EDL

As I continue reading through the threads on forge building, I am wondering about the affects of flux (borax, specifically) on the refractory. I understand it tears it up over time, but the question is what sort of time period are we talking? I understand this is relative. If I use Kasolite as the refractory and I were forging, say, a pattern welded billet with borax flux 2-3 times per week, what sort of time frame could I expect the forge to last? Sure, there are other factors, but just trying to get an idea...are we talking a week, a month, a year? (Trying to gauge just how damaging the borax is over time). Would casting some Kasolite forge floors in a form that could be removed and replaced be the ticket, or is Kasolite too brittle in thin (1/4", 3/8" thick) "plates"?

Ok, done with this. It would just be arguing at this point.

Understood. I went on the assumption that a "knife making" forge would be toward the smaller side considering general dimensions of knives (length and width). Of course, that still leaves room for interpretation depending on how big the knives are to be made, or other things but...I believe you've answered the question well enough. Ribbon burners become tricky in smaller forge sizes. At this juncture, I'll file that under the category of "don't try it on my first forge."

Having a very basic understanding of a ribbon burner (naturally aspirated or forced induction), are they worth the effort for a knife making forge? I'm aware a forge will require maintenance and possibly a rebuild at some point, particularly when using the borax flux common with damascus as it's nasty to the forge internals. I'd just like to have a better understanding as to the pros and cons to determine if it's worth the time and effort, or to stick with a simpler burner design, either for the above reason or others I'm not aware of. I'd like my first build to be at least decent. I don't mind trying things and then refining as I learn, but that depends a great deal on what the item is. In this case, I don't want to slap something together (like one of those coffee can contraptions or a some heavy firebricks held together with angle iron) to realize a few weeks later I'm wasting my gas just getting the thing to temp (if it even will get to temp) and have to build another one.

Um, did you watch the video? The very first thing he presses is a 1 1/2" diameter by about 6" long chunk of steel, end wise and turned it into a puck about 2" thick on flat dies. The second thing was a leaf spring, looked like 3/8 thick, and he pressed a tang on the end of it pretty quick. The third item was a 1 1/4 x 1/2 bar using a 5/8 bar as a kiss block to dimension the piece. He dimensioned about a foot and half of it in less than 2 minutes. I don't want to be argumentative, but a couple folks keep insisting this won't work. Here is a video showing the guy doing the conversion with the details and showing it in operation on three different dimensions of steel doing three different types of operations. If you still feel it won't work, then please tell me why, not simply that it won't. As far as squishing 2 x 2 1/2, that would be a damascus billet, obviously I'm not looking to mash it from 2 1/2" thick to knife thickness in a single press.

Pinto blades, something else to consider, "value" on imported assault style firearm is a crap shoot in the long run, you're relying on political whim. It might be valuable right now because of the ban, but what happens when that ban expires (if it does) or gets overturned? I've been down that road in years past, even so far as losing a Russian made AK because the ATF forced a recall on a certain batch claiming they were "too easy to make fully auto." I've forgotten the exact details and the letter from the ATF is packed away somewhere. The importer promised over a period of several years that I'd get a refund or a new rifle...I never got either, but the point is, even the Clinton "assault rifle ban" expired and all of those pricey pre-ban parts suddenly got cheap again. I guess what I'm saying is, keeping the firearms is gambling the value will hold on them, the anvil isn't a gamble (although as Buzzkill mentions, the asking price is on the upper end)...but, it'll be in your shop for as long as you ever want it. Personal opinion, I'd try to negotiate the deal for the other rifle and not think twice about it.

How so?

Nah, I'm gonna wait. If I start picking up pieces and parts, then I'm going to want to start putting it together, and if I do that, then I won't be able to wait to get the rest, and...just gonna wait. besides, I have a lot of reading and studying to do on forge designs, building techniques, burners, materials, etc before I start acquiring parts for one. I really want this to be a one-time build and get it (mostly) right, at least for a first forge. Call it a personality quirk, but I really don't cherish the idea of messing with kaowool and refractory mixes. I despise concrete work or anything remotely resembling it and to me, this does.

Watching and learning what I can about forging a blade, I see that smiths always form the tip on the blade by banging the steel back into itself at the corners, then flatten, repeat until it is the desired shape. I imagine that one could simply grind or cut the tip to shape like in a stock removal method. My question is: does the forging process provide some structural benefit to the steel or is it simply a matter of time savings?

Medical grade super glue (n-butyl cyanoacrylate ) makes for a fairly durable and shiny finish on wood and would be food safe. You can polish it glass shiny. I've used it in the past on wood pens I made on my lathe, and after years of use, it holds up. It will fracture though if you drop it. n-butyl cyanoacrylate is pricey compared to the super glue you buy at the hardware store (methyl 2-cyanoacrylate and ethyl-2-cyanoacrylate). There is lots of discussions about the generic type being food safe after curing, but easy enough to err on the side of caution.

Frosty, exactly. Your idea of remotely mounting the engine is certainly an option. Of course, along with selling the wheels/tires, trailer hitch, selling that engine too, you could recoup a decent little chunk of change to reduce purchase cost of the splitter. Rebuilding cylinders too, it really all depends on what and how much work you want to put into it. You could source every part used and hit the scrap yard to get the steel for the beam, build your own totally from scratch (and I know a few machinists who would consider the idea of building a cylinder from scratch as a weekend challenge). I think jbradshaw above sort of hit the nail on the head with his question concerning travel speed. Even looking at commercial forging presses, I don't see a lot of information of ram travel speeds. You are so right about it too, obviously, you don't fully cycle the ram for every press, just move it somewhere slightly above the work to reposition and then press again. Concerning a kinetic splitter...that ain't a press, that's a horizontal power hammer! :-) If travel speed on a log splitter is really THAT much of a concern, it's not difficult to change that. Get a higher flowing pump or even a regenerating valve. Obviously, a 2-stage pump is key, need to generate the pressure without massive power input that a single stage would require. I did see a video of a guy who built a 60-ton press using two 30-ton rams. I imagine he might have a specific use for that kind of pressure working massive pieces of steel, but that's just crazy for the average home shop hobbiest. I can just see that "Yes, we make your damascus knife from billet to ready to heat treat...all in one press cycle!"

North State, I'm loving this thread. I'm even more of noobie than you are as I haven't even begun to build a forge yet (target date is next spring). Referencing back to an early part of this thread, specifically on the "phobic" vs "philic" discussion, one of my high school teachers put it this way: "Phobic" is like any other "phobe" as "phobes" aren't "for" anything. "Philic", on the other hand, while not a complete acronym, the "ILI" can be thought of in terms of "I Like It." We had one fella that confused "philic" with another word (replace the first "i" with "a" and add an extra "l") and well, a certain degree of teenage boy humor ensued. The explanation and the word confusion has always made that stick with me. Good times.

Oops, sorry about the commercial link. To see the splitter I mentioned,

Yes, the smell is pretty horrendous. I haven't tried muriatic on files, but I guess it's the same process, just faster. Even with the vinegar, I have a bucket with a solution of water and baking soda to dunk them in, then dry with a rag and then a hair dryer followed by a good dousing in WD40. If the parts are chrome plated, like sockets or wrenches, I like to use car paste wax on them. My barn isn't heated so tends to get pretty humid. I've found the automotive wax does a really good job keeping the rust away. I use T-9 Boeshield on cast iron and metal woodworking tools, table saw surface, drill press platens, lathe, etc as it doesn't contain any silicones or teflons and won't ruin wood for finishing. It's just a bit pricey so I use the automotive wax an tools and metal that aren't used for the woodworking. I also use a brass brush when cleaning the parts from the vinegar and it frequently leaves a thin goldish finish. I wonder if that minuscule amount of brass all over the part has any rust inhibiting properties? I might try a little test just for S&Gs. I'm guessing it probably won't, but I have nothing to lose by testing it.

Here's a splitter I've considered as a viable conversion candidate: commercial link removed I picked this one primarily because it specs a pretty fast 9.7 second cycle time (pump is 2-stage 14GPM). However, it does also state that it is "auto return", so it might entail a replacement control valve for press operation (unless the auto return function is actuated by a spring or some simple mechanical means that could be eliminated). Also must consider an electric motor to replace the gas engine (unless you really want to run your press on a gas engine). I think a 3HP TEFC motor would run it adequately, or a 5HP motor would do so without question. Replacing a gas engine with an electric is not a 1:1 requirement for HP (google it to understand why). Of note though, concerning the pump, most of them, at least in the sizes we're talking here, are flow rated at 3600 RPM. Most lower priced TEFC motors (i.e. sub-$200 range) are rated at either 1725 or 3450 RPM, so with the 3450 motor you are losing 150 RPM to the pump. I don't know precisely how much that lower RPM will affect flow rate as you have a large and small displacement pump in a 2-stage pump. The given flow rate is typically given when both pumps operate to give you the faster no load speed and then kicks over to the small displacement pump only to get the high force output (and obviously, travel speed slows way down at that point). Without calculations or knowing more specifics on the pump in this application, I'd say the difference isn't significant. If you really want exactly 3600 RPM fro your motor, you can get different RPM speeds in TEFC motors, but from what I've seen, anything other than 1725 or 3450 is pricey, at least twice the price or more. There is also the option of pulleys and ratios if you really want to go down that route. With all that considered, the question is one of economics. Would it be cheaper to buy a pump, motor, cylinder, control valve, filter, hoses, fittings, all the steel, etc and just scratch build it? I think that'd end up a bit on the more expensive side, even using cheaply priced parts. For example, a 2-stage 16GPM (2 more GPM translates into slightly faster cycle time) pump can be had for $129.99 new. A 4" x 24" log splitter cylinder runs in the $225-$250 range (or opt for a shorter stroke cylinder...do you really need a 24" stroke?), a 4-way, 3 position hydraulic control valve that can handle up to 25GPM is around $125. There's still the question of the electric motor, and all the steel to build the beam, ways, ram, fluid tank, filter, hoses, etc. I think the scratch build ends up costing more. Even if you have to replace the control valve on the log splitter, you still end up ahead buying the splitter and converting it. Also, you can re-purpose or sell parts you remove, like the 16" DOT approved road wheels and tires, the control valve (if it gets replaced) and even the trailer hitch. Not a significant recovery of money, but just those three things alone would potentially net you a $150ish in the want ads, which would cover the cost of the control valve replacement if needed. Anyway, you get the idea. For the cheapest route, then certainly find everything used, but you'd have to find the right deal. In my area, just searching local want ads and craigslist over a period of time there are no good deals to be had. What I would consider viable used units, the sellers want new or near new prices. Even beat to death units they want more than half the price of a new one. There are a few "custom built" ones (i.e.home made) that look like they wouldn't crush a beer can, much less put out any tonnage of pressing pressure, and the sellers think these things are gold plated. For me, at least, it seems a new unit, such as the one I linked above, is the route I'm going to have to take. Even buying a brand new splitter, any necessary ancillary or replacement parts, and converting it would still give you, in my opinion, a more than adequately functional press for a lot less than commercially made "forging presses." After all, there are literally hundreds, if not thousands of videos of people doing this type of press. If it didn't work well, or was more trouble than it was worth, then that many people wouldn't be doing it. Then, there are those that will insist only a proper commercial press is worth owning and using....

Thanks arftist, I've read discussions elsewhere that squishing damascus in a press to set the initial weld is bad. I've also watched plenty of videos of smiths using a hammer to smooth/flatten a knife after it's been forged to shape and it seems this saves a lot of post heat treat grinding to final shape. There's no hurry on this at all, just thinking about things and learning more about hammer types/styles and so on. I'm not 100% committed to the idea of building a hammer at this point. As for the press, I'm curious as to why you say I'm way off on my idea? Here's a video of a channel I watch. He converted a splitter that ran on a 5.5HP Honda engine with a 3HP electric motor. Are the ram speeds on this conversion too slow? Looks to me like it works pretty good, but I'm always open to learning.

Agreed, a releasable magnet would be more convenient and ways would be more solid for alignment. I'm sure such a set up is possible with some tinkering, but I just wanted to show the simple operation for this type of chuck for knife grinding vs a regular type of surface grinder. I've done some reading and watched some videos on making releasable magnet chucks, it's fairly complex for a mechanical release (at least way more complex than I expected it to be), unless you want to try your hand at an electromagnet.

What sorts of usage are you looking for? Do you intend to use it for knives, or generic smoothing/flattening of pieces? What capacity of work piece size? I ask because there quite a few slick designs as grinder attachments on youtube. Your intended use will dictate a couple things. A "regular" surface grinder (the hard grinding wheel with a magnetic chuck and a cross-slide vice) is designed to make incredibly flat surfaces, but it won't help you do things like distal tapers unless you fuss with setting up the piece with parallels and shimming the piece, etc (and they aren't cheap machines). It's really designed to create super precise work. A belt grinder type "surface grinder" can achieve better flattening results that you can by hand, but won't be anywhere near as precise as the above grinder, but that's not necessarily a bad thing. Some designs are particularly useful for knife making as they can be adjusted quickly and easily to grind in distal tapers, or tapering tangs, etc. Instead of a large, permanently mounted magnetic chuck, they use a simpler magnetic chuck (thinner in width, and smaller in general) and a swing arm design to change cutting depth. In use, you manually slide the chuck forward and backward under the wheel (there is no side movement like with a cross-slide vice). Since it is used with a contact wheel, with the hinge point of the swing arm behind the wheel, you maintain flat cutting as the depth change is just a tangent on the wheel. The front edge of the chuck is adjustable up and down to allow for tapering grinds. As I said, useful for making knives to get the majority of the shaping done with final finish coming from hand sanding. You could also make one with the cross-slide type magnetic chuck like a regular surface grinder strictly for smoothing, flattening, and final finish of a piece, which they will do an amazing job (much much better than by hand), but without the increased adjustability like I described above nor the hefty price of a regular surface grinder. Here a video of a knife type grinder that I mention. It has the front adjustment for the distal tapering:

Ah, Jeremy's grinder is the one I'm planning to build as well. There are quite a few videos on youtube of folks who have built it and all seem to have gotten it done quite well. Of course, some folks have also changed the design to some degree, such as using heavy wall square tube instead of fabricating the the tubes from 3/8 stock like Jeremy did. I also plan to make some changes to the design, specifically I want to see about changing the dimensions enough to fit a 12" contact wheel, or possibly even a 14". Looking at the design, I believe this is possible without losing any rigidity (I mean, the thing is made entirely of 3/8 stock, it's a tank!). I'll probably mock up my version out of cardboard or something suitable just to ensure the measurements or what I may need to change (I don't have a fancy CAD/CAM program and no real skill with them even if I did). If such a change becomes unwieldy, then I'll just build as designed and not worry about it. A different approach would be to skip the tensioning wheel and route the belt to a 2-wheel set up for the larger contact wheel. This would provide a few more inches of belt length to extend the tool arm to clear a larger wheel without the need to shorten the holder tube, but that would require some method of tracking adjustment via the contact wheel, which may not be optimal (I've seen 2-wheel grinders, so a little research into how they operate is warranted). I'd also like to have a go at making a rotary platen for it as I'm quite fond of convex grinds for sharpening, especially the kitchen knives. It seems to provide a great balance between cutting and longevity to the edge. Straight up slack belting though makes it difficult to control as the belt is a bit too sloppy. A rotary platen would be awesome for that. I don't know that I would call the build particularly complex, it's pretty straight forward and Jeremy designed it to be that way. Besides, as he says, "If you can't make it precise, at least make it adjustable" and I think he's done a fabulous job in that respect. The key to the tube clearances is the method he uses to make them with the shim pieces. You do still run the chance of warping the tube in final welding, or shrinking the fit too much, but if you've watched the video, he changes his shims from two layers of soda can material to utility knife blades which added some more clearance. If you have experience sticking metal together with a welder and have the patience, I think anyone willing to take it carefully could build one of these easy enough. The "hardest" part of the build, to me, is all the cutting of 3/8 material, that's a test of patience in time and effort (especially if you don't have a bandsaw). As with any metal contraption, the key is straight and square and if you aren't sure how to achieve that, there are tons of videos with tips and tricks on how to do it, usually quite simply. Anyway, that's my $0.02 worth. Building a tool or machine there is always the chance of issues or outright failure, but that's part of the fun and learning. :-)

The log splitter I have in mind runs on a 5HP gas engine, has a 2-stage pump and a 9.5 second cycle time (that's full travel of the ram down and back up). A 3HP single-phase 220v TEFC motor ($189) will operate it quite nicely (many such conversions on youtube of this set up and they function well). I could spend $229 on a 5HP TEFC motor if I think I need the extra HP. I could even possibly source a used motor even cheaper. I understand about the billet size, but with damascus, since it typically requires a lot of heats, cutting, stacking, reheats, you typically lose a lot of material and end up with a fair amount less at the end. I am OK with the hammer being slow initially. My main interest is in setting the weld, doing much of the drawing and squishing with the press then return to the hammer, theoretically with a lot less billet mass at that point, to do final shaping/finishing/planishing. That seems to be the basic sequence makers use when they have both tools. Fluid drive sounds complicated and expensive? Based on what I've seen, I'm guessing it's going to have to be something mechanical, although admittedly that air cylinder hammer I saw on youtube is intriguing. It's very compact, and looks like it hits plenty hard. I'm just not convinced the cylinder is going to take the pounding over a long period of time (they are cheap though, $60 for a 2.5" bore, 20" stroke cylinder that specs at 280Kgf (617lbs) of force and a max air input of 145 PSI. Here's the link to the video I saw on youtube: https://www.youtube.com/watch?v=hfJFDZTZTqc Unless there's some specific type of steel for the anvil, my understanding is that it needs to be at least 10 times the mass/weight of the hammer, does that sound right?

Old thread, but found this interesting as I just took the last few rusty tools out of my container of vinegar just yesterday. It does a a great job on light rust, but isn't so great on heavy rust. The problem is that it attacks the parent metal as well, so you have to be careful with certain tools as you don't want dimensions reduced. I find that for heavier rust removal, electrolysis is a better solution. I didn't see it mentioned (maybe I missed it), but one really good use for vinegar is "sharpening" files. Take an old file that doesn't seem to be cutting well anymore, or buy up all those clapped out looking ones at yard sales for cheap and drop them in vinegar for a day or two, wire brush them and in many cases they cut like new!

Press will be a converted log splitter. Been looking at used ones in the various local for sale ads and Craigslist and man, people want new or near new prices for well used ones and ridiculous prices for those that are clearly clapped out. I'll probably go with a new budget one in the 22-25 ton range (I found a brand new 25-ton unit for $899). I'm mainly after the hydraulics and the steel beam/bed. Of course, the gas engine will get replaced with an electric motor. I first thought of just buying a pump, cylinder, etc and build from that, but dang, just a proper 2-stage pump with enough flow rate is nearly half the price of an entire new log splitter, so a conversion is the plan. Anyway, my question was really about a power hammer. I know how it goes with the power tools, bigger is always better, but perhaps not so much in this case. Like I said, I don't want something so big and massive that I shake the surrounding country side like that Pilkington Alec Steele has. I guess the best "requirement" that I could give is it needs enough oomph to set the weld on a decent sized damascus stack (say, 2" W x 2.5" thick x 5-6" long) and then perform the usual drawing, shaping and flattening on a piece that size. I'm curious about the style of hammer that ya'll think works best for that sort of work. I don't really have any sort of space requirement (I have a 10,000ish sq foot barn). I guess I shouldn't have said "simpler to build" as complexity is not really a concern.

If you were to build your own hammer, which mechanism or style of hammer would you choose to build? Which type mechanism lends itself better to damascus/knife making? I've seen everything from air hammers (like the anyang 33lb), even home made ones made with an air cylinder powered by a compressor to slam the hammer down (it was quite compact and powerful), to what I assume is called a "tire" hammer with tire spinning an offset cam connected to the hammer via connecting rods with a spring of some sort between them, to longitudenally mounted leaf springs that rock front to rear. I'm sure there are other mechanisms I'm not even familiar with. Which type do you think is simpler to build, but provides the best combination of power and operability for a small home shop? I guess one last qualifier is something I won't need to cut into the foundation and build some massive isolation block to use. A log splitter press is on the list too, and I realize this can make up for some lack of hammering power, but I'd like the hammer to do some of the work, it seems to leave a much flatter and consistent finish (planishing?) and a press isn't always the best for making damascus, at least for initial welding.

First post here and I do come with a specific question I'll post in the proper forum. Other than welding and very basic fabrication, I have pretty much no experience in metal working. I have been wood working on and off over the last 25 years, but I am interested in learning knife making and building some of my own shop tools (2x72 grinder, hydraulic press, and maybe a small power hammer, that sort of thing). Right now I'm more in a "book learning" mode as I'm not quite ready to start gathering parts and pieces to build anything just yet. I've learned a bit about metallurgy of carbon steels (pearlite BCC to austenite FCC structures and how quenching quickly to below the eutectic temperature creates martensite), damascus techniques, etc, etc, etc. I've also watched quite a bit of youtube videos on all the knife making stuff, building machines, forges, tools, and so on. Hoping to get a very basic (i.e. forge, anvil, tongs and hammers) set up running next spring. I already have a very small 1x30 belt grinder that I can practice with while I build a 2x72 grinder (using Jeremy Schmidt's design for those that know it). Anyway, I'll definitely be doing a lot of reading here and will probably pester the heck out of everyone with a million questions :-)