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Complete guide to hobby metal casting. Metal casting made easy. A complete guide for the hobby metal caster. Learn the techniques for green sand casting. How to select scrap aluminium & bronze, How to melt metal in your hobby foundry. Section two of this hobby foundry ebook will show you all the details and complete specifications to build a “Gas Fired Crucible Furnace”. The last section will show how to build the best labour saving device any, hobby foundry worker could wish for… “The Motorised Gyratory Riddle” will deliver silky smooth freshly conditioned sand every time. Eliminate “manual sieving” of your sand forever! This hobby foundry ebook has been written and compiled by Col Croucher. Australia. Copyright: Aug 2002. You are licensed to print one edition of this ebook. Please respect my intellectual rights. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 1 Complete guide to hobby metal casting. You are licensed to print one edition of this ebook . 1 Introduction to the backyard foundry . 4 The subjects covered in this ebook: 4 Castings from metal 5 About the author 6 DISCLAIMER. . 7 Operating and reading this ebook . 8 Moulding and foundry work . 9 Sand Mould Schematic Diagram . 9 Foundry equipment & tools. 10 Foundry tools 1a. 11 Foundry tools 1b. 12 Foundry tools 1c 13 Foundry tools 1d. 14 Making foundry patterns 15 Pattern making materials. . 16 Pattern draft. . 17 Core prints . 18 Pattern basics. 19 Silicon R.T.V & Reproduction patterns 20 Casting shake out time 21 Gates & Runners . 22 Reconditioning foundry sand . 23 WARNING ABOUT WET SAND 23 Eleven steps for sand moulding 24 Step two: Setting the pattern on the mould board . 25 Green sand & baked sand cores . 29 Using sand & steel cores. . 30 Building your gas-fired furnace. 32 Furnace lid lift arrangement. . 33 Scrap metal: what to melt 34 Melting scrap bronze metal . 35 Furnace ignition: Lighting up for the first time. 36 Follow These Steps: 36 Common Sand Casting Faults. . 37 Glossary: Common foundry terms . . 38 Judging temperatures by eye 39 The Home Metal Foundry. 40 Home foundry projects 41 Project 01:Door hinges 41 Project 02: Clutch slave cylinder . 43 Project 03: Timing chest back-plate 44 Project 04: M.G. T Type Aero Screen Base . 45 Green sand recipes . 46 Temperature Control Methods. . 47 The Pine Stick Temperature Method . 47 Simplicity! 48 Part 02 . 49 Building a propane gas fired furnace. . 50 Introduction 50 The furnace building materials 51 Notes Cont’d . 52 Sheet metal former 52 Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 2 Complete guide to hobby metal casting. Authors disclaimer . 53 Constructing the furnace . 54 Construction notes. . 55 The outer rolled steel reinforcing bands. . 55 Determining the furnace dimensions . 56 Furnace illustrations 57 Furnace illustrations contd. . 58 Furnace Floor Levelling Adjuster. . 59 Construction details of furnace frame. 59 The Upper Support Column. . 61 Furnace Lid Clamp Band. . 62 Furnace lid lifting & swivel mechanism. 63 Furnace building specification sheet . 65 Building spec sheet cont’d . 66 Designing and building the furnace burner. 67 The furnace burner illustration. . 68 The burner pipe venturi section . 69 Burner nozzle 70 Machining the gas Jet 70 Assembled gas jet . 72 The outer burner pipe 72 Air blast control. . 72 Controlling the air blast. 73 How to cure flame blowouts. . 73 Controlling the total gas flow . 74 The refractory material 75 Filling the furnace walls . 76 Old time refractory mix for crucible or cupola furnace . 77 The following steps are by volume & not weight! . 77 Running in your new furnace. . 78 Follow These Steps: 78 Different views of furnace 79 Furnace Views Cont’d . 79 Crucible specifications. . 80 Part 03 . 82 The Motorised Gyratory Riddle . 83 Introduction 83 Disclaimer. 84 Safety Hints 84 Riddle construction outline 85 Flexible Drive coupling 87 Rotating Disc Shaker Assembly . 88 Images for construction reference . 89 Self-Aligning Bearing Layout . 90 Sieve Cradle Clamp Assembly Details 91 Building methods: Gyratory Sand Riddle. . 93 Building sequence . 93 Building the riddle: . 94 Fabrication tips 95 Machining parts . 96 Welding 96 Operating the gyratory riddle safely. . 97 Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 3 Complete guide to hobby metal casting. Introduction to the backyard foundry. A worldwide hobby metal casting renaissance is occurring, hobbiest’s around the globe are re-discovering the metal casting skills and techniques of the “Old Masters, who achieved spectacular results using basic tools, equipment &“Know How”, learnt through many years of trial and error, as well as well proven methods & techniques. Don’t ever be afraid of making a mistake, for, without mistakes, you will never truly learn! The author has been metal casting for about thirteen years. All of the equipment needed for backyard foundry work was built in the home workshop. I call it my boutique foundry because it is so small. This 3-part volume hobby casting guide ebook will give you information on how to build all of your own foundry gear. You will need some basic metal workshop tools, e.g. Welder, angle grinder, power drill and other small hand tools that most people entering into foundry work seem to have already. Hopefully this will be the case with you. If you don’t, then why not do a joint project with a friend. Share the COST, and share the FUN. The subjects covered in this ebook: 1. How to melt & cast metals. 2. Building a Gas Fired Furnace. 3. Building a Motorized Gyratory Riddle. Section One: Metal casting Made Easy. T he topics covered in this ebook will range from making simple wood patterns & cores, preparing foundry sand & ramming up your mould boxes. How to select bronze and aluminium scrap metal to break up & melt into ingots to use later for your casting work. The various tools & equipment you will need for moulding work will be explained. We’ll discuss the different furnaces that can be built to melt your metal, (covered in the next section) plus a host of other material you will need to know about, to get started in this age old craft of “METAL CASTING” In this ebook you’ll find high quality photographs that accompany the text all the way through. The step-by-step sand moulding photographs and description will help you to fully understand the methods & techniques involved with moulding and casting metal. Hobby metal casting is highly contagious, and after a couple of sessions of melting and pouring, you will be hooked on the process. Your imagination and the skills that you develop will be the only limiting factor in your progress & success. When I started out fourteen years ago, there was very little info around for the home metal caster that made any sense, I searched high and low for the right books, (especially for info on die cast Al pistons) but found that most of them were for the foundry industry specialists. While these books were excellent for the purpose, they were not much help to the home foundry worker! Whether you intend to just make things for your own enjoyment, or you aim to get serious & gain enough skills to start making things for payment, is entirely up to you. Whatever you do, “DON’T RUSH" into trying to make money out of your venture, take it slowly, learn your craft, and practice all you can, which will help you to make the best product possible. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 4 Complete guide to hobby metal casting. Castings from metal. Bronze & Aluminium items are the result of greensand casting. Produced in the author’s home foundry. Greensand casting can produce quite fine details. Each of these items presented their own particular casting techniques, especially the crocodile nutcracker . Sand casting techniques. H ave been used for thousands of years to Cast Iron, Bronze, Gold & Silver artworks as well as simple tools and implements used by various civilizations, such as the Egyptians, the ancient craftsmen produced amazing bronze castings with their simple equipment. Teams of people blowing air down long tubes provided the heat to the primative furnaces. Society has now become more reliant on new technology, the old techniques of hands on small-scale metal casting have started to rapidly disappear into the annals of history. Except for the small band of interested people like you, who’ll help to keep the craft alive. Today there is a great resurgence in backyard metal casting; people wanting to melt & pour metal, can do so right in their own backyards, with basic tools & equipment. There is no rocket science involved! Whether you want to cast Vintage Car or Motorcycle parts, or you want to cast your very own Artworks in Bronze or Aluminium. Or, you just want to have a go at metal casting; this book has been written for you, the novice & semi advanced metal caster. There is nothing more satisfying than creating something, and showing you’re new found skills to your friends and family. This ebook will show & describe how to achieve metal casting results that maybe you never thought possible. As you learn basic foundry skills, you will be amazed at what you can achieve by learning and applying the simple skills of this intriguing craft. There are plenty of foundry sites around on the net that will simply show you some photos of home built items, but they do not cover the full details required to enable you to build the same item. Feel free to print one copy of this manual, but please respect my intellectual property & copyright. It is illegal to provide pirate copies of copyright work. If you want to use text from this ebook for some reason, then please email us for permission. I want you to treasure this ebook. You may print your own hard copy instruction manual to have by your side, to refer to when required. You can quickly look up and read about certain subjects or articles, or look at well illustrated pictures and plans, which help you to learn how to do all the different processes required during the moulding & casting processes. Or to build the equipment you want for your home foundry workshop. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 5 Complete guide to hobby metal casting. About the author. M y interest in metal work stems from my boyhood days, I was fascinated as I watched my father work the farm “Blacksmith Charcoal Forge” to heat metal to do repair's to farm machines etc. As a teenager I went to Tech College and studied all the trade courses I could find, even attending night classes over many years. Furthering my studies into foundry work, I now hold certificates in all foundry areas Inc, sand moulding, core production, foundry practice & pattern making. But I can assure you that the early days of my casting were done with much trial and error. (Plus plenty failures.) Building a go-kart project started me on the road to ”HOME FOUNDRY WORK”. The go-kart needed wheels, so the quest for ”casting know how” started. (In this e book you will see the turned patterns for the wheel project). By following simple pattern making methods I made useable wheel rim patterns and then cast the wheels. (Success at last) The First Furnace Built. This was the crudest contraption one could find, but it worked, I was able to melt enough aluminium to cast the Kart wheels after a couple of initial failures? (Remember… you learn from your mistakes). The furnace was built from a few old house bricks stacked up on the ground, to form a round container to hold a pile of fuel charcoal. A short length of 2” pipe fed into the bottom of the charcoal bed provided the air blast. (From a borrowed household vacuum cleaner)? Don’t underestimate the melting capability of charcoal. It is an amazing fuel. With the correct air blast, it will melt most metals (especially when used in a cupola furnace), it is quite effective when used to melt aluminium, and many hobby casters start out with a charcoal furnace. The only problem is the charcoal supply; if you cant make your own, then you may find it difficult to find a reliable supply. (We have a free charcoal-making guide available from our web site) Every furnace needs “Air blast”; you won't have to look for anything too fancy to supply a good quantity of air for your furnace. A good second-hand domestic vacuum cleaner will deliver plenty of air to melt Aluminium or Bronze in a Gas Fired Furnace. The domestic vacuum cleaner is an excellent choice to provide the blast for a charcoal furnace. Just check before you buy a vacuum cleaner to make sure the hose can be attached on an outlet socket to make it blow instead of suck, most important! There is nothing more satisfying, than creating something unique in your own workshop. Especially when you conceive an idea, make a pattern, ram the sand mould, pour the casting, and then finish it on your own lathe, etc. There are home metal casters all over the world creating their own unique products; you will be joining these ranks of backyard founders, creating your own special items. You don’t need sophisticated equipment to achieve good results with your home foundry operation. It certainly makes life a lot easier to use good equipment. But if you can’t afford to have the best right from the outset, understand that you don’t need it. Several years passed before I was able to build really good equipment, but, it was only after operating simple equipment, which enabled me to custom design and build an excellent Gas Fired Furnace, and the associated gear that went with it. I am still making equipment as required. The equipment is really just a miniature version of the big commercial gear. Always keep your eye out for good ideas that you can adopt to your foundry operation. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 6 Complete guide to hobby metal casting. DISCLAIMER. Foundry work is lots of fun. Y ou will get much enjoyment from your metal casting creations, but please take CARE when handling molten metal. Temperatures from 740DegC to 1300Deg C can inflict a very serious injury due to unsafe practices. Don't ever put wet scrap metal or ingots into molten metal, it will explode, showering you with molten metal. You are dealing with old technology here; the associated risk of injury should be fully understood by all who attempt this craft! Please go and buy protective clothing, eye & face shields, Leather apron & good quality leatherwork boots. Nothing will spoil your fun more than a serious burn on your body. I have experienced the pain of small splashes of hot metal. I can tell you it is “NO FUN” Please read this e book, not as an entire lesson on the art of metal casting, but more as an introduction to setting up your own backyard foundry. One section read by itself will “NOT FULLFILL” your needs, Although there is enough ground covered for most people to grasp the methods required to build your own equipment, and to do some good sand castings. This hobby foundry ebook has had worldwide acclaim for the info, and teaching it contains, but your learning should not stop with this ebook alone. Hobby foundry work is a journey of discovery & fulfilment as you learn the techniques of this intriguing craft. Seek out others with an interest in metal casting & learn from them also. Building your own foundry equipment. The tools and methods explained in this e book have worked extremely well for the author. However there are lots of tools & equipment that you will be able to construct your self. Arc welding will be involved in the construction. If you feel that you are a competent welder, then by all means go ahead and make your own tools. Please be careful if you are constructing a pair of CRUCIBLE TONGS. Think what would happen if the lifting tongs “Failed” while removing a full crucible of “molten metal” out of the furnace, it would not be nice, would it? If you are not a competent welder, go find someone who is! Perhaps you have a friend who is interested in what you are doing. Combine your talents to create the things you need for your foundry. With a combined effort, you will soon build the basics to get started. Then you can move onto the more advanced facets of sand casting. You are accepting responsibility for your own actions. The Author “WILL NOT” be held responsible for carelessness on your behalf. I have no control over the way you conduct the practices in your home workshop. All I can do is warn you to be very careful in the way that you carry out your craft. Abide by the rules and everything will be fine. Be CARELESS and you will PAY for it through INJURY. Your foundry equipment can be fabricated with normal tools, machines & equipment found in well-equipped home workshops. At times you will need to have access to a lathe. The machined parts will not be complicated or difficult to make. Basic lathe turning methods will suffice, & I’m sure that most people who are attracted to metal casting would already have reasonable machines in the backyard workshop. If not I would suggest that you talk with friends who may know of someone who can help you out. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 7 Complete guide to hobby metal casting. A nother way to get access to good workshop machines, is to enrol in a night class at the local Tech College… and work on your own projects…simple. The course will be worth every penny you pay for it. Operating and reading this ebook. • This ebook has been written and compiled as a PDF ebook; it is readable on any computer platform providing you have the FREE Acrobat Reader installed on your computer. • All images displayed within are copyright of “Coljan Photography” Australia, May 2003 • International Copyright protects all Images & text appearing in this eBook. Images are Low - Res, watermark embedded. • If you are new to metal casting, please read the book as a whole, and not just in sections, the more experienced metal caster may choose to read individual chapters if they are familiar with certain operations. • Navigation from start to finish is quite simple, choose any page from the bookmarks or contents shown, and use the black forward & backward arrows to go from page to page. You can also enlarge or reduce the font size to fit your computer screen for easier reading. • Click on the bookmark tab and the entire major subject heading titles will show as an index for easy reference & selection. • If you place your mouse arrow on the side scroll bar and click the mouse & hold it down you will notice a small side bar with all the page numbers shown. This method can be used to find a certain page very rapidly if you know the page location or page number. • This ebook requires an encrypted operating password. If you obtained the password other than from our website then you may have an illegal copy, please email us for details of how to correct that situation. • http:\\www.myhomefoundry.com Or email us at: mailto:colin@myhomefoundry.com For more information visit our web site: Quote. Use what talents you posses. The forests would be very quiet indeed If the birds that sang there Were only those that sang best. Author unknown. **** "A man only learns in two ways, one by reading, and the other by association with smarter people" ==Will Rogers== ***** Tuition is high in the school of experience and there are no free scholarships. Benefit by the experience of others. == ANONYMOUS == Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 8 Complete guide to hobby metal casting. Moulding and foundry work. M oulding is the process where a pattern is pressed or imbedded into special sand to the desired shape or form. Or the pattern can be placed on a moulding board, and the sand is rammed or compressed around the pattern. After the pattern has been carefully moulded, rapped & extracted from the sand mould, the mould is lightly blown out (to rid the cavity of loose sand particles) closed, & molten metal is then poured into the cavity. When the metal has cooled, the casting is extracted from the sand complete with gates, runners & risers attached to the raw casting. The Home Foundry worker will principally be involved with Green Sand Moulding and casting. Other forms of sand casting can be used, but for now, we’ll concentrate on the green sand method. Your green sand must posses the following properties: Porosity: To allow air and steam to escape from the mould during casting. Cohesion: Ability of sand particles to cling or adhere together while the mould is being rammed up. (Bentonite is the binder used for this purpose) Refractoriness: Ability of the sand to withstand the severe heat of the molten metal. For Aluminium castings, the green sand needs to be a fine grade. (ASF 80 to 130). If you have sourced your sand from a commercial foundry, it would most likely be about right for you to start using in your home foundry set up. Sand Mould Schematic Diagram Section view of Green Sand Mould box. Study the above diagram carefully; this is the type of mould box that would be used in a commercial foundry operation. Spend some time studying this sketch; there is a lot to be learnt from it. Use this sketch as a reference at any stage of your casting work, you may learn more from it as you improve your skill levels. NOTE: The set up above would normally include an internal core! Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 9 Complete guide to hobby metal casting. Foundry equipment & tools. Quick Tip: For a Cheap Starter Crucible . Weld a plate on the bottom of some heavy pipe (4”w x 6” tall) lined with a mixture made of fireclay & graphite, will make a good cheap crucible. Dry it carefully before fireing to cure the lining. A plain steel pot can be used for small melts, but pieces of oxidized metal will flake off and end up mixed with the melt. Crucible. The crucible is the vessel used to hold the molten metal, they are available in many different sizes, and a good size start out with is a number 6 or 8. You need a crucible that holds about 6 to 8KG of Aluminium. Capacity is quoted by weight in Bronze. Ask your supplier to help you with your choice. You will find suppliers under foundry supplies in the yellow pages, or on the net, silicon carbide crucibles are the best quality crucibles. Cheaper clay graphite crucibles are also available at a lower price and may suit your purpose. Mould Boxes. You will need one or two to start with. A handy size to have is 10 X 12“ X 3” constructed from steel or wood. They are made in two halves, the bottom is called The Drag; the top one is called The Cope. I chose steel for mine, which is a lot stronger, and will last a lot longer than wooden boxes. Steel boxes won't burn when hot metal is spilt on them, which does happen. The boxes need to have a pin register at each end to provide an accurate register for the mould boxes during the moulding operations. Identify matching corners with coloured paint or marks of some sort. There is nothing more frustrating than putting your mould boxes back together the wrong way around, and only realizing this after you have poured & retrieved your ugly casting from the sand mould. Plastic Rubbish Bins. You need at least two bins, use them to store your green sand; the sand is not really green in colour. The colour is really quite black. You use water to temper or condition the sand, so that you can ram it around your patterns and mould with it. Your sand will keep nice and moist in the bins for several weeks. You will find that there are periods where you might not do any casting for a month or so. If you could not keep it moist during that time, the sand would need complete reconditioning all over again. Hand Ramming Tool. A simple device, turn this item on your lathe out of hardwood, one end is round and flat like a large hammer and the other end is wedge shaped for getting into corners etc. Just make the part that you hold in you hand a comfortable fit. Make your hand- ramming tool to the size you require. Two or three ramming tools could be made up in different sizes to suit the different size mould boxes & patterns you might have. Written by Col Croucher Australia. You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property. 10 [...]... allow a generous amount of feed metal to supply the casting as it solidifies When casting a nameplate, you need to make a runner that feeds the casting in equal points all around the casting to avoid this problem Feeders & risers The strategic placement of risers or feeders will also promote sound castings and even solidification It is not unusual to find almost as much metal used for gates and risers,... mould board Made cheaply from a piece of timber or some metal, put some handles on it and it’s ready to use Written by Col Croucher Australia You are entitled to one Printed edition of this ebook, please respect my copyright and intellectual Property 14 Complete guide to hobby metal casting Making foundry patterns B efore you can create any casting a pattern of the object to be cast must be made in order... from the sand, give the casting a thorough check to make sure there are no cold shuts, miss runs, or metal pulls, shrinks, caused by insufficient metal feed to heavy parts of the casting Sometimes it may take two or three goes at getting a perfect casting from a new pattern Opening the mould box This is what you will find when you open the sand mould box (Cope & Drag) A sound sand -casting, & hopefully... size For secure retention in the casting, machine some grooves on the outside edge, then locate the nuts in the mould where required The molten metal will run into the grooves during casting When the metal cools, it will shrink even tighter onto the captive nut, they are not likely to pull out of the casting (The buttons or nuts also act as heat sinks or chills on the metal) After this operation, holes... hobby metal casting Reconditioning foundry sand Due to the intense heat of the metal castings, the moisture that you so carefully put into the sand will be driven out This used moulding sand will now have to be put back through the sieve to have the correct amount of water added to it Reconditioning of the sand (By adding a small percentage of water, about 4 to 6%) is essential after every moulding & casting. .. little to make it sit upright while more sand is placed into the mould box Sometimes a riser is essential to feed metal back into the casting as it cools, but for this casting it is not essential, as the wall thickness is much the same all over the casting (Always feed to the heaviest part of the casting) Keep placing the sand into the box, and keep ramming until the box is full, and you have achieved a... learning to do your own metal castings you not only save your self-lots of money you also have much more control over the total process Once you become confident with the whole metal casting process, you will no longer have to wait for someone else to do the job for you Just crank up the furnace, ram your sand mould up and just do it your self You can easily see that green sand casting is not that difficult... intellectual Property 28 Complete guide to hobby metal casting Green sand & baked sand cores After mastering the art of moulding and casting with solid patterns I suggest you try your hand at creating hollow castings, such as bearing blocks or large round collars with a hole in the middle Very often a pattern can be constructed so that when the mould is made The pattern will create its own green sand... hobby metal casting Note: The silicon RTV 585 is mixed with a catalyst 60R Mix gently to avoid air entrapment in the silicon Complete instructions are included with the RTV kits Casting shake out time Quick Tip This is the part of foundry work that you look forward to, checking the success or otherwise of all your hard work This casting looks OK at this stage & most do, however after extracting the casting. .. caster’s are never quite sure what kind of scrap they should melt for their castings The best source of Aluminium metal is scrap cylinder heads, inlet manifold castings, & gearbox casings if you can be bothered stripping, & cleaning the muck of them Try to source your metal privately, or from engine repair workshops Scrap metal yards will rip you off when they find out what you are up to Beware also . guide to hobby metal casting. Metal casting made easy. A complete guide for the hobby metal caster. Learn the techniques for green sand casting. How. melt & cast metals. 2. Building a Gas Fired Furnace. 3. Building a Motorized Gyratory Riddle. Section One: Metal casting Made Easy. T he topics