Kozzy

Always think of brazing as gluing--that is, you need some sort of proper structural joint to the first place. A simple butt joint might "glue" but it will be weak and a poor substitute for a properly overlapped brazed joint. Welding on the other hand will end up stronger than the parent material if done properly. Lots more heat input to screw the product up though. In any case, turn this around to be opportunity rather than scrambling to fix a shortcoming. Can you do a split piece overlapping the blade which becomes part of/enhances the design for instance? A strongback on the blade that transitions to a tang which enhances the design? A bolster/tang set-up that overlaps the butt end of the blade and adds to the visual appeal? Think about it for a while and you might be able to come up with a solution that is actually a design improvement. Most of those would work with even a brass brazing rod, cleaned up, showing a little golden color at the joint. There are similar inexpensive brazing rods that have a high zinc content which remain "silver" colored and have a high tensile. I just checked mine and they run 70,000 psi. Talk to the actual guy at the counter of a true welding supply house (every town has em). They'll have suggestion on the best rod...and often sell a stick at a time.

The issue is the amount of fuel needed to bring a material up to pouring temp. As the pouring temp goes higher, losses from the furnace also increase dramatically (and not in a linear fashion) so doing the higher temp stuff requires a LOT more fuel than lower temp stuff. It usually becomes inefficient and costly to do something like steel except on a lark. Brass is probably the highest pouring temp material that might be in the realm of practical for a home-brew system. Just because it's possible doesn't make it practical.

Hey John--What are the adjustable trammel points shown in the photo of the press laying on it's back used for? I don't recognize that feature.

Calculations on the structure of a C frame press are seriously complicated as people have said. You are not just dealing with material strength but you have to deal with deflections and deflection is not linear, it's exponential. Twice the distance, 4 times the deflection to worry about while "strength" remains linear to fool the calculator. It becomes a dance between strength and deflection to get it right. The dance can be so complicated without software evaluation solutions that most people simply grossly over-build. We have a 100 ton ship built C frame hydraulic in the shop and it is a monster-- multiple 1-1/4" thick solid side plates of some very expensive certified material. Makes a hell of a noise when punching holes in thick stuff and the whole world shakes when the slug breaks free.

I did some quick poking around and it looks like SOP for leather stamps is magnesium with hardened steel being the "upgraded" custom model. However, it also appears that the custom stamp industry is now doing them by laser cutting so it's a lot cheaper to get a custom stamp made than it used to be. Might be something to look into. Are you doing one special stamp or thinking about using a variety of the decorative stamps that are available for leather to impress patterns? I have seen hardened steel stamps to do bits and pieces of more complex shapes...small teardrops for instance that can be stamped several times over radially to make flowers. The "segments" option might be good if what you want to stamp is complex--and partial segments might also be pretty easy to file in a roll-you-own stamp.

ThomasPowers was right in his warnings. I guess I should have made that clearer myself. I assumed that this was mostly academic regarding learning what process and materials were available so threw out some stuff to learn about---but would never recommend making a product of any kind that (ever!) that was relied upon as a safety measure to mitigate risk of injury.

There is a way to look in for cracks and defects---look up mangaflux. Not something sitting on everyone's shelf but definitely common in the metalworking industry. The actual magnaflux site seems to be overwhelming but they also have products that are not complicated or horribly expensive. They are not the only brand.

Ductility and cold forming is one of those subjects where voodoo is involved. There are so many factors involved that it's hard to give a reasonable answer to any specific situation. For example, in the press-forming industry of sheet metal, some items take a dozen or more pressings to get to the final shape using progressive dies: Intermediate shapes are chosen very specifically to work through the process and prevent cracking (assuming cold work from start to finish). Speed of the press also greatly affects outcome--some items like fast and some like slow. Great planning goes into the process to decide where the material will and can be thinned or compressed when designing the product. In terms of armor, think about something like a motorcycle gas tank--custom tanks are often formed on a lead bag by hammering or power planishing hammer with the addition of a shrinker and an english wheel to smooth and stretch the material in a slow and controlled way while cold to some fairly drastic shape changes. How far you can push it is a mix of material, voodoo, experience, skill, and plain old dumb luck.

If you happen to own or be tight with a business in some areas of the USA, fire extinguishers might be basically "free". Many big cities require commercial businesses to either replace extinguishers after 5 years or pay a LOT for a commercial service to re-certify them. It's actually cheaper to just go to Costco and buy new ones if your business isn't very large. They're still good for many years but it's part of the hoops a business has to jump through. The old ones have to go away and they'll generally be just fine for a home situation, especially if you can get enough to be redundant. I checked and most of the extinguishers one would want for a forge situation can tolerate freezing weather just fine also.

Theoretically you don't need flow, just a single line for steam to escape and make-up water to enter that is above the level of the nose/exposed part of the tuyere tube. Not the way I'd personally do it but as long as pressure never builds up the internal temp is going to hover around the boiling point of water.

Thanks for more than you think. The US site had air knife systems in addition to blowers and for work I was just designing a piece of equipment that needed one--was about to do a web search to find a supplier

Well, I personally swear by Klingspor abrasives but the prices in your site look pretty tempting for some things. If I weren't such a lazy bum I'd do a side by side comparison to see.

I like it--a LOT. I could easily talk my wife into sponsoring something like that as long as I put a grate somewhere and told her it was a BBQ for her. Can you toss out a little info on the blower you chose? Source for that one? I've been poking around regarding blowers and haven't seen that one pop up in searches.

I took a look and those prices seem a little too good. Chinese imports? Looks like your best bet is to order a couple to test and let us know

Late to the party as usual Pexto has a really spiffy tinsmith bench and stake system that the anvil shown probably came from. Lots of great pieces for it and a great toy to add to the shop. I didn't jump on a full set-up here last year that was $ 200 bucks and I've been kicking myself ever since. (do an image search for "pexto tinsmith's anvil" or bench for lots more photos and more pieces.) Now that you have one piece, you get the fun of searching for more in your travels.

Welcome and thanks-- Seeing you were in Scotland got me poking around the "internets" to see what those sock knives were called and what they were generally designed to look like. I highly suggest anyone interested in knife-making do an image search on "sgian dubh". There are some beautiful examples to look at and it's not a particularly complex form or size for a beginning knife maker to try.

I think this might make the assumption that the concrete is decent quality stuff--which might not be the case. I have to assume that an old railroad depot could vary from far over built to some pretty slipshod and questionable concrete back in the day. Although 2' thick implies it was built like a tank, it may still have sub-par compression concrete with little (if any) reinforcing. Older concrete was also often done with beach sand..or whatever sand they could mine locally...often worn rounded sand instead of sharp sand which reduces strength. Similar with whatever gravel was used as the filler. Personally I'd take a close look at the structure and integrity of the existing concrete AND make sure my insurance was paid up. Spread the load, absorb the shock.

Leg vices are not uncommon in your area...just not as common as they tend to be back east. You have to keep your eyes open, visit a lot of "antique" (junk) stores and watch auction listings. For instance last winter there was an auction up near Quincy that had about 8 of them in one shot. You may have to get off the beaten path a little to the smaller surrounding towns and areas. Many farmers have them so watch for farm auctions also. They shouldn't go for big money unless they are the large size and in good condition. Just pass if you find a junker that someone thinks is worth the price of gold. And note that it's not a necessity--just nice to have if you ever run across the right deal. You can make do with even a junker Chinese harbor freight vice until the right leg vice comes along: Probably 9 out of 10 beginning smiths do.

I found one reference that specifies A706W as "low alloy" compared to the 3 other standard grades so I would suspect it to be a poor knife material. However--as others have said you never know until you give it a shot. Make a test knife and if it doesn't work well, "put a groove in it and call it an ashtray" as Bill Cosby said in is 60's routine regarding making stuff in shop class. Found a listing of the constituents including carbon content http://www.portlandbolt.com/technical/specifications/astm-a706/ Carbon max = .3 and carbon equivalent content (weird comparison that's complicated) = max .55

Heat Treaters bible said you did things right...1575 f and oil quench for 4140 so I'd look at aspects of your process---longer soak? Better quench? Temp control? 4340 effectively the same except 1550 f and what appears from the graph to be a MUCH longer soak.

Looking into a crystal ball, the Kinyon seems that it would be easier to modify in the future if one decided to make some changes. Everything is fairly easily adjustable with only minor changes. Tire hammer is definitely better for someone without loads of compressed air and with less amperage to the shop.

$300 would be a very good price around here (like screamin deal) assuming the blower doesn't sound like it is full of rocks. Question for the forge gurus--what was the original purpose of the extra tab and hole at the edge of the casting? Lid of some sort?

When U.S. Steel first started pushing Cor-ten, they advertised that once the initial coating set, it would rust no further. Got their butt sued on that from a NYC project where a skyscraper was clad in the stuff. Like stainless...it stains less--it is not corrosion proof

One danger that people might not know about is the heavy use of dryer sheets in the laundry. They make the surface of cotton (and other?) clothes flammable. What you get is this crawling blue flame--not large and hard to see but it singes along the surface of the clothes. My ex used to love throwing in several dryer sheets for each dryer load-- I noticed it suddenly got warm when welding once so yanked the hat off to see my shirt covered in blue flame. No harm done as it's not an aggressive fire but had I not noticed, it could have been a major problem.

I was the victim of a disappearing post also In a nutshell, bifocals drive me nuts due to head-cocking so I got cheaters with a lower diopter for the magnifying part. That allows a field of view from about 12" to about 4' with reasonable clarity. Not perfect for reading, blurry at distance (but not too blurry) but the best compromise I could come up with. It was that or trifocals. The progressives were awful due to constantly seeking the "sweet spot"