First official casing since I finished building the furnace and dolly. Using the Lost Foam method. My bench top grinder base broke so I actually haD a legitimate project here other than just melting some metal and pouring ingots. Learning phase Don't use DW mud to fill voids before casting. Make sure your pouring cup to the filler sprue is over sized some any dross which may be hiding that wasn't previously removed can float to the top of the casting and into the cup. Kelly advised me that his castings did the same until he started using the aluminummmm tape sprue cups. Due to the gases present during pouring I can only assume at this point of time that 1 or 2 hollow relief risers would really help. Down side is you'd need a lot more molten metal to completely fill everything. All in all, it'll serve it purpose which it's intended for.
Hey OCD, congrats on first pour and success! Welcome to the stinky sand club. How many pounds is the actual part and what temp did you pour at? Looks like it almost poured short but you got there. Happens a lot with LF....think its a fail and then it's not. Couple things for you to consider if you plan to do much lost foam: Keep your eye out for a steel 5 gal can to use as a flask. I use the plastic ones too but mostly for small parts. It’s only a matter of time before you have an over pour or run out and then the aluminum will go through the plastic bucket like it’s not there and run all over the ground. Bigger parts close to the wall will soften them up to deflection and potential failure. Not sure what you used to vibrate sand. Just rapping works fine but for more intricate parts with undercuts, you’ll want vibe. Make yourself a sifter from aluminum window screen to sieve the drywall mud and debris out of your sand as you put it back into the bucket. Keep a snap lid to store it so you don’t have to smell the stuff. The concrete driveway is great for dumping and cooling the sand. If you have a water bucket handy, the drywall mud usually just falls off during quench and it adds some temper to the casting. I haven’t found that vents do anything because they are not a vent until the molten metal reaches them. You can place bobs on your pattern but it’s debatable how much they add, same principle though if you have more massive areas. I haven’t found hollowing any foam out to be helpful. In most cases it’s unhelpful because you want the foam there to retain the sand in place until its replaced by metal. The exception is the hollow foil sprue but they fill more or less instantly. I love the smell of burnin’ polystyrene in the morning….Your neighbors are gonna love ya. In general Your furnace and burner look to be working like a champ!! You need to ditch those channel locks and get yourself some longer tongs to keep your hands out of that beast when you are feeding it metal. I have the same problem and am just looking for a cheap pair or freebies I can weld some longer handles onto. Make yourself a tree or a stand (freestanding or attach to an outrigger) to hang your pyrometer, and maybe skimmer and tongs on. It keeps everything handy yet out of the way. That carbon sheath will end up broken without one and that’ll piss ya-off. I use the crane arm on my rig to hang my pyrometer. Best, Kelly
Way to go OCD! As you say, it looks like it will work quite well for the job it was made for. Congrats! Jeff
OCD, We need to find you some longer tongs to charge with!! Then maybe your hands will not be smoking each time you add metal to the melt. But that pretty rig seems to work well!!
The crucible is a A6. I had that thing slap full, within 3/4" from the brim. The base weighed out to 4# 3.5oz.'s cooled. My thermometer was reading 1627* when I removed it but by the time I actually poured it I'm guessing it was around 1500*. Yeah, yeah, yeah, I know I need to make a pair of tongs/grippers longer than a pair of channel locks but it's SO much more fun playing with molten metal with your hand on fire. I went to HD and picked up 100 lb.'s of play sand. That stuff is really fine. I just smacked the sides of the bucket and rattled it around some before pouring. I only started brushing the burnt DW mud off in the video to inspect the casting. Afterwards I did thoroughly spray it off with the water hose. Oh, you mean like this? Although the DW mud stayed in place and they wasn't any leakage from the encased mold just the heat alone fried the side of the bucket. Here's the chunk of dross that came out of the sprue and what you seen fall off in the video.
Looks like a success! One thought I had: you should either fab up a pair of tongs to charge your ingots into the crucible, or got a by a pawn shop and buy the biggest pair of beat up, ugly channel locks you can find. I think you might enjoy not dipping your hand into the furnace to charge it.
Good job John... No worry the vents didn't fill.. It's better to be lucky than good any day! Isn't casting metal like opening christmas presents at the end of all the hard work?? Good times. Found a song for ya. Kelly, thats a good idea about welding some some longer reins on a pair of channel lock pliers. It's cheaper than buying gloves every time!
Great job with the new furnace. I really like watching other's melt and cast metal. Looks like you have quite the balmy weather. Casting in paradise I would call it. And it is interesting to count the seconds before the gloves overheat. I think you set a record for holding the gloves in the furnace the longest time; makes for a hair-raising video for sure.
Talking of fabbing up some tongs, this reminds me of a time when i was ready to charge my partially filled hot crucible with another ingot of bronze and discovered a 'friend' had 'borrowed' my tongs. I wasnt as manly as ocd so quickly welded some 1/2 inch rebar to some old pliers. This worked so well that i havent made a 'proper' set to replace the borrowed pair for years. John
No problem. At first the handles of the pliers that became the gripping faces of the tongs were a bit slippy but a few grooves with an angle grinder and they have no problem gripping 10kg ingots.
#METOO... lol. I've been using my blacksmithing tongs but they don't open wide enough to grab fat ingots of the pretty stuff.
Yeah, was thinking the other end of pliers/channel locks might not open wide enough for 1/4 of one of those big 15# bronze ingots the way I cut mine up... Jeff
Got some time to finish this little project off. Since the original base was paper thin pot metal and the base I casted is 7/16" thick I need to install 2 longer anchor bolts. To do this the grinder motor housing had to be opened up. Then a press plate to move the armature winding out of the way so new longer anchor bolt could be installed had to be made. On one end the ID x 1-1/2" had to been ground/thinned out to be able to fit around the windings with damaging them. Then a 1/2" piece of flat bar was attached for beating/tapping on winding assembly evening moved out from over the bolts which required replacement. After all that was done it was a matter of reassembly and drilling attachment holes 1 step at a time. Then total disassembly was required to prime and paint. All wires had extensions and connectors added for ease of reassembly. Then all the wires and components were reinstall and bolted to my work bench. NOTES: Although I numbered everything during disassembly, it is strongly advisable to mark or scribe alignment marks on the housing case and the end caps to save yourself some aggravation during reassembly.
