Thank you for sharing what you are doing - so inspiring! - and the beautiful space you have created with your artisans. No advice from me either - just glad you’re here.
@Judy_Bjorkman I’ll look into the Cratex wheels, been looking for a good quick option for obtaining a nice smooth edge on the sheet brass, this might work if I can source it of course.
I’ll definitely look into finding nitric acid. Will this get rid of the copper surface or just the excess flux and black crud from soldering? The vinegar/H202 does work okay, but results can vary in a production environment as the H202 becomes less and less effective the longer we have it mixed up and exposed to light.
Regarding your books, what a kind offer Judy. I would be thrilled to have so many resources to share with our team. My partner Maddy and I bounce back between the states and Malawi so we could haul them over next time we visit the states. I’ll message you here shortly. Cheers!
@nataliehanson Thank you for the encouraging words, glad to be here as well!
Kyle, sorry to be so slow responding! Nitric acid will not do a good job of getting rid of excess flux and black oxidation — that must be removed in the pickle, ahead of time. The nitric acid gets rid of the red copper (oxide) surface, and exposes the lovely gold of the brass. As for effectiveness, the dilute HNO3 does last longer (and works a lot faster) than what you are presently using. But after a time, it too becomes less effective, and you must add more acid (very carefully!). At a certain point, it becomes very dark blue-green and it may be hard to see whatever you are bright-dipping. Then you may want to start with a new dilute solution. Getting rid of the weakened nitric acid must be done carefully. There are several options for this — perhaps someone here can recite them. If not, I’ll look them up.
I’m in the process of boxing up my jewelry-making books and would be happy to mail them to North Carolina, when the time is right, and when I have an address for you! There are some of my books which I am not giving up — e.g., Tim McCreight, The Complete Metalsmith Charles Lewton-Brain’s book on Fold-Forming, and a huge book on the jewelry of Alexander Calder.
All the best, Judy Bjorkman
No worries Judy!
Found one chemical supplier here in Malawi that shows they have nitric acid, waiting to hear back. Their website shows they have “Nitric Acid 55%”. Is this the same percentage you use or close to it?
As for disposal of used nitric acid, any precaution and recommendations are welcome. While using it for bright dipping, do you use any sort of respirator or PPE?
With regards to the books, I don’t blame you for keeping on to those, we have a copy of The Complete Metalsmith in our workshop and I too wouldn’t let it go! Due to flight restrictions and cancellations at the moment, it looks like we won’t return stateside until May. We do have a friend that does our distribution that could receive them for us and hold on to them until we return though. Let me know if that is ok for you and I’ll private message you the information.
Thanks so much Judy!
Kyle, I really don’t recall what % my nitric acid is. I looked on the bottle I have, and it doesn’t say (BTW, the bottle is stored inside a plastic pail, which is sitting in a plastic dishpan, underneath a table where no one else goes! I think that 55% would be fine for jewelry use and would still need to be diluted. On Wikipedia, it says:
“Commercially available nitric acid is an azeotrope with water at a concentration of 68% HNO3. This solution has a boiling temperature of 120.5 °C at 1 atm. It is known as “concentrated nitric acid”. Pure concentrated nitric acid is a colourless liquid at room temperature.”
As for disposal of used HNO3, I can’t find my comments on it (at the moment), but will send anything useful, when I find it! I recommend your looking on Google for the safe disposal of used nitric acid. They talk there about further dilution with water and then flushing it down the drain(!), but I don’t know if the septic system(s) in Malawi would be up to that. I prefer going in the direction of neutralizing the acid with sodium bicarbonate. Buy some pH strips, in any case.
When using the bright-dip, yes, great care is needed. Nasty fumes come off the solution (even if you’re not using it — I store mine in a glass pie-plate, covered with a glass top, labeled “Warning: Nitric Acid"). It fumes more, when you put the brass into it — you do NOT want to breathe any of this!! I stand up-wind of a little fan, when I’m working (but I only do occasional small things, and I’m working in a large room with a high ceiling and in warm weather have windows open). For more frequent use, you would need to work out a better system — a hood for withdrawing fumes from soldering and bright-dipping would be good. Wearing rubber gloves may be helpful — getting the acid on your skin will turn it yellow, a sign that greater care needs to be taken! I do not use rubber gloves for this; I handle the jewelry piece with steel tweezers with pointed tips, to withdraw the piece of jewelry and to place it into my solution of sodium bicarbonate to neutralize the piece for further work. I have only once in about 40 years gotten a little patch of yellow skin. But I try to work rather slowly around the acid. My own diluted acid is presently quite weak, so I bought a little cheap timer to remind myself that, say, 3 minutes may be long enough for the jewelry to be sitting in it (sometimes it’s not—I really need to get around to adding a little more acid). If your diluted acid is fresh, its action works in seconds. I do not have a good suggestion for, say, a fume mask. I have one for hard-soldering, but don’t know if it’s appropriate for nitric acid fumes, and I didn’t have much luck on a quick check of Google.
I have another thought — I have several old notebooks of things I copied off of Orchid/Ganoksin in its early days (around 2000 and after), before it became limited mainly to gold-and silver-smiths who work for a living. Folks who worked with base metals for fun or profit used to have good discussions there. If you’d be interested in my sending along those 3-ring binders, they’re yours! A few sample topics (mostly only paragraphs long): citric acid; testing amber; using toothpaste to clean metal; drilling glass; jump ring maker; boric acid; Pripps flux; etching; home-made light box [and many, many more]. You could just throw out what you don’t find useful.
I would be happy to send any boxes to your friend who does distribution, to hold them for you.
All the best,
The non lab version of neutralizing acid is baking soda. Put your acid solution into a large preferably glass container like a bowl. Add the baking soda a little at a time. It will bubble a lot at first so go slow adding the BS. As it neutralizes, the bubbling will slow down. Swirl the bowl carefully to make sure it mixes up, or use the steel tweezer to mix it periodically. Once it no longer bubbles it will be fine. You could put it down a drain, but I’d let to evaporate the watery part off and take the dried remainder to a place that deals with chemical waste. There wont be much waste. Problem is older sewers probably even in Africa used copper. The acid if it was done be everyone would eventually (years) weaken some spots. It also depending on where the drain processes the waste. Err on the side of being responsible and treat it by not dumping it down the drain.
Thanks, Aggie! I seem to remember some discussion related to dumping the leftover waste (in small quantities) on soil where the nitrogen would be helpful. But of course I can’t find it at the moment…
WOW WOW WOW! You are an inspiration.
Now I have a question: what do you have in the way of air filters/protection for everyone’s lungs? I understand that electricity comes at a premium so having solar power is excellent. This is a huge issue right now for me because of the fires that have been burning here on the Left Coast. I don’t have any suggestions but just want to make sure that you have something to help your lungs stay healthy.
All sounds good, think I’ll get some and mess around with it to see if it will be realistic to use in our workshop. Some serious safety and proper handling safety would be in order! Also no worries about pouring it down the drain as there are no drains where we are located, so neutralizing and putting it onto some soil sounds like a good option. I’ll look into it further to ensure that’s not harmful for the soil/groundwater.
I’ll message you shortly about the books!
Thanks for the kind words!
As for protection, we provide dust masks + safety glasses for grinding/drilling operations. We don’t currently do any polishing as we are going for a matte/satin look that just requires steel wool at the moment so no compound dust flying around.
I do wonder about our soldering set up though because like you say electricity does come at a premium so a large ventilation system isn’t realistic. Our workshop is quite spacious and has quite a bit of cross breeze as well as an overhead fan we installed. Fortunately we aren’t battling gigantic wildfires on this side so fresh air is plentiful!
Is a cross breeze and overhead fan adequate in your opinion for our soldering station? What alternatives are there to duct work/large electric motors to suck out fumes?
The main culprit in soldering, as far as fumes go, is the flux you use. At soldering temperatures heated copper, brass, or silver don’t give off any significant vapor. If you’re using a simple flux, like borax and water, you don’t have to worry about soldering fumes at all.
Re polishing, I found that a bench grinder is the only way to get a mirror finish on brass, and I rarely do it, because, frankly the speed of those bench grinders is dangerous (can grab your jewelry and fling it away) and the buffing wheel throws off a lot of “stuff” that’s not good to breathe. (BTW, I have a wool buffing wheel and a polishing compound called White Diamond.) That’s why tumble-polishing is so much better — cleaner, quiet, and consumes almost no time! I have a Lortone tumbler that I have been using for over 30 years with no trouble whatsoever! Google “Judy Bjorkman tumble polishing” for a 1999 article I published in Lapidary Journal. If you are using steel shot as your polishing medium, be sure not to add too much, since the weight of the shot can make the tumbler struggle.
I’ll write more, later today.
Great news about the soldering fumes, I have been worrying about it quite a bit, but easy fix to switch to borax/water flux. Love simple solutions.
Going to try out using an abrasive media as well as steel shot in the rotary and see what results we come up with. @judyh was kind enough to get me a copy of her book so I’m diving into it and all it’s tumbling gloriousness!
Kyle - Be careful that the abrasive you choose to mix with steel doesn’t harm the steel. Silicon carbide is the main problem. As to the earlier comment about not using too much steel in your rotary, I wouldn’t worry - you have a large high capacity tumbler.
Thanks Judy. I did mean to use the same tumbler for the abrasive, then swap out to use steel shot inside. Any foreseeable issues with one tumbler for two different medias as long as I clean in between uses?
Here I am again! Regarding ventilation, the size of the facility and the cross breeze are good. However, I wonder if the overhead fan may serve to push evil fumes down where the workers are?? I’d recommend googling something like home-made ventilation systems and see if you could afford something like a hole in the wall with a fan in it to suck out fumes? [Also, a Shop-Vac would suck out fumes, etc.] And build a cheap and fireproof (brick?)soldering station in front of the fan. For HNO3 fumes, ditto on the hole in the wall with a fan installed to suck out fumes (probably you wouldn’t need to make this one fireproof). In our basement (when we used to live in Syracuse), I made a hole in the upper wall and attached a big clothes-dryer hose to it and rigged up something overhead at my soldering station, in addition to the little fan blowing gently behind me. I wish I could remember more of the details, but it was somewhat effective. Now I keep my acetylene tank inside a big plastic garbage can outside, and I do my soldering outdoors (when it’s not too cold and windy). These are just ideas for your consideration. If I come across more info., I’ll send it on.
I got the address of where to send the books, and will let you know when I do. As for the mailing cost, I’ll see how much it is. If it’s not too high, I could pay some/all of it myself. I’m just pleased to see the books going for a good use.
I am looking through my old Ganoksin notebooks — it is fun to recall the folks who were interested in the same things. I know you will find some of the remarks useful. Just throw out the rest.
All the best, Judy Bjorkman
Kyle and Ellen, FYI: I ran across the following comments from an old Ganoksin post on Fume Extraction:
“…I use a shop vac for fume extraction. I have a metal end for the intake hose which sits just above my brazing area (about 6”). Don’t want to burn down my garage…! I also have a hose connected to the exhaust, running to the great outdoors. I do not create jewelry on the same scale as the majority here…” —Tom Timms
If you already have a shop vac or can canabalize a standard vacuum or blower, that may do…here we have lots of range hoods which are thrown out and there are fans in them, ditto bathroom fans. However, if you can’t come up with something like this, there are inexpensive “in-line fans” available which fit seamlessly into round ductwork. They are available pretty cheap in 4 and 6 inch sizes and, here in the US, 4 inch is a typical size for flexible clothes dryer hose, so it is easy to rig one of these things. The in-line fans seem to go for about $15-$30. Hose, clamps and a fan and you are about done. Nice to have some kind of wide funnel to lay on the bench if using it for soldering or carrying away dust from polishing. For a chemical bench, one of the range hoods would work very well.
Managed to get ahold of some powdered borax. It came in small crystals that wouldn’t form into a paste so I mashed em up in a mortar and pestle to make a proper powder. This too formed into clumps when I added a bit of water. Is this normal with a DIY borax flux? If not, what am I missing?
Planning on looking into ductwork/fans next trip to the city. I have some nitric acid en route from the capital city so going to give it a go, I’ll let you know the results! Thanks again for the books and please do let me know about shipping charges if it is at all a bother for you, can’t thank you enough!
You have to add quite a bit of water to the borax. The borax needs to be ground with the water similar to the way you’d grind pigment with medium to make paint.
A regular mortar and pestle could work, but really it’s too deep a bowl to be convenient. A borax slate is a very shallow dish, which allows a small amount of borax to be ground with water and easily picked up on the brush.
Traditional slates are made of slate, duh. But anything that is very slightly abrasive and harder than the borax will work. A hard-fired, unglazed ceramic would likely work as a borax grinding dish, used with a pestle of the same material. Porcelain would be ideal, but that’s not likely available to potters in your area.
You could use the mortar and pestle to grind up larger batches of borax into a paste, then bottle it. You’d want to use a ceramic or glass mortar and pestle, not metal or wooden ones.
Great Idea about the unglazed ceramic, looking into getting a local potter to make a dish and pestle for me. Cheers Elliot!