Cleaned populated PCBs - Page 1
Forum section: electronics / repair

author: Foxxz
author_rank: Regular Contributor
timestamp: September 27, 2025, 04:21:30 pm
content: I bought some used PCIe FPGA boards. Upon receipt I immediately noticed that the boards had a distinct orange citrus smell and what appeared to be a light oily coating over them.I contacted the seller who said they "cleaned" the boards:Our specific formulation involves 1-Dodecene, Dimer (Hydrogenated), 3,5-Bis(1,1-Dimethylethyl)-4-hydroxy benzene propanoic acid branched alkyl ester, and Terpenes and Terpenoids, sweet orange-oil. The formula evaporates over time, as mentioned, and does not pose any threat to the card's operation.I've never encountered a PCB cleaner that left any residue and am concerned that the cleaner used will attract moisture or remain trapped under components and degrade them over time.Is anyone familiar with this cleaner or are these boards trashed?

author: Haenk
author_rank: Super Contributor
timestamp: September 28, 2025, 06:39:40 am
content: Quote from: Foxxz on September 27, 2025, 04:21:30 pmIf only those were used, they should vaporize. Maybe put them into an hot air oven at 60o Celsius, to speed that up. But I agree on that after cleaning, when selling, there should not be any residue left. Or rinse/clean with Isopropanol (if there are no component subject to flooding damage).

author: Paceguy
author_rank: Regular Contributor
timestamp: September 28, 2025, 09:17:26 am
content: Looks like those boards were cleaned with a orange infused cleaner that is available for household use and not rinsed properly. I would suggest riinsing them with warm demineralized water, followed by shots of compressed air to remove the water from under components and drying them in a low heat oven for a few hours.

author: Swake
author_rank: Frequent Contributor
timestamp: September 28, 2025, 07:12:57 pm
content: Something tells me that your supplier has no idea what they're doing or those cards have been stored in a dumpster like environment under layers of organic waste and rot.Ask them for the real commercial name of that cleaner instead of a list of some of the ingredients that are not relevant to cleaning PCB's.They have probably been washed with a soapy mixture of industrial detergent to clean whatever but PCB's.With that substance on it, the cards are not in a state that you can trust. Without knowing what it is and what was on them before they used that product you're only going to guess how safe it is to use. Is it going to cause extra oxidation over time? Is it conductive (even slightly)? Is there a biohazard etc etc.From diverse source son the net:1-DodeceneIt is an intermediate used in the production of lubricants and surfactants. used in detergent alcohols and alkyl aromaticsDimer (Hydrogenated)A hydrogenated dimer can act as an emulsion stabilizer, skin-conditioning agent, film-forming agent, or plasticizer in cleaning and personal care products, depending on its specific chemical composition3,5-Bis(1,1-Dimethylethyl)-4-hydroxy benzene propanoic acid branched alkyl esterBy preventing degradation, it helps maintain the effectiveness and stability of other chemicals in the cleaning product. Plastics: It is commonly used as an antioxidant in plastics to prevent yellowing and embrittlement. Lubricants: It also serves as an antioxidant and lubricant in other industrial applicationsTerpenes and terpenoidsact as natural solvents to break down grease and grime, possess powerful antimicrobial qualities to kill bacteria, fungus, and viruses, and serve as natural fragrances with aromatherapeutic properties. Natural Fragrances: They are responsible for the pleasant scents found in many cleaning products, providing a natural and uplifting fragrance as well as potential aromatherapeutic benefits. -> These things have NOTHING to do on a PCB.