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General control line discussion => Open Forum => Topic started by: Matt Curtis on December 24, 2024, 11:38:40 PM
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which is better and why? I would like to try spectra.
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So far I haven't seen any Spectra being used in world champs, European champs or in world cups, so this makes me think that Spectra is for fun-flying and steel is for more serious use. L
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I have been playing with Spectra lines for a couple of years now on my sport flying airplanes to learn the ropes, so to speak. Everything that you need to know is in the thread called "Adventures In Spectra" that I think Dennis Adamisin started. I like the durability of the lines, and I find that they help out the most in the overhead and vertical maneuvers. I forget the exact numbers, but I weighed a set of steel lines for my Rehab Ringmaster and compared that to a set of Spectra lines using 30 pound test, and it was something in the order of 2 ounces lighter. I pulled all of the tip weight out of that airplane eventually. They do not kink or get curly on you unexpectedly. I still pat attention to them as if they were steel, inspect them every session and don't step on them, and clean them frequently. I do not feel any stretching in either that I read some guys talk about. I think the model needs to be in pretty good trim first, and then fine tuned again once you switch. Since they are much lighter, they tend to blow around pretty easy when laying on the ground so I usually pull a bit of tension on them and put something on the handle if I think I need to. I have both a Bass Pro and a Cabella's shop near me and I buy my lines there to make sure i am getting Spectra. Again, check out the "Adventures In Spectra for just about everything you might need to know.
Type and you later and MERRY CHRISTMAS!!
Dan McEntee
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So far I haven't seen any Spectra being used in world champs, European champs or in world cups, so this makes me think that Spectra is for fun-flying and steel is for more serious use. L
At Muncie, Len Bourel on the Canadian team was using Spectra.
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Hello
I was testing out a Sig Magnum with ST60 a week ago and first used the steel lines the model came with, when I brought it.
Then swapped to my own Spectra lines of the same length and got a huge improvement in flying.
Mainly better overhead tension but also better turns with less inertia in squares.
Do your research to select the best options and try them .
Regards Gerald
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So far I haven't seen any Spectra being used in world champs, European champs or in world cups, so this makes me think that Spectra is for fun-flying and steel is for more serious use. L
Lauri, I don't know you from Adam.. And you are probably a far better flyer than I am, but your conclusion is not supported by your premises.
Just because you haven't seen them used, does not make them "for sport flying" vs "More serious use".
That attitude itself indicates a measure of presuppositional arrogance not grounded in fact, and that is exactly the kind of thinking that is killing control line and stunt.
Control line, Stunt, is far too important to be treated so sanctimoniously.
So please re-think your comment and provide some useful feedback.
Dan's and Gerald's comments are far more useful, and at some point, when you "big boys" have someone in your echelon who registers a few wins with them, all of a sudden, there will be a switch, and "serious flyers only use Spectra lines, those old fashioned steel lines are for less serious and less important sport flyers."
Mark
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So far I haven't seen any Spectra being used in world champs, European champs or in world cups, so this makes me think that Spectra is for fun-flying and steel is for more serious use. L
I suspect a lot of that is familiarity, the 1,000 foot rolls of steel lines still in the shop and the relatively short break-in period of steel. IMHO Spectra is better, mainly for the reasons Gerald stated but they take getting used to. If a world class flier were to give Spectra a try, I am pretty sure he/she wouldn't like them. They are different and the difference makes them not feel right at first. All of the things you do change and that can be quite annoying and that masks their superiority. Another reason is the slightly longer break-in period for Spectra. Even if you stretch the living daylights out of them, they still feel a little softer than steel at first.
My guess you will see them being used at the top of the mountain when the fliers a few ridges down switch and move up. They can afford the hundreds of flights it takes to start noticing the improvement. IMHO you simply cannot maintain the muscle memory for both at the same time.
Ken
Mark - you nailed it
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Ken,
Merry Christmas, could you please elaborate on the changes you experienced between the two? Once the Spectra lines are stable and the ship tip weight is reset and possibly the leadout location adjusted for less drag (with Spectra lines I fine you can go the smaller diameter for the same strength e.i. Finns 40G line) what changes? Are the controls faster or slower, is it just that the ship carries more speed through the maneuvers with the less draggy lines? How does this compare to solid steel lines?
Best, DennisT
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This seems like a question that could be answered scientifically with numbers.
Assume a stunt plane that weighs 50 ounces, flys on two 65' lines, and must pass a 40-pound pull test.
Then for the two types of lines, what is the mass of lines, frontal area, and cost?
The numbers will answer the question.
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I have been flying CL for about 4 years and really a sport flyer but have competed in beginner stunt and am working away at the full pattern practice. I have pretty much been using Spectra exclusively but have also used braided SS depending on the particular model. Spectra lines are easy to make up and cost me about $5 per set of lines. I have been using 65# test for 25 size (32 oz) models, and 80# test for 40-46 (60 oz) size models.
IMO some of the experts only use SS because it is what they are 'used to' and their models are specifically trimmed for the SS lines they use. If Spectra is used, some model re-trim will most likely be necessary.
Some say Spectra lines stretch too much. That is the only real negative comment I have heard so far from more experienced pilots. But don't kid yourself. SS lines also stretch under load. I was curious and did a simple stretch test comparison a few years go. I compared 60' long 015 SS lines to 65# test Spectra. I pulled each of the lines at 10 pounds (probably twice the actual load in level flight for a typical model). The 015 SS lines stretched about 1/2". The Spectra lines just under 1". So, more stretch, absolutely. But less than a 1/2" delta over 60' is negligible at my experience level.
There are always pros and cons but the only real way to see is for a pilot to try out Spectra for their own information if they are interested.
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My Spectra Experiences and test results:
• Spectra lines stretch much more than steel cable, even after the break in “Pre-Stretch”.
• Spectra lines tied with best practices from the Mike Stinson You Tube video will fail at the knot at approximately 50% of their rated capability. The manufacturers have pull test equipment to take the stress riser at the knots out of the picture.
Spectra lines are my preferred lines on light weight models. The heaviest model I fly w/ Spectra is a 41 oz classic model with an Aero Tiger 36.
Several of my larger planes (up to 68 oz. Predator) have been flown on Spectra but I prefer steel cable for the heavier models because the Spectra stretch hinders the corners IMHO.
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• Spectra lines tied with best practices from the Mike Stinson You Tube video will fail at the knot at approximately 50% of their rated capability.
That has not been my experience. I also was curious about the manuf rated load. As a test I made up a short length single line using 'new' 65# test PowerPro Spectra, using the double loop modified surgeons knot per the video. I slowly loaded the line in small increments. I went all the way up to 60 pounds and no failure of the line or knot occurred. Again, this test was on a newly made-up line. Can't speak to the failure point on lines that have seen a lot of use.
I have only used the PowerPro brand. I can't speak to other brands.
In reality, even a heavy 60+ oz model will have a level flight pull of say 10-15 lbs. That is only 5-7.5 lbs per line. And a 40 lb pull test is only 20 lb per line.
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Why use spectra? Because I can walk across the street to my local Canadian Tire and buy them.
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Ken,
Merry Christmas, could you please elaborate on the changes you experienced between the two? Once the Spectra lines are stable and the ship tip weight is reset and possibly the leadout location adjusted for less drag (with Spectra lines I fine you can go the smaller diameter for the same strength e.i. Finns 40G line) what changes? Are the controls faster or slower, is it just that the ship carries more speed through the maneuvers with the less draggy lines? How does this compare to solid steel lines?
Best, DennisT
These are just my observations and not in any particular order of importance and not repeating all of the benefits already stated. First, I do not rely on outside references except for the RWO. This is due to a "lazy" eye that does not refocus quickly. My focus is 100% on the plane. Even with my focal length pretty much at 70' I could not see steel lines easily so I pretty much ignored them. The Yellow Spectra really opened my eyes (literally) to what the lines were doing. Whip in corners, uneven tension from over controlling, sag, etc. This let me make corrective trim and style changes that really improved my flying. I started feeling the plane better, especially after I learned to really stretch the lines. They appear to have less wind resistance and slide over each other better. This led to me changing from a cable handle to a hardpoint which I abandoned when using steel lines. With Spectra it felt like there were no lines and my fingers were moving the ballcrank. Again a personal observation.
Now here is one thing that may or may not be spectra. I am a bit on a innovator so I try things. I also do not have a huge fleet of planes to fly. Since the untimely demise of my Endgame III with the canard I am down to one and it has spades. BOTH of these contribute to lower handle force required to move the controls and combined with the lower weight of the lines I am able to control the plane better in low tension conditions like overheads, much better. Both planes have been flown without the canard or spades, so I know that the improvement is partly the spectra. I do think that Spectra, in the smaller sizes does have a bit more stretch than steel but I have no scientific evidence. I can feel the difference between Regular 80lb Power Pro and 100lb Maxcurato. Same weight, less stretch. Sort of like the tradeoff between .015 and .018 steel. It is probably that softer feel combined with the faster hardpoint that lets all of the other benefits Gerald pointed out shine. I am starting to suspect that the softer feel is more perception than actual stretch. My perception is that they both stretch about the same. You expect spectra to stretch more so you feel it whether it is there or not. It is like anything else in the sport, it takes time to learn the finer points and spectra is no different. You have to stretch the living *crap* out of them before you use them. First timers usually underestimate this.
I know a lot of fliers are skeptical of it's strength. Fishing line? I have a digital scale I use to stretch my lines. On my 65oz and above I use Power Pro Maxcurato 100lb. I stretch it as a pair for 5min with my scale pegged at 50lbs, it's highest reading. If any plane pulled 50lbs it would probably be unflyable. I suspect that 80lb is plenty for anything up to 70oz but I am still a bit reluctant to try.
How far will it go? The pull test is 10x weight. 43lbs for a 70oz plane that will pull at most 14lbs in flight. Would Spectra 50lb pass? My guess is that it would but most, included me would be scared to try it. Sort of makes you wonder what life would have been like "in the day" if our .35 monsters could be flown on 30lb fishing line.
Sorry, a bit long winded n1 - Ken
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I have never used Spectra lines..
What sort of knot do you use to secure them? Clinch/Improved Clinch? Palomar?
Do you secure them directly to the clips (I use scissor clips, btw)?
I'm assuming Brodak's would be a source, but I'm guessing Bass Pro Shops might also work?
Thoughts?
Mark
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A little bit of "stretch" is a good thing compared with breaking all at once. As long as a model is flying on BOTH lines the stretch will not effect controls.
In a near-death incident on 7-strand lines, the middle strand stretches while the other six just wrap tighter and absorb the jolt. This is a valuable safety factor compared to solid steel or any other single strand line.
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A little bit of "stretch" is a good thing compared with breaking all at once. As long as a model is flying on BOTH lines the stretch will not effect controls.
In a near-death incident on 7-strand lines, the middle strand stretches while the other six just wrap tighter and absorb the jolt. This is a valuable safety factor compared to solid steel or any other single strand line.
No, you are confusing the breaking strenght and elognation before break. What we want is *the less flex possible*.
In general you should look for lines without the center strand, they are better in that respect.
If we look at the physical properties, it’s quite clear that Spectra is not the best material for our use.
Of course the end result is always a compromise, more you prefer the ideal physical properties, the more you have to be careful with the lines, but at least I personally want to lean towards the physical performance.L
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I have never used Spectra lines..
What sort of knot do you use to secure them? Clinch/Improved Clinch? Palomar?
Do you secure them directly to the clips (I use scissor clips, btw)?
I'm assuming Brodak's would be a source, but I'm guessing Bass Pro Shops might also work?
Thoughts?
Mark
The recommended knot is a modified surgeon's knot with a double loop. There is a good video on the 'Adventures in Spectra' post on how to tie the knots.
I have only used the PowerPro brand without issue. There are other brands on the market, but not sure if all brands are the same strength-wise.
I secure mine directly to the clips as shown in the video. (I also use scissor clips)
Brodak does not sell Spectra. Some fishing and tackle shops carry Spectra, but not the 65- and 80-pound strength I use. I have been finding these on eBay. I buy like a 300 yd roll. I can make up a set of 60' lines for around $5.
I also use Spectra for my stooge line since there is little if any stretch.
A 'high visibility' yellow color is also recommended. It is very difficult to see the other Spectra colors when the lines are on the ground, especially moss green color (great for fishing, bad for CL).
The AMA also has the following guideline:
Model weight oz Rated Spectra lbs
24 20
40 40
64 60
75 100
These would be minimum strengths vs model size.
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Ken Bauer just wrote an article about towlines (nowadays mostly Spectra or similar) in the latest FF Symposium. He tested several knots, not much difference between them when prepared correctly.
I use Uni-Knot, it’s good enough for me.
The only ending that stands well above others is the spline, it’s about double strenght compared to any knot.
Spline is not reallt a knot, you just guide the end of line inside itself. L
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The better question why use stee lines now?
I did a presentation for our club. I summarized the data on weight, stretch, and other things. All this is from threads and data sheets. There were no feelings or subjective decisions.
I won't buy any more buy stranded lines.
The only downside is when steel lines need to be replaced, it is clear. The spectra lines don't kink or break stands. I can't tell with the spectra lines, and I am careful to not have them abrade.
No, they don't stretch any more than steel lines, and they are smaller in diameter for the same breaking strength. They are a little more draggy and once you know how to tie the knot they are fine.
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The spectra lines don't kink or break stands. I can't tell with the spectra lines, and I am careful to not have them abrade.
I am with you on this which prompts a question? Do they break under our load conditions? I have personal knowledge of only one case of Spectra lines causing a crash and that was from a poorly tied improper knot.
Ken
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My experience with them is very limited- I've used them some on Classic size/powered airplanes for a few flights. Can't say I could FEEL too much difference and I think they are fine in most respects. I use them now on the grandkids airplanes mostly since they aren't too careful with the lines sometimes so I don't worry about them screwing them up. My one BIG negative when flying is that I CAN SEE THEM and it is very distracting to me. The lines are showing me things that frankly I'd rather not know about in maneuvers. The incredible bow in the lines from the handle to the airplane is discerning especially when I feel the airplane is pulling plenty and not having any line tension issues. Something tells me it wouldn't be too hard for a sharp-eyed judge to get fixated watching the lines as much as I am flying......
Dave
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I am with you on this which prompts a question? Do they break under our load conditions? I have personal knowledge of only one case of Spectra lines causing a crash and that was from a poorly tied improper knot.
Ken
So I made up 10 short lengths and hooked the up to a bucket and kept adding weight till the line failed.
I did it 10 times. It failed well above the rated strength and never at the knot. Not scientific but it was 2x I would ever expect.
The only failure I had was a plywood lead-out guide abrading the lines, and they popped. This is on a speedy slow combat plane. I hit weed on take-off one time it flew across the circle and jerked the lines tight. The lines did not fail but the belcrank pivot bent.
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Lauri, I don't know you from Adam.. And you are probably a far better flyer than I am, but your conclusion is not supported by your premises.
Just because you haven't seen them used, does not make them "for sport flying" vs "More serious use".
That attitude itself indicates a measure of presuppositional arrogance not grounded in fact, and that is exactly the kind of thinking that is killing control line and stunt.
Control line, Stunt, is far too important to be treated so sanctimoniously.
So please re-think your comment and provide some useful feedback.
Dan's and Gerald's comments are far more useful, and at some point, when you "big boys" have someone in your echelon who registers a few wins with them, all of a sudden, there will be a switch, and "serious flyers only use Spectra lines, those old fashioned steel lines are for less serious and less important sport flyers."
Mark
Actually, Lauri has been to several World Championships where almost everybody was using Spectra line, AND he is in fact a WORLD CHAMPION in that event (F1A Glider). Deserves much respect for being a WC competitor in not only one event, but two very different events, AND making his own airplanes for both events and engines for F2B. I think a lot of the WC F2B fliers use the brass plated 3 strand lines from Ukraine, which are reportedly the bee's knees. H^^ Steve
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I think a lot of the WC F2B fliers use the brass plated 3 strand lines from Ukraine, which are reportedly the bee's knees. H^^ Steve
That is what I was using when I switched to Spectra. I rate them equal. I can get 300yards of Spectra next day on Amason. That is the difference.
ken
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I am with you on this which prompts a question? Do they break under our load conditions? I have personal knowledge of only one case of Spectra lines causing a crash and that was from a poorly tied improper knot.
Ken
At least in free flight the most common reason for line break is badly prepared knots. Trust me, I propably use more of these lines (not exactly Spectra but similar) than the Stunt Hanger alltogether.
We hear it all the time from people want to use the same line as me, and then complain when the lines keep breaking. Some even think that they are so much stronger that they need stronger lines😂.
As I said earlier, I use Uni Knot. I think it’s the best because the line doesn’t make sharp bends inside the knot.
But whatever knot you use, the line MUST be slowly pulled to nearly maximum tension before using. I pull my #150 and #200 lines very slowly to about 30kp load and keep it there for 30 seconds, and repeat that 3 times. Then the line is ready for use. If you don’t do it, the line WILL break from friction heat at the first launch or sudden stronger jerk at about 15-20% of the maximum load. L
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Lessons I learned with Spectra:
1) Do NOT use pliers of any kind to help form a knot. I used flat-jawed pliers on one set of lines I made, thinking I’d be safe, and lost a model due to a break right at the knot. I have another set that I made without using the pliers (by hand), and they’re fine.
2) Jim Hoffman's advice on not using them on heavier models is wise. I went back to a braided steel line for my larger planes.
3) Use Dennis Adamisssion’s video as a guide. It is excellent.
Hope this is helpful.
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I have been using PowerPro brand spectra lines almost exclusively for 4 years. (Can't speak to other brands.) I make up the lines per the video and I have not had a single failure to date. Not even on my heaviest 63 oz Vector 40 model (80 lb rated lines used).
IMO, if the video is properly followed when making up the lines and using the double loop knot, and the lines are pre-stretched to about 1/3 of the rated load, there is no problem with the strength of the lines or knot.
Even a relatively heavy model will have only a 10-15 lb pull load in level flight. That is only 5-7.5 lb per line. And with a double loop, only a 3-4 lb load at the connector.
Even a model 40 lb pull test is only 20 lb per line. Still a safety factor of 4 on 80# rated lines.
If lines have failed in flight, it has to be due to an improper knot, damaged lines, or poor-quality spectra material from the factory.
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Lessons I learned with Spectra:
2) Jim Hoffman's advice on not using them on heavier models is wise. I went back to a braided steel line for my larger planes.
Why would you not use them on larger planes? I have not had a single issue on two planes over 65os and one over 70oz. The only wire lines that are even close are the 3 strand Ukraine lines.
Ken
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Several of my larger planes (up to 68 oz. Predator) have been flown on Spectra but I prefer steel cable for the heavier models because the Spectra stretch hinders the corners IMHO. The difference is subtle, but I can feel it
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Hello My two sons Otto and Max have now spent most of their lives flying on Spectra and prefer it to steel but they are still required to use it for Team Race and Combat (due the ban on mixed types) . The brand you use makes a big difference and Power Pro Max Quatro and Shimano have been our favorites and our line failures have been a lot less then steel especially flying combat. Biggest model I have flown (72oz), I felt happier using Spectra than stainless.
Regards Gerald
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On a small private flying field I have access to, noise issues restrict me to a maximum of 1.5cc diesel engines, generally in 30" span own-design Flite Streak clones. For adequate line tension in the overheads, I'm restricted to a maximum of 42 ft. steel lines (the tinned 3-strand British variety), but using the thinner, lighter 15 kg. (approx. 33 lb.) Spectra I can go up to 48 ft. line length without trouble. As I'm less nimble than I once was, the slower lap times are very welcome, and for me that's the big advantage of Spectra - not to mention its cheapness and ready availability.