Heating A Wooden Lure Before Sealing
13 replies to this topic
Posted 12 November 2010 - 10:17 PM
I was playing around with some balsa and trying different things to more or less experiment with it. After spraying a piece with Createx I ran the heat gun over it lightly to heat set the paint and I noticed bubbles forming in the paint. Now this piece of balsa had not been sealed prior to painting so I can only assume that the heating of the wood was causing the air trapped in the wood to expand and the bubbles were being formed as the expanding air was trying to escape. I'm just wondering if this could be used to our advantage? Would it be feasible to heat a lure right before sealing it so as it was cooling the sealer would be drawn farther into the wood? If this has been discussed before I apologize. I did a search, but didn't find anything. That's nothing new though as my searching skills suck. I can never seem to type in the right phrases.
Posted 13 November 2010 - 12:08 AM
I think you can certainly do that but the results depend on the kind of sealer and the application method you use. For instance, if you plunge a heated blank into a jar of low viscosity sealer and hold it there, it will soak up the max amount. If you brush the same sealer on a hot blank, it would also draw it in but you might be left with rough areas where all the sealer was drawn into the wood, leaving little of it on the surface. Some guys submerge blanks in sealer for long periods. It takes longer to dry out and you may have problems if it isn't dry and you use a solvent based topcoat later. I just want a strong, waterproof, smooth surface to paint for bass baits. If the sealer is strong enough to prevent expansion bubbles rising from the wood when I heat dry paint, I'm happy.
Posted 13 November 2010 - 01:22 AM
I think you are correct in your thoughts. I have read on another forum (dont know if allowed to post so wont) exactly that, heat the bait to expel air and dip in sealer straight after and sealer will penetrate deeper into the bait. Now I have not tried it personnally so dont know any of the fine details and cant find the other post at the moment, but I would think it works. Me personally I dont worry about it cause I vacuum seal them, but I would think it work for you if you tried it.
Posted 13 November 2010 - 01:50 AM
Thanks Bob and Angus. I haven't actually sealed any baits yet or even decided on a sealer. I'm still experimenting with different things and trying to decide on a system that I'm comfortable with. I was just amazed at how little heat was needed to start forcing air out of the unsealed wood and after thinking about it I figured if you could force air out of the wood by heating it then maybe you could make the sealer go deeper as it cooled. I think I'll try a couple pieces of balsa cut from the same blank and see what it does. Sealing one that's been heated and one that hasn't and then cutting them open to see if I can tell if there's any difference.
thanks again guys,
Posted 13 November 2010 - 08:04 AM
The one thing I would say to take into consideration is whether you want a lot of sealer soaked into a balsa lure.
I think the air that is trapped in the woods structure is key to it's buoyant, lively action.
If enough sealer is soaked up, I think it might change the characteristics of the lure, as opposed to a shallow sealed balsa lure.
Have you tried thinned D2T epoxy as a sealer, two coats? Or propionate, several dips? Or super glue, two coats? All of those methods are used with success on balsa baits by forum builders here.
I only use a hair dryer for heat setting, so I don't know what a real heat gun is capable of doing.
Having said that, when I used to use a penetrating sealer, Minwax Wood Hardener, and soaked my blanks in it, I had to use my hair dryer on high to heat it afterwards and drive out the hidden, trapped solvent, which would show up as bubbles at the end grain.
Otherwise, the bubbles would appear when I heat set the paint job, and ruin it.
I found that the hardener didn't really protect the lure any better that the Minwax Poly Acrylic that I use before it, because it didn't make the lure any harder, so the wood was still easily dented, and the topcoat and paint scheme were easily damaged by water intrusion.
For balsa lures, since I don't make a lot of them, I use crazy glue, two coats in succession. It penetrates some, and makes the wood's surface much harder. Plus it's quick, and I'm impatient.
If I had to do a bunch of balsa lures, I'd use either the thinned epoxy (D2T) or propionate, which are both much more economical methods.
Just my 5 in the morning, too windy to go fishing ramblings.
Edited by mark poulson, 13 November 2010 - 08:06 AM.
Posted 13 November 2010 - 11:35 AM
Thanks for your reply. What you were saying about the air being trapped is exactly why I was thinking that heating the wood before applying the sealer might be an advantage. If you could force some of the air out before sealing then there should be less chance of bubbles appearing while heat setting. You could get the bare wood heated to a much higher temp than would ever be needed to heat set paint and this should keep any bubbles from forming while heat setting the paint. At least that's my thinking, but I have been known to be wrong even though I don't like admitting it. lol
I realize this could change some of the weighting and overall characteristics of the balsa. By how much? Who knows. Even with a slightly heavier and more dense balsa lure it should still have a much livelier action than a heavier and more dense wood.
I still plan on doing some tests to see how much deeper, if at all, the sealer will penetrate when the wood is heated. Right now I'm trying to think of something, like a dye, that could be added to different sealers to make it easier to see how deep they penetrate. Anyone have any suggestions?
Edited by RayburnGuy, 13 November 2010 - 11:37 AM.
Posted 13 November 2010 - 02:35 PM
I agree with your theory, heating the body prior to sealing will at the very least, give you better adhesion, regardless of the type of seal coat. My only concern would be gassing of the thinner coats, like propionate, as Bob mentioned. The same applies to vacuum sealing. This problem/concern only applies to seal coats that rely on evapouration. Resin and epoxy's that are chemical reaction, would not be a concern.
For evapouration processes, a closed box with a low watt incandescent bulb, for an hour, would solve the problem. Yet another application for my Plaster of Paris dryer project.
Posted 13 November 2010 - 08:44 PM
Pete, had an idea that have used in the past to get deeper sealer penetration. It involves a mason jar, lid, and a brake bleed.Place the bait in the jar with sealer in and have a hose comming from the lid to the bleed and start sucking the air out of the jar. You will see bubbles come from your bait, but this is not where you get the deep penetration its when you release and let the air back into the jar, the sealer gets sucked into the bait.
Posted 14 November 2010 - 02:14 AM
Rayburn Guy, I would agree with Mark Poulson, From 40 plus years in the building industry with 29 of those in teaching Cabinetmaking, characteristics of wood are odd. Some woods are considered open grained, like Oak and Walnut. While some are closed grain, like maple and cherry. This refers to their ability to be sealed effectively and not show open pours when the sealer dries. You can see the penetration by the color of the wood if you cut into the wood. But if you have a good bond on the surface of the lure why would you want it to go inside of the lure and add any weight? Wood shrinks, swells, warps, crooks and any other movement is caused by the amount of moisture content that changes in the wood. Moisture content rises, wood swells. Moisture content goes down and wood shrinks. Sealer soaking into the wood will cause the moisture content to rise causing the size to expand. It will dry inside and remain the larger size, even if very slightly larger. I believe it would work best to have DRY wood at room temperature until the sealer dries. This is just my .02 cents worth. Musky Glenn
Posted 14 November 2010 - 06:38 AM
Sealing wood and making it both waterproof and hard was my downfall when I was building jointed swimbaits out of wood.
I tried just about everything, with limited results. There always seemed to be a failure somewhere, and water got in.
Since I switched to PVC, I have cut several days off the building process, and the lures are totally waterproof and hard.
The decking I use is, AZEK, is buoyant enough for top water poppers, but it isn't as buoyant as balsa, so my PVC poppers aren't as lively as either hollow plastic or balsa, but they do work, and cast like a bullet with a baitcaster, so I am much more accurate with them, and can hit boilers at a greater distance.
I find the decking works and machines like wood, but you need sharp tools. And shaping it with an occilating sander works really well, but I have to use light pressure, or the plastic melts and gets grabby.
I'm saying all this because I've read your posts regarding musky and pike lures, and, although I don't fish for them, I think PVC would be a perfect material for lures for those toothy critters. It holds up to salt water fish really well.
Posted 14 November 2010 - 06:44 PM
Thanks for all the replies and info guys. I'm a little jealous of you woodworking guys and your knowledge of the different aspects of various woods. If any of you ever need a crankbait built out of steel just let me know. I promise it will cast like a bullet and get to the bottom in no time.
Edited by RayburnGuy, 14 November 2010 - 06:45 PM.
Posted 15 November 2010 - 01:59 AM
Ben, here is what the search feature came out with, for "sealing wood".
Can you believe that I have put the wooden blanks in the oven, and when they reached about 200 degrees Celsius or more, I dipped them one by one in propionate solution? Leaving each one to dry at room temperature for about 15-20 min, then putting them back in the oven? By doing this, the propionate solution sprang out of the wood places. After sanding the surface, I repeated the same process with the second coat of propionate, including sanding.
Now I,m done with such experiments. I'm happy the solvent did not explode in the oven.
By preheating the wood before sealing, you do not only make the air expand, but you also lower the water contents of the wood. So I think preheating the wood is good for the lure. There are many aspects that could be discussed here, but I won't, because they have already been discussed.
Posted 15 November 2010 - 03:24 PM
I give gentle heating of wood prior to sealing two thumbs up. When I still built wooden musky lures I used a penetrating epoxy called Rot Doctor. Never used balsa but plenty of basswood and white cedar. I heated the lures with a heat gun prior to application of the epoxy as it enhanced thinning of the product and allowed it to get drawn into the pores as the wood cooled. A second coat was needed to give it a little smoother base for application of paint as the first coat virtually disappeared into the wood.
Posted 16 November 2010 - 12:16 AM
Thanks guys. Not sure that I will even try to use something like this or not, but the thought was stuck in my head and I knew that if anybody would have any ideas about doing this it would be you guys so I just had to ask. Thanks again to everyone who replied.