MG Chemicals 410-1KG Ammonium Persulphate Copper Etchant, 1 Kg Solid Crystals Bottle

This is significantly easier to use than ferric chloride, since this stuff is transparent, turns blue as it's used up and doesn't stain half my world yellow-brown. I etch at 50C, which tends to make the ammonium sulfate break down, but it gets the job done quickly and minimizes overetching and undercutting. Shelf life is an issue. I don't make pc boards very often, and my etchant tends to lose its potency after a few weeks in the bottle. I now make only a small batch (125 grams per 500 ml) and use a small (120 x 160 mm) glass tray to etch boards horizontally. I put the board on a perforated PVC shelf and agitate the solution with a magnetic stirrer. Works very well. The price has gone up 23% in 3 years, but the price with Prime shipping is hard to beat. I use a variety of MG Chemical products and have found them all to be consistently high quality.

Needs to be heated to work, but is clear so you can see the etching progress.

Am a copper artist and use this for cleaning copper before applying a patina-I have about 40 different chemicals I use and create my own patina formulas. Been using this stuff for years-love it! No problems with the supplier.

If you use the product with an etching tank with a heater and a sparging pump for an agitation bubbler, I found an extremely high quality etch in only 15 minutes. I see the solution turning bluer with each etch-don’t really know what the maximum yield or how many p.c.b.’s one can expect to make with one bottle, but I was able to get 4 double sided 6”X6” boards completed without any problems. Maybe I’ll have 6 boards ready to go for the next project. I’m not really sure how much dissolved copper can exist in the solution and still work effectively. No one is reporting on this issue. If you have your traces surrounded by ground planes, maybe you could etch boards all day.

Works very well and came earlier than expected

This is the best product for its intended use. Attractively priced, and properly shipped by the seller.

Nice to be able to see the board as it's being etched.

Yes

Good quantity for the price.

For over 20 years I have been using sodium persulfate to etch brass, but lately it has been almost impossible to find. I decided to purchase this copper etchant just to see if it would work on brass. As you can see in the photo, I etch through the brass to make model parts. This copper etchant worked even better and faster than my usual etchant. It is just fantastic! And knowing I can buy this on Amazon makes my life so much better. If you are looking for a brass etchant to make parts, I highly recommend you give this product a shot!

I tried this product a few days ago. It etches fine and I will buy it again when needed

I bought this to try as an alternative to the normal ferric chloride etchant. On the plus side, the fact that the solution is clear means you can see the board as it is being etched. Etching seems to take a lot longer than with ferric chloride (though dissolving these crystals in water is an endothermic process, so it may have been my etch solution was somewhat colder than ambient room temperature, thus extending the etching time). Regardless, the next time I try to etch a board with this, I'll probably try a little bit of gentle warming to speed the process up. It's not quite as messy as ferric chloride, though in terms of chemical hazard it is probably on a par - in some regards the messiness of ferric chloride possibly tends to make you take a bit more care with it. Overall, I mostly happy with the product, though it probably suits a heated bubble etching tank better than hand etching in a tray. The solution slowly decomposes on standing, so it's probably best to only make up as much as you need.