Hello From Medford Oregon USA, 9KG Furnace Kit??

Discussion in 'New member introductions' started by DonF, Nov 15, 2024.

  1. FishbonzWV

    FishbonzWV Silver Banner Member

    I like cast iron muffin trays. My favorite is the corncob style, they make a nice slim "crucible topper upper".
    IMG_3435.JPG
     
    Tops and DonF like this.
  2. DonF

    DonF Copper

    What is the process for cutting the ingots out of the cans? Just a cut off wheel on a die grinder and go at it? I do generate at least a few scrap tin cans a week. That might do until I have a chance to go to the goodwill or other second hand place. I do have an old small loaf pan that appears to be made from sheet and gas welded on the corners. It's even got some rust starting. It's a little large but I think it could work in a pinch. The bottom measured 3"x7" so as long as I didnt fill it up too much I could use that and still fit it in my crucible. With the angle on the pan it gets big fast.

    [​IMG]
     
    Last edited: Nov 19, 2024
  3. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    Flip your muffin pan upside down and use it as a pattern for a molding sand ingot mold for those copper alloys, they won't braze to that. I built a custom drag-only flask fitted to a multi cavity mini loaf baking pan that makes convenient sized ingots. Quick to ram up, sometimes even reusable. Hard on a small heap of petrobond sand though I think, if you do it again and again. So I have switched to thick walled welded angle iron ingot molds recently.

    Jeff
     
    DonF likes this.
  4. Petee716

    Petee716 Gold Banner Member

    Yes, a cutoff wheel will free them up. Strip the paper off as best you can and heat them up over the exhaust just before you pour. That will burn the plastic coating out and will dry them out too. (assuming you've washed the dogfood out. Lol.)
    Your pan will work great as long as it isnt teflon. You're right about the depth. Any more than an inch deep will be bigger than you want. I made that mistake with commercial bread pans and ended up having to saw them up into usable chunks.

    Pete
     
    DonF likes this.
  5. DonF

    DonF Copper

    Last edited: Nov 22, 2024
  6. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    Somewhat related, a friend of mine found this antique molder's toolbox in his travels, with many similar tools in it, many made by Frost & Wood co., if anyone is familiar?

    IMG_20241122_110843_645.jpg

    IMG_20241122_110848_421.jpg

    IMG_20241122_110852_523.jpg

    IMG_20241122_110856_362.jpg

    He won't part with any of it but I might get a chance to try using (copying?) them one day. Until then, as to your question, my modified spoon has been adequate for any types of scooping, slicking, cutting, etc. that I've encountered. But it would be really cool to try the real thing.

    This is a free to browse copy of the US Navy foundry manual, there is some info there about different molding tools:
    https://maritime.org/doc/foundry/index.php

    C.W. Ammen's The Complete Handbook of Sand Casting describes the intended use of various different types of molder's trowels and slicks. Worth trying to track down a copy to reference IMO, I got mine in the Kindle store.

    As you say though, it's not so detailed that it will tell you when slick A is more appropriate than slick B. For that I would imagine you just have to get your hands dirty and improvise. With some use, you'll get accustomed to those tools just like any other, and eventually you'll just know which one to grab at any given time because that's the one you like for <whatever you're doing>. Someone else here has probably used real molders tools, hopefully they can say more.

    Keith Rucker on YouTube has a video where he goes through an old molder's toolkit and talks about the different slicks etc. a little... but I can't find it for some reason. And he's only dabbled with sand molding himself anyway.

    If you start out with a dollar store spoon or two and bend/grind them until you like how they work for coping down, cutting gating, slicking sand etc. though, you'll have enough to get going with IMO and maybe along the way you'll find more detailed info somewhere or realize why you might need a particular slick. You can always upgrade later if you need to.

    More examples of molder's trowels just for fun:
    http://smelko.com/?page_id=477

    Slicks:
    http://smelko.com/?page_id=476

    That company has changed names and addresses, but some interesting pieces of the old website remain.

    Good luck,

    Jeff
     
    Tops and DonF like this.
  7. DonF

    DonF Copper

    Another book I found useful is this one - Foundry Practice-A Treatise On Molding And Casting https://www.survivorlibrary.com/library/foundry_practice-a_treatise_on_molding_and_casting_1909.pdf It seems oriented to cast iron, but a lot of the info crosses over to aluminum. On page 10 of that book, printed in 1909 there is a picture of the pouring basin style that most attribute to the author John Campbell, but this book from before the guy was born obviously had the idea first, but was not explained well. Pages 76 and 77 have a little of the information I was looking for but again not a lot of detail.
     
  8. DonF

    DonF Copper

  9. DonF

    DonF Copper

    Before I coat the bottom of the Amazon furnace with the Satanite coating... It came with a little round "fire brick" Do I set that on the insulation and coat over the whole mess? It seems like coating the insulation then putting the firebrick on top may crack the coating. Yes I have a lot of questions! Ha ha. Also on salvaged cast aluminum. I am fixing up a silver deck John Deere mower and purchased one with problems for some other parts. It has a big cast aluminum deck that is not salvageable. Its painted and dirty. Do I oxide blast the fragments before melting. It seems like a lot of crud to just be stuffing in to melt unprepped. If its too much trouble to save for melting with all the contamination I can toss it and stick to cleaner sources of scrap.
     
  10. Tops

    Tops Silver

    I coated the ceramic fibers first on mine before installing the plinth. I have swapped plinths so I am glad they did not get cemented in any fashion.
    You'd probably be happier with cleaner metal to start, especially if it was cast once before or a known good alloy for casting.
     
    Petee716 and DonF like this.
  11. DonF

    DonF Copper

    Thank you for the tips!
     
  12. DonF

    DonF Copper

  13. Tops

    Tops Silver

    DonF likes this.
  14. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    Tops and DonF like this.
  15. DonF

    DonF Copper

    Thanks for the tips! The mifco one really isn't that bad of a price if it lasts longer. Does the cheapo sensors sleeve have to be graphite? I did see that the end was open on the K type thermocoupler. I am thinking getting that in the aluminum would be bad. There are a few premade sleeves but they all seem to be stainless also, but with a closed end to the thermocoupler would not get contaminated. https://www.aliexpress.us/item/2251832782315122.html? amazon has a lot of them also under immersion sleeves. https://www.amazon.com/s?k=Immersion+Sleeve
     
  16. Al2O3

    Al2O3 Administrator Staff Member Banner Member

    This subject comes up often enough, I should really make a sticky for it because a contact pyrometer is such an essential tool.

    If you use a bare stainless sheathed, K-type in metal contact, they will usually fail in short order.

    I haven't used the MIFCO probe and cannot comment on its life, but most here who have speak favorably of it. Many use carbon gouging rods as the protective sheath for K-Type TCs like you linked. For either, if you will use it to measure metal temp while the crucible is still in the furnace, you will need to build an extension wand protect the leads and your hands from the furnace heat.

    After I figured out the carbon sheath can't be continually exposed to the furnace atmosphere, I've been using the one described in the link below for 8 years and have only replaced the sheath several times, twice because broke it through careless handling. With care, I think you can expect 100-200 dips. The gouging rods are very inexpensive ~$1.50 each, and can be purchased in 5-packs at McMaster Carr. and you do have to be able to drill them to receive the TC.

    Cheap Pyrometer parts list | The Home Foundry

    There are other threads here on the forum on shop made versions. If other links are posted here, I'll see if I can assemble them into a sticky.

    Best,
    Kelly
     
    Tops and DonF like this.
  17. DonF

    DonF Copper

    Thank you all for the tips! Its been very helpful!
     
  18. DonF

    DonF Copper

    My face mask from Amazon showed up. It's not bad. Its feels like its made for small to medium head sizes. Definitely a tight fit. It does cover the chin and neck area better than with a traditional face shield. It needs real glass rather than plastic, but the lens size is common. I haven't decided if I am going to remove the welding shade flip up or not. I have had times where the standard welders mask was too big to get my head in somewhere. though. https://www.amazon.com/dp/B0C6N2ZL4F?
     
    Last edited: Dec 6, 2024
  19. DonF

    DonF Copper

    Thank you to all that have answered my questions and offered advice! Its appreciated. I have the parts needed for a thermometer on the way, the mr volcano lining is here I just haven't had time to paint it on yet. The tools I will figure out for sand casting as I go. I don't think they were as necessary as I originally thought as I see a lot of home casting people getting good results with modified spoons. On protective clothing... I have my leather welding jacket. The leather hood is here, with a clear glass insert on the way. I have leather gloves and some old leather boots. So the last part is pants? I have heavy jeans and an old pair of flame retardant mechanics coveralls. Would two layers of cloth be OK or should I invest in some leather pants? Some of the pitfalls of youtube is you see everything on the spectrum of protective gear from full aluminized suits in real foundries to the barefoot/sandal guys pouring in the dirt. Someone on youtube mentioned I needed to clean my crucible out after use? I can't find any info on that.
     
  20. Tops

    Tops Silver

    I opted for a leather welding apron with split legs and spats to cover the rest of my shins and tops of my boots.
    amazon_gear1.jpg
    Crucible cleaning: it hasn't been an issue for me with aluminum. Once I pour the melt and any leftovers for ingots, there is just a thin layer of 'foil' in the crucible which I can remove while hot and/or wait until the crucible is cool. There may be better practices than mine in this matter.
     
    DonF likes this.

Share This Page