black bungee cord -- which might complicate tangles (TBD).

 

[Lazuli]

Having loops tied in is very handy and if they are dyneema or metal they'll probably last the life of the bands (if you don't go on to shorten later or have some mishap). I have tried 3 types of dyneema: 1.5mm braid, 1.8mm rope, and 2mm rope. With the 6.3mm Omer ss spears with recessed barb that I use, I find the 2mm dyneema rope the most suitable due to the rope's outer sheath which protects the inner core from abrasion; and the snug fit.

I go the whole hog with filing and grinding spear notches to make them smooth using CHEMCO (fine and coarse) valve paste (cheap stuff too). So far I have had few problems with wishbone fraying.

My experiments with 1.5mm Dyneema braid (dyneforce) as a wishbone material were unsuccessful. Firstly the waxy coating increased slippage of the wishbone under tension, and this often led to cuts and frays if it slipped out of the notch.

It would be interesting to obtain some really fresh bands that have not sat in-store for ages. I'd like to try some fresh amber 18mm latex next time. Any recommendations?

 

[spaghetti]

Compatability does not have to do with the thickness of the rubber, but with the step of the threads. Talking in general, Picasso and Cressi threads don't fit in Omer threads. All the other brands are quite compatable.
Mr. X look at this Merou wishbone (screw on wishbone made of braided stainless steel, 2millimeters thick AISI 316 steel, with thread thingies made of fiberglass reinforced nylon). It won't shave your precious carbon barrel as much as an articulated wishbone!
http://www.merou.it/index.php?page=...category_id=2&option=com_virtuemart&Itemid=50
..

 

[cmburch]

I have had the same problem with Picasso Dyneema obus and Mares. The threading is the same, but the ridges and valleys on the threading must be slightly different. The Mares will fit almost everything while the Picasso is limited.

I am using Mako SS Dyneema inserts. They are easy to install on bulk rubber and easy to change or adjust the Dyneema. I do not bevel the ends of my bands.

MAKO Spearguns - Instructional Info

Picasso also has some black inserts for tying Dyneema to. I will try these out later.

 

[Mr. X]

Thanks for the input guys. Spaghetti I did read somebody comment that the wire wishbones can fray, which is not so nice for the fingers - I think RA offer them too though but most people go for dyneema. So Omer has the more normal thread? BTW The Omer end-cap are nicer (soft, thick plastic) than the Picasso end caps (shiney, hard/brittle plastic).

My diving at the weekend marred by some equipment problems . My newly repair Omer mask started leaking again And I was unable to load my Omer XXV 75 to the last notch because the new Dyneema wishbone would not stay in the notch! I eventually managed to load to the first notch but the dyneema's grip was precarious and extreme caution was required. When I loaded it a second time I could feel a tendon pop in the back of my hand (wince) as I tried to hold back the bands while simultaneously gently removing my finger tips so as not to release the wishbone's tenuous grip on the notch -- painful & the back of my hand has swollen up (all those years of climbing somehow without damaging finger tendons and now this!).:crutch It's been a bad year for injuries & illness.

I caught glimpses of a couple of small-ish bass hiding in weed & 3 small-ish mullet travelling together at speed. A larger mullet had the audacity to swim over my head as I did a (very) shallow water aspetto in about 4 foot (1.5m) of water! The only fish to come near enough, long enough to shoot was a tiny, barely legal size bass, the smallest bass I think I have ever seen - which I had no interest in taking. But it's always nice to see bass & mullet. Lots of tiny wrasse about (often paired up with a spider crab, strangely), one big one & a couple of medium size ones. Not as fishy as it sounds though - quite disappointing really.

I think the Omer XXV is more precisely engineered than I anticipated. The bands seem ever so slightly higher than, say, my RA railgun's, presumably to work with the French articulated wishbone. The bands seem to be lifting the Dyneema out of the notch (the old metal wishbone would just dig itself in). Of course the notches in the spear are also too shallow - I'll need to make them deeper somehow (suggestions welcome) - which is perhaps the main problem. I wonder if removing the plastic bar which sets the height of the XXV's metal muzzle "wishbone" might help lower the bands slightly(?).

Meantime, Plan B, I put in my order for bulk rubber to SpearIt in the USA (I was unable to source it in the UK, it's made in the USA and it's cheaper & easier to buy it direct from there): 19mm, 16mm and 14mm bulk rubber for making bands, 1.9mm Dyneema and some nickel/brass beads for making wishbones, some 3mm dyneema to make looped beads later and some kevlar contrictor cord (normally whipping cord is plenty strong enough but wanted something a little softer & wider so as to not cut into the rubber - kevlar strength seems unnecessary but the price was ok & the other attributes look good). Not sure if/how I'll use the 14mm rubber - perhaps as a pair or an asymmetric pairing with a 16mm band. We'll see.

 

[Lazuli]

Maybe in-line bands and dyneema exert a slight upward pull in the notch. Could be better running a sling through the front of the muzzle (when you get the bulk rubber) to change the pull angle toward the base of the muzzle (through the spear rather than parallel to it). Sorry to hear about your hand. An ex climber I know has a similar problem with a tendon in his hand.

3mm Dyneema will make some bomber beads for sure.

The whole constrictor cord thing makes me laugh. The constrictor knot is a harsh knot whether you tie it with garden twine, para cord, dyneema, kevlar or a boot lace. Subprof sent me monofilament fishing (aka "constrictor cord") line in the kit they sell and I threw it straight in the bin opting to use 1.5mm dyneema braid to tie in the beads instead. Nothing short of armageddon will undo the tension of the knot inadvertently and the cord is thick enough to be gentle on the rubber. Once properly constricted, neither the bead or the knot is slipping anywhere.

Dyneema is supposedly better than Kevlar (so I read somewhere), and they are making ballistic armour out of dyneema.

 

[Mr. X]

Yes Lazuli, that's what I was thinking - the bulk rubber will tend to pull down into the notch. However, that might bring its own problems -- my XXVs don't have rails. I wonder if the Dyneema pulling down into the spear is the reason that the S. African's manufacturers opted to fit rails? If necessary, I could fit stick on rails - but would rather not.

I've broken the long, slim Dremel-tool style grinding bit that I used to smooth out my spear grooves, so I need to find something to make the notches a tad longer. My needle files seem a bit big and not really up to cutting into stainless steel. I just came across these diamond-coated needle files - I have something similar for sharpening my dive knife & that seems to work quite well:

Diamond Needle Files 140mm Set of 10

Diamond Needle Files Set of 5

Diamond Cone File Pocket Version

Diamond Rifler Files 10Pc Set

Or maybe I should just buy a couple of spears intended for Dyneema wishbones (Picasso/RA)?

Switching back to the French articulated wishbones still an option of course .

 

[Mr. X]

Interesting related thread: http://forums.deeperblue.com/euro-s...version-picasso-carbontitanio.html#post773389

By the way, this is the company I ordered my parts from, seem to specialise in just the bits & pieces I am interested in: SpearIt for bulk rubber & wishbones dyneema, beads, constrictor braid, etc.: eBay Store - Spearit-Company: 1 2 13mm w S.Steel wishbones, SHOCKCORDS LINE, 9 16 14mm w S.Steel wishbone

But now I see they have their own website (it's considerably cheaper for Dyneema too!) AND they also sell the elusive Stainless Threaded adapters for Euro-guns. & stainless wishbone inserts - doh! Although they claim they'll work for Picasso AND Omer - which as we now know is very unlikely (they suggest 2 pairs to allow you to keep using your euro-wishbone):

Spearitco.com, The worlds largest selection of Speargun Bands and Do-It-Yourself Spearfishing Supplies​

Interesting link on tying Dyneema wishbones: http://www.spearitco.com/index.php?main_page=page&id=17&zenid=f33fad297afb754ba8075b0e9c3650f3
They also have links on tying bands & storing rubber.

 

[spaghetti]

Thanks for the input guys. Spaghetti I did read somebody comment that the wire wishbones can fray, which is not so nice for the fingers - .

Single wire certainly do dangerously split, but the Merou one is braided wires and won't snap.
Anyway, for the fingers, I think we should never load our spearguns without gloves (I've learned that the hard way :crutch....)

 

[Mr. X]

Braided wire, cool.

Wishbones hurt with gloves on too but I guess they offer some protectection - the French articulated wishbones cut through my old gloves like a knife. I'd like kevlar (or similar) reinforced gloves to protect against such injuries but, although available, I haven't seen any that are really good enough (e.g. close fitting) or cheap enough for spearfishing yet.

BTW I tried loading Italian-style from my abs. just above my belt to see if that might help (as holding the bands thumbs up seemed like it might allow me to remove my finger-tips more readily) but I just could get the bands back far enough -- needs some practice. I had my extra-loading pad on, so chest loading seemed like the easier option. I wonder if the Italian-style ab-loading works better with metal wishbones (easier to remove finger tips) and the SA-style chest loading works better with finger-friendly dyneema wishbones?

 

[Lazuli]

Interesting link on tying beads.

Bog standard needle files work fine. The secret is in the valve grinding paste . Ive done 3 spears with cheap files off ebay and Chemco grinding paste and all are fine. The secret is to get rid of burrs and edges around the notch with the files, then polish it with the fine paste. It does not have to be totally ergonomic as the dyneema/spectra/antline etc is pretty tough. I've never even come close to fraying through a wishbone yet.

Mmm? The rail question is a hard one. I fitted an omer rail to my Sioux 60 and it has held up extraordinarily well. A good bit of kit. In fact I am thinking of getting a new muzzle that will take slings so that I can use a bulk rubber open muzzle on my 60 (I love modding the Cressi Sioux - I reckon its the Sten or Kalashnikov of Speargunsrofl).

IMHO a speargun, when fitted with cord wishbones and an open muzzle, fires more like a crossbow underwater and feels less of a contraption.

 

[Mr. X]

Some interesting insights Lazuli.

I didn't feel like paying $6+ shipping on the diamond coated needle files and wanted to get on with the job, so I retried my cheapo needle files. Unfortunately I had filed the teeth off the most appropriate file - a round needle file - last year when I tried to make an iki jimi (dispatch) spike from it

Anyway, it occurred to me that a mini-hack saw might work better. It did. Then it occurred to me that a full size hacksaw might make a broader groove. It did. So that's did the coarse re-shaping. I did the best I could with the other needle files but will likely need to buy a new round file to finish it off properly and/or grinding tool for the "Dremel" mini-drill - about £1 from the local market.

Interesting what you said about valve grinding paste. The local hardware store sells 2 grades of grinding paste - presumably coarse is the way to go? I originally had an old but unused tube of Autosolv (chrome cleaner -probably the worse thing you could use on chrome) - as recommended by Ron's Corner - but can't locate it at the moment.

The notches are a lot more positive now. But I was still concerned about the bands pulling up, so I removed the plastic rod "bottom-stop" (part Z in the Omer XXV muzzle instructions) to allow them to sit naturally lower. Seems to work a treat. I dry loaded :naughty it, at the bottom of a long, clear run of garden, with spear-line & bungee re-attached (just in case) and the Dyneema wishbone seems to sit pretty comfortably now. I must say, it does not look a cool & perky as when equipped as Omer intended - the muzzle-end rubber caps droop down a tad. Also, the Dyneema wishbone's outer sheath wore right through (most of the damage was done with the shallow notches at the weekend), exposing the white braided inner core. I normally replace my RA wishbones when that happens.

I'm thinking I'll probably go full bulk rubber & open muzzle on the 75 when my order shows up but will revert the 90 back to metal wishbone for the time being. It has hardly been used and I don't want to experiment on 2 guns at the same time -- too many variables.

BTW My first RA wishbone lasted a couple of years but when I changed rubbers I went through 2 Dyneema wishbones almost immediately -- the cause turned out to be asymmetrical placement of the band in the muzzle (the new 20mm band is wedged in much tighter than a 16mm band, so getting the bands extactly even is apparently of considerable importance).

 

[Lazuli]

Hi X,
I bought some grinding paste which came in fine and coarse grades in a double ended pot. I file, then use coarse, finishing off with the fine grade. The fine grade is better as it does not abrade the polishing string so much.

Sounds like reverting the 90 back to a metal wishbone would be a wise move.

 

[Mr. X]

None of the small local hardware stores carried the things I needed, so I took a longer trip to the local market - had hoped to avoid the 32 mile round trip but it paid off. I got: a new large set of mini-needle files but much better yet I got a set of 5 sub-mini diamond needle files (only £3.50), small pot grinding "paste", small pot polishing "paste" and a large and varied set of diamond coated bits from my Dremel-style tool (suggested by the stall owner).

I used the round & semi-round diamond-coated files to shape & smooth the spear grooves. Then I used the grinding paste, followed by the polish smeared on lengths of cotton string to finish off. Looks good. Thanks for the tip Lazuli

As the outside protective sheath had gone, I switch wishbones with the 90 & converted the XXV 90cm speargun back to the original Omer metal French articulated wishbone. I got the impression the fish saw the end of my speargun last time out. So I put some black electricians tape of the 2 logos/stickers on the barrel, and on parts of the white handle not covered by my hand. I also marked up the shiney silver spear with permanent back marker but can't see that lasting long. The natural drab brown colouring of the RA spears is much less visible - but they need more care.

 

[Lazuli]

Hi X, glad to hear the goodies arrived safely from Spearit. Now the fun begins!!
Saw your post on the cornwall thread. My OMER Cayman Carbon 75 has a full length rail running from the mechanism to the end of the muzzle. Not easy to discern in the picture I posted.

 

[Mr. X]

Just need the weather now Lazuli. I'm currently using the hybrid solution: screw-in bands with dyneema wishbone but I anticipate getting peeved with that and moving to full bulk rubber solution pretty quickly.

Compatability does not have to do with the thickness of the rubber, but with the step of the threads. Talking in general, Picasso and Cressi threads don't fit in Omer threads. All the other brands are quite compatable....

Spaghetti, the main reason for posting, I have a question for you (and/or other forum members). This screw-in adaptor:

Stainless Threaded Adapter (Pair) to makeEuro Speargun Bands Stainless Threaded Adapter (Pair) to makeEuro Speargun Bands : Spearitco.com, The worlds largest selection of Speargun Bands and Do-It-Yourself Spearfishing Supplies

... claims to work with "Cressi, Beauchat, Picasso, Omer, Mares, Spetton Demka and many more". Surely that can't be true, as my new Picasso wishbones won't fit my Omer XXV 18mm rubbers (or is it just the Omer XXV 18mm rubbers use a non-standard thread/size - "tell me it ain't so, Shoeless Joe")?

Also, I was a little confused by your original response: which use "standard threads" Omer/Cressi/Picasso/Cressi & Picasso/everybody except Cressi & Picasso/everybody except Omer, Cressi & Picasso?