Hydraulic Press as Power hammer for Armor Making

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I was wondering if I use a hydraulic press for plate armor will it give the same effect as a hammer and stake or will it stretch and thin the metal?

Interesting question.
I have only worked a little with a hydraulic press but will pass on what I know.
It should work fairly well for simple dished forms. So this is changing flat sheet into bowl shapes. You will have to be careful of wrinkles developing in the steel sheet. If a wrinkle starts immediately press it out or it will get out of control. Hydraulic press have the advantage of being very slow so you can see things develop. The extra pressure means that once an unwanted shape starts to develop it needs to be corrected right away.

The hydraulic press wont work well when using a raising technique on the sheet steel. You may have to do this by hand on a stake as usual. The raising techniques involve closing a piece of sheet over a form or stake with very light repetitive hammer blows. This is actually thickening the steel as the pipe or cone is created. The press tends to deform the steel either by thinning if it is trapped between two dies or by depressing it into open space between two dies. A lot will depend on the types of dies that you make for the press.

For simple armor forming I would think about a mushroom shaped top die and a matching bottom die that could be made from heavy pipe with 1/2 inch round bar welded around the top edge to provide a round surface of contact. The diameter of pipe I would try would be about 3 inch but this would vary depending on the work you were doing.
You will have to experiment here.

Like power hammers any dies that you make should have the edges well radiused so the edges of the dies do not cut into the steel. This will give a smooth transition to overlapping pressings.

Hydraulic Press as Power Hammers.
A hydraulic press is very different from a hammer and does have a different action. They will do some of the same things. Other things not as well. Advantages of the press is the tremendous force that is developed and there is no pounding so they are relatively quite. This can be important in a residential neighborhood. The main disadvantage is that the presses are slow.

You can work hot metal under them and many people use them to develop mosaic damascus with the controlled pressure. The press will work for drawing out but not as fast as an air or mechanical hammer. The press will work very well for punching holes or shearing (splitting) or for decorative veining or punching. All can be done hot provided your dies are set up for it.

Of course a press will work very well for flattening or controlled repetitive shaping if the the dies are exactly made for a specific purpose. Hydraulic presses also have a relatively small footprint in the shop.

In general I would say a hydraulic press is a useful addition to a blacksmith shop but it will mostly depend on the type of work that you are doing. For the armor it may work very well but you will have to experiment with die shape and size to make it work effectively for you.

Sample Hydraulic Presses

Hope this helps.
David

Knife Making Belt Grinders

Recently I have had many inquiries about knife making and belt grinders.

Knife making is one of the most interesting parts of blacksmithing and is actually how my interest was peaked. Had I had a knife making belt grinder when I started it would have been so much easier.

In general there are four different steps in blade making.

1. Forging the blade from the original bar. This is where the rough shape is created. You may have heard the old saying 5 minutes at the forge saves half an hour grinding. For me that certainly is about right.
   
   
2. Primary and secondary grinding of the blade. This is creating the finished shape of the blade through a series of grinding and sanding steps. For me this takes the longest time and is the most exacting.
   
   
3. Heat Treating. This is the hardening and tempering of the blade.
   
   
4. Final sanding and polishing. This is when the blade is actually sanded to a perfect finish. You may choose to buff to a mirror finish as well.

So a lot of questions have come from people just starting out in blade making. They are wondering about the grinding steps.

Belt grinders are the best solution for blade making. They give you a flat surface to work on and remove material quickly with coarse grit. Fine grit can leave a satin finish to shiny if you go super fine.

The problem is that knife making belt grinders usually range in price from $1200.00 to $2500.00. Now that is a lot of money if you are just trying this out as a hobby. If you are committed then I would suggest looking at this price range. The standard in knife making is the 2 inch by 72 in belt grinder with usually a 1 hp or 2 hp motor.

Back when I needed a knife making belt grinder I couldn't afford to pay the $1000.00 plus for a factory built one, so I choose to build my own. So on a shoe string budget I built one. Does it work? Yes fairly well. There are things I should change on it, but in general I am satisfied with the finished piece. I used no plans and scrounged as much as I could.

I recently found good plans for a nice belt sander that requires no welding. It all bolts together!

Just Click on the above image to be taken to more information.

These plans provide simple construction just with cutting and drilling and bolting everything together. Of course you could weld the joints that needed welding, if you had a welder. It would only make it better.

Now you will have to recognize that some of the parts are expensive. Motors and contact wheels do start to add up, but this is the cheapest way to build a good quality grinder.

I also found this tool


This is very similar to a belt grinder that I started with before I built my big one. If you want to try knife making as a hobby and are on a tight budget this sander will work.

Now this is a light tool that bogs down if you are really trying to hog metal off and the small belts ( 2 inch by 27 inch) wear out quickly, but it will work. This one has 1/2 HP motor. The belts are pretty economical and this is a good way to see if you like knife making.

If you do like knife making and knife grinding then you will probably want to upgrade fairly quickly.



Now I did come across this machine and WOW! This is an industrial metal belt grinder. It sells for only $695.00 and has a 4 HP motor. This is twice the power of the best knife grinders at a 1/3 the price. It is solid and versatile. It uses a large 3 inch by 79 inch belt and has both contact wheel and flat platten for smooth grinding. Had I come across this knife grinder years ago I would have bought it.

There is a downside to it. This is 220 volt, 3 phase. Now 220 volt may not be a huge problem as most shops with serious equipment have 220 volts. 3 phase is usually limited to industrial areas. So now you would have the choice of replacing the motor, or buying a phase converter.

Both are about the same price. The phase converter for this belt grinder is recommended as
So we get back to about the $1000.00 mark but with a 4 HP motor to chew through the metal.

From everything that I have looked at, this is the most cost effective knife making belt grinder on the market. So I hope I have given you some options to look at if you are starting out in knife making or if you are looking to up grade to an industrial level.

Oh yes the most recent blacksmithing course I taught, the students were interested in making a knife as their Sunday afternoon project. They did quite well. I will put up a picture of mine when I get it finished. I still have some grinding left to do.

David Robertson
Artist Blacksmith

Blacksmithing : Forge Welding Cable Damascus

I' m interested in trying the steel cable damascus knife, any advice?

Cable is actually really nice stuff to weld. There are a couple of tricks that people forget that help a lot.
The alloy in the cable has a good success of welding even at fairly low temperatures. Having said that use a full welding heat until you are comfortable with it.

Crane cable is better than elevator cable. Elevator cable has an inner core twisted one direction and an out sleeve twisted the other direction. This is called counter rotating cable. That is the cable doesn't twist as it spools off the drum.

Regular crane cable has inner and outer strand twisting in the same direction.

What this means and this is the important step, when you first heat the cable up, clamp it in the vise and twist it as tight as you can get without it buckling. This helps close up the air spaces for better weld. The elevator cable won't twist tight as the inside is expanding when the outer sleeve is being twisted tight, causing spaces to open up.

Back into the fire and take up to a nice orange.
Gently wire brush it, and add flux.
Back into the forge to take the welding heat.

The next trick is instead of welding flat on the anvil (although this does work) use a U shaped bottom swage tool or swage block to help support the sides of the cable when you weld.

As you make the actual forge weld rotate the cable with the direction of the strands. That is each hammer stroke is actually tightening the twist.

You will find that once the cable strands are weld the feeling of the metal changes from the floppy cable to a hard bar. Once it is well stuck together as a bar take a series of refining welds on all edges to make sure any loose strands are tacked down.

When you are completely satisfied that it is well welded then stretch out as normal and make your knife etc. as usual. Once completed, ground, hardened, then sanded again then you can etch in acid to reveal the pattern. You can use vinegar warmed up on the stove. Takes along time but will give you a bit of the pattern, and is the safest acid.

I use more aggressive acids such as sulfuric or nitric or some times ferric chloride. Follow all acid precautions with these strong acids.

Neutralize and take a look at your knife.

David Robertson
Artist Blacksmith

What is The Best Steel for Making a Blacksmithing Slitting Chisel From?

What is a Slitting Chisel and What Steel Should I use For it?

A slitting chisel is a very thin flat chisel used for opening or splitting steel when it is hot. The steel has to be very resistant to heat so that it doesn't deform as it is hammered through the steel.

Most slitting chisels are about 1 inch wide and the edge less than 1/8th of an inch thick. If you are planning on making curved cuts consider making a slitting chisel about 1/2 inch wide. (The smaller the width the tighter the curve you can make!)

I usually try to make the chisel about 8 to 10 inches long. My preference for making this tool is H13 steel or S7 steel. Both of these steels are heat resistant and stand up to the heavy abuse. They are a bit difficult to forge down to size but it is worth the effort as they last much longer than other steels.

I have used coil truck spring. This is an alternative and will do in a pinch but this steel is not very heat resistant. This means that you can't work it down so thin and if you let it show a bit of color as you are hammering through the edge will deform. Then if your chisel doesn't get stuck you have to sharpen it. As I said it will work but not as well.

I have had good luck using old jack hammer bits which I believe are S5. They stand up to both the heat and the hammering.

Good luck making your chisel and it doesn't hurt to have 3 different sizes. 1 inch , 1/2 and 1/4 inch for detail work.

David Robertson
Artist Blacksmith.

Blacksmithing | Can a File Make a Good Knife?

How to Make a Knife From a File?

I have a bunch of old and fairly new files of all sizes. I would like some information on the proper procedure in turning them into a decent blades.

Hi
Files can make decent knives but you have to do a fair bit of preparation first. To truly make a good knife I would suggest grinding all the teeth off so you are down to bare metal. If you forge the blade and the tang leaving the teeth on. All the valleys at the bottom of the teeth make small creases in the surface of the blade.

When you heat treat the blade these creases can form cracks or potential cracks, and are always a point of weakness.

In general file steel can be an unknown tool steel and I have heard there is considerable variation in quality. I would try quenching in oil for most. I would actually recommend buy new steel. O1 drill rod is easy to get and makes a good knife and most importantly you know what you are getting. Buy 3/4 or 1 inch round and just forge it flat then make your knife from that.

It might seem a little expensive to spend $30 or $40 on a piece of steel 3 feet long. If your knife breaks in the final heat treating after spending 10 to 20 hours on it the $10 spent on the piece of O1 used for the other knife seems pretty cheap.

If you are stuck for finding O1 and tool steel in your area try clicking through to Onlinemetals.com They carry a full range or sizes.

I have had a number of knife making requests lately so I am planning on doing a newsletter series on it in the near future.

I hope this helps.
David Robertson
Artist Blacksmith

How to Deaden The Noise of an Anvil ?

How Do I Decrease the Ring of My Anvil?

Hi
There are a couple of tricks to deaden the noise of an anvil a bit.

I do use a chain but the secret here is that it is a fairly heavy chain and you wrap it around the anvils waist. Then it must be bolted down very tightly to the stump or stand that supports the anvil. This does help deaden the ring significantly. The idea is to tightly clamp the anvil to its base with the chain.


You can also add a good sized magnet under the horn or the tail of the anvil. This will collect scale but it helps remove some of the ring as well.

Another option that I don't like as well as the others is to take a short length of chain and make a loop out of it and hang a weight off it. Then place the loop over the horn or the tail of the anvil. It too will help deaden it down the noise a bit, but as soon as you need that spot on the anvil it is in the way and has to be moved.

Hope this helps.

David Robertson
Artist Blacksmith

How to Avoid Distortion Heat Treating Damascus

How Do I prevent Scale Build up When Heat Treating a Knife?

Well making my third Damascus knife 13 layers ,when i get it polished and to the point of tempering when i put it in the gas kiln red hot to loose magnetic it warped every which way .made out of all the same coil spring steel and hammer welded plus all sorts of slag all over it now so while it was red hot gently hammered it straight again and annealed . so how can i get it polished perfect and temper with out slag and distortion next time now after i sand and polish it again ? whats to keep it from happening the next time I go to temper it ???

Hi
This is a little tricky to answer as I have not seen all the steps that you have gone through.
Slow cooling (annealing) in vermiculite or wood ash to relieve the stresses is very important. This should remove much of the tension between the two different types of steel. This should help reduce the warpage when you heat for quenching.

If you are heating the blade in a gas forge hold it so that the back is up and it heats evenly from both sides this should help with the distortion as well. It should only be heated just past the magnetic point. It doesn't have to get super hot. Then pull the blade out and test with a magnet until it just pulls then quench the whole thing in the appropriated quench medium. Water or oil. Then temper evenly 425 degrees in a toaster oven. Then a quick sanding and hold the edge in a water bath (about 1/4 inch deep) and paint the temper colors on the back with a torch. Blue on the back straw on the edge.

Then sand to final finish always keeping the edge and the blade cold by dipping in water.

In short I rough grind and sand to about 80 grit before I heat treat. The final sanding is done after the blade is hardened. When I harden there will be some scale formation but it is really very little as it is only up to color for about a minute and not very hot. Just enough to lose the magnetism.

I know some people use a nickel foil to wrap around their blades so that it doesn't oxidize very much. I have not used this technique but understand it works well. You would have to source a knifemaking supplier for the nickel foil.

Hope this helps.

David Robertson
Artist Blacksmith