Round Lip Vs Square Lip
35 replies to this topic
Posted 12 August 2011 - 02:41 AM
Great work Dave. Thanks you for sharing. I love data.
Are sample A's numbers correct? Visually the square bill looks to have more surface area.
Posted 12 August 2011 - 03:52 AM
I could not feel any difference. This whole project was about finding more thump in the lure and because I could not feel or see anything, I did the above video. Again, the problem is remembering the feel and then trying the next lure for camparison. I guess I am just not sensitive enough.
I have the coffin and another lip under construction (with black lines), so probably tomorrow, I will hit the tank again, make some more vids and try to feel the differences. I think the important thing is to remain objective and honest. If these differences are discussed by pro's in articles, I would expect to see or feel a distinct difference, but I am not going to report on something that I cannot feel. As for seeing, I will present the evidence for you guys to make up your own minds.
Posted 12 August 2011 - 05:21 AM
Vic - sorry, missed your post. Yes, the numbers are good. Probly an optical delusion.
Posted 12 August 2011 - 05:31 AM
we use the squre lips on our cranks for musky. not creating controversy but lip angles along with lure weights are a big factor here. another variable is legnth from pull tie.. the major preference is a lure that walks side to side without blo-out at desired speeds .. on a larger model we have a fall 11 inch bait with a rounded lip. its counter-balanced and dives to 29ft with 40ft of line out, trolling at 3.5mph. the variables create depth and wobble along with lip factors.
no easy etched in stone deal here.
Posted 12 August 2011 - 05:48 AM
Absolutely, couldn't agree more.
The development lure is the round lip. Using the customers lip, as he has a stock of them and also the customers body profile, I moved the other parameters around until I achieved what I considered the best action. All the lures under test are as close to identical that I can get. The same block of timber (albesia) was used, the same template and a gram scale for the ballast. So if anything, the round lip should perform better, as the lure was set up for it. Still, there will be build errors, so even a small difference in performance will hardly be conclusive, I would have to do more builds just to confirm. This could get out of hand.
Vic - here is an overlay of the two profiles. It may help you see the areas better.
Posted 12 August 2011 - 07:29 AM
The overlay really gives clarity.
You may want to try braided line to help feel the lures action when tank testing.
Braided is way more sensitive.
Posted 12 August 2011 - 01:34 PM
Round versus square: Here's a Sisson P-20 deep diver which has an essentially square lip but dives and swims nicely. Come to think of it, it resembles the lip on a Hellbender except for being square versus scalloped at the end. No doubt different lip shapes tend toward different swim characteristics and it's worthwhile to take that into account if you want the whole design to come together harmoniously. But don't get too focused on one design element. Everything counts: shape, length, angle, line tie position, thickness, and how much the lip width exceeds the width of the bait body. I'm leery about "rules" concerning lip shape because I see so many successful exceptions. But as usual, Dave's experiment provides useful information that you should consider in your own designs.
Edited by BobP, 12 August 2011 - 01:37 PM.
Posted 13 August 2011 - 12:03 AM
I'll second that Bob. When we change lips on a lure body and keep all other factors constant then that would reflect what different lip shape's effect on that particular body and no more. When I am designing lures, I always treat each as a complete system. Although prior knowledge and experience with what particular lip shapes can do will influence the choice and act as a starting point; keeping an open mind is important to keep us from being stuck in the perceived function of a particular lure shape.
Posted 13 August 2011 - 05:40 AM
BobP and LaPala – valid point about designing the lure for the lip. I did acknowledge this fact in post No25, but the mammoth task of developing four lures was more than I was prepared to take on. This exercise was more of a spin-off from what I was already working on. When considering the videos, the above point should definitely be kept in mind.
Continuing from the previous video (round square lip comp), in this video I compare four lip profiles: round (7) square ( coffin (9) and shaped (10). Sorry about the length of the video, I crammed it as much as I could. Even the music track was not long enough.
Visibly, the round (7) and square ( were very similar and had a much wider action than the coffin (9) and shaped (10), whose action was rather thin. The shaped lure had quite an erratic action, as can be seen in the under water clip.
As for feel or thump, I spent quite some time on this and concluded that the square lip had more thump than the round, but there was not that much difference, but still noticeable. The coffin lip was a distant third with very noticeably less feel. The shaped lip came in fourth with slightly less than the coffin.
It is tempting to introduce a discussion about the various features of the lip profiles, to determine or theorize about what exactly causes the action and the thump, but maybe better saved for another thread.
I will have to add to my list of future projects, some way of measuring the ‘thump’, as this important characteristic was quite difficult to assess manually.
I am now officially sick of flat sided baits and looking forward to moving onto another project.
Posted 13 August 2011 - 08:54 AM
Thank you Dave.
Your work has not gone in vein. I for one
now know considerable more about the lips
I am gluing to baits. And have a much better
idea which bill to use on a lure depending on
intended use. Thank you........Vic
Posted 13 August 2011 - 10:48 AM
Laughing @ The Adult Videos ,
Thanks For The Laugh & Great Info On The Lips.
Posted 15 August 2011 - 12:23 AM
Though I don't really have something to add to it , .........a very nice thread and discussion , ......thanks a lot for sharing your experiments , Dave !
greetz , Dieter
Posted 22 August 2011 - 06:00 AM
Awesome video Dave, Thanks for sharing!! I will definately be looking over this thread, the next several days, trying to figure out what lips to use on the baits I carved.
Posted 20 September 2011 - 11:34 AM
Playing catch-up on this thread, thanks for posting. What type of wood are you building these baits from? Very nice video, thoroughly enjoyed the music, sir.
Posted 21 September 2011 - 02:43 AM
Glad you liked the vids, I have been having fun experimenting with the music.
The wood that I settled on is abache. It is a medium density, around 0.5 specific gravity. It has good strength around the hinge pins, shapes nicely and seems to swim not so bad either. This wood is readily available to me, being a common building material locally.
The type of wood that you choose has no effect, it is all about the density, but I have found that even this does not have a significant effect on action. The beauty of a heavier wood is that less room is required for ballast. Don't get too heavy though, as ballast is required.