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Rob Allen guns????
- Thread starterheebes
- Start date
Thread Status: Hello
, There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
It can take a long time to get an up-to-date response or contact with relevant users.
In europe you can buy Rob Allen guns from:
European site: www.roballeneurope.com
Portuguese site:www.roballen.submerso.net
both know very well the guns and have use it for years. they´re also very friendly and can give very usefull tips advices and stories
Fernando
European site: www.roballeneurope.com
Portuguese site:www.roballen.submerso.net
both know very well the guns and have use it for years. they´re also very friendly and can give very usefull tips advices and stories
Fernando
RB shafts are $40 ??? :vangry I bought a 120 cm Shaft for $20 something dollars last year. Perhaps they gave me a special deal. Perhaps the dollar Rand exchange rate changed.
If I were the Rob Allen I would either give the guns away at cost and mark up the shafts or I would sell guns at a mark up and give away the shafts.
If I were the Rob Allen I would either give the guns away at cost and mark up the shafts or I would sell guns at a mark up and give away the shafts.
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Iyadiver said:
Probably because some contributors reckon the rail makes no noticeable difference to accuracy in practice & that it is mainly marketing hype (although they generally acknowledge it stops the wobble thing). That might also explain why Omer is offering a cheap stick-on rail that, I think, can be used on pretty much any euro-gun. Its a clever idea:
- if you don't care, you can buy their euro-gun,
- if you do care -- you can buy their euro-gun with a rail stuck on
- if you are unsure -- you can buy their euro-gun and "upgrade" with a rail later, if you feel the need/desire
- if you have a different euro-gun you can buy their rail
The one thing it suggests to me is that they do not see rails as being essential to producing good spear guns at reasonable prices. They are looking to solve the marketing issue, a perception issue rather than seeing any actual weakness in their existing designs that warrant changing.
It seems like rails are pretty normal on bigger guns (esp. non-euro guns) -- Rob Allen rails guns are Euro-style but they are made in Africa -- have you seen the size of the fish they get out there. Oh mama!
[I have no affiliation with anybody]
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Re: hi IYA
I thought most (/many) RA's can be used with 2 rubbers (even though fitted with just one from the factory)? So why not just slap another rubber on there an have done with it?!
BTW Did the spear line limit the range or just power?
ivan said:
I thought most (/many) RA's can be used with 2 rubbers (even though fitted with just one from the factory)? So why not just slap another rubber on there an have done with it?!
BTW Did the spear line limit the range or just power?
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Re: RA dealer
For Europe try:
http://www.RobAllenEurope.com/ are the currently the official RA european dealer/distributor. The Rob Allen kit is first class
. Lots of cool links from this site too.
Try http://www.spearo.co.uk too, Dave is also knowlegable & helpful -- and it looks like he is on some of these threads. Dig around this site, he has a lot of different spear guns, including some exotics (C4, Carbon fibre Rob Allens, cool looking Seatecs), although it is not obvious at first. I like his no non-sense product selection and advice.
Both have problematic on-line shopping carts ("under development" ) -- so you might find it easier/essential to email orders in.
I don't think Neil at http://www.apnea.co.uk in Jersey carries RA currently(?) but he has a very large selection & apparently more not listed on-line. Has always given me great advice re. gear selection.
http://www.mikesdiving.co.uk/ has a limited selection but reasonable prices.
http://www.portlandoceaneering.co.uk/ have a "bricks & mortar" store on Portland -- the place for good local advice apparently.
[I think there might be a portugeuse/french/finnish RA dealers/sites too(?), if you speak their respective languages (& can tolerate their VAT rates!). Also, RA home site in South Africa (.za?) is always worth a look & the Oz/NZ dealers]
For US or just choosing the right length, try Sumora...especially this page:
http://www.sumora.com/Railgunchart.php
For a quick overview of popular SA railguns, this Oz site is must see: http://www.spearfishing.com.au/fram...earfishing.com.au/shop.php?group=southafrican
shaneshac said:
For Europe try:
http://www.RobAllenEurope.com/ are the currently the official RA european dealer/distributor. The Rob Allen kit is first class
. Lots of cool links from this site too.Try http://www.spearo.co.uk too, Dave is also knowlegable & helpful -- and it looks like he is on some of these threads. Dig around this site, he has a lot of different spear guns, including some exotics (C4, Carbon fibre Rob Allens, cool looking Seatecs), although it is not obvious at first. I like his no non-sense product selection and advice.
Both have problematic on-line shopping carts ("under development" ) -- so you might find it easier/essential to email orders in.
I don't think Neil at http://www.apnea.co.uk in Jersey carries RA currently(?) but he has a very large selection & apparently more not listed on-line. Has always given me great advice re. gear selection.
http://www.mikesdiving.co.uk/ has a limited selection but reasonable prices.
http://www.portlandoceaneering.co.uk/ have a "bricks & mortar" store on Portland -- the place for good local advice apparently.
[I think there might be a portugeuse/french/finnish RA dealers/sites too(?), if you speak their respective languages (& can tolerate their VAT rates!). Also, RA home site in South Africa (.za?) is always worth a look & the Oz/NZ dealers]
For US or just choosing the right length, try Sumora...especially this page:
http://www.sumora.com/Railgunchart.php
For a quick overview of popular SA railguns, this Oz site is must see: http://www.spearfishing.com.au/fram...earfishing.com.au/shop.php?group=southafrican
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freediver7 said:
I did that a few times too, there was only slight deformation -- I touched up the tip with a few strokes of a small mill bastard file (I figure that, like an ice axe, it should probably only be cold worked) & it is like new again now.
I recently bought several pieces of RA gear (railgun, float, line, stringer, net bag,...) and it is all good, well designed, solid, quality stuff. They catch huge fish in SA -- so it well tested. (Like German cars being thrashed on the the autobahn -- the end result tends to be a more robust product).
Hi Mr.X,
You touched on a bunch of interesting topics that you seem clear on but if you don’t mind I wanted to clarify some of the things you mention since these are fundamental principles in spearguns that a lot of people don't understand quite easily. It really caught my attention and it’s a basis for understanding what the purpose and advantages and disadvantages of these designs are.
Starting with the general idea that of the generally accepted view that it stops the "wobbling" thing.
It is important to realize that a rail, or integrated, or stick on shaft guide is not a universal application for spearguns. It plays an important part in reducing the dispersion of energy through shaft-whip (shaft wobble) in spearguns where the bands are not perfectly aligned with the shaft, or in spearguns that may be over powered. If the bands in an open muzzle band gun for example with offset bands are pulling the shaft down onto the barrel without the support of a shaft guide the shaft will arch down! It will touch the barrel and when you shoot it, it will be going out like a banana as it tries to spring back into shape! You don’t have this problem when the bands pull the shaft STRAIT out of the gun.
In spearguns with a circular loop through band in an open muzzle style speargun for example, the bands are declining in comparison to the flat linear axis of the shaft, e therefore the shaft undergoes an axial force from the bands as well as a transversal (diagonal) pull of the bands pulling the shaft down to the shaft guide. All surfaces being equal, however much greater the transversal force of the bands pulling down the shaft into the track guide, the greater the amount of energy dissipated in the non linear direction of the shaft.
In spearguns with a pair of bands mounted to a traditional in line closed muzzle (or similar) a little bit of the transversal factor could be present, depending on how well that particular speargun parallel alignement between bands and shaft is. For whichever gun has the perfect linear alignment between shaft and bands the transversal (again the offset diagonal pull of the bands) factor is no longer an issue: in this case however, the perfect alignment of the bands renders the addition of a rail/shaft guide/glue or rail COMPLETELY USELESS. The reason is obviously that now that the alignment of the shaft and bands is perfect the shaft is pushed towards its target along its own longitudonal axis.
For some guns, therefore, the shaft guide or rail can be completely superfluous, considering that the energy potentially returned to the shaft from the bands will be greater in that it won't be wasted on a transversal force pull.
Rails or integrated shaft guides or stick on raild are no recent innovation to spearguns. As far as European guns go OMER was the FIRST speargun to integrate an integrated shaft guide design into the barrel. The founder of Omer, Valerio Grassi, had them on his first production models in the late 70's and early 80's:
In fact by looking at the link you might also see some of the early muzzle designs which look a lot like the South African rail muzzles presently on the market. In these earlier designs the perfect alignment issue between bands and shaft still wasn't produced by injection molded screw in muzzles and so for this the system they adopted the older muzzles which brought the bands in line and it worked well. The shaft or rail guides were done away with in later designs because the alignment issue was resolved and with only a single band used no support or rail was longer needed.
As you mentioned earlier in your post, the stick on rails are intended for modifications or designs that strey from the ones where this issue of alignment has not yet been resolved: open muzzle spear guns, or the addition of a second loop band to a closed muzzle gun for example. When you change or modify a speargun and the alignment of the bands a rail could come in handy to compensate for the error.
But still, the most energy efficient design that makes the most out of the power of any set of speargun bands is a linear pull design. Once the owner of the company C4 (a mechanical engineer) who produces carbon fins and spearguns told me that according to him one set of screw in bands in his gun was more powerful than two sets of non linear pull diagonal bands in an open muzzle. Whether this was true or not I'm not sure honestly however all the above is true because its just simple physics. What goes up must come down…
You touched on a bunch of interesting topics that you seem clear on but if you don’t mind I wanted to clarify some of the things you mention since these are fundamental principles in spearguns that a lot of people don't understand quite easily. It really caught my attention and it’s a basis for understanding what the purpose and advantages and disadvantages of these designs are.
Starting with the general idea that of the generally accepted view that it stops the "wobbling" thing.
It is important to realize that a rail, or integrated, or stick on shaft guide is not a universal application for spearguns. It plays an important part in reducing the dispersion of energy through shaft-whip (shaft wobble) in spearguns where the bands are not perfectly aligned with the shaft, or in spearguns that may be over powered. If the bands in an open muzzle band gun for example with offset bands are pulling the shaft down onto the barrel without the support of a shaft guide the shaft will arch down! It will touch the barrel and when you shoot it, it will be going out like a banana as it tries to spring back into shape! You don’t have this problem when the bands pull the shaft STRAIT out of the gun.
In spearguns with a circular loop through band in an open muzzle style speargun for example, the bands are declining in comparison to the flat linear axis of the shaft, e therefore the shaft undergoes an axial force from the bands as well as a transversal (diagonal) pull of the bands pulling the shaft down to the shaft guide. All surfaces being equal, however much greater the transversal force of the bands pulling down the shaft into the track guide, the greater the amount of energy dissipated in the non linear direction of the shaft.
In spearguns with a pair of bands mounted to a traditional in line closed muzzle (or similar) a little bit of the transversal factor could be present, depending on how well that particular speargun parallel alignement between bands and shaft is. For whichever gun has the perfect linear alignment between shaft and bands the transversal (again the offset diagonal pull of the bands) factor is no longer an issue: in this case however, the perfect alignment of the bands renders the addition of a rail/shaft guide/glue or rail COMPLETELY USELESS. The reason is obviously that now that the alignment of the shaft and bands is perfect the shaft is pushed towards its target along its own longitudonal axis.
For some guns, therefore, the shaft guide or rail can be completely superfluous, considering that the energy potentially returned to the shaft from the bands will be greater in that it won't be wasted on a transversal force pull.
Rails or integrated shaft guides or stick on raild are no recent innovation to spearguns. As far as European guns go OMER was the FIRST speargun to integrate an integrated shaft guide design into the barrel. The founder of Omer, Valerio Grassi, had them on his first production models in the late 70's and early 80's:
In fact by looking at the link you might also see some of the early muzzle designs which look a lot like the South African rail muzzles presently on the market. In these earlier designs the perfect alignment issue between bands and shaft still wasn't produced by injection molded screw in muzzles and so for this the system they adopted the older muzzles which brought the bands in line and it worked well. The shaft or rail guides were done away with in later designs because the alignment issue was resolved and with only a single band used no support or rail was longer needed.
As you mentioned earlier in your post, the stick on rails are intended for modifications or designs that strey from the ones where this issue of alignment has not yet been resolved: open muzzle spear guns, or the addition of a second loop band to a closed muzzle gun for example. When you change or modify a speargun and the alignment of the bands a rail could come in handy to compensate for the error.
But still, the most energy efficient design that makes the most out of the power of any set of speargun bands is a linear pull design. Once the owner of the company C4 (a mechanical engineer) who produces carbon fins and spearguns told me that according to him one set of screw in bands in his gun was more powerful than two sets of non linear pull diagonal bands in an open muzzle. Whether this was true or not I'm not sure honestly however all the above is true because its just simple physics. What goes up must come down…
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Another thing or two that I forgot in my last post. I would like people to understand that I am in no way trying to put down Rob Allen or rail guns or whatever, I can see many people are happy with their guns and like them very much and the importer here of RA in the USA and my company even have a good working relationship. Variety, selection. and competition is good in the market place for you!
I am merely discussing and clearing up the misunderstandings of what particular advantages and disadvantages there are to each design. The divers and the users can determine for themselves what is better for them.
Anyhow, you probably are wondering what are all the implications of all that stuff I talked about above in practical terms???
Why would most European guns have shied away from the earlier simpler designs like the ones in the "Omer Memorabilia" link in favor of screw in band designs that required more expensive injection molds and screw in bands?
Simply, single band guns become the most versatile and best all around design for European divers where the European gun comes from in general... because it makes the most out of that one band with the most efficient pull/power design. Most European gun sold in Europe have always been 110cm or less where the benefits of a single band outweighed the advantages of more bands and more hassle. Instead of looping the band around the front of the muzzle where it eventually rots it made more sense to cut it in half and screw it into the front where it would pull evenly. Simplicity is a virtue and a 20mm band with a 6.5mm or 7mm shaft is, in my opinion, a better tradeoff than two thinner bands looped around the front of the gun in a clunky muzzle.
When it comes to blue water hunting or using 120cm or longer guns in open water like they do in South Africa and in Australia much of the time it may not be the best solution, an open muzzle gun with a shaft guide and more than one band and a thicker shaft is better a lot of the times.
It's simply a matter of conditions and prey and the divers preferences.
Mark
I am merely discussing and clearing up the misunderstandings of what particular advantages and disadvantages there are to each design. The divers and the users can determine for themselves what is better for them.
Anyhow, you probably are wondering what are all the implications of all that stuff I talked about above in practical terms???
Why would most European guns have shied away from the earlier simpler designs like the ones in the "Omer Memorabilia" link in favor of screw in band designs that required more expensive injection molds and screw in bands?
Simply, single band guns become the most versatile and best all around design for European divers where the European gun comes from in general... because it makes the most out of that one band with the most efficient pull/power design. Most European gun sold in Europe have always been 110cm or less where the benefits of a single band outweighed the advantages of more bands and more hassle. Instead of looping the band around the front of the muzzle where it eventually rots it made more sense to cut it in half and screw it into the front where it would pull evenly. Simplicity is a virtue and a 20mm band with a 6.5mm or 7mm shaft is, in my opinion, a better tradeoff than two thinner bands looped around the front of the gun in a clunky muzzle.
When it comes to blue water hunting or using 120cm or longer guns in open water like they do in South Africa and in Australia much of the time it may not be the best solution, an open muzzle gun with a shaft guide and more than one band and a thicker shaft is better a lot of the times.
It's simply a matter of conditions and prey and the divers preferences.
Mark
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The fact that bands with screw on ends are not easy for the do it yourselsf guy to make at home therefore forcing him to buy more expensive usually genuine bands increasing the manufacturers after sales profit wouldn't have anything to do with the Euro manufacturers likeing this system would it?
By the way, in the RA the band is also linear and the overall band lenght that is making the pull is bigger... the rails make sense for bigger guns (in my 1.2m RA it makes sense) but, as i think that Mark said/implied for smaler guns it's not a need... For me, if you like your gun and your a sucessfull hunter with it - it is the best gun in the world (for you, until you get used to another one)
best dives
Fernando
best dives
Fernando
poacher said:
Oh-ooh, the conspiracy theory!!
Good point to consider, but consider this:When you go service your car after the warranty runs out, you're not required to go to a dealer for an expensive oil change and a tire rotation are you? If you're handy enough or have a friend who's a local mechanic you can always take it to him and save a chunk of change.
I can't tell you how many times, and I’ve been fiddling with this stuff for years and it still happens to me, I have broken the bands I've tied myself at the knot when it slips or the soft wishbone has broken. I can count on ONE HAND how many times (of thousands and thousands sold) a factory band installed band has broken or the rubber has slipped. The metal wishbones, as much as they can hurt a person whose not used to using them, don’t break at a fraction of the rate of a soft wishbone.
You see it’s all a matter of priorities, you have a guy who spends all day on the internet learning about spearguns and do it yourself applications because that’s part of his fun and he has a lot of free time, then you have a guy who’s busy with his career, his family obligations etc etc like most people and on the weekend’s he just wants to get in the water and buy something that’s ready to go without experimenting or worrying about whether it’s going to hold up.
To the later, a $25 pair of bands he might replace once a year isn’t an issue. These PURE LATEX bands are pressure tested in Kg’s by a machine that not all speargun manufacturers posess for batch consistency, cut in various sizes to fit on each gun, and the machine installs the little ball inside and stretches the rubber over the threads and this puts less wear and tear on the rubber. So they cost more but no one says you have to buy them. Or if you’re a die hard do it yourselfer you buy the little threaded adapters that screw into the couplings so you can still tie them yourself.
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marginatus said:
I couldn't agree with you more. When I dive and shoot fish in the blue water I don’t use a single band 130cm Excalibur although there are plenty of people without a big budget for a super speargun that do who are happy. I take my 110 with a reel, the stick on rail, and a circular band and my bigger two band 130cm Master America, just like other’s who might use their long RA’s or Riffe’s of whatever for that purpose. But those don’t really work so well for diving in 30ft of water with lots of current and poor vis so most divers I know use what’s more appropriate like smaller single band guns. There is never going to be one design rail/open muzzle/clozed muzzle/heavy/light gun that will always be better for every situation and consumers contemplating another gun purchase need to be able to discern those differences.
Point taken re. rails being non-essential for European size guns. Even Rob Allen is selling a non-rail model now, the Scorpia, at a slightly lower price than their railguns (just as Omer are offering stick on rails for theirs! ). I do like Rob Allen stuff, and the way they manage to cover all the bases with a remarkably small, easy to understand range of simple, well designed, robust workhorse products -- that seem a bit tougher, more powerful and a bit more versatile than the crowd. :ko
One benefit of the RA rails, often overlooked, is that being part of the tube they add rigidity & strength (& weight & cost) -- but again this is likely to be of more concern for long and/or heavily powered applications. I don't think the Rabitechs provide this (I believe they use a polymer rail) -- that said plenty of people rate them highly (inc. Miles - respect).
Omers, RA, Rabitechs, Seatec & Riffe owners all seem to love their guns, I am sure they all offer some great products. Choice is often dictated by local availability (store/on-line), price, value and the spearos you meet. I would love to take a look at the Omers and Rabitech products but never get to stores, let alone dive stores, these days. Where are their UK dealers/distributers?
BTW 90cm barrel still seems very long to me. Anybody tried equipping a 90cm eurogun/railgun with double 16mm or short 20mm rubber?
). I do like Rob Allen stuff, and the way they manage to cover all the bases with a remarkably small, easy to understand range of simple, well designed, robust workhorse products -- that seem a bit tougher, more powerful and a bit more versatile than the crowd. :ko One benefit of the RA rails, often overlooked, is that being part of the tube they add rigidity & strength (& weight & cost) -- but again this is likely to be of more concern for long and/or heavily powered applications. I don't think the Rabitechs provide this (I believe they use a polymer rail) -- that said plenty of people rate them highly (inc. Miles - respect).
Omers, RA, Rabitechs, Seatec & Riffe owners all seem to love their guns, I am sure they all offer some great products. Choice is often dictated by local availability (store/on-line), price, value and the spearos you meet. I would love to take a look at the Omers and Rabitech products but never get to stores, let alone dive stores, these days. Where are their UK dealers/distributers?
BTW 90cm barrel still seems very long to me. Anybody tried equipping a 90cm eurogun/railgun with double 16mm or short 20mm rubber?
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