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Old 03-29-2022, 10:14 PM   #1
ninjagazz
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Fusion Rollers vs Standard Rollers

Hi Guys,

I was wondering if anyone has had any experience with fusion rollers like the one in the link below?

I don't like normal rollers as they tend to be very very muzzle heavy and I havened used one with impressive performance, but I like inverted rollers as they don't have the muzzle weight issue (much smaller muzzles) and they have less recoil/jump, they are more complex though.

The fusion looks easy to build + use and should still get good shaft speed. Perhaps enough to achieve max velocity for the spear/rubber combo?

My favourite length is 110.

https://www.youtube.com/watch?v=HuvYGMIhuio
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Old 04-09-2022, 01:46 PM   #2
spearq8
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Re: Fusion Rollers vs Standard Rollers

I have tried many variations of the system shown and tested them quite extensively in the pool. I think they are better than double action rollers but not as good as single action rollers. With normal rollers they are front heavy as some are using extremely heavy heads with ceramic bearings (very heavy). But if you have a CF pipe then front weight could be ok even with the heavier front ends.

Basically the difference is that what is called "Fusion" is an invert roller for pipe guns. In the video the system shown is actually in my opinion the best shooting ... although not the most powerful. The reason it is the best shooting is that the top bands act as "stoppers" for the wishbone and stop the wishbone before it can flip the tail of the shaft up and keep shots from shooting low. This is done at the cost of less power as the bands lose some inches of band effective band stretch. However I did experiment with higher stoppers and they seem to be able to prevent wishbone tail flip without needing the rubber stoppers ... thus gaining back the lost band stretch. Power comes from the bottom bands where you can add as many as 6 or even 8 bands !!!

I will say that these guns are extremely difficult to setup where you can get it to shoot accurately and with good power. Any tiny little change in the setup can completely change your impact point and screw up accuracy. They really feel cool to shoot if setup well and the best difference in feel to a classic gun is that it feels like you are shooting with a silenced rifle or pistol. I would not recommend it for guns longer than 85cm though. Today with even an 82cm classic 2 banded gun you can get incredible performance with incredible accuracy ... with much less complications and a much quicker loading profile. At least personally I just never enjoyed hunting with them when compared to a well setup classic gun.

By the way Ermessub has a very nice handle with a full DR trigger built in. He also has the invert roller head you saw in the fusion video as well as a classic head. Also a new almunium barrel. His handle has a lot of stuff on it that allows adding all sorts of accessories you might want in a invert roller setup. Might be a good idea to get a good CF barrel .... from Pathos for eg. ... then experiment with classic and invert and come up with an invert system and see if you like it. If you don't ... you could always switch to the classic muzzle in less than a minute.
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Old 04-14-2022, 05:58 AM   #3
Kiwizach
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Re: Fusion Rollers vs Standard Rollers

Hi guys, thanks for asking the question and thanks for your wisdom, as always, Majd.

Just a couple clarifying questions, Majd:

1) When you say you think they are better than double action rollers, but not as good as single action rollers, did you get this round the right way? Why do you prefer single action to double action rollers?

2) You said you "did experiment with higher stoppers and they seem to be able to prevent wishbone tail flip without needing the rubber stoppers ... thus gaining back the lost band stretch." Could you elaborate on this? I understand your thoughts on the wishbone causing tail flip in the shaft, but what do you mean by "higher stoppers"?

3) I have just set up one of these guns as a two stage fusion system, please see the attached, unloaded, 1st stage and 2nd stage photos. The main bottom bands, and the top bands are 16mm run at 340% stretch. The too band has a core to prevent further elongation. The secondary bands are 14mm gomma rubbers at 400% stretch. It shoots where I point it and hits the end of a single wrap pretty damn hard as well as has very low recoil. While making it I couldn't figure out in my head how adding pretension to the bottom bands would make the system work better, because the more pretension you add then the less stroke length you get for any given total band stretch. So I went with no pretension on the bottom bands. In your experiments how did pretension on the bottom bands affect performance?

Thanks

Photos are only of loading to rest tab as I was out of the water.

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Old 04-15-2022, 05:12 AM   #4
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Re: Fusion Rollers vs Standard Rollers

Fusion is just another name for an invert roller. I really don't know what part makes the invert roller "Fusion". I am guessing that it is the pipe gun version of an invert roller. An invert roller differs from a normal roller in that you pack the bands all on the bottom and you just have a cable on top. So the invert roller wheels hold a cable while a normal roller wheel the band itself is on the wheel. Problem with both systems is that there is a rotational force at the muzzle that seems to lift the tail of the shaft up as the shaft is exiting the track. This was really a big problem if you were trying to add power ... the more power you added the faster the shaft would dive and impact the target low. For a long time it seemed like I was the only person that noticed that ... maybe because you notice it more in a pool setting. Of course if you only shoot at very short distances then this is not a problem ... but if you are in clear water and you want to make longer shots ... this becomes a huge problem.

I am not sure who came up with the idea of having little bands on top and what the reason for that was. It would seem that those little bands are counter productive as it would be better to have all the power bottom side. But those little bands dramatically improve the tail lift as they allow the wishbone to release the shaft much earlier and thus avoid the tail lift. These top bands usually have rope inside them to limit the stretch. This does come at the cost of less performance of course as you are releasing the wishbone from the shaft shark fin quite a bit earlier and thus not utilizing the full track real estate. Remember that the main advantage of a roller was always that you utilize the full track real estate while on a classic speargun you can't as the bands without stretch, use up a lot of the track. But this seems to be a good compromise by giving up some power and getting back some shaft stability. However ... I have yet to see an invert roller or roller outperform a well setup classic gun in either performance or in accuracy. That doesn't mean that they are not good ... lot of people use them and love them and don't mind the extra time it takes to load and the extra things that can possibly go wrong ... but really that is a different subject. My guess why we don't see the theoretical performance advantage that physics tells us should be there over a classic setup is because of Terminal Velocity. Each shaft can only go so fast until drag forces make the velocity constant after a certain point. Adding more power on a shaft that is already at TV does not improve performance and can actually hurt performance.
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Old 04-15-2022, 03:49 PM   #5
popgun pete
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Re: Fusion Rollers vs Standard Rollers

Originally rollerguns had wishbone catchers that stopped the wishbone without lifting it, so the shaft flew from the muzzle without getting a tail lift from the wishbone. If the wishbone is hooked under a shaft tab on inside a shaft slot and the wishbone is raised it will take the shaft tail up with it. The inverted rollergun is a cable rollergun and has a band battery operating via sub pulleys on the end of the battery. Some time back there was an interesting set of photos and I reproduce them again here. The comparison shows the cable rollergun rotating on the shooter’s hand and tipping the muzzle up and knocking the shaft tail up. The set of shooting photos show the cable rollergun recoiling if you flick between them. A lot of mumbo jumbo is written about rollerguns, but the laws of physics prevail.

The white line is on the shaft axis, you can see that it changes angle as the gun shoots. The gun body angle changes are indicated by the red lines which clearly show the gun tipping up.

http://www.spearboard.com/showthread...=kraken&page=5
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Old 04-15-2022, 07:29 PM   #6
Kiwizach
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Re: Fusion Rollers vs Standard Rollers

Hi Majd,

I think you are not taking into account that the fusion set up has no pulleys to demultiply the bottom bands.

I will explain the differences as I understand them and why they have rubbers on top in a fusion set up.

A stock standard inverted roller is a gun with the rubbers pulling in the inverse/opposite direction to spear travel, achieved by putting the rubbers underneath with a direct/ 1.1 link to the spear via a cable and the rollers at the muzzle. No pulleys to dultiply the effort etc.
In these set ups the stroke length achieved is pretty much the same, if not a little worse than a traditional gun.
There are two potential solutions to this problem, they are:

Invert Fusion rollers, to increase the stroke length of a normal inverted gun described above you replace a section of the cable on top of the gun with rubbers which can be much shorter. This helps to increase the stroke length by pulling the spear closer to the muzzle of the gun, and also helps prevent tail flip as you have mentioned. Called a fusion as there are inverted aspects and traditional aspects to how the shaft is propelled.
These guns are actually very simple to use, the little bands on top make loading easier as you have something to grab onto, just load the top band, then, if you have multiple rubbers on the bottom, flip and load the bottom.
Advantages of this system are the low felt recoil and longer stroke length than a traditional set up. But like you say, not sure if this translates to more power in the real world.

Very hard to find any info or testing on fusion set ups.

Demultiplied inverted rollers, (I believe this is what most people are referring to when they say inverted roller) to make up for the short stroke length of the inverted rollers described above you introduce a pulley system to the bottom bands, this lets you get half the power over twice the distance, and now we have a stroke length that covers the entire length of the barrel. To make up for the half power we just add a bunch of bands underneath that we load one by one.

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Old 04-15-2022, 09:19 PM   #7
popgun pete
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Re: Fusion Rollers vs Standard Rollers

An inverted rollergun has the bands stay on the bottom, which is why it is “inverted”. If you have a cable drive that travels the full length of the top deck then there is no room for the bands on the gun, so the “Demultiplying system” (sub-pulleys) allows a half stroke on the bottom of the gun for the bands which translates to a full stroke on the top deck for the wishbone cable. Some guns are simple rollerguns, but mount the band anchor down the back end of the gun with the band in two parts, a thicker rear section that stays under the gun and a thinner stretch limited section that travels over the muzzle rollers and occupies the top deck when cocked, so the gun has a stretchy top cable in effect. Salvimar’s Tomahawk is a production tube gun using this principle, but it follows on from many others like Alemanni that have been discussed here before.
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Old 04-16-2022, 02:43 AM   #8
spearq8
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Re: Fusion Rollers vs Standard Rollers

Quote:
Originally Posted by Kiwizach View Post
Hi Majd,

I think you are not taking into account that the fusion set up has no pulleys to demultiply the bottom bands.

I will explain the differences as I understand them and why they have rubbers on top in a fusion set up.

A stock standard inverted roller is a gun with the rubbers pulling in the inverse/opposite direction to spear travel, achieved by putting the rubbers underneath with a direct/ 1.1 link to the spear via a cable and the rollers at the muzzle. No pulleys to dultiply the effort etc.
In these set ups the stroke length achieved is pretty much the same, if not a little worse than a traditional gun.
There are two potential solutions to this problem, they are:

Invert Fusion rollers, to increase the stroke length of a normal inverted gun described above you replace a section of the cable on top of the gun with rubbers which can be much shorter. This helps to increase the stroke length by pulling the spear closer to the muzzle of the gun, and also helps prevent tail flip as you have mentioned. Called a fusion as there are inverted aspects and traditional aspects to how the shaft is propelled.
These guns are actually very simple to use, the little bands on top make loading easier as you have something to grab onto, just load the top band, then, if you have multiple rubbers on the bottom, flip and load the bottom.
Advantages of this system are the low felt recoil and longer stroke length than a traditional set up. But like you say, not sure if this translates to more power in the real world.

Very hard to find any info or testing on fusion set ups.

Demultiplied inverted rollers, (I believe this is what most people are referring to when they say inverted roller) to make up for the short stroke length of the inverted rollers described above you introduce a pulley system to the bottom bands, this lets you get half the power over twice the distance, and now we have a stroke length that covers the entire length of the barrel. To make up for the half power we just add a bunch of bands underneath that we load one by one.

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The roller on muzzle itself is a multiplier, adding multipliers bottom side is just to pack more energy. The thing with the top band is ... does it really add any calculable velocity? I mean it is a tiny band and has a rope inside it! I have a feeling it doesn't add that much velocity. But what I can tell you that it does prevent tail lift ... and that is a major achievement. I am pretty sure that "tail lift" was not the reason those bands are used, but who cares ... if it works then all the power to it!

I will say that there might be a better solution for tail lift. Basically just have the muzzle wheel wishbone level with the CG of the shaft. You would need to elevate the wheel quite a bit higher and the stopper would also have to be higher. But this would mean that the wishbone push would be perfectly horizontal and would could stop all the way to the muzzle stopper and still be horizontal. This would negate the need of the top little bands and you could have a full usage of the track to propel the shaft.

During lockdown here I spent some time designing this exact concept. I had 2 x C4 Urukay 120's and my plan was to design a pulley system that describes the above. One gun would be an improved classic setup and the other would be an invert roller maxed out. Then I would max each out and see what does best. I would 3D print the parts I needed in metal. But sort of got caught up with other stuff so never really finished this project. I also at one point decided I didn't like the trigger and that it needed to have a custom trigger. That part of the project I finished and I do have several custom Titanium 3D printed DR trigger that work perfectly. One day I might finish that project and it definetly would be an interesting experiment as it is a perfect bed to tune and test different ideas and see what works best. The C4 Urukay has a very interesting design that allows the addition of one or even 2 rollers. It is constructed of incredibly strong full core Carbon Fiber and has SS nuts embedded that allow design of super strong chassis that can be bolted on for both muzzle wheels and for demultiplier bottom connections.



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Old 04-16-2022, 03:31 AM   #9
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Re: Fusion Rollers vs Standard Rollers

What is the point of a Double Pulley system ie 2 Wire Sheaves for 2 Lines? Is it so that less stress is placed on two different points? Doesn't it make more sense to just load up one bank? Why have Two Sheaves offset like that? Wouldn't it be best to be inline?

I always thought the Fusion System was the Inverted Roller with Short Bands on top set at a minimum stretch. Maybe it acts like a whip. Is that Band Section on the top of the gun is going to constrict faster than the rollerband it's attached to? giving it some SCHNAP!?
But, Isn't that Roller System throwing that Shaft progressively faster? So losing length of pull is not a 1:1. Who knows what those last 12" of pull do? If I understand it all correctly, that is when those bands are speeding up the most?
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Old 04-16-2022, 06:31 AM   #10
Kiwizach
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Re: Fusion Rollers vs Standard Rollers

Quote:
Originally Posted by spearq8 View Post
The roller on muzzle itself is a multiplier, adding multipliers bottom side is just to pack more energy. The thing with the top band is ... does it really add any calculable velocity? I mean it is a tiny band and has a rope inside it! I have a feeling it doesn't add that much velocity. But what I can tell you that it does prevent tail lift ... and that is a major achievement. I am pretty sure that "tail lift" was not the reason those bands are used, but who cares ... if it works then all the power to it!



I will say that there might be a better solution for tail lift. Basically just have the muzzle wheel wishbone level with the CG of the shaft. You would need to elevate the wheel quite a bit higher and the stopper would also have to be higher. But this would mean that the wishbone push would be perfectly horizontal and would could stop all the way to the muzzle stopper and still be horizontal. This would negate the need of the top little bands and you could have a full usage of the track to propel the shaft.



During lockdown here I spent some time designing this exact concept. I had 2 x C4 Urukay 120's and my plan was to design a pulley system that describes the above. One gun would be an improved classic setup and the other would be an invert roller maxed out. Then I would max each out and see what does best. I would 3D print the parts I needed in metal. But sort of got caught up with other stuff so never really finished this project. I also at one point decided I didn't like the trigger and that it needed to have a custom trigger. That part of the project I finished and I do have several custom Titanium 3D printed DR trigger that work perfectly. One day I might finish that project and it definetly would be an interesting experiment as it is a perfect bed to tune and test different ideas and see what works best. The C4 Urukay has a very interesting design that allows the addition of one or even 2 rollers. It is constructed of incredibly strong full core Carbon Fiber and has SS nuts embedded that allow design of super strong chassis that can be bolted on for both muzzle wheels and for demultiplier bottom connections.







I don't see the muzzle roller as a multiplier, all it does is allow the tension force on the cable to change direction, the force is not increasing or decreasing. Ignoring the small rubbers on top, the rubbers move 1cm forward for every 1cm that I move the wishbone back.

I guess in terms of the rubbers on top there would be different effects from different strength rubbers, I'm using 16mm American latex at 340% so while it is less powerful than the two rubbers underneath, it still packs a good punch.

In my set up, Without the top rubber, the wishbone would loose connection with the spear ~40cm from the muzzle. With the addition of the top rubber, the wishbone now looses connection with the spear 17cm from the muzzle, that's a gain of 23cm of stroke length. I hear what you are saying though, how can you tell if it is actually acting on the shaft for that extra 23cm? Maybe it isn't. But I think it probably is and here's why:
If I have both sets of rubbers connected underneath the gun and I then pull on the small top rubber it will move the bottom rubbers as well, therefore I speculate that all of the rubbers will be contracting simultaneously during the shot and pulling the shaft for the entire stroke length?


I like those drawing Majd, they look great, have you looked at the B Daniel inverted roller spear guns? If not then I highly recommend that you do. They seem to have put a lot of thought into the placement of the rubber banks to further minimize recoil and the wishbone also appears to be set up in a way that will prevent tail flip, just an amazing looking gun all round.

Great discussion so far.

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Old 04-16-2022, 06:34 AM   #11
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Re: Fusion Rollers vs Standard Rollers

Most rollerguns with elaborate band systems are just to split the reloading effort so the gun can be charged up in stages or fired with some bands not hooked up. Only so much energy can be transmitted to the shaft before it buckles under the load, so no point in adding too many bands. Fully supported shafts can be driven at the highest speeds out of hydropneumatic guns as the shaft cannot buckle in the barrel, it gets spat out so fast the shaft tail can destroy the slide rings with the gun at maximum pressure. There is no magic to such guns and they are slow to load and heavy, they just allow multiple pumping loading in the water and there is no barrel sliding piston to crash into a muzzle. Shafts don't have a limited speed, they have a limit that they can be accelerated at if unsupported on all sides depending on their stiffness, diameter and length. Band guns usually have unsupported shafts and closed track band guns still have a slot and don't have axial drive, they are usually driven off to one side. That limits how power can be transferred to the shaft.

The “Fusion” system is a variation on inverted and normal rollerguns where the cable wishbone end has a short set of bands integrally attached which in turn carry the final wishbone loop that hooks onto the shaft tab. These short bands act as stoppers when the drive cables pull them through cable guides just rearwards of the muzzle rollers as the rear bands cannot fit through the guide holes. A similar stopper system was used on the Vacondio guns where annular bump rings hit a bridge at the muzzle to stop the bands, only there they are part of the band ferrules as it is a basic rollergun and the holes in the bridge lets the bands through but not the rubber stoppers. By holding the wishbone at the muzzle and with it projecting slightly rearwards due to the anchoring action of the stoppers you can prestretch the bands in the gun whether it is a simple band or a band battery. The Fusion system gives you a couple of band lengths to grab onto as loading handles which also have some stretch. Prestretch bands are created in other inverted rollerguns by having top and bottom deck wrapping bands running on big rollers just in front of the rear handle, these bands anchored forwards and sitting in troughs moulded into the top deck that flank the shaft track. Hence the Fusion system is a variation on existing methods, but gives you something to grab onto other than a cable loop when cocking the main wishbone. Another way to look at it is a composite band gun where one band connects to two more behind it with the link now being a long cord instead of a very short one and the front band trapped on the top deck behind a catching system for the wishbone that stops that band, although here it is very short.
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Last edited by popgun pete; 04-17-2022 at 02:46 AM. Reason: more info, typo
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Old 04-17-2022, 03:06 AM   #12
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Re: Fusion Rollers vs Standard Rollers

If you look closely you will see that the illustration is actually both a single roller and double roller design in one illustration. In Fusion 360 you can eliminate items one by one. I also think it makes much more sense to have one roller and pack all the energy into the optimal shark fin with maximum track real estate possible (furthest wheel) ... but the C4 has also bolt locations back so I figured why not also try double. Also this way can possibly modify where the wishbone stops. Obviously the ideal would be to have the wishbone stop further up front ... but maybe that doesn't work well and you need to stop it earlier. Many ideas to try out and most likely something positive will be gained. I also included in the front roller a wishbone shock absorber where maybe by reducing the speed of the wishbone at the very end ... it might help release the wishbone from the shark fin in a more stable way. Many ideas and many things to try out and possibly something positive comes out. For this C4 I also wanted to eliminate the trigger as being a potential accuracy killer ... so I designed a custom C4 double roller trigger for that. That part of the project probably took way too much time but really gave me many ideas for better trigger manufacturing systems. The C4 DR trigger I have now weighs half the weight of the original trigger and has of course a much better trigger pull.

I have seen the Basil Daniel roller where he has the wheels slanted inwards ... but really have no idea how that gun shoots. For me to really find out how a gun shoots I need to put it in a pool with a static target. Test shots at different distances for accuracy and shaft drop ... and then test power by using penetration tests. I have yet to see any roller gun outperform a good classic setup in either accuracy or power at least not from 80cm guns to 135cm guns using 6.5 to 9mm shafts. That is the envelope I tested.
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Old 04-17-2022, 03:10 AM   #13
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Re: Fusion Rollers vs Standard Rollers

Quote:
Originally Posted by popgun pete View Post
Most rollerguns with elaborate band systems are just to split the reloading effort so the gun can be charged up in stages or fired with some bands not hooked up. Only so much energy can be transmitted to the shaft before it buckles under the load, so no point in adding too many bands. Fully supported shafts can be driven at the highest speeds out of hydropneumatic guns as the shaft cannot buckle in the barrel, it gets spat out so fast the shaft tail can destroy the slide rings with the gun at maximum pressure. There is no magic to such guns and they are slow to load and heavy, they just allow multiple pumping loading in the water and there is no barrel sliding piston to crash into a muzzle. Shafts don't have a limited speed, they have a limit that they can be accelerated at if unsupported on all sides depending on their stiffness, diameter and length. Band guns usually have unsupported shafts and closed track band guns still have a slot and don't have axial drive, they are usually driven off to one side. That limits how power can be transferred to the shaft.

The “Fusion” system is a variation on inverted and normal rollerguns where the cable wishbone end has a short set of bands integrally attached which in turn carry the final wishbone loop that hooks onto the shaft tab. These short bands act as stoppers when the drive cables pull them through cable guides just rearwards of the muzzle rollers as the rear bands cannot fit through the guide holes. A similar stopper system was used on the Vacondio guns where annular bump rings hit a bridge at the muzzle to stop the bands, only there they are part of the band ferrules as it is a basic rollergun and the holes in the bridge lets the bands through but not the rubber stoppers. By holding the wishbone at the muzzle and with it projecting slightly rearwards due to the anchoring action of the stoppers you can prestretch the bands in the gun whether it is a simple band or a band battery. The Fusion system gives you a couple of band lengths to grab onto as loading handles which also have some stretch. Prestretch bands are created in other inverted rollerguns by having top and bottom deck wrapping bands running on big rollers just in front of the rear handle, these bands anchored forwards and sitting in troughs moulded into the top deck that flank the shaft track. Hence the Fusion system is a variation on existing methods, but gives you something to grab onto other than a cable loop when cocking the main wishbone. Another way to look at it is a composite band gun where one band connects to two more behind it with the link now being a long cord instead of a very short one and the front band trapped on the top deck behind a catching system for the wishbone that stops that band, although here it is very short.

Yes absolutely! People don't realize that you can easily saturate energy into a shaft where adding more energy starts to backfire on you. If the shaft exits the track ustable ... it will quickly dissipate energy and velocity will quickly fizzle out. I see this over and over again.
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Old 04-17-2022, 06:05 AM   #14
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Re: Fusion Rollers vs Standard Rollers

Originally simple rollerguns loaded the wishbone in one pull and if you wanted two bites at the cherry then you could draw the rear band anchor back another notch which meant that when you fired the gun you would have prestretch left in the bands. If you wanted more grunt without stepping up the band diameters then you added another roller axle similar to the first one, but this made two stage loading more difficult as you had to move two rear band anchors. But the loading effort was just duplicated without upping the maximum draw required of the operator

The inverted demultiplied rollergun with sub-pulleys meant that the band battery had to be doubled up anyway as tension in the cable wishbone is always halved by the sub-pulley system, the other half is borne by the cable anchor fixed at the muzzle. But this opened up the way for piggy back bands anchored on the sub-pulleys which could be loaded separately, so more energy could be stored in the gun by loading extra piggy back bands which, provided the single cable can take the strain, is more effective than crowding the muzzle with extra roller axles. The muzzle rollers are small diameter because they don't have to curve band rubber without scrunching it, instead they just route thin cables. If you put knots in the cables forwards of the wishbone then you can stop the drive without lifting the wishbone up by catching the knots in a nip between the rollers and a restricting element, that is what Seal did on his inverted rollergun, but you need to load on the rearmost shaft tab as you don’t want to risk snagging the wishbone.

The composite band rollerguns allow piggy back loading because they have a Y connection in the bands, only one of the rear band pair has to be anchored to load the gun, the others can be loaded later. These guns are not demultiplied, but the thinner front band that wraps the muzzle rollers has to be stretched limited otherwise the piggy back bands will stretch the guts out of the front bands when everything is loaded up. The Fusion guns don’t run rubber over the muzzle rollers, but their front bands are restricted to the top deck in their composite band layout. If the composite bands at the rear are replaced by a sub-pulley band battery then you need to remember the stroke on the top deck to the stoppers is shorter by the length of the stopper bands when contracted as the wishbone does not traverse the full length of the top deck.
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Old 04-17-2022, 04:52 PM   #15
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Re: Fusion Rollers vs Standard Rollers

Rollerguns need to be strongly built as even on a single band rollergun tension top and bottom in the band doubles the load on the muzzle via the roller axle, so it is like a two band gun in a sense. Composite band rollerguns are the same as tensioned band rubber occurs on both decks (top and bottom). Inverted rollerguns with sub-pulleys have to be even stronger as while they only shoot with half the tension of the band battery (that is why they are "demultiplied", the cable tension to the spear is halved) they have to endure the full loading of the band battery with the gun being squeezed by the pull from the locked in shaft tail at the rear on top and the band anchor points on the bottom against the opposing pull from the roller axle and the cable anchor at the muzzle. A saving grace of these rollergun constructions is tension occurs both top and bottom with the stock unlikely to banana in the vertical plane.
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