spoonbender

Specific Gravity Of Wood.....rayburn Guy's Thread...

24 posts in this topic

Rayburn Guy's thread about "Let me see if I got this right" post got a little long so will politely hi-jack it for just a second. I experimented quite a few years ago (70's) with laminating different densities of wood for muskie lures, specifically a Jake/Grandma's type. I was able to improve on the action, particularly the body roll by using hard maple for the bottom portion of the lure and basswood for the top part. The thought at the time was to give it a low center of gravity while still maintaining enough surface area without adding action dampening lead weights. Everything worked fine until the finish failed and allowed moisture to destroy the glue joints on the half dozen lures I built. After reading the fine idea's (and formula's) about SG's and COG's, I'm now fantasizing about resurrecting the project. With the better materials available today, might be able to get one to last longer than a couple years.

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That's a great idea Spoobender. Would never have thought about doing that. It opens up even more options.

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The glues we have nowadays are so much better than in the '70s.

I use gorilla glue to laminate wood for lures. Just be sure to dampen both surfaces first, so the glue is drawn into the wood, and clamp the two halves together until the glue sets.

Water may still present a problem with dissimilar woods, since they will probably have different coefficients of expansion, but that should only be an issue if the wood gets wet.

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Let me preface this by stating that normally, I'm a very easy going and accommodating person. It takes a fair bit of needling to get my dander up. Normally, I'd just restrain myself and not post anything inflammatory or antagonistic but no matter how carefully I word my post it will probably irk a lot of builders out there but this is how I feel about this. Whenever I read about the topic of specific gravity, mass and density mentioned in lure making, I immediately become enraged. I wish I could reach out and b.tchslap that person thru their computer monitor.

One of the reasons why I took up plug building was because of my acquired disdain for a certain west coast plug builder that was such a pretentious windbag. In every single post, he would always, I mean always say that he's the most extreme,best,toughest,knowledgeable surfcaster on the west coast. He kept reminding people of how he's been fishing for over 40-50 years and there's no one else as crazy as him; he mentioned this in every single one of his post. You might think I'm exaggerating but I'm not.

What really drove me over the edge was when he equated lure making with rocket science. His posts made it seem that he wasn't building regular plugs but he was building nuclear powered lures complete with flux capacitors with warp drive capabilities. It's a piece of wood with hooks fer cryin out load.

Specific gravity.......specific density........ how a bout a specific dose of reality. Please think about it. It's still wood. I don't care for that table that states each specific density, mass and weight for different species of wood. To me it's S.W.A.G. or scientific wild ass guess. Even wood from the same tree have different weights and density.

You say lure "A" is made from this wood and has a specific density of x. And lure "B" is made from this other type of wood that has a specific density of y. Therefore, if I were to add an z amount of weight, then the lures should sink and act this way. There is really no way of knowing how lure "A" and "B" will behave. There are too many variables. The only way you're going to find out is to actually make them.

But if your set on using tables and formulas and scientific theorems to build lures then might I suggest a much better use of your time would be searching for a cure for cancer.

Please, it's lure making nothing else. Keep it simple.

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Cereal Killer,

I guess that guy really got to you.

I agree that "it's just lure building", but different people enjoy it from different perspectives.

Different woods do have different characteristics. For me, knowing that lighter wood is more responsive is enough.

But some guys are intrigued by the actual differences in density and gravity. I don't think that should be a knock on them. It's just their way, and each of us has our own.

As long as we're not trying to shove our way down everyone else's throat, or driving others crazy with our "king of surf fishermen" B.S., I think there's room on this forum for all of us.

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Hey Killer, I understand where you're coming from. Lots of us have buttons that are more easily pushed than others. But I don't think your experience with an insufferable blowhard transfers - unless you're addressing the same blowhard. It's certainly true that no table of nominal wood density is gonna give you a number to plug into a ballasting formula for a crankbait. On the other hand, if you're sitting at your computer getting ready to order a batch of wood on the internet and don't have expert knowledge about different wood (that's me!), that table comes in awfully handy when it's time to choose the right wood. So when my box of basswood arrives from the vendor, can I expect it to have a density of 23 lbs/cu ft like in my table? Nope. Afraid not. Maybe mine was grown in a different climate, or came from a different part of the tree, or has more moisture than 7% standard from the table. But it does mean that, on average, I can expect basswood to be more buoyant than the oak I might have bought instead. And that's a big help.

Can you take physics too far in talking about crankbaits? For me and obviously you, yes. It gives me a headache sometimes. I'm a practical crankbait builder and most of my ideas are experience + intuition, not science. Get an idea, build it, test it, change it if it doesn't work. That's the way I like to work. But if physics helps a guy design a crankbait and understand why something works and something else doesn't, what's to criticize? The craft and art of crankbait making has room for at least a few different approaches. Please please don't b.tchslap me, Killer.

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Anyone want to try a top water bait out of Ebony which has an average specific gravity of 1.12, (Heavier than water) or a musky sinking glide bait out of Balsa which has a specific gravity of .2. It really does have a place. Musky Glenn

Edited by Musky Glenn

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Here's a thought. If you don't like certain topics then by all means don't read them.

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Here's a thought. If you don't like certain topics then by all means don't read them.

RayburnGuy, I meant no disrespect or insolence towards you. I'm truly sorry if it seemed that way. I happen to enjoy reading your posts. :tipsy::tipsy::tipsy:

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Cereal Killer,

I guess that guy really got to you.

I agree that "it's just lure building", but different people enjoy it from different perspectives.

Different woods do have different characteristics. For me, knowing that lighter wood is more responsive is enough.

But some guys are intrigued by the actual differences in density and gravity. I don't think that should be a knock on them. It's just their way, and each of us has our own.

As long as we're not trying to shove our way down everyone else's throat, or driving others crazy with our "king of surf fishermen" B.S., I think there's room on this forum for all of us.

Hey Killer, I understand where you're coming from. Lots of us have buttons that are more easily pushed than others. But I don't think your experience with an insufferable blowhard transfers - unless you're addressing the same blowhard. It's certainly true that no table of nominal wood density is gonna give you a number to plug into a ballasting formula for a crankbait. On the other hand, if you're sitting at your computer getting ready to order a batch of wood on the internet and don't have expert knowledge about different wood (that's me!), that table comes in awfully handy when it's time to choose the right wood. So when my box of basswood arrives from the vendor, can I expect it to have a density of 23 lbs/cu ft like in my table? Nope. Afraid not. Maybe mine was grown in a different climate, or came from a different part of the tree, or has more moisture than 7% standard from the table. But it does mean that, on average, I can expect basswood to be more buoyant than the oak I might have bought instead. And that's a big help.

Can you take physics too far in talking about crankbaits? For me and obviously you, yes. It gives me a headache sometimes. I'm a practical crankbait builder and most of my ideas are experience + intuition, not science. Get an idea, build it, test it, change it if it doesn't work. That's the way I like to work. But if physics helps a guy design a crankbait and understand why something works and something else doesn't, what's to criticize? The craft and art of crankbait making has room for at least a few different approaches. Please please don't b.tchslap me, Killer.

Anyone want to try a top water bait out of Ebony which has an average specific gravity of 1.12, (Heavier than water) or a musky sinking glide bait out of Balsa which has a specific gravity of .2. It really does have a place. Musky Glenn

Guys, I understand what you're saying. But here's what I'm trying to get across, a wood might have a specific density but once you start drilling, sealing, sanding, priming and painting. Adding eyes, rattles, weights, grommets, screw eyes and hooks. By the time you've added your final top coat e.g. Etex, DT 2Ton, Dick Nite. Then it really doesn't matter what the specific gravity of that piece of wood had. If all your doing is carving it and then just adding hooks, no paint, no topcoat, no weights. Then specific gravity might come into play.

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CK, I am truly sorry that you find techy posts so offensive. I have read all your posts and conclude that you are indeed a reasonable guy, very helpful and informative in your postings. I am sure that you don’t really want to bitchslap me, but if you did, you would probably have to get inline with all the other guys who hate techy posts.

Taking account of your username, relying heavily on the cost of airfare and the fact that I reside some 12,000 miles away, I am not going to be deterred and will continue to contribute tech if I see relevance. Best advice is not to read my postings. To help you filter out the offending literature, I shall include the word ‘tech’ as early as possible in the first sentence, so that you may skip my techy contribution.

To be honest, I expected more members to jump in here with full support for your tech outrage. But they probably recognized the tech content from the title and skipped it. I do actually understand your feelings, you are not the first to express them. It is actually something I do consider very hard, before posting tech and usually expect to receive some negative feedback. Sometimes I am very surprised and get none, even positive feedback for my work.

No offence should be taken now, but I am really hoping that Jerry will delete your post and the subsequent replies from this perfectly good thread, which I suspect is now well and truly destroyed. If this happens, you should start a new thread in the docks and lets all have a healthy heated debate on the subject.

Dave

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Dave,

I think pulling his posts is a little drastic.

We're all adults,and a big family here, and being able to vent and be heard by your peers without consequences is a part of what makes this forum so good.

I think, as long as it's not a personal attack, with intent to be nasty, and especially since he posted a clarification that it wasn't, we need to chalk it up to a "bad hair day", and move on.

Just my $.02, and I'm not sure what that's worth in Indonesia nowaday. ;)

P.S. Are you being affected by the volcano? Man, I hope it doesn't blow up. That would be a catastrophe.

And I wish Jerry would put spellcheck on the forum. It would sure help me look smarter! :lol:

Edited by mark poulson

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Guys, I understand what you're saying. But here's what I'm trying to get across, a wood might have a specific density but once you start drilling, sealing, sanding, priming and painting. Adding eyes, rattles, weights, grommets, screw eyes and hooks. By the time you've added your final top coat e.g. Etex, DT 2Ton, Dick Nite. Then it really doesn't matter what the specific gravity of that piece of wood had. If all your doing is carving it and then just adding hooks, no paint, no topcoat, no weights. Then specific gravity might come into play.

CK,

I disagree, and here's why.

A lighter wood, like balsa or pine, lets me put ballast low in the bait and get a very exaggerated action. When I want a really active lure, I use the lightest possible hardware, super glue for sealer, and one coat of urethane for a top coat.

For a shallow crank, lively action is critical, so the choice of wood is critical, too. Balsa and pine really shine for those baits. I use the lightest hardware possible for these lures, so I can play with the balast to get the action I want, instead of having heavy hardware dictate how the lure will perform.

Same for big walking baits, like the Lunker Punker.

I've made Punker knockoffs from fir, poplar, pine, and PVC. Pine is the best choice, by far, for a really active lure. All of the other choices work, but the pine lures are much easier to work, because they have less mass to move on each stroke.

With jointed lures, like swimbaits, I go strictly with the PVC, because it's waterproof nature and hardness make paint schemes almost bulletproof.

I'm lucky enough to have a load of wood left over from lots of years of doing residential construction, so I can pick and choose the kind of wood I need for a particular bait.

And I've learned a lot of the quirks of individual woods, like the fact that with teak, you have to wipe down surfaces with lacquer thinner or acetone before you glue them, due to the high oil content, and, even then, not all glues will work.

Or knowing how to pick woods with tight grain for strength and stability, but wider grain for lighter weight.

I know from working with wood over the years most of the characteristics of each species we work with, but many people haven't had my experience, so sharing knowledge about different woods, and how to pick a wood for a lure, is helpful for many here.

This is not meant to be a rant, so, if it comes across that way, I'm sorry.

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When it comes to building I tend to lean towards BobP in how I build, using the trial and error system. I also read all of Dave's posts although he is way over my head with the technical stuff.

BUT, of the handful of people on TU that I would love to spend a day with, either in their shop or mine, Dave would be near the very top of that list. If the only people you listen to are the guys who think in the same manner as yourself you can't learn a thing.

Show me two people who think exactly the same and one of them is not needed.

Edited by whittler

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Whittler said, "Show me two people who think exactly the same and one of them is not needed."

Now I understand why I was always getting fired! :lol:

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Mark, no problem here, I just wanted to try and rescue this thread. I have asked Jerry if he could split the thread and insert this subject into a new thread in the docks section. I think it could be a valid discussion, not necessarily one I would be looking forward to, as I am very passionate about what I do and the way I do it. As a design engineer, tech is a way of life. Hardly a moment goes by without me thinking of some project or idea that I am working on, fishing lures is only a fraction of what I am involved in.

This week, I have been working on a new type of turbo charger design, just got back from a shopping expedition to buy parts for the first prototype. I have drawn up plans for a ten piece cast iron production mold for a poured aluminium table, prototype complete and successful, have sales outlet waiting on this one. I have an invention in the early design process for an idea that could revolutionize the motorbike industry, can't give details. This morning I swam the first prototype of a baby sunfish body, moderate success, should have it nailed on the next build and a bit of techy analyzing. Also just done a couple of experiments with Husky’s silicon sealant. So you see, that a negative discussion on the relevance of tech in lure building would be hard for me not to take it personally, but I will try, but what ever the general opinion expressed, I cannot and will not change. I already pander to the anti tech lobby more than I probably should. For every techy post I make I have probably binned two more, out of prudence.

Whittler, I would love to have that day of shop talk. I am sure it will happen one day, when one of my projects pays out and I can finally afford to cross the pond and meet some of you guys.

As for the volcano, Merapi. It is two hundred miles away, but we are starting to get a thin film of ash on everything. Ironically, I was within a couple of weeks of moving to Yogyakarta, the city that sits in the shadow of Merapi. A lot of our customers and business contacts are based there, so it makes sense. I think the move will happen, but we have postponed the move until Merapi calms down a tad. Yogya is a volatile place to call home. It is subject to volcanic eruptions, earthquakes and tsunamis on the coast. It is not such a big deal, you just have to choose your location carefully, south side of the city and away from the coast, choose a small bungalow, not a high rise apartment building. On the positive side, property rental is a sixth of what it is in Bandung, a 3 bedroom house with garage, $500 per year. You can Google news ‘Merapi’ to see what is going on.

Dave

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Cereal Killer....you owe me a buck. That's what I just had to drop into the cuss jar after reading your post. First off, please let me apologize if my post offended you. I agree with you that some dudes get a bit full of themselves and it starts leaking into their forum posts, but it's pretty easy to just page down and get into more enjoyable content. I've yet to encounter anyone on this site that isn't here for reasons other than wanting to learn new ways and pass on their experiences for the benefit of their fellow man. I'm in a technical field and am accustomed to using technical terms to describe my thoughts/idea's, but didn't consider my use of them to be above anybody's head. Anyway.....no harm done, hope you have a better day. Next time you feel like choking me through the computer screen, just put down your highly caffeinated drink and step away from the keyboard......or give me a call and we'll go fishing. ;)

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Dave,

I personally always enjoy your technical posts.

You do the hard, time consuming work that most of us are too lazy (at least I am) to do, like extensive testing.

Sounds like you've got quite a few irons in the fire.

At the risk of adding another one, have you seen this lure, http://thinktanklures.com/Home_Page.html ?

I am intrigued. I've made a knockoff prototype, and have already had one unsucessful trial run. I've altered the ballast, and on my way out to try it again at the local pond.

A top water that is this erratic has to get murdered.

A really unique concept, I think.

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At the risk of adding another one, have you seen this lure, http://thinktanklure.../Home_Page.html ?

I am intrigued. I've made a knockoff prototype, and have already had one unsucessful trial run. I've altered the ballast, and on my way out to try it again at the local pond.

A top water that is this erratic has to get murdered.

A really unique concept, I think.

Mark, I have not seen that one before, very impressive. So simple, yet no one has done it before. Great design.

When I first saw the pic, I thought that the head was going to shake side to side. But after seeing the vid, it is obvious that the head gets stuck on one side, until the pause, then the head moves to the other side and repeat. It is the same forces that act on the lure when you 'walk the dog' or when you twitch a multi segment swimbait. But walk the dog, if you continue winding, the lure will pull straight, WTD only works on a jerky retrieve.

What result did you get off the first proto? How about a pic of what you have done so far. My guess would be that you have compromised with the flat head and not made the edges really sharp, because of the epoxy pulling away thing. Try gluing a thin lexan plate on the head, with filed sharp edges. Use a soft glue so that it can be removed if unsuccessful. Try a few different widths/lengths of plate. This can all be done at the waters edge, with a rubber cement.

Dave

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Well Dave, to paraphrase what Thomas Edison said when asked about all the "failures" that preceded his choice for the element in the lightbulb, I have eliminated another possibility. :lol:

Originally, I had not weighted the head, but, when the first iteration didn't work, I added a couple of grams of lead to the head.

Worse!!!

So I am drilling that out, and am going to add some weight farther back in the main body.

You're right, the head sticks to one side until the pause, and then goes to the other side, reversing the lure's direction.

At least, their lure does that. Mine doesn't, yet!

But it is an easy lure to make, and an interesting concept.

I didn't have a prop for the rear, so I just added a feathered treble. Maybe a prop adds something to the lure's action, too.

If I get it to retrieve okay, instead of leaning over on it's side, I'll start to worry about a prop. One thing at a time.

I'll try and post a picture in the gallery. I don't seem to be able to add one here. :(

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Well Dave, to paraphrase what Thomas Edison said when asked about all the "failures" that preceded his choice for the element in the lightbulb, I have eliminated another possibility. :lol:

Originally, I had not weighted the head, but, when the first iteration didn't work, I added a couple of grams of lead to the head.

Worse!!!

So I am drilling that out, and am going to add some weight farther back in the main body.

You're right, the head sticks to one side until the pause, and then goes to the other side, reversing the lure's direction.

At least, their lure does that. Mine doesn't, yet!

But it is an easy lure to make, and an interesting concept.

I didn't have a prop for the rear, so I just added a feathered treble. Maybe a prop adds something to the lure's action, too.

If I get it to retrieve okay, instead of leaning over on it's side, I'll start to worry about a prop. One thing at a time.

I'll try and post a picture in the gallery. I don't seem to be able to add one here. :(

I just posted some pictures of the lure in the gallery. It's 4" long, and weights 23 grams. It's made from PVC, and primed so I can see it in the water.

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My bet is that the designer is reading this and having a right chuckle.

Have to admit, I didn't see the lip first time around, but seems to me to be unnecessary, but I guess we should leave that for now.

Your head looks like it has a lot of movement. Maybe too much, causing it to 'dig in' rather than guide. Is it possible to restrict the side movement, maybe with a couple of blobs of hot glue.

Dave

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My bet is that the designer is reading this and having a right chuckle.

Have to admit, I didn't see the lip first time around, but seems to me to be unnecessary, but I guess we should leave that for now.

Your head looks like it has a lot of movement. Maybe too much, causing it to 'dig in' rather than guide. Is it possible to restrict the side movement, maybe with a couple of blobs of hot glue.

Dave

Good idea! I have to admit I would never have thought to try that, but it makes sense.

That's the beauty of using sst screw eyes for hinges. I can just tighten them up a turn or two.

I think you're right. That head shouldn't need too much side to side movement in order to achieve a change of direction.

I'll try it tomorrow, and let you know how it works.

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