It is pretty universal for manufacturers to give both lure weight ranges and line weight ranges for their blanks. (I'm talking mainly about spinning/casting/surf blanks.) I can see where it would not be too difficult to establish lure weights with simple deflection tests (not talking about CCS here). While I don't always agree with the ranges given, it would not be hard to devise an objective measurement procedure that could be applied to all the blanks in that manufacturer's line. (Again, I'm not talking about comparing with other manufacturer's rods.) But, the line ratings seem more problematical. I don't see how they rate for this. Doesn't seem that it has anything to do with a breaking strength. And it's very common to see a blank called a "spinning" blank, and given a rating of, say 6-12#, while a "casting" blank that in my hands seems to have very similar power will be rated 10-17#. To me, it seems more a marketing device based on what line anglers tend to use for spinning and casting rods, where the choice of line is actually more dependent on the reel. Am I wrong here?

No, I think you're quite correct. Line ratings, to me, are more for the average, somewhat uneducated fisherman (rod-wise, not intellect) who often need some sort of guidelines for helping them choose a line size for their rod/s. Most of us here on this board could pick up about any spinning or casting blank and give it a shake, maybe a quick hand flex and then proclaim something like, "This would cast a 1/4 ounce lure pretty well and probably match well with such and such size reel running 8lb line." But, the average fisherman, might well be lost without those ratings on the side of the rod or blank.


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I now make my own line rating stickers for the blanks that I COMMONLY build on; they are lower than the manufacturers' claims in all cases.

Putter

You might even ask the question of what do the line ratings themselves mean. Most lines, especially the ones targeted towardthe mass market are vastly underrated.

Just this weekend Roland Martin was doing a using a line that he was plugging (pun intended), and stated that it was the "strongest 6 lb. line on the market". Huh?

I haven't tested them, but I would guess that braided lines under 20 lbs. are at least twice their rated strength. 8 lb. braided sure doesn't break like 8 lb. mono.

I hear that Cortland now is offering some fly lines in 1/2 sizes, ie 3wt or 31/2wt. This seems like overkill to me.

"Test" lines are rated to break at or above their rating. "Class" lines must break at or below their rating.

So, a line that only breaks (on a steady pull) at a minimum of 20lbs could be labeled as being 4lb test. Or 8lb test, etc.

This is why one company's 10lb test can be "stronger" than another company's 10lb test. Just one more place where perhaps some real standards are needed.

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Mono filament lines almost always breaks at the knot first. The line itself is often stronger by 25% to 50% than what it is rated by the manufacturer but once you put a knot in it the strength drops significantly, 10% to 50%. And a number of line manufacturers, for marketing purposes, rate their lines lower so that we all think that we are really getting good strong line.

A couple of rod manufacturers are putting a maximum line rating the on their rods that is a function of the angle between the butt of the rod and the load on the rod. The load that a rod can take naturally drops as the tip is held higher and higher relative to the load. The manufacturers that rate the rods as a function of this angle rate them at 45 degrees. Or in other words if the rod is held at 45 degrees or less the line should break before the rod does, but at an angle higher than 45 degrees the rod may break before the line does. The problem with this system, as I see it, is it is not universally accepted and even those manufacturers that use it do not publisize it so that we are all aware of it. So I think that where we are is with a line rating on line and a maximum line rating on rods that is arbitrary.

The new no stretch lines also cause some confusion. When it first came out Musky Fisherman who were used to using 20-30 lb line were finding that they would break the line when they set the hook. They found that they had to go to 80-100 lb line in the no stretch or go to a more limber rod. In both cases the reason for the line seemingly was defeated. No stretch gave you a smaller diameter per line rating but if you had to use 100 lb line you were back to the same diameter. Likewise if you used 30 lb no stretch (For better hooksets)you needed a flimsier rod which canceled out the hook set power.

Tom, I think you're correct for the most part. Manufacturers make blanks to a line rating probably more so that use the line rating to configure the blank. The line ratings obviously with popular choices need blanks to suit those applications.
The other consideration is that lines differ also. There isn't exactly all that much uniformity in line diameter to breaking strength. Some lines can be over the breaking strength by quite a lot. It might be realistic to have a blank rated for something like 'mono line diameter equivalent breaking strength' or something like that. Some anglers also consider that a small diameter braided line works well on a rod because it fits the diameter criteria rather than a line rating. When, in effect they could be overlinging a 17 lb. (mono) rated line with 30 lb. braid line.
So, it's really that an 'average' can work when choosing a line rating for a blank. Also, consider that if you topped the line rating on a 10 to 17 lb. blank using 17 lb . line that is actually with a 50% higher breaking strength and the lure rating says it can cast a 1/4 oz. lure. In that case you may be underperfoming the cast because the line may actually be acting like a 25 lb. line, especially if maybe it's a higher memory or stiffer line. All these factors should be taken into consideration for choosing a blank for a certain lure and/or line application.

Rich Garbowski
Richard's Rod & Reel

info@rodreel.com

With a palomar knot, or similar, the line will always break before the knot. Not that this statement adds much to the discussion here, but there are some really good knots, and some fairly bad ones in terms of breaking strength.

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Tom,
I have seen the data on two different knot strength tests that showed that the knot is always the weak link. The palomar knot is one of the strongest but it is still going to break before the line does. It also depends a little on the line. As I remember the harder monofiliments tend to have better knot strength while the softer monofiliments tend to have slightly lower knot strength.

I've never had a palomar knot break. Now in many cases when fishing, it could be that the line is letting go before the knot because there is some small nick or bruise in the line itself, which constitutes a weak area.

However, at the AFTMA show in 1987, a rep from the Silver Thread Company was there with a knot/line breaking "machine." You tied a knot and slipped one end on a post and then the other end was wound and secured and then the machine turned on. It slowly rotated and pulled the line taut, while registering the amount of pull on a scale. After a few hours of watching his clinch knots break before the line (every time and at only about 70% of the unknotted line stregth) I suggested a palomar knot. He had never heard of it.

So we tried it and for the rest of the day he never got the knot to break before any of the lines tested.

I have no doubt that the hardness or softness of the line has much to do with knot breaking stength. So does the type knot and whether it slips or bites. But I would agree with you that in most cases, we should always consider the knot to be the weak link in the chain.

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I agree that manufacturers make blanks for specific applications and line ratings but the strength of the rod is very much a function of the angle that the load is applied. For example, if you hold a rod straight up in the air and pull directly down on the line the rod will break at a fraction of it's maximum line rating. On the other hand if you hold the rod parallel to the ground and the load is straight down or at 90 degrees to the rod the rod can handle line that is much stronger than the maximum line rating. The action of the rod will also affect this. A very high action angle rod will break at a lower angle between the butt and the load than a low action angle rod.
Almost all of the blank manufacturers talk about high sticking but they do it in a very general, qualitative way. I think that we would be better off if they would be more quanitative and maybe even rate their blanks line rating in terms of the angle between the butt and the load.

I think they would do ever better to furnish an "owners" manual with each rod or blank, citing these type things and showing fishermen what "not to do." It wouldn't take much room and could even be done on a simple header card for blanks and hang tabs on finished rods.

Because of the audience they must reach, they have to do these things in a very general, qualitive way, but even then they don't do a very good job of it. A large number of fishermen seem to believe that "good" rods are unbreakable and that if they do break, they must have been defective.

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For what it's worth....

I, too, have seen the line breaking machine demonstrations and the palomar knot held beyond the line strength tested every time. I pretty much use this knot for everything these days.

Joe

www.blackdogtackle.com

Well, we are off the original topic I posted, but thought I'd mention that one reason the Palomar Knot is so strong is because it effectively doubles the line where it joins whatever it joins. If you haven't noticed, take a good look at the finshed knot next time. Can't think of another knot that does this doubling automatically.

I'll go a little off topic too.

Initially, I though you were only talking about pound rating on lines, not on the blanks.

Blank line ratings should just be used as a guide - but that's been covered pretty well here.

On lines, I remember a pretty detailed discussion, with someone who actually tested line ratings on an instron.

Tectan was the only line out there that had 'correct' line ratings.

Without exception, all other line ratings were underrated (ie 8#rating broke at 11#, etc).