Soldering--DIY Rosin Flux Experiment (4K)

Rosin flux is for electronics and copper, gold, and silver. (NEVER use acid flux on electronics. You WILL regret it. It's a mistake that keeps on giving.)
Disclaimer: This is an experiment and is not time tested (I've been soldering since 1962) so use at your own risk. Some solvents can damage plastics and other. Most solvents are toxic to breath or by contact, take proper precautions. Soldering carries the risk of burns, fire, etc. Learn first or don't do it. IPA (isopropyl alcohol or isopropanol) is flammable and poisonous. Use proper precautions.
NOTE: The commercial flux in the video is NOT rosin based, I just needed a working sample to compare the prepared flux to for ability to flux and cleanliness.
PER THE INTERNET ======================================
Ratio is 1g rosin to 10 ml alcohol (99% IPA, better if not denatured)
COMMERCIAL FLUX =====================================
Is 2% solids.
DATA =================================================
Isopropyl alcohol weighs 0.78509 gram / cc
10 cc would be 7.85 grams
2% of 7.85 grams is 0.157 grams so 1 gram is about 6x too much

[@juanignaciocarrano860]

I clearly overdid mine. It is saturated with rosin, thick as honey. The commercial stuff clearly has some acid or something as you can see in 15:02 that it has removed the oxide from the copper.

[@tsbrownie]

Yes. I found one that uses adipic acid, something I have never heard of before. From what I found it's a weak organic acid.

[@juanignaciocarrano860]

@@tsbrownie adipic seems to be used as food additive, so it must be relatively safe I guess

[@tsbrownie]

@juanignaciocarrano860 Yeah really, just because they put it in food may not mean much about safety. 😒 Anyway, I think I'm going to try it.

[@phizc]

​@@tsbrownieadipic acid is found in beets and sugar cane. Whether they use food grade adipic acid in the flux is a different question, of course 😅.

[@jdk8787]

Interesting. I would have liked to see soldering on the board without any, just to compare.

[@tsbrownie]

Good point. Never thought about that.

[@adnacraigo6590]

You went into an area I have wondered about on this one.

[@tsbrownie]

I've got glycerin on order. We shall see what that does. I have a feeling that there is a secret ingredient in the commercial fluxes.

[@perttisalonen850]

Good test! The 2% flux solution seemed to be rhe right one for soldering. Where did you get the ball-point pen which you filled with the fit flux?

[@tsbrownie]

It's called a paint pen. Ordered it online. I think it was an art supply store, but I can't remember for sure.

[@t1d100]

Thank you. This is an area of great investigation, personal preference and debate. 1) The DIY rosin is not "no-clean." The rosin is aggressive and will damage things, down-the-road, if not absolutely completely removed. 2) It looked like the larger puddles of rosin/alcohol were cooling the PCB, via evaporation, and slowing down the reflow. I had not thought of that as a factor, before, and I found it an interesting consideration. 3) I think that one of the ingredients in the paste type rosins is nothing more than petroleum jelly. But, I am not sure. Cheers.

[@tsbrownie]

If you look closely, you can see the commercial pool cleaned the copper more aggressively and in 4K you can see it bubbling. What they add is going to require more investigation. As for petroleum jelly, I have never heard of that and as a general rule you don't want oils of any type on your workpiece, solder or iron. Update: I found lots of people claiming to use petroleum jelly, but no videos. That would leave a mess to clean off. I once put a dab of that stuff on an outdoor screen window as an experiment, and it took 11 years for it to disappear!

[@johnr1256]

@@tsbrownie Hello, nice test, my comercial soldering flux have list of ingredients, and one of ingredients is hydrofluoric acid. of course with resin and alcohol. Maybe what you have there is also some kind of acid - they dont evaporate much and have oily feel, and also they are active all the time so you need to clean them thoroughly. Resin acts as acid only when heated above 200C. so it does not damage anything when not heated, only looks ugly.

[@tsbrownie]

@@johnr1256 Interesting. Thank you.

[@LockRocker]

I wonder if this will help stop all the violins in my community. When I was a kid we were just happy to solder and build stuff. I'm going to harvest some raw build up off my white pine that needs to come down in the spring and give that a go. I wonder if there's any adverse effects of xantham gum to thicken it up, i use that in hot sauce, lol. Maybe a good focus is how to clean it up easily, since many recommend cleaning up the no clean anyway. Next time try chipping at the tests for adhesion impressions.

[@tsbrownie]

@LockRocker I've got another formula to try that is supposed to be much better. Won't stop violins though.

[@ChrisModjeska]

I looked up kester-951 and it claims to be a non-rosin flux FYI.

[@tsbrownie]

True. It's something like 3 alcohols, a thinner, and an organic acid. I was using it as a comparison. I should have said that.

[@williamemerson1799]

Made some a while back using pine sap right off the tree. Had to be strained of course. 2 parts 91% IPA, 1 part pine sap, by weight. Worked great, wasn't runny but thickened up in the container in short order. Could've used a lot more IPA.

[@Christian-lh7ux]

Nice test. I have to try it bc flux pens are indeed expensive af 😅 Do you have a dosage for the glycerine?

[@tsbrownie]

I'm going to try 1% and adjust as needed.

[@franzliszt3195]

Super duper!@@tsbrownie

[@Christian-lh7ux]

@@tsbrownie let us know ;)

[@tsbrownie]

@@Christian-lh7ux I should make a how-to when I get the final version.

[@Christian-lh7ux]

@@tsbrownie Very good idea 😁👍

[@JustinRand-w6o]

It wouldn’t be sticky and still have higher properties and what you’re trying to do probably or it would be stickier, but if you heat it up, put it in the Pyrex dish and cook the alcohol off of it

[@rubenmejia4881]

I would like you to repeat this experiment and use solid wire solder to ensure that the core flux doesnt tamper with the results. Excellent video nun the less. I've been trying and wondering what would be the best way to do this, and surely your calculation seems a lot more accurate on the revision. Have you considered making tacky paste flux as well?

[@tsbrownie]

I have not considered paste. I have found a better flux formula, but one on the ingredients has been hard to find at a good price.

[@rubenmejia4881]

@tsbrownie is that right? Care to share? I was reading well trying to get ahold of data sheets from manufacturers, and the way you do it seems right, but they also have proprietary mixes and hid ingredients as well from what I've noticed. I tried asking some, but they won't talk, and I wouldn't expect them to either, but it would be nice to find a good home solution. I applaud you for your attempt and documenting it for all of us.

[@tsbrownie]

@rubenmejia4881 One secret is to look up the poison / EPA declaration sheets. The ingredient that is being stubborn is adipic acid and it's in a mix of alcohols.

[@rubenmejia4881]

Yes that's what I was referring to commonly called safety data sheets adipic is one I've also seen citric acid and malic acid used as well I'm going to try with citric since it's easy to get a hold of.

[@clytle374]

The MG chemicals RA flux i use is brown and super sticky. I never expected rosin to be clear

[@JustinRand-w6o]

What about a biscuit joint needle? I bet it locks the pan. I haven’t seen this but could use the biscuit joint needle but I think it be a good idea to filter the raw in an alcohol and burn the alcohol off then do your process again kind of like distilling

[@tsbrownie]

I found a mix that might be better. I've ordered the stuff. We shall see.

[@JustinRand-w6o]

Cool , nice video,thank your for answering your guest .🔒

[@JustinRand-w6o]

Filter the rosin in in the syringe, put a piece of cotton, put the Rozen in the back of the baby syringe, then push it through to the needle canister then it’ll purify it then add heat to burn the alcohol off and you let me left with purified Rozen

[@robertwebb5586]

I make my own and put it in paint pens...