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Showing content with the highest reputation on 03/26/2019 in all areas

  1. 2 points
    Rather then claim to know what is fact, I thought I recount my experiences and what I've been taught about linseed oil, tung oil and varnishes. My first experience with linseed oil was my grandfather showing me how he maintained his garden tools. Every Fall, he would coat the metal and wood before he put them away for the winter. He also used it to help prevent rust by coating the bed of his pickup. I don't know if he used raw or boiled, these lessons were before I was ten, and by the time I would have asked, he had passed on. Along with my grandfather's uses, my great uncle fed raw linseed oil to his livestock. While I've used linseed oil most of my life, my first real learning experience with linseed oil and finishes was the years I worked on wooded sailing vessels. As one might image, we used a lot of linseed oil, various vanishes and every boat had it's secret formulas for deck oil, spar varnish, and rigging tar. Of course, they were really all the same, but folks like to feel as if they have special knowledge. The boats left me with a good base of knowledge, and a healthy dose of skepticism. Beyond the boats, my own use of linseed oil is pretty basic, I use it the same as my grandfather, putting a coat on all my garden tools and I use it on any wood surface that I don't paint. All my craft show display boards and walls were finished with linseed oil. I like that dark yellow finish that you get with time. Light wood is a nice contrast with black iron but every scuff shows up, with the wood a little darker, not so noticeable. Most of the time, any furniture I refinish gets a linseed oil finish. The exception is when I don't want the wood to darken, then I'll use tung oil. But the devil's in the details, just how to use linseed oil and what's all this other stuff on the shelves? First off, one can not use linseed oil without thinning. It's simply too viscous to do much beyond sitting and turning into a sticky mess. If I want a nice finish on wood, I build up the finish in progressive layers. I start with linseed oil thinned out 1 to 4 ratio oil/thinner, finishing with a 4 to 1 ratio. I apply each and allow it to start to dry and then wipe off the excess. The first couple applications will not need this, as they're so thin as to almost appear not be there. If I want a hard durable finish, I'll then apply a top coat of varnish. Putting on linseed oil in this manner gives the finish a bit of depth. It also acts in the same manner for the varnish as does primer to paint. Having wrote that, most of the time, I just need/want a simple finish and will use linseed oil and thinner mixed in equal parts. Paint it on and after a few minutes wipe off the excess. I do this because it's easy. No prep work, no need to sand and if it gets scuffed up, I can reapply in the same manner. For iron, I'll use the 50/50 mix and do the same as with wood, let it start to get sticky and wipe off the excess. Let it dry and reapply. If you keep the coats thin, they will dry in a few hours. I'll do this several times to get a bit of thickness to the finish. I can not over emphasize, you have to wipe off the oil. If you don't, it will take a long time to dry. But for the most part, I no longer use linseed oil on iron. It's not long term waterproof, so it's no good for outdoor finishes and clear paste wax works just fine for indoor finishes. I've got coat racks I waxed 12 years ago and even with all the wet chore clothes I've hung from them, the finish is still good. I don't use tung oil very much, but just thin it out and put it on the same as linseed. Don't know if this is the correct method, but it appears to work. I've also been told and my experience bears this out, Tung oil is heat resistant enough to use on fireplace screens. Now about the other stuff. When talking about drying oils, there is no other stuff, there is only premixed/thinned/dryers added oils and the marketing companies do to make their mix attractive. I sure there are other drying oils out there somewhere, but most of the time, the only oils you will find in any mix is linseed, tung, and modified soy oil. Soy being the most used, as it's the least expensive. All will have a bit of linseed or tung oil to be able to make the claim. Formby Tung Oil Finish is an example of this, mostly soy with a bit of tung for the marketing claim. Some are thinned versions of the oil and some are very thinned varnish. Danish oil being one of the thinned varnishes. Bear in mind, I'm not knocking these products, they all work and some of them work quite well. Look at Tru-Oil, it's 4% linseed oil, 10% soy oil and 86% thinners and solvents, yet people on this forum speak highly of it. Penetrating oils, I've used them on floors but really don't have the experience nor knowledge to say anything about them. Spar varnish, what is it? In it's simplest form, it's linseed oil with some type of resin. For ship use, spar varnish needed to be more flexible then the varnish you would use on furniture, so the ratio of oil to resin was higher. Now days, it's a generic term for any outdoor varnish. I spend the last few weeks reading articles on the net. Lots of opinions, not much useful information. But one stuck in my mind. Here's a slice of it: “Every now and then someone comes into my shop, and in the course of conversation volunteers to me that his (it’s always a him) family had a secret formula for a finish that had been passed down for generations. Of course he wasn’t going to share it with me because then it wouldn’t be a secret anymore. So I would have to tell him what it was: 1/3 boiled linseed oil, 1/3 spar varnish (I never understood why it had to be spar varnish and not simply any varnish), and 1/3 turpentine. Now we might use mineral spirits (paint thinner) instead of turpentine, but this was an ancient formula, surely before there was mineral spirits. Surprise on his face. How did I know? Adding varnish into linseed oil is a way to make the linseed oil a little more protective and durable – not much, but a little. Doing this goes way back, at least well back into the 19th century.”
  2. 2 points
    I've had the small hunter done for a week or so and just finished up the bow tie ax today. The hunter has a 4" 52100 blade, salvaged steel and wrought iron fittings and a sambar stag handle. 8" overall. The ax has a 1065 head and oak handle.
  3. 1 point
    I like the shape of that Kukri, I have been meaning to give one of those a try so I am looking forward to see how yours turns out so I can hopefully get some ideas on how I want to go about my own... And that pocket bowie looks like its off to a great start.
  4. 1 point
    Morning guys, here's some pics of this latest hunter off the bench. It's a bit of an unusual one for me. It has an L-3 (52100) blade, 120mm long, 4mm thick on the spine, overall length 255mm, brute de forge finger choil, Macassar ebony scales, inlayed with two bone escutcheons, with red liners held by two S/S Corbies, wet formed deep pouch sheath, dyed golden brown with a Moran style smiling moon in nickel silver.The reason for the Bill Moran theme is the pieces of bone were bought by the client from the shop sale after Bill Moran passed away so these with the forged finger choil and moon were added as a homage to him. All questions and comments greatly appreciated. Steve
  5. 1 point
    This is a common problem for woodworkers. There are a couple ways to solve this. One is using a paste wood filler, like Pore-O-Pac made by Behlen. Here's a link to the Woodcraft page that explains how they are used. https://www.woodcraft.com/blog_entries/pore-fillers They are applied before you put on finish, so it's a little late for your current project, but may help you in the future. I haven't personally used them, but they sound like they are what you might be looking for. Another trick, which may help you now, is to apply the oil finish you're using and immediately sand it, while it's still wet. This will create a slurry of oil and sanding dust, which will get worked into the pores. Let it sit for about 15 or 20 minutes, then wipe off the excess, but not too aggressively. After a couple of coats you should build up enough filler in the pores to get a smooth finish. I've found that after each coat fully dries I like to sand with 320 or 400 grit sand paper, otherwise the finish looks a little muddy if you let the slurry build up too thickly.
  6. 1 point
    I thought it would be advantageous to have a thread to reference for the benefit of beginners (or anyone under equipt). In this we are only going to look only at our beginner safe steels. Being that I am highly underqualified to direct anyone on metallurgy, correct me at will, and add what you think, or any questions! First up; steel selection . What makes a beginner safe steel? The answer is to keep it simple. A general rule of thumb is the less complex the steel; the less complex heat treatment is (with exceptions). High chromium steels who's carbides require long soak times in order to get into solution are not safe for beginner's. However, Alloys like 5160 with a moderate amount of chromium are easy for beginners to use and are a fan favorite for its attributes such as toughness, wear resistance, and edge retention alongside harder to heat treat steels like 1095. Alloys like vanadium can actually help keep grain size small. Manganese can have an effect on the depth of hardness. Low manganese steels are shallow hardening (use for hamons) and classified as a water quenched steel (don't try water). Higher manganese steels are deep hardening and classified as an oil quenchable steel (definitely don't try water). A lower-high range of carbon content (.75-.84%) can use a slower speed quenchant (such as 120°F canola oil) and are less sensitive to overheating. So our favorite begginners steels are: From the 10xx group: from 1075, 1080, and 1084. Unrelated to those; 5160, 80crv2, 15n20. How to work these steels There is no doubt some will want to try forging a blade. Anything heat wise you do to a blade is a part of its heat treatment. These steels need to be forged at what I see as a high orange color to a mid orange color. To me, red is around 1,100°F- 1,300°F. Don't forge anything more than to straighten a blade at this heat. You want to be at a temperature of around 1,900°- 1600°F for forging. This can be tricky to go by. Some claim the steel is "cherry red" others claim it is yellow or orange. We all see it differently. Normalization It is next, but not until we learn the big word below. Decalescence "De"as a prefix means "to be away from", or "without" and "calescence" means "to warm up" in Latin. So, "decalescence" means (roughly) "to be without warming up". Since energy is matter, and matter is energy; the steel will release light and heat energy When heated. When you heat the steel to a certain point, the steel begins to change its atomic arrangement. Such a change requires energy to accomplish, so the steel cannot emit its light energy, and heating may slow down. This creates a visible "shadow" in the steel that can be used as a waypoint in the normalization and hardening processes. Recalescence is the same thing as decalescence but in reverse. So you see it as the blade is cooling. Here's a video by our own @Wes Detrick (hope you don't mind Wes ). For a closer look, I'm gonna quote the guy who explained it to me in another thread; Alan Longmire. "It's not heat, nor is it grains. It's photons and individual crystal structure. When the crystal goes from face-centered cubic to body-centered cubic it takes energy to accomplish, thus the momentary darkening. It does not cool off (much), and when it brightens again after transformation is complete it is because the photons are being emitted again rather than absorbed. Exactly the same thing happens in reverse when you heat it up. The swirling shadows you see are the crystals transforming from body-centered to face-centered, absorbing energy. This is the dimming via lack of photon release, it is not cooling off. We're in the realm of subatomic phenomena here; where visible light is due to electrons jumping up or down one step in energy level, releasing or absorbing photons in the process. Matter is energy and energy is matter, light becomes solid and vice-versa. E=mc^2 and all that. Grains are just groups of crystals growing in the same alignment, not unlike quartz crystals. You can have big ones you can see or tiny ones you can't, but that make up a large mass anyway." So, if you couldnt make sense of that; the steel darkens or forms a "shadow" at the temperature right before you would be ready to quench. You continue to heat the steel until the shadow brightens until it becomes the same color as the area just outside of the shadow. You want to heat as evenly as possible until the shadow is gone. Heat thicker areas first, and then move to thinner areas. I pull my blade in and out of my forge's hot spot to achieve even heat. Some use a pipe capped on one end inside of the forge to create an even heat. This phenomenon is best seen in low light conditions and is used for both normalization and hardening. Normalization continued We're going to skip annealing as I see it as unessesary and difficult for a beginner to accomplish. To soften the steel for stock removal and drilling as well as grain refinement prior to hardening; we normalize. Using decalescence, we typically (using these beginner steels) run 3 cycles to refine grain after forging or annealing. To do this, you take the first heat a little above "critical" (the point after decalescence) and let cool in still air until no color is left. I typically quench in oil at this point, others like to wait until it's just about cool enough to grab. Then, another heat is taken to right at critical temp and then allowed to cool in still air. Lastly; the blade is taken to a dull red heat and allowed to cool in still air. Note: if this project was taken to welding heat or fully annealed more cycles of normalization won't hurt. I typically do 3 sets of each cycle above. Hardening This is just about the same as the second step of normalizing with the addition of quenching. The above steels can all be heat treated using canola, or peanut oil. You'll need to heat the oil in a metal container to around 120°F. I judge this as uncomfortable to hold my finger in for more than a second. If you wanna get fancy; buy a meat thermometer. Scrap metal can be heated and dunked in the oil to heat it. Have your oil warm and just a step away. Heat your blade to critical, and without lollygaggin, put it tip first into the oil and make slight cutting motions through the oil with the blade. Wait 12 seconds to pull it out. Any warps you have can be fixed in the temper. Tempering This is what softens the brittle blade and should be done immediately after hardening. The right temperature for tempering should be decided with the design of the blade in mind. A blade with a lot of force and leverage applied to a robust edge should be tempered hotter for toughness. A chef's knife might be left harder to maintain an edge longer. This is a compromise between toughness and edge retention. You can temper in a toaster oven, a conventional oven, or even a real tempering oven. If you choose a conventional oven or toaster oven, use a meat thermometer to measure heat. Most ovens are out of calibration, and have temperature swings. To combat this; use a heat sink such as a tray of sand, or a firebrick. Flip the blade each cycle. The cycles should be one hour minimum for 3 cycles minimum. I do three 2 hour cycles. Leave it alone for one cycle, take it out, and quench in water. Repeat that until you are done. The point behind cycles is: When you harden a blade; you heat it to critical which forms a grain structure called austinite. The austinite is converted to martensite when quenched. Some austinite is left. Retained austinite turns into untempered martensite while tempering, so you temper in cycles just to try and get everything tempered. Now you're done!
  7. 1 point
    That's a hearth melt, not a smelt (since you started with steel and not ore), and that kind of bandsaw blade is more likely to be a 4xxx-series band with HSS teeth. If it's monosteel it's often 1095. The ones that they use 15n20 and L6 for are 9 to 12 inches wide with great big nasty lumbermill teeth. All that said, I think I'd give that a miss next time.
  8. 1 point
    I learned very quickly to do 3 normalization’s before the final heat up and quench. I do my heat treating during the day so it’s kind of hard to see the descale happening. But I manage then it’s directly into the oven for temper for me. I use a black and decker toaster oven it works great for smaller blades. I’ve only done the one two hour temper cycle though.
  9. 1 point
    Spent the weekend making these. A holding block for a knife out of curly maple and walnut. And a big 12x18 cutting board that’s glueing right now.
  10. 1 point
    Hi Charles Thanks for your comments buddy, here are a couple more shots of the knife from underneath, hope they help.
  11. 1 point
    I don't put the cutler's rivets in until after the epoxy because unlike a corby bolt, you don't have much room to sand into the head of the rivet. Therefore the surface of the scale has to be pretty close to the final dimension before they go in. I felt the rivets I had in stock were either too small or to large for this handle so I took some of the larger ones, and turned the heads down to 1/4". Then it was just a lot of rasping, filing, and sanding to get the final handle shape. Here is a quick snapshot of the mostly finished knife. I need to do a few touch-ups, and get some glamor shots done.
  12. 1 point
    Hopefully I can get out of this hospital tomorrow. The pain is going down a little. One bonus is I had a beautiful nurse last night another bonus of forged in fire all day
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