Ok I think I need t really excel on the polish... I got the sand blaster and the dremel action going, but I am thinking mirror shine now... Thinking more wheels and more of those compounds. Looking into this: https://www.amazon.com/gp/aw/d/B07QJ4BW5N/ref=ox_sc_act_image_1?smid=A1E9WAJ0W6DAFO&psc=1 And this: https://www.amazon.com/Drixet-Buffi...7HWB04MDHQY&psc=1&refRID=N4SNEPEK97HWB04MDHQY What are your thoughts?
Mirror finish is a royal pain. You'll be ages if you are think of spinning this stuff on a drill. Look for a cheap bench grinder that you can remove the guards off of. You can then pick a pad and some rouge. You'll still have to progress through the stages. When you polish something, you remove the scratches left by the previous step. And so on... So bead blast, 400grit, 800 grit, 1000grit, 1800grit, 2400grit, 3200, then you'll finally be on the wheel. After that, you end up around 6000. For a really fine finish, it's big work. I really don't recommend it unless you are really bored. With details, you then have to decide how best to handle those areas in between. Why are you still getting chunky looking bronze? It's been awhile, but are you making home made bronze or just still not getting hot enough? Take another picture of the christ up close, I'd like to check out your surface finish. Looks good from 3feet away.
Yeah it looks like chunky style chili. I'll have to dig through his old threads, but we've seen this issue before on his work. If it's just in his cup, he's getting lucky. Maybe its divine intervention saving his work?
Well I still have a lot to learn. One of the shells must have got some silica in it before the pour... Ok Jason I will stop messing with the recycled stuff and buy some 16# ingots in the morning. Do you have a code I can give them so they know you sent me? Here are some close ups of before sand blasting, and then close ups of the better of the two, but as you can see sand in the surface finish.
Ps. The piece shrank 1/16-1/8 inch overall, so I also got shrinkage and it wont fit in the cross. After 6 kids with the misses, this a first for me. If I toss a little blue bill in before the pour will it prevent this issue? I am going to use these two to practice polishing and give them to a carpenter to make wood crosses for gifts or something.
Nahh... No code. Just order the smallest size they have. It's the same price I believe. And the fat 16lb ones really suck to cut to fit in your crucible. Ok.. the sandy look could be caused during boil out. If you boiled too long, it will remove the slurry and leave the silica which would lead to a bumpy inner surface of the shell. OR you really did get some dry silica inside when you were patching so there is that possibility. He still looks great! No one will notice and I'm not telling. Some thoughts..... Think back to when you boiled. Where they on the same sprue or where they boiled out separately from each other? If apart, how was the timing? Did you have to go take a crap mid boil? How was the boil? ROARING boil is what you want, the faster the better.
I wouldn't touch shot. I'd rather cutup 3inch fat boys given the choice. There is lots of smaller options on this page. https://www.budgetcastingsupply.com/category-s/1855.htm Price isn't the best, looks to be about 8bucks a pound. Maybe it went up since I bought my load. Pay the man. I left about a grand behind, it's your turn buddy! Look on the bright side, FREE SHIPPING!
Shot is pretty nice for smaller crucibles, you can scoop out and weigh what you need and dont have to cut up ingots. But be careful with them when adding more shot to already molten bronze. Some of the shot will be hollow inside and does "pop"
You could always tig the defects out. Repair it and grind back. I sometimes also get pits like that. Usually a shell problem when I mix up the batch of slurry wrong. Over firing the ceramic shells or over heating metal also seems to make surface texture worse. I think the cooler you pour the less shrinkage you get. And judging by the blackened sandy surface you poured hot?
717-394-0753 lancaster foundry supply in PA $4.10 per lb of silicon bronze. They can ship 3 x 18# ingots in a usps box for 15 bucks shipping. I think that works out to about $4.40 shipped per lb. Of course they are 60 miles from me so I just drive there when I need metal and choose all the small ingots so they don't need cutting to fit my crucible.
The what stamp now? Its silicon bronze the real stuff. It works with bronze tig rod and blends seamlessly. Its what I use for all my stuff. I'd just say you heard about them from this forum. I'm not sure if they remember me. I made the bronze eagles and humming birds. They might remember that but who knows. They sell to hobbyists like us.
They've had me on nights working 14 to 15 hrs a day for a while now so I haven't been aware of the world. Will have to track down the video and catch up.
I called Tuesday on my long commute. Pretty informal, the lady who answered gave me the owner's number, I called him. He has a couple of different types, I think he said "evader" is the stuff, no clue about a cmx, and it is made in Toronto I ordered some from him, I will start a new thread with picks of what he sent and cost, for you guys.
