Cleaning permanent marker from yellow fluke cases - Page 1
Forum section: electronics / testgear

author: PedroDaGr8
author_rank: Super Contributor
timestamp: May 16, 2014, 10:04:26 pm
content: Removing permanent marker from yellow fluke cases. I know many of us have an issue with it. As a chemist I have access to quite a few solvents so I did a test on a heavily abused Fluke here at work.I tried a few solvents to remove the sharpie:Reagent grade Methanol: Fades the sharpie, about 30-60% left, no transfer of yellow from the holster to the cloth.Chloroform: Same as methanol1-butanol: performance similar to methanol, offensive odor, gives me a slight headache.Pure Acetone: 100% removal of sharpie but heavy transfer of yellow from the holster to the cloth. Appears to actually degrade the holster a bit. If you have a textured case it will make the case shiny by removing the texturing.DMSO: 95-99% removal of the sharpie, seems to attack the holster significantly less, especially initially. Upon sustained buffing the rubber turns crumbly, which stops after the DMSO has FULLY evaporated.DMF: Fades it a bit but also smears the sharpie into the rubber. Avoid.Acetonitrile: Fades sharpie, minor yellow transfer. Similar to methanol.If it was me, I would try a short burst of DMSO to remove the 90+%. Not long enough that the yellow starts crumbiling. Followed by a 100% Acetone cleaning to get the rest. Limiting the exposure to the acetone as well. You could also skip straight to acetone cleaning. Lastly, followed by a wipe down with MeOH to remove any solvent residues. Note that I tried nail polish remover with less than optimal results. It must be pure acetone, which is cheap to get on Amazon (so is pure DMSO) but it might get you put on a watch list since it can be used to make acetone peroxide. In conclusion there is no IDEAL magic solvent but there are a few that can work in a pinch.

author: Fank1
author_rank: Regular Contributor
timestamp: May 16, 2014, 10:15:16 pm
content: I've used denatured alcohol with good results.

author: IanB
author_rank: Super Contributor
timestamp: May 16, 2014, 10:19:03 pm
content: Quote from: PedroDaGr8 on May 16, 2014, 10:04:26 pmOn this subject I recently obtained a bottle of pure acetone from CVS. It was sold as plain, simple nail polish remover "without scents or other additives".When removing ink and stains, the best technique is repeated applications using a dabbing motion. Apply solvent from a wet cloth or paper towel, leave it to soak for a short time, then dab it off with several applications of dry paper towel or blotting paper, pressing firmly without rubbing. This minimizes the damage to the object being cleaned. Patience is key.You could also try a bleach like peroxide or hypochlorite to see if it can erase the residual ink color.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: May 16, 2014, 10:19:46 pm
content: Sorry forgot to attach images.Before:After:

author: PedroDaGr8
author_rank: Super Contributor
timestamp: May 16, 2014, 10:27:48 pm
content: Quote from: Fank1 on May 16, 2014, 10:15:16 pmConsidering what I experienced with methanol and butanol. It's likely one of the denaturants doing the cleaning. And therein lies the problem. There is no standard set of denaturants.

author: 8086
author_rank: Super Contributor
timestamp: May 17, 2014, 09:08:14 am
content: Quote from: PedroDaGr8 on May 16, 2014, 10:27:48 pmIPA works very well on permanent ink.

author: TMM
author_rank: Frequent Contributor
timestamp: May 17, 2014, 01:12:29 pm
content: +1 for IPA. I have also used gel hand sanitizer (70% ethanol w/w) to clean permanent marker off plastics and metals with excellent results.

author: true
author_rank: Frequent Contributor
timestamp: May 17, 2014, 03:21:18 pm
content: IPA also doesn't do that great with Fluke holsters - it will start attacking the yellow and can turn it shiny after a while during cleaning, and after evaporating the case may have a different feel where it was cleaned, almost a tacky smoothness (whether it is physical in that some texture is removed or some change happens I don't know).Brief exposure to IPA works fine so after some light physical cleaning I'll usually use IPA to go after the rest. If the ink is new or light enough that usually takes care of it.

author: TheAmmoniacal
author_rank: Unknown
timestamp: May 17, 2014, 04:41:59 pm
content: I would recommend ethyl acetate, the solvent found in "acetone free nail polish remover", and it smells great!

author: linux-works
author_rank: Super Contributor
timestamp: May 17, 2014, 04:49:37 pm
content: how about on steel or brushed aluminum? I have a tektronix case (1101 power supply) with some ugly sharpie marking on the front panel. I don't want to damage the metal or the finish. has anyone had any luck with removing marker from this kind of metal?

author: krivx
author_rank: Frequent Contributor
timestamp: May 17, 2014, 05:20:38 pm
content: Steel or aluminium should take solvents just fine. Try IPA.

author: IanB
author_rank: Super Contributor
timestamp: May 17, 2014, 05:24:24 pm
content: Quote from: linux-works on May 17, 2014, 04:49:37 pmOne trick I recently learned to remove permanent marker from hard surfaces is to use a dry-erase pen. Just scribble over the permanent marker with the dry-erase pen, wipe off with a paper towel, and repeat until the permanent ink is gone. But this will only work on hard, non-porous surfaces like metal and glass.

author: SeanB
author_rank: Super Contributor
timestamp: May 17, 2014, 05:29:17 pm
content: With coloured anodised aluminium you can use acetone, as the dye is held captive under the surface. No scrubbing, just dabbing with acetone, or Xylene or toulene to remove the marker. The dry wipe marker trick also works for some markers, but really depends on what the original marker solvent is. I have some MEK solvent that will remove almost any ink or marker pretty well, along with dissolving most plastics.

author: electronics man
author_rank: Frequent Contributor
timestamp: May 17, 2014, 05:30:24 pm
content: Why don't you use the DMSO then diluted acetone or IPA

author: iDevice
author_rank: Regular Contributor
timestamp: May 20, 2014, 07:19:27 pm
content: Could someone explain what DMSO stands for ?

author: Fsck
author_rank: Super Contributor
timestamp: May 20, 2014, 07:22:56 pm
content: Quote from: iDevice on May 20, 2014, 07:19:27 pmdimethyl sulfoxide, but google could've told you that.

author: robrenz
author_rank: Super Contributor
timestamp: May 20, 2014, 08:01:35 pm
content: Is your Google broken?

author: iDevice
author_rank: Regular Contributor
timestamp: May 22, 2014, 09:27:05 pm
content: Thanks.Was tired yesterday, didn't think it was so obvious to find.College chemistry courses are a bit rusty after 35 years...Now, what is Google btw ? ...

author: FrankenPC
author_rank: Unknown
timestamp: May 22, 2014, 10:02:13 pm
content: Quote from: marmad on May 22, 2014, 09:53:19 pmSo, you just take a cloth, put some paraffin oil on it and rub away the sharpie marks? That easy?

author: marmad
author_rank: Super Contributor
timestamp: May 22, 2014, 10:09:32 pm
content: Quote from: FrankenPC on May 22, 2014, 10:02:13 pmI deleted my comment because I thought the OP was talking about typical yellow PLASTIC instrument case (from his opening sentence) - and not the specific yellow RUBBER holster (although he made that clear later - which I retroactively realized). The paraffin oil definitely works on plastic cases - but I'm not so sure about rubber - I would have to test it - but I'm not around my Fluke at the moment.

author: IanB
author_rank: Super Contributor
timestamp: May 22, 2014, 10:11:04 pm
content: Quote from: FrankenPC on May 22, 2014, 10:02:13 pmIn general, don't rub, use a dabbing motion. Dab on the solvent with a wet cloth, soak it off with a dry towel. Repeat until ink is removed.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: May 22, 2014, 11:31:43 pm
content: Getting sharpie off of glass, hard plastic and other non-porous surfaces is a piece of cake. Methanol, acetone and a variety of other solvents will do it no problem. The issue is with the highly porous rubber that fluke uses. Shape removal is much harder with this rubber.

author: marmad
author_rank: Super Contributor
timestamp: May 22, 2014, 11:35:45 pm
content: Quote from: PedroDaGr8 on May 22, 2014, 11:31:43 pmBut I wouldneveruse acetone on most plastic - bad mistake.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: May 23, 2014, 12:02:16 am
content: IQuote from: marmad on May 22, 2014, 11:35:45 pmMethanol is the safest of the bunch but I'd agree about avoiding them if you don't know what type of plastic you are dealing with. Many plastics can handle the above just fine but many can't (transparent plastics like polycarbonate are particularly sensitive). If you don't know which you have its a crap shoot that isn't worth it.

author: marmad
author_rank: Super Contributor
timestamp: May 23, 2014, 12:09:09 am
content: Quote from: PedroDaGr8 on May 23, 2014, 12:02:16 amI personally think Methanol is almost worthless for markers and paint on most plastics. I don't know how much testing you've done (I've done a lot - I refurbish old analog synthesizers and other musical gear - much of it plastic), but it would be impossible to completely remove the permanent marker as in the attached two photos with Methanol (and Acetone would just eat away the plastic).What usually works best for most plastics are the light petroleum distillates: mineral oil (which is used to remove excess ink from engraved plastic buttons and switches), liquid paraffins, and petroleum spirits.

author: Stonent
author_rank: Super Contributor
timestamp: May 23, 2014, 12:21:49 am
content: I've found Naptha removes most things off of plastics. I think I've used it on marker, but not 100% sure, but it certainly does a good job on removing stickers.

author: edavid
author_rank: Super Contributor
timestamp: May 24, 2014, 06:02:20 am
content: Pedro, would it be possible for you to identify the solvent used in some test markers, or at least in a Sharpie?

author: IanB
author_rank: Super Contributor
timestamp: May 24, 2014, 06:15:05 am
content: The solvent used in Sharpie permanent markers is a mix of higher alcohols: n-propanol, n-butanol and diacetone alcohol (4-Hydroxy-4-methyl-pentan-2-one).Note that n-propanol, or n-propyl alcohol, is similar to isopropyl alcohol, so isopropyl alcohol might be expected to work as a solvent for removing Sharpie ink.

author: mzacharias
author_rank: Frequent Contributor
timestamp: May 24, 2014, 12:37:32 pm
content: Just a thought - and I know it's scary, but the other day I tried cleaning some OLD sharpie type markings off an aluminum heat sink. Using 91% isopropyl alcohol left a very visible "ghost" of the old markings.Reasoning that a new Sharpie used the same solvents, I marked over the old markings with fresh ink, THEN cleaned using the alcohol. Not a trace remained.If this Fluke holster were mine, I might try this in a very limited way, tracing over a small part then trying to clean it again.

author: G7PSK
author_rank: Super Contributor
timestamp: May 24, 2014, 02:21:07 pm
content: I use T-Cut it also polishes out the scratches on screens.