Jump to content
Scottyice

Slag Removal

Recommended Posts

Hello everyone, I'm recently new to the forum, and want to thank everyone who shares their knowledge on these forum pages. I have been reading for a couple of months now just learning the to do's and not to do's. I finally got setup yesterday and was able to start my first melting project which prompts my first couple of questions. I am using a Lee's production 20# pot, and the lead I'm melting is a old bathtub lining.

1. When I get the lead melted and fluxed what is the best tool to remove the slag from the top of the melt? I have never melted lead before, but seems like a lot of trash on top of the melt.

2. When I removed my lead from the mold it doesn't look smooth, it almost looks grainy on the outsides of the jig head. Is my lead not hot enough or my mold not warm enough?

3. Once I remove the slag from the lead, the top of the melt seems to look almost like its cooling down on top. Is this normal?

Link to comment
Share on other sites

1. Skim with stainless spoon. Size depends on the size of the pot your smelting in.

2. Your jigs or whatever your making will take on the characteristics of your mold. If it's a do it sand cast mold it won't be as smooth as a CNC cut machined mold.

3. Sometimes the surface will take on a sheen like appearance dependant on your mix of lead you're working with. Are you fluxing? If not, I would suggest it. It helps remove the contaminants and makes your pouring so much better. Flux and flux often.

Link to comment
Share on other sites

A word of extreme caution. I live in SE pa. and winter air  temps. can drop to 5+/- degrees @night. I only heat the insulated shop during the day . Slag removal spoons can get very cold  and I strongly recommend you heat them 1st by placing them over the lead pot while the lead is heat. Inserting a cold spoon( with any moisture on it) can result in lead jumping out of the pot - 6-8" up and up to 1 foot forward into you face.

Link to comment
Share on other sites

I bought a spoon from the thrift store for dirt cheap and I use it to skim my lead.I think it cost me 25 cents.

Try fluxing with a small piece of wax first. Make sure the wax catches fire first and stir while it's burning making sure to wear gloves and safety glasses during this procedure.

As Smallmouthaholic said heat the spoon before putting it into your hot lead.

Use a metal coffee can to put your skimmed dross into.Then properly dispose of it when it's full.

Link to comment
Share on other sites

Thanks for the suggestions guys. I still don't think something is not right with the lead though. Yesterday I melted 22#'s of lead making small muffin ingots. I fluxed the lead ( marble size bees wax into the lead, small square of paper towel thrown into the smoke, it catches fire and I stir until the flame is extinguished) and removed all of the slag from the top. Does the slag almost look like sand? Today I took some of the ingots I made yesterday and melted them down, fluxed the lead again, and took more slag from the top. It seems like every time I stir the lead more of this sand stuff comes to the top of the pot. Is my lead to hot or not hot enough? My spout is getting clogged everytime I try filling one of my jig mold.

Again, Thanks for your help guys.

Link to comment
Share on other sites

Sounds like your lead and pot are dirty. Bottom pour pots don't like dirt. I would empty it and look inside. There's probably gonna be some dirt clinging in there. If there is, clean it out. Then melt your scrap down in another pot(cast iron) and flux until you know nothing is left in it but lead. Scrape the edges and bottom a lot because they hold dirt and won't let it float up. Only put ingots you know are absolutely clean in the lee.

  • Like 1
Link to comment
Share on other sites

The old bathtub liner you melted down had years of dirt and oxidation, you will have the same thing happen with old lead pipe, I made that mistake. What temp are you running the pot on? I ask because you have a nice size pot and the slag should not be getting into your spout and you say your slag looks like sand, it should be really dark and it makes me think you aren't hot enough. You should also fill your pot so it is full, maybe 1/2" from the top but most of it sounds as if you are just getting the lead hot enough to melt and your jig heads not being smooth, well that could be the mold. What I would like to know is your jig head shiny? It should be shiny and free from wrinkles, it will have a little texture to it as the mold is sand cast and not machined but I'm wondering if they used any zinc in the bathtub liners because what you are describing sounds like zinc contamination, it that is the case your entire pot of lead needs to go and the pot needs to be cleaned out, I had it happen to me and it was the last scrap lead I ever melted.

Link to comment
Share on other sites

I'm not really sure what temp I'm running the lead, I have it set on 9 when I first start the melt. Once it's liquified I reduce it down to a 7. I guess I should get a thermometer so I can see that kind of thing. I also see I must not be filling my pot with enough lead I'm only filling it right at half to three quarters full. I'm using a Do-It Brush Jig Mold, the lead is shiny when I can actually get lead to come out of the pot. I know for sure a lot of my problem is lead flow out of the pot. I think once I get some good clean lead my problems will reduce.

Thanks for the input, once I get some new lead I will try again, I twill take the rest of the tub lead and trash it.

Link to comment
Share on other sites

Smalljaw I tried what you told me about filling up the pot almost to the top and it totally changed the lead in my pot. Once the lead liquified and I fluxed I had very little slag on top of my lead. And let me tell you guys I am so glad I read the best ways to flux your lead topic. Because if I wasn't expecting that wax to catch fire like it did, I would have thought I had a really big problem on my hands.....

Thanks for sharing your knowledge.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...


×
×
  • Create New...
Top