R Funk

I appreciate the warnings from others on CO as it a real hazard in non open areas in which propane forges are operated. We tend to "overfuel" propane forges resulting in high CO output. That is one reason they have dragons breath as some of you call it. This should be reminder to all as we operate propane forges in our enclosed shops during the winter. One other item I wish to point out is all propane cylinders have a pressure relief valve on them they may relieve in the case of over pressure and for other miscellaneous causes, ie mechanical failure. If the valve relieves it would fill the basement with an explosive mixture. This the one of the reasons the cylinders say on them do not use or store in an enclosed area. Propane gas is heavier air which makes its use in basements problematic as it tends to collect. A relief valve opening, a leak or failed ignition could cause pockets of gas to collect. Natural gas is lighter than air and disperses more readily. I doubt your insurance company and local fire marshall would look kindly on this device being operated in your basement.

I see no real reason why the leaf spring helv must be straight. It may take some tweaking of the design to use an arched spring. Using a forge to straighten a spring would be relatively easy but getting a quaility heat treat over such a long item is beyond the capability of many blacksmiths. A spring shop with heatreating facilities would appear to be a desirable option I would be scared to take a leaf spring and cold straighten it and use it in this type of application where a spring failure could be fatal without a subtantial guard. I would plan on using used springs, if I were building one, but we must keep in mind spring failures on trucks are very commom and a used spring may fail due to fatigue at any point. (speaking as a former tractor trailer driver and a road side scrounger who picks up broken springs for forging stock) Use a multileaf spring pack should be used to reduce the negative results of a spring failure as a single leaf failure will not be catistrophic. Also add enough clips on the spring pack so the a broken spring leaf will remain in place if it breaks. The good news is that leaf springs usually fail a leaf at time so inspect the spring pack daily for cracks near the center of the spring. If broken leaves are ignored then the pack can fail catastrophically and wack our vulnerable heads or other anatomy. This is a cool design and as an mechanical engineer it appears to be one of the best options for a shop built mechanical hammer.

The question you need to answer is do you want to make your handles or buy your handles. Hofi and Tom Clark for example make their hammer handles. Thus they can standardize on what they prefer. Each of their handles are fine quality and are great for the applications. I beleive Hofi has a posting in "Blueprint Section" on how he makes his handles. I have been able to find low priced commercial handles and have a 5 gallon bucket half full of them. The current commercial low cost source of handles is Menards. Home Depot and Lowes handle pricing is ridiculessly high. I have picked many of my handles up at fleamarkets when I lived in Missouri, the home of many handle manufactures. In either case standardize on your handle eye size and shape and make a set of drifts that correspond. Most sledges have a standard size eye from 6-16 lbs or so. I have had no problem fitting commercial handles in to commercial sledges in the 10 or so I have fitted (no I do not break that many I buy them or modify them and then install handles) On the smaller hand sledges and ball peins it is more or less the luck of the draw and most require fitting of the handle. I often soak the end of the handle in oil as it provides lubrication which makes it easier to install and reduces loosening due to drying out of the handle.

Charcoal is made by the controlled combustion of wood in an atomsphere with limited or no oxygen. This process is called pyrolysis and most commomly occurs between 600 F and 1200 F for wood. Simplistically pyrolysis consists of driving off all material from the wood except carbon and ash (non combustibles) via heat. The material driven off is principally moisture and hydrocarbon type materials and are referred to a volitales while the remaing material is fixed carbon and ash. The volitales results in the majority of the smoke and flames we see when we burn wood. The fixed carbon is what we generally see as the "coals" remaining after the flames are gone. However in a fire were the oxygen supply is uncontrolled, such as a campfire much of the fixed carbon is burnt along with volitales due ample oxygen supply. When we make charcoal we desire to preserve all the fixed carbon possible as this is the charcoal. BE VERY CAREFUL! MAKING CHARCOAL PRODUCES CARBON MONOXIDE! AS WE ALL KNOW THIS IS A VERY TOXIC GAS. The process can be divided into to 2 basic processes, direct and indirect. The direct process is a controlled burning process where the wood is burned in atmosphere with limited oxygen and some of the wood and fixed carbon is burnt, producing heat for the pyrolysis or charcoal making process. This process would include all processes where a fire is actually lit in the charcoal producing wood and combustine is controlled by limiting air supply (oxygen) to the wood. This is less efficient as some of the wood goes to fuel the process instead of being converted to charcoal. It is the most common method of charcoal production in most parts of the world. The indirect process involves heating the an enclosed container such as a barrel as shown in the link included earlier in the thread. It is a superior process as none of the fixed carbon, the product we want and call charcoal is burnt if the continer is indeed air tight. The off gases from the pyrolysis can be burnt to provide heat for the process and in some commercial applications are condensed for chemical making applications. The process of making coke from coal is pyrolysis and a very similar process to making charcoal excepting the scale of production and specialized equipment utilized for the making coke for iron blast furnaces. Historically charcoal was made by carefully piling wood and covering with dirt and leaves leaving a vent hole in the middle. The "coaler" would start the pile on fire and live with the pile for several days carefully tending the pile, controlling the air flow into the pile by manipulating air vents (holes in the dirt/leaf cover) to control temperature. After their judgement indicated that the process was complete they would completely seal the pile from air infiltration and allow it to cool. When it was cool the charcoal was removed from the pile. This type of process is still used in 3rd world countries. This process was improved with permant concrete bunker type structures with steel dampers replacing the dirt covered piles of wood. During the 1930's,40's & 50's the states of Missouri and Wisconsin in particular encouraged the use of this structure to produce charcoal. These structures were approximately 30' X 60' in size and 12' high. They were piled full of wood, ignited and the temperature and cumbustion process was controlled by limiting air supply. In the lower midwest they were referred to as "Missouri Kilns" They produced large amounts of pollution in the form of unburned volitales (smoke) and at one time were the largest air pollution source in Missouri. More recent technology includes rotary kilns or hearths which converted sawdust and planer shavings to charcoal for briquetting purposes. I would suggest that using the barrels or small concrete or brick kiln 3' x 3' x 3' or so would be the prefferred technology. Constructing a pile of wood covered with leaves and dirt would work but will require more attention and if the covering of dirt fails and air is addmitted in a uncontrolled manner, you have just created a large bonfire, not a charcoal producing system. Building a fire and qenching with water has 2 problems. 1) Allowing the fire to burn long enough to pyrolyse the inside of the wood will result in significant loss of fixed carbon (charcoal)due to the readily available oxygen for combustion. 2) You have almost no control over temperature and burning paterns. This will result in burning much of the fixed carbon that you want for charcoal A sealed or semi-sealed system will allow you preserve as much carbon (charcoal) as possible.

RR rail is generally in the range of 1070 to 1095 steel. The newer and heavier rail is generally on the upper end of this range (140 lb/yd) and the older and smaller rail is in the lower end of this range (100 lb/yd) This would be an appropriate steel for many tools including hammers. However this is a plain carbon steel and has some limitations. MAKE CERTAIN THAT THESE TOOLS ARE APPROPRIATELY TEMPERED! High carbon plain carbon steels are very brittle unless appropriately tempered. Most commercial hammers made after World War II are alloy steels containing chrome, molly, nickel and similar alloys. These alloys improve the toughness and hardenability of the steel. These are desirable atributes. However plain carbon steel was used for many years with satisfactory results. Blacksmiths used plain carbon steels from the mid to late 1800's upto the current time. Expensive blacksmith tools with good reputations are still being produced from carbon steel.

Hauling compressed gas cylinders in the passenger compartment of a car is scary. A minor leak could create explosive enviroment. In the passenger compartment of a car are multiple sources of ignition. Sparks/arcs are generated by the ignition switch, the brake light switch, the seat belt warning system etc etc. Accetylene may form an explosive enviroment waiting for a small spark to ignite it.... Oxygen may form an atomosphere where fires burn very agressively and sometimes explosively.... I have seen photos of cars that used to exist before a compressed gas cylinder they were hauling leaked.

I usually lay my cylinders down as I feel it is safer than hauling them upright unless you have a very good way of securing them upright. There is nothing wrong with laying O2 cylinders down and I go through O2 much faster than fuel. Dodge is exaclty correct on the Accetylene. They must be stored upright for period of time equal to amount of time they were layed on their side and longer is better. I have spare cylinders so I am in no time pressure to use the cylinder I just got so leaving them upright at least overnite before usage is not an issue. By the way per DOT rules you can haul 1000 lbs of compressed gas cylinders before you need a "placard" on your vehicle, so for most of us that will not be an issue. Of course toxic or corrosive gases have smaller limit. Your insurance company will be very unhappy with you if you need a placard, especially if you have an accident.

Glad to see your post! Trust you are doing well! I just joined recently as well. I have been ill and off work for 9 months so I have more time to read and particpate. I trust to begin telecomuting for about 4 hours per day beginning any day now. Computer connectivity and security is always a fun issue..... Ruben

Need to Correct previous post Charpy V notch testing is a methodology to test the relative fracture resistance of the steel. The test does ****NOT*** reflect the exact toughness of the steel in real world applications but reflects the relative toughness of the steel. The units on Charpy V are foot-lbs and the higher the number the tougher the steel and more resistant to fracture. Sorry the table of hardness and Charpy V did not come out better. The 3 columns are Material, hardness and charpy and the numbers underneath but cramped to the left is the data

I did some digging on steels, particularly hardness and toughness. Charpy V notch testing is a methodology to test the relative fracture resistance of the steel. The test does reflect the exact toughness of the steel in real world applications but reflects the relative toughness of the steel. The units on Charpy V are foot-lbs and the higher the number the tougher the steel and more resistant to fracture. Material Hardness (Rc) Charpy V (ft-lbs) H-13 47 18 H-13 52 10 D-2 55 22 D-2 59 19 S-7 59 85 S-7 55 122 Note: Values are at room temperature. H-13 becomes much more impact resistant at higher temperatures. I was unable to locate data on 1095 and Charpy V although catalog information described 1095 as brittle when low temperature tempering or drawing temperatures were used and resulting high hardness. When tempered or drawn at higher temperatures and resulting lower hardness, the world brittle was not used. As to whether 1095 was surface hardened and interior left tough, this would most likely require oil hardening baths. After reading numerous historical and recently written refernece books on mining, I have not seen any reference to quench baths of oil. I agree with Skunkrvr that Grant or others might be a good source for information. Of course he may be using 1095 or similar as he is competing in the comercial market as opposed to the highly specialized competive drilling contests. S-7 should be "oven" heat treated with a carefully controlled temperature and be held at quenching temperature for at least one hour (1 hour per inch) and air quenched for maximum results and "double drawn" at the selected tempering temperature. I would recomend using stainless steel foil covering to prevent surface decarbonization of the tool. It is possible to heat treat S-7 in the forge but the results are less uniform.

1095 or something very similar (high carbon no alloy steel) was the historical steel that where used for drill steels in mining and quarrying applications. Alloy steels (chrome, nickel, molly) were not really comercially widespread until after WW II and thus 10 series, plain carbon, steels were typically used for this application in the past. I am somewhat surprised that 1095 is still being used for championship hand drilling contests. Modern alloys would be better. Is there a requirement for hex stock or steel? Many older hand drill steels were made from round stock (I have serveral)

I am not certain of the financial limitations but I would look at other steels. The cost of participating in drilling contests must be relatively high with today's gas prices (thanks to the enviromentalists preventing drilling and refinery expansions) the cost of drill steel material may be incidental in the big picture. Adding chrome, molly & nickel add to hardnesss of steel but most importantly add to toughness or chip resistance of the steel. A sure way to lose a rockdrilling contest is to have the corners of the cutting edge chip. The priorities of drill steel are 1) Chip or impact resistance (toughness) as I said earlier the sure way to lose is with a chipped drill steel 2) Abrasion resistance or hardness. This will result in durability of the drill steel. 1095 has only hardness in its favor. It does not have alloys that add toughness. 1095 requires a fairly agressive quench to obtain the required hardness. This creates locked in internal stresses that make 1095 more prone to chipping and cracking. Tool steel is quenched slowly, maybe even in ambient air, giving time for the internal stresses to equalize, reducing the tendency for chipping of the cutting edge. If money were no object I would look at tool steels. D-2 may be a good choice as it among the tuffest of all tool steels, but I am not aware of anybody using it for rock drills. S-7 is a no brainer selection possibility. If this guy is serious about winning, testing of various drill steels with various heat treatments would be in order.

Steel and Wrought Iron exibute a ductile to brittle transition at cold temperatures. Perhaps some of you remember the Liberty ships breaking in two in the North Atlantic. Brittle wrought iron failures at cold temperatures have been documented since the middle of 19th century. This transition from ductile to brittle can occur as warm as 30 deg F. I would recomend that tools and anvils not be used when their temperature is less than 30 deg F to prevent brittle failures. Earlier in this thread Sandpile relates how he broke an anvil when using it while it was cold. I have several anvils missing either heels or horns. I have often wondered how many of these broke while being used at cold temperatures. I would recomend preheating tools as they are more likely to fracture at cold tempertures. This will not only protect your anvils and tools but also protect personal safety as we have all heard stories of fragments of steel flying from tools and causing even fatal injuries.

Charcoal is a very acceptable fuel for forging, however I would us "lump" charcoal not briquet charcoal. Briquet charcoal has a lot of foreign material in it. Since raw charcoal is relatively expensive they add ground limestone which is cheap and a chemical compound to improve combustibility. I am sorry I don't remember the exact compound but I knew 20 years ago and if I remember correctly it is a chemical that we don't want near hot steel. My first reaction it contains sulfur but I am not certain. You can see the limestone, as ash, remaining after the fire is out. Sometimes I have had briquets look nearly whole after they are burnt due to the quanity of limestone ash.

The socket end of lug (where the size goes from ~1/2" to ~1-1/4") makes a good mandrel for forming the "funnel" type top for candle holders on candle sticks. The material is most likely a medium carbon steel (1030 to 1060) and would be good for tongs, limited us chisels and punches, unless they prove more durable, and smilar applications. This material should be water quencable (sp) followed by tempering to improve toughness. Of course remember these were all made by the low bidder so steel quality is most likely not the best.

Great Idea! This would even be better for those who burn coke as it goes out quickly if the air flow is stopped. This should substain the fire. On a side note one of my elctric blowers for a coal forge is a forced draft fan from a high efficency residential gas furnace. I paid $0.50 for at a flea market. It is not big enough for 2" stock to forge hammers, but for small sections such as 1/2" or 3/8" stock it works great.

As a general rule I would not recommend modern detergent engine oil for lubricating gearboxes and bearings. (yes I am aware that some truck transmissions recommend 50 wt engine oil) The engine oil has additives that can cause corrosion and other similar problems. The detergent is a prime culprit The modern engine oil is designed to keep foreign matter in suspension. This is not what wanted for gearboxes and bearings It would be better to use a non-detergent oil or a gear oil. Wally World still carries a non detergent oil, I am not sure why..... I have some for gear box, bearings and hydrostatic drive purposes.

There are 2 answers if coal needs a cover.... 1) If you plan on using your entire coal inventory in a short period of time (a year or less you probalbly will not have any problems. 2) If your coal inventory will last you more than a year I would cover it as some deteriation can occur. A $5-$10 dollar tarp may be a good investment if this was the case.

I read an interesting historical blacksmith book on line (I don't remember the title, sorry) This blacksmith advocated using a horizontal pipe with holes drilled in it and not use a clinker breaker with this design. One can adjust the length of fire by opening up or plugging holes in the pipe. The pipe should run all the way through the forge so you can use a poker type device to punch out any ash that may fall in. He spoke of a clinker breaker as an unnesecary(SP) complication caused by design of our fire pots. I have seen forges like this in the ruins of blacksmith shops in the western hard rock mining regions. These blacksmith shops were very busy busing and heavily utilized sharpening hundreds of drilling bits per day so the design must have some merit. I can not vouch for the pipe design myself but it is interesting enough to give me pause and think about the concept.

Be very careful with electrical and electrical power tools on your work table if you weld on your table. I went out and bought the supplies to "electrify" my table and then began thinking. Some of the electric power tools use are 3 prong grounded tools. I had planned using grounding 3 prong electrical outlets I installed on my table. I also do a lot of arc welding on my work table. If the grounded electrical power tool is laying on the table and it provides a better ground than the welding ground, I have most likely just smoked the tool by putting 100 plus amps of welding current through the tool as it is the ground path of least resistance. This applies whether the tool is plugged into an outlet on the table or into the wall or extension cord. Likewise if you have grounded outlets on the table and the conduit and outlet boxes are grounded to the table as the NEC Code would most likely require, and the welding ground were poor, Welding current could flow through the #12 wiring supplying the table and fry your table and shop wiring (I admit this is a gray area in the code but I feel most inspectors would look at the table like a frame of a machine which require grounding... Of course you could use all pvc conduit and boxes and possibly avoid this issue) I am lucky I did not fry any of my tools with welding current through the ground before I thought this through more carefully. Bottom Line: Make absolutely certain that welding table has a good ground to your welding machine so welding current will flow through the welding ground lead and not the elctrical ground and/or the power tool ground Use only double insulated tools if you intend to lay them on the welding table or hang then on parts of the welding table that are grounded. Perhaps a wooden shelf liner to lay the power tools on under the work is a additional level of electrical safety (I stored my 5 Dewalt 4.5" grinders as well as my 6" and 9" grinders under my bench on a shelf, each with a unique wheel so I don't have to change wheels Trust this assists in preventing anyone from smoking any tools as when the factory installed smoke comes out it is very difficult to get the smoke back into the tool and make it work again.