Navigation |
Best Lead Melt Flux?
Started by hawnjigs, Jun 30 2008 12:18 PM
82 replies to this topic
#1Posted 30 June 2008 - 12:18 PM
I've tried WD-40, wood dust, powdered charcoal, paraffin, even dried grass & leaves, and have settled on beeswax as a personal choice. Other opinions?
#2Posted 30 June 2008 - 02:55 PM
Hawn,
You know to tell the truth I've been melting lead since I was a kid and I have NEVER fluxed my lead!!! Truthfully I'd have thought WD40 would cause a fire. I've seen all the posts about it but never tried it. Fatman Edited by Fatman, 30 June 2008 - 02:56 PM. #3Posted 30 June 2008 - 05:25 PM
Fatman, until I joined TU I never fluxed either with the exception of spraying WD-40 into heated lead free slag which helped separate the remaining metal from the oxides. And yes, it did flame up. But after reading TU posts about fluxing lead melt with wax I found that the pouring quality seemed to be improved. Sludge contaminants in the melt converted into powdery floating residue easy skimmed off the melt surface.
#4Posted 30 June 2008 - 07:31 PM
I use paraffin wax. It's the most widely available, consistent, and cheapest melting fluxing material I've found-- and it fluxes all lead alloys very well. However, most any oil will work fine, and old cooking oil or animal grease will certainly flux lead (but it's messier to handle than a chunk of parrafin). Bulk parrafin is easy to find, and even old candle ends are usually very easy to come by.
I use beeswax for making bullet lube, and it's much more expensive than parrafin, so I reserve it for that use. Fatman, Yes, fluxing will make a difference. I've met several people who had never fluxed their lead during a lifetime of pouring. Lo and behold, after trying it, they no longer had those problems they figured were just a part of lead pouring! Give it a try. #5Posted 30 June 2008 - 07:38 PM Fatman said: ... You know to tell the truth I've been melting lead since I was a kid and I have NEVER fluxed my lead!!! Quote Truthfully I'd have thought WD40 would cause a fire. ... Fatman #6Posted 01 July 2008 - 02:43 AM
Let me see if I have this correct......add some paraffin wax directly to my melting pot? I pour quite a few large cannon balls for halibut and ling fishing (16-40oz) as well as smaller for Sturgeon and Salmon (1-6oz). Will this help to get a smoother pour and release?
Thanks, Chad #7Posted 01 July 2008 - 03:48 AM SeniorChief said: Let me see if I have this correct......add some paraffin wax directly to my melting pot? I pour quite a few large cannon balls for halibut and ling fishing (16-40oz) as well as smaller for Sturgeon and Salmon (1-6oz). Will this help to get a smoother pour and release? Thanks, Chad Yes, exactly. Just drop a chip of wax about the size of a marble onto the surface of the melt. Be ready to stir it in thoroughly with a long-handled spoon or ladle. Also be ready for the wax to catch fire and flame-up for a few seconds. Keep stirring until you see a bunch of powdery black crud floating on a surface of silvery, shiny metal. Skim off the black crud, and start pouring. When you add more lead or ingots, you should flux again. Only takes a minute or less, but avoids a lot of frustration later on. A basic rule-of-thumb that virtually all highly-skilled lead pourers adhere to is: Head-off any problems before you start pouring. Fluxing is an integral part of that strategy. After fluxing, you should see that the melt has a smooth mirror surface. It certainly should help your pouring go smoother, as long as you're doing everything else right. I used to pour a lot of salmon balls in 1.5, 2, and 2.5lb sizes. By removing the lead oxides on the surface, and making the melt less likely to form oxides, fluxing will help make sure the metal is as fluid as possible, so pours go easier. But please read up on fluxing before you do it. There is plenty of info here if you do a quick search for "flux". Now, as far as helping the lead molds release the lead castings, well, that's a different issue. First, inspect a cooled cannonball sinker from your 'sticky' mold, and you'll likely see some scuff or scratch marks along the mold part lines. There's a burr on the mold edge that's causing those marks, and that's your culprit. Locate that area on your mold, and file, scrape with a knife edge, or sand down the offending burrs. There may be several, and they may be small, so search carefully. This problem is very common on large cannonball molds, as they often see a lot of hard use and abuse-- but the good news is that it's fairly easy to fix. Also, be sure to smoke the mold cavities thoroughly with a sooty flame (again, part of the "avoiding problems before they start" rule). This will help with both fill-out and mold release. These several changes to your pouring practice should make a big difference for you. Let us know how it goes. Hope this helps, good luck! #8Posted 01 July 2008 - 04:39 AM hawnjigs said: I've tried WD-40, wood dust, powdered charcoal, paraffin, even dried grass & leaves, and have settled on beeswax as a personal choice. Other opinions? Hey Hawnjigs, could you give us a run-down on your own experience with those fluxing materials? I have used parrafin wax for a while now, as it's easy to work with and inexpensive. It will flame up, but to me that's better than lots of smoke (the flames incinerate and substantially reduce the smoke). I have also used sawdust, and it works OK. Some folks seem to prefer it to other fluxing materials. I don't have a ready supply of sawdust, and don't wish to store any, so it's not a convenient option for me. I once had some rosin on hand, and used it to flux a few batches of lead. Works extremely well! However, rosin smokes like a pile of wet leaves, so for me....... no more rosin! I have used old cooking oil on many occasions, and it works great. A little messy to use, since it's a liquid, but it fluxes very well and flames up which is good (smoke bad, flames good). Free and effective is good too! However, the french-fry smell may give you the munchies while melting down scrap lead, which is not good (munch first, melt lead second, and not the other way around). I think the first flux I ever used was Brownell's Marvelux flux. It is a white powder (looks like salt) that comes in a jar, and a little bit of it goes a long way. It will not flame-up at all, won't smoke, and is nice to work with. It is claimed that it will reduce or prevent rusting on the sides of the melting pot. However, it's less readily available and more expensive that parrafin, so I no longer use it. Parrafin works as well for me, and since I melt outside, a few flames are of no concern. However, for anyone who pours lead inside their shop and wants to avoid smoke & flames, Marvelux may be the way to go. Here's a link: MARVELUX® BULLET CASTING FLUX at Brownells #9Posted 01 July 2008 - 06:57 AM
This a pretty good thread even if you never intend to melt lead or pour it - a read like this goes under the heading of something new I learned today. Thanks sagacious for some timely information. I hope that others that read this will add it to their melting and pouring processes; add to this, be sure to wear eye protection and welders gloves, keep food and drinks away so you give yourself lead poisoning, and make safety an active part of your processes, and I think that pretty much covers most of the bases. Good job guys!
#10Posted 01 July 2008 - 09:15 AM hawnjigs said: I've tried WD-40, wood dust, powdered charcoal, paraffin, even dried grass & leaves, and have settled on beeswax as a personal choice. Other opinions? I originally started with candle wax, I had laying around the house. It was excellent. Then I bought a candle at a store to replace it, and to my lack of knowledge at the time, I put a small piece in, and it flamed up and I almost got burned. Stupid me, tried to see what the wax was going to do. Not all candles are made the same, Hence the mishap above. After that I started to use beeswax, and have done that to this day. The only thing the beeswax does is when its dropped in it smokes a lot. #11Posted 01 July 2008 - 12:35 PM Quote
Hey Hawnjigs, could you give us a run-down on your own experience with those fluxing materials? Since supply is limited in my location I often have to deal with mystery sludge contaminated lead and in my experience out of the many I've tried beeswax flux seemed the most effective at powdering the junk out of the melt. Cost not an issue since candles including beeswax are often a garage sale bargain. Suggest beginning fluxers(outdoors) go straight to solid wax of some kind and not bother with foul smelling and possibly hazardous experiments. Never tried but Marvelux might be a good option indoors. Yes, beeswax does smoke a lot and doesn't seem to flame up in my experience. Edited by hawnjigs, 01 July 2008 - 12:41 PM. #12Posted 01 July 2008 - 01:32 PM
Hey guys, this is great dialogue, I am learning more and more so keep posting. Since moving to spincasting, the lead I use must be a pretty exact alloy of lead, tin and antimony to achieve error-free casts. I was buying this already blended from one of the big boys in St. Louis until the prices skyrocket overnight. Now I scrounge up where I can and do a lot of mixing myself. Not exact by any stretch and the relults are obvious when you don't get it right. Occasionaly I still pour from the pot and this fluxing subject has really been of interest to me as I never fluxed either.
Sagacious, you are a boatload of knowledge on lead and I hope you keep the open line as I have learned a bunch from your posts. And Hawn, I feel for you man, being stuck way out there on that island, I appreciate all your posts on the subjects as well. Ever need a hand, just holler. My thanks to all. #13Posted 01 July 2008 - 02:57 PM
"reeves", haha another non-fluxer out of the closet. US industrial supply price of lead down to $.79 per lb. today from a high of $1.70 last year, maybe your (ex)supplier will adjust price? Making a precision lead alloy outa scrap especially with antimony added gotta be tough!
Definitely, Thanks to "sagacious" for sharing with us, and would like to mention that all comments & questions are valuable in topic discussions and appreciated. #14Posted 01 July 2008 - 03:55 PM cadman said: ... The only thing the beeswax does is when its dropped in it smokes a lot. Quote ... Yes, beeswax does smoke a lot and doesn't seem to flame up in my experience. OK, I'm somewhat perplexed on this point: Why do you guys allow the beesway flux to smoke? When fluxing, you're stirring the melt, and stirring always cools the lead. During fluxing, you generally want to keep the temp up (especially during just that short time) to allow for oxide separation and chemical reduction. Note that the oxide scum floating on the melt will always be slightly cooler than the melt itself, and considerably cooler when stirring and skimming it. Allowing the flux to smoke creates an oxidizing environment, whereas lighting the smoke with a match creates a reducing atmosphere. The flames create a temporary spike in temperature right where and when you need it, and I've found that with some types of lead scrap (especially lead covered with lots of oxide, mixed with a large amount of foreign material, or lead granules) that the additional heat dramatically accelerates and maximizes efficiency of the fluxing process. But even when fluxing tire weights or other scrap lead, lighting the smoke speeds up the fluxing process noticeably. Then there's the safety factor. Any hydrocarbon flux may spontaneously ignite while fluxing. And as some have noted, it may ignite when you're hovering over the pot and not expecting it to burst into flames. If you light the flux right as the process starts, the flames start and stay controlled, and there are no unexpected high-temp surprises. Beeswax smoke may ignite spontaneously if the temp and conditions are favorable, of course, since that's how beeswax candles work. Besides that, wax smokes like a house fire, and the smoke lingers when it's not lit, so the pot smokes for a while. When lit, the hydrocarbons are converted to CO and CO2 much faster, and the particulate matter in the smoke is broken down. Stated simply, flames = much less smoke, and better fluxing. Now, I can understand why one might not wish to light a flame inside a shop or basement, but then again, I can't see why anyone would want billowing smoke (with the implicit risk of fire) in that location either. I know that beeswax smoke smells grand, but is there something else I'm missing here? Edited by sagacious, 01 July 2008 - 03:59 PM. #15Posted 01 July 2008 - 04:07 PM reeves said: ... Now I scrounge up where I can and do a lot of mixing myself. Not exact by any stretch and the relults are obvious when you don't get it right. Occasionaly I still pour from the pot and this fluxing subject has really been of interest to me as I never fluxed either. ... You've probably learned a lot by having to blend your own alloys. Either when pouring spincast, or from the pot, adding fluxing to your routine will enhance your results. I would expect that to be especially true when spincasting, as the reduction in both surface oxides and surface tension significantly promotes complete mold fill-out in small cavities, narrow/thin spaces, or detailed molds. Fluxing (done right, but it's pretty simple) should be one of those things that, once you start doing it, you should see the benefits immediately. Instant gratification, who doesn't like that? #16Posted 01 July 2008 - 04:11 PM reeves said: And Hawn, I feel for you man, being stuck way out there on that island ... #17Posted 01 July 2008 - 04:25 PM
"sagacious", my allowing smoking flux was from ignorance of match lighting as an additional fluxing tool. Previous flux choice WD-40 would always spontaneously ignite (sometimes quite dramatically!) and since wax didn't I thought smoke was normal to the process. Thanks for the tip, guess I'll need a longer stir spoon. And yup, I can spot potential melt pot fillers at garage sales & swap meets from an exceptional distance.
Edited by hawnjigs, 01 July 2008 - 04:31 PM. #18Posted 01 July 2008 - 05:02 PM
Ha ha, very good! I supect that you're ignorant of very little when it comes to lead alloy or tin alloy pouring.
I hear ya, my buddies say I must be able to 'smell' lead from 50 yards away. Like you, if it can be melted, I'm on it! #19Posted 01 July 2008 - 06:27 PM sagacious said: OK, I'm somewhat perplexed on this point: Why do you guys allow the beesway flux to smoke? When fluxing, you're stirring the melt, and stirring always cools the lead. During fluxing, you generally want to keep the temp up (especially during just that short time) to allow for oxide separation and chemical reduction. Note that the oxide scum floating on the melt will always be slightly cooler than the melt itself, and considerably cooler when stirring and skimming it. Allowing the flux to smoke creates an oxidizing environment, whereas lighting the smoke with a match creates a reducing atmosphere. The flames create a temporary spike in temperature right where and when you need it, and I've found that with some types of lead scrap (especially lead covered with lots of oxide, mixed with a large amount of foreign material, or lead granules) that the additional heat dramatically accelerates and maximizes efficiency of the fluxing process. But even when fluxing tire weights or other scrap lead, lighting the smoke speeds up the fluxing process noticeably. Then there's the safety factor. Any hydrocarbon flux may spontaneously ignite while fluxing. And as some have noted, it may ignite when you're hovering over the pot and not expecting it to burst into flames. If you light the flux right as the process starts, the flames start and stay controlled, and there are no unexpected high-temp surprises. Beeswax smoke may ignite spontaneously if the temp and conditions are favorable, of course, since that's how beeswax candles work. Besides that, wax smokes like a house fire, and the smoke lingers when it's not lit, so the pot smokes for a while. When lit, the hydrocarbons are converted to CO and CO2 much faster, and the particulate matter in the smoke is broken down. Stated simply, flames = much less smoke, and better fluxing. Now, I can understand why one might not wish to light a flame inside a shop or basement, but then again, I can't see why anyone would want billowing smoke (with the implicit risk of fire) in that location either. I know that beeswax smoke smells grand, but is there something else I'm missing here? I'm confused, or I just don't understand. #20Posted 01 July 2008 - 07:11 PM
Man this is one of the most enlightening threads ... I have poured jigs off and on for over 40 years, yes I have "Fluxed" all ways with candle wax (some would burn some would not all ways with smoke) ... But there are several things that have been brought out by you guys with this store house of knowladge on metals that blows me away (Sagacious for one) .. but I never really stirred it .. would skim off as well as scrape down the sides and bottom .. really did not know what the heck was going on except I was getting the trash to the surface .. Thanx for a look into what is going on with fluxing. This is as good a thread as the one about different metals a while back. Wish I could contribute .. all I can do is soak up this Info.
Thanx Again JSC |











