nitewatchman

My R&D Group is developing a new switch point detail and needs a rail bloom to make prototypes. To get this material we ordered probably the biggest knife blank on record today. It is 8" X 10" in cross section and 54 feet long. This would make a lot of blades! nitewatchman

I just realized you were in Italy, ignore what I have said as it applies to the US only. I hate it when this happens.

The Coach Screw Spikes are not ours. They are sold by a domestic company but made in China. The material can be almost anything as long as it passes a tensile test and a bend test. We donot use this source due to the variability of the steel. The chemistry of the steel tin the e-Clips sounds a little low for the carbon. These are correctly called an E-2055 clip and were originally made by Pandrol until their patent expired. They are now widely copied in China and India with varing results.

What you have here are correctly called Coach Screw Spikes and they are intended to attach Tie Plates to Wood Ties. They are usually made from AISI 1045 or AISI 10B22. These were likely made by my company, what is the Head Mark (letters on the heads)? nitewatchman

Unfortunately Rebar is made to a mechanical specification and the chemistry can be almost anything. Chemical copmposition from bar to bar can be very inconsistent. nitewatchman

In my opinion YES.

My company operates two Manganese Steel Foundries producing Railroad Frogs. We have two 10,000 pound furnaces and two 4,000 pound furnace capable of about 3000F. During tapping of the melts we bubble argon through the molten steel to floculate impurities and float them to the surface. These impurities, oxides and dirt are then skimmed off as slag by tilting the ladle and using steel tools shaped like rakes. The steel will indeed coat the rake with a thick coating of metal. Granted due to the nature of Manganese Steel we run very little superheat so the tendency of the manganese steel to melt the rake is reduced unless it is left in the melt for an entended period. The steel coating is NOT fused to the rake and can be knocked off. I supposed if you could exactly time the point at which the rake started to melt perhaps it would be fused in some areas but even if it were to be quickly plunged into the molten steel it would still have a slag coating from passing through the surface. As to candle dipping a bar I have no idea if this would work but it would be expensive to have a deep molted steel bath unless you were poducing many blades and since alloys are adjusted in the ladle and not the furnace maintaining heat could be very difficult. Speaking of Spraying Deposition, this is very common and I have a hand held unit I use in my home shop. The torch looks a little like a cutting torch with the cutting lever on the top. There is a socket on top that receives a bottle of metal powder. You use it like a cutting torch with the preheat used to raise the part surface temperature. When the lever is pressed the powder is sprayed throught the flame melted and blown against the part. It fuses and forms a coating that can be built up although I haven't have good luck with very thick coatings (1/8" to 1/4") since they can tend to flake or chip as the part cools. I have used spray deposition to build up worn shafts with mild steel powders which are machinable and lawn mower blades with carbide powder which is grindable only with Silicon Carbide "Green Wheels" and a vararity of material between these extremes. Seems like I learn about a new process or material almost every day. nitewatchman

SDI has a Rail Mill in that area where they roll new rail. A visit and a question might score you a drop. nitewatchman

I have a 12" and a 24" rock saw and use mineral oil in these. I get the oil at Walmart a little cheaper than anywhere else I have found. I will go in and buy out all they have, typically 8 to 12 quarts. Since they sell it for a laxative, I do get some funny looks. I have also found that it may be filtered through two brown paper bags one inside the other and it comes out as clear and clean as new. I have two plastic buckets, a five gallon and a seven gallon that fit insude each other. the five gallon has holes drilled in the bottom. the five gallon is placed inside the seven and the two bags placed inside each other and in the bucket. The dirty oil and rock slurry is added to the top and filters through the bag into the bottom.

You have yourself an antique. The code may not be complete but the first blush is a rail made in February 1954 of Open Hearth Steel to a Canadian Pacific Specification although this doesn't mean it was sold to CP or even in Canada The carbon content is likely .6% to .7% with some Chrome and it would not be heat treated or hardened. The "ball" or head will likely be hard due to work hardening. Welding should be done after preheating to 600F until soaked thru and then post heated for 1 hr at 600F and allowed to slow cool. E7018 electrode is a good choice, but E6011 or E6013 willl also work while pulling the carbon in the weld diffusion zone down slightly. The rail may be Heat Treated by heating to 1675F for 1 hour per inch of thickness and quenched in light oil. The quenched rail should be tempered quickly at 600F to 750F. Free advise so just remember what you paid for it.

Does the rail have any identifing letters or numbers on the web? This will suggest what the chemistry is as it can vary considerably from .4%C to 1.0%C. What is the width of the base and the height?

Just curious , did you attempt the AR repair.

Cape Chisel

An easy way to make a tapered reamer is to make it like a D Bit. Turn or form the taper you want and then grind one side away till you reach the diameter and hone flat. A fulfilling operation to make your own but I would just buy a Taper Pin Reamer.

Unfortunately there is no uniform specification for AR500 material other than hardness and the chemistry and Heat Treatment will vary from mill to mill. A representative chemisrtry is C-.30%, Si-.70%, Mn-1.70%, Cr-1.00%, Ni-.80%, Mo-.50% and B-.004%. Surprisingly the Boron @ .004% has a huge effect on the hardenability of the steel and an even bigger effect on the response of the Heat Affected Zone. In the HAZ where the temperature is in the 600F to 850F range the impact strength of the material can decrease to near zero due to the presence of carbides and untempered Martensite. We have learned this the hard way from Bainitic Frog Castings we have produced by adding Boron to induce Bainite. These were being investigated as an alternate to Cast Manganese Steel (Mn-14.00%) I don't think that you will be able to restore the strength and hardness of the repair unless you utilize a Hard Facing material with an as-deposited hardness similar to the AR500. If this material is used however the HAZ will likely crack due to the highly restrained nature of the "plug weld" and influence of the Boron. If the repair can be made sucessfully, reheatment of the entire target may be attempted. The structure of AR500 is tempered martensite which is obtained by a quench and temper operation. This should be accomplished by heating the material uniformly above it critical temperature to fully Austenize the structure. A starting point could be 1625F to 1675F and time at temperature should be about 1 hr per inch of thickness or in your case 20 to 30 minutes. Quench the material in light oil heated to 150F. After quenching test the material using a file. The file should skate across the surface and not cut the material. If the material is soft reheat and quench in cooler oil. While it may be necessary to obtain a faster quench, a water quench will most likely result in a cracked plate. After the plate has been quenched it must be tempered, using the plate without tempering risks the plate being shattered and creating shrapnel when struck by a bullet. The harden plate should be tempered to 350F to 400F for one hour after reaching heat. Check hardness using a file and comparing to an unaltered plate. Be prepared to do all of this again if it is too hard or too soft. Remember too hard - raise the tempering temperature, too soft - lower the temperature. If with all this effort the plate repair plug doesn't fall out on it's own, the plates don't crack and the hardness is okay, the repairs may still be punched out if a round hits the same spot. Good luck with your efforts. I also shoot pigs and chickens. I use a .22RF and a .22 Hornet in a Contender fitted with a 20X telescope.

Barrel wear seems directly proportional to velocity. I found that when pushing a .220 Swift over 4100fps (measured not guessed) the chamber throat eroded to the point that accuracy was affected in less than 800 rounds. If depending upon the barrel contour I could set it back an 3/4" or so, it was usually good for another 500 or so rounds. For a Remington 700 receiver this is quick work. So a barrel might start at 24" or 25" an be retired at 20". Usually it was easier to just sell it to someone less demanding. BTW - these were 4140 Air-Gauged .224" Douglas Cromoly Barrels

Best sharpening of file is done by sand blasting the teeth. The sand is directed to the back of the tooth at about a 15 degree angle.The sand cuts away the back and regenerates the cutting edge. The best way I have found to test the sharpness of a file is to run your finger across the face of the file along the direction of the teeth. Each tooth should leave a light very small cut. I also take except to not lifting the file after each stroke. Dragging a file backwards is essentially the same as not allow the tool on a shaper to lift on the return stroke. It rolls the cutting edge over burnishing the teeth and drags particles over the fresh surface. This dulls the file and can scratch the part finish. There is nothing quite the same as using a sharp file and draw filing a piece of metal by essentially pulling the file sideways along the part. The shearing effect of the sharp teeth form little curling chips. This right up there with making transparent wood curls with a sharp hand plane. To the original question, the best way to clean a file that I have found is to treat the teeth with chalk before starting and to use a file card or very stiff wire brush frquently to prevent buildup from forming in the teeth. If a booger does form, I pick them out using a sharp scribe one tooth at a time.

Band Saw for me, I start mine and go do something else. I come back after I hear the cut stock fall.

KROIL! Best I've found.

Railroad wheels are indeed still cast with the tread against a chill in some cases. We also cast manganese steel railroad frogs in our foundry with chills against the running surface. In both of these cases the chill freezes the metal very quickly at the contact zone resulting in very fine grain and promotes directional solidification. This tends to give better mechanical properties in the zone subjected to highest stress.

There is a simple answer. In steels the carbon is in solution and in cast irons it is not and resides in the grain boundaries as free carbon which is very weak and brittle. Think of sweetened tea where the sugar is in solution. The sweetening can be increased until it the tea is saturated and the liquid can hold no more and then the crystals settle out. In some steels the carbon can be very high. Manganese Steels can have a carbon content of 1.8%. The carbon is taken up in the solution at this range when the temperature is above 1900F and completely disolved. If however the steel is allowed to cool slowly the carbon comes out and forms a brittle material full of free carbon. For this material the manganese content would be about 18% (a 10:1 ratio) and the manganese acts like an Austenite stablizer. This allows the material to be water quenched from 2000F, retain the dissolved carbon, stay as Austenite and be dead soft after quenching. The cooling here occurs faster than the carbon can come out of solution.

Excuse me for bringing it up, the comment was said in jest!

Looks like a Black Powder shooter to me. Please read the next several post to see why this is a BAD idea. Deleting this post based on safety would have been correct, but would have also removed the reason it should never be done. The reason is much more important at this point. Nitewatchman, thank you for your post as it allows us to address a safety issue that otherwise would not have come up.

Steve, If you could send me a small piece I could Spark it on our foundries SpectroMax and see if it matches any common alloys. Might take a week or so. Contact me OL if you want. nitewatchman

Tungsten???? What a long strange trip it's been. (JG of the GD)