Electronics workbench coating, what would you recommend? - Page 1
Forum section: electronics / general

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: May 08, 2023, 10:13:58 pm
content: There's a similar thread here:https://www.eevblog.com/forum/chat/electronics-workbench-material-recommendations/But my case is a bit different.I wanted something that is non-conductive, non-flammable, and not concrete or something very permanent. It should be like a mat or something that can be taken up and placed down. Preferably, not expensive as I'm just a hobbyist. It doesn't have to be any size, I'll cut or overlap it as needed.Thanks!PS: I asked my parents. Mom recommended aluminum foil. I'm still laughing.

author: thm_w
author_rank: Super Contributor
timestamp: May 08, 2023, 10:39:18 pm
content: Normally people would buy a high temp ESD mat but don't know if thats in your budget as you have not posted one:https://www.eevblog.com/forum/reviews/where-to-buy-esd-mat/The cheaper option is a silicone mat, you can get a baking mat or one specific to electronics:https://www.homedepot.com/p/Weller-Soldering-Work-Station-Mat-WLACCWSM2-02/314638551But its smaller, so would only cover a portion of the bench.

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: May 08, 2023, 11:20:33 pm
content: Interesting that none of the datasheets I consulted from digikey, one of each material, didn't mention flame/spark resistance, which is one of the requirements I have. I expect I'm not the only person in the world working with electronics that might cause a spark to happen, or might have a piece of equipment that would temporarily catch on fire.Personally, after thinking about it, I'm of the opinion that silicone rubber would be a good choice. Unlike vinyl or PVC, it will not emit any toxic fumes if exposed to sparks or flame.It's unclear to me if an Elastomer, Polymer, or Laminate has suitable resistance to sparks/flame.

author: EPAIII
author_rank: Super Contributor
timestamp: May 08, 2023, 11:24:32 pm
content: I have had ESD mats at several of the companies where I have worked. When I was setting up shops I did not worry about ESD and things worked just as well. Frankly, I don't think it is really needed if you have a small, grounded surface you can touch before handling static sensitive parts. And a conductive surface on the bench top, that is grounded can be problematic when working with breadboards or circuits tacked together in mid air. It can also provide a ground path if you come in contact with an energized circuit so it can be a shock hazard. I don't really like using ESD mats on any workbenches.As for sparks and fire, I have worked in electronics for over 45 years. Much of that time I worked with high power TV and radio transmitters. I was in in college labs and home workshops for at least ten more years before and after that professional career, so about 65 years total. I have seen exactly ONE electrical fire which was in a tube type, professional, color monitor. It was confined to the inside of the steel outer enclosure so it did no damage to anything around it and it went out when power was turned off. On ONE other occasion I was close to an electrolytic capacitor that more or less erupted in my face. No sparks or fire and I was lucky that a steel member was between it and my eyes. Oh, and ONCE I accidentally placed a screw driver across a 24 VDC circuit that was capable of many Amps. The screw driver tip was vaporized and sparks did fly. But it was real brief and there was zero chance of a fire. Perhaps these few incidents could have ignited something like news paper, but not even a bare wood bench would have been at risk.But in all of my 65+ years, that is about the sum total of sparks and fire that I have seen. This is real life, not Hollywood. I also do metal work and have shop grinders that can throw a much more impressive shower of sparks than any electronic device that I or you will ever work with. Still, as long as they don't hit an open container of gasoline, they do no harm. If you are reasonably careful, I don't really think you need to worry too much about sparks or fire.I have set up two electronic benches in my home office and garage shops. The one here in the office is just an inexpensive, folding table as sold in home supply centers like Lowes or Home Depot. I did not add anything to the top. In the garage shop I installed an oak plywood top with solid oak borders on top of two purchased cabinets for drawer and shelf storage below. The top is finished with several coats of Water Based Polyurethane Wood Finish. I have used this on other benches and it is a durable surface, but not scratch proof. I have purchased what is called aself healing matfor the top. These are available at hardware and hobby stores among other places. It is almost a perfect for the custom sized top so I got lucky there. I need to clear the top of the bench to install it.NOTE: Self healing mats are intended for cutting thin things like paper, cardboard, plastic sheet, etc with hobby (Xacto) or similar knives. The knife only penetrates a short distance into them and they show no signs of damage after many cuts. In addition, they usually have an X-Y grid of lines with dimensions along the edges to serve as cutting guides. I often make use of that grid. And they are NOT conductive. IMHO, they make excellent tops for work benches.https://www.google.com/search?client=firefox-b-1-d&q=self+healing+mats

author: dobsonr741
author_rank: Frequent Contributor
timestamp: May 09, 2023, 01:47:53 am
content: Local Daiso has great cooking silicon mats, if you are in this neck of the woods.https://daisous.comOtherwise I have a white glass desk, love it, can not leave ugly burnt solder marks and cleans great with IPA. I use silicon mats (Daiso ones) if I want no slip. I also have a proper blue antistatic mat, collecting dust, never use it. I hate when soldering on it messing it up. Also gets dull after cleaning flux residues with IPA.

author: Oilngas
author_rank: Contributor
timestamp: May 09, 2023, 02:37:17 am
content: I have an 11X14 inch glass tray from an old microwave oven that I place on my work surface when soldering. Non-conductive, nonflammable and solder drips scrape right off.

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: May 09, 2023, 03:17:08 am
content: Quote from: EPAIII on May 08, 2023, 11:24:32 pmWell, I'm a bit ashamed to admit it, but I accidentally grabbed a boost convertor instead of a buck convertor one day. I hooked my DMM to read the voltage and kept adjusting it until the boost convertor caught fire. It wasn't alight for long (5s or less), but it did alert me that things don't always fail in a safe manner.Also, less than ideally safe is the Li-Ion drill battery changer I have. Every time I plug it in, I can hear a spark inside of the outlet. Although I've heard this happening before, it's always been rare with various other pieces of electronic equipment.So it is possible, it's just not a normal thing to encounter and the desk I intend to operate on is a nice wooden one. I'd rather not ruin it.

author: Infraviolet
author_rank: Super Contributor
timestamp: May 09, 2023, 04:07:27 am
content: As the sparks and fire argument goes, even a hot soldering iron tip in prolonged contact with a "wooden"* surface won't actually cause an ignition but rather a localised charring. I wouldn't worry too much about things on an electronics bench catching fire, just so long as you don't leave pools of solvents on it.*this may well not be the case for all types of wood

author: Colt45
author_rank: Contributor
timestamp: May 09, 2023, 05:10:59 am
content: The hardware stores here sell quarter sheets of formica for almost nothing (presumably salvaged from damaged full sheets). You could just stick the corners down with double sided tape and replace it if it gets too beat up.It wipes off nice and shouldn't burn great.

author: jonpaul
author_rank: Super Contributor
timestamp: May 09, 2023, 06:45:12 am
content: We have used formica covered wood benches since 1980s.Working on HV, SMPS, EBU up to 75 kV and several KW, we had no issues with ESD nor fire.The worst was some burn marks from overheated load R or misplaced soldering irons....A 6 mm masonite sheet is fine as a temporary bench surface, cheap and easily replaced.For ESD, put metal sheet or Al foil , 1 M R to earth gr.Cover metal with masonite or formica.Jon

author: tooki
author_rank: Super Contributor
timestamp: May 09, 2023, 07:12:14 am
content: Quote from: EPAIII on May 08, 2023, 11:24:32 pmThat is bad advice.Most ESD damage goes undetected at the time, so your claim that it’s “not really needed” is impossible to prove.An ESD mat has enough resistance to pose no shock hazard. (That high resistance also slows down ESD events so as to reduce the current.) 1 megohm is common. Also, ESD mats are multilayer, with the surface layer having much higher resistance than the bottom layer.And what problems do you think it causes for breadboards?

author: jwet
author_rank: Frequent Contributor
timestamp: May 09, 2023, 07:37:10 am
content: I'm ++1 for Formica. Its an amazing material and makes a great bench. The only thing you can't do on it to solder directly on it- but why? I've built several benches with it over the years and its a great surface. It will easily adhere to anything like MDF, Plywood, etc. with contact cement and make a very flat working surface. Its extremely tough. I use small silicone mats or just a plywood blocks to solder on but everything else the Formica can take with ease- great stuff. I've had a few things blow up on my bench over the years I'm proud to say but they don't leave any lasting marks. I routinely get all the little bits of wire and solder off with a credit card or similar and scrape them into a trash can. I then clean it with 409 or Windex and once in while I'll use a kitchen cleanser on it- I don't grind it in, it will get rid of more embedded crud. I like flat white but I've used almond before because it was free.

author: Berni
author_rank: Super Contributor
timestamp: May 09, 2023, 10:25:37 am
content: No coating will make wood into a temperature resistant or flame proof surface!Then again not like you need it to be that resistant. Giving it a bump with a soldering iron won't really cause that much significant damage. You should not really use hot air directly on it in in the first place (I recommend using PCBite kits, they are made out of metal and come with a stainless steel plate). Wood is not prone to ESD either. A workbench surface gets a scuff here or there eventually, just use sacrificial protective mats when doing more violent things on it (like cutting, heating, abrasion, hammering..etc)If you do want a longer lasting surface on your wood desk, i would recommend using an epoxy coating. They are resistant to a lot of things, especially solvents (things used to clean PCBs can eat some coatings) and it makes for a smooth sealed surface that is easily cleaned with simply a damp cloth.Another easy way out is to just buy a kitchen counter and use that as the desk surface. That stuff is resistant to a lot of things.

author: rdl
author_rank: Super Contributor
timestamp: May 09, 2023, 06:56:23 pm
content: The best bench top I had I ever had was stainless steel with wood backing. The second best was some kind of epoxy composite stuff. Two inches thick and very heavy. I worked in chemistry labs though.

author: thm_w
author_rank: Super Contributor
timestamp: May 09, 2023, 08:30:52 pm
content: Quote from: rdl on May 09, 2023, 06:56:23 pmStainless would be great for chemistry, but its terrible for electronics. You'd constantly be shorting stuff out and having to put a sheet of insulation on top of it.Stainless with a big rubber ESD mat on top would probably be good though. Earth the bench and 99% of your ESD concerns are gone.

author: sokoloff
author_rank: Super Contributor
timestamp: May 09, 2023, 09:14:34 pm
content: Quote from: Berni on May 09, 2023, 10:25:37 amThat kitchen counter is quite likely to be wood with a plastic laminate on it.

author: Xena E
author_rank: Frequent Contributor
timestamp: May 09, 2023, 11:09:57 pm
content: 0.015" Nomex sheet.Guys from the windings department covered my bench with it when one of them heard me complain about the state of the surface when I inherited it. I basically have 4 m² to use as a soldering iron stand... you can't burn it with an iron: it's physically tough too.

author: Berni
author_rank: Super Contributor
timestamp: May 10, 2023, 05:11:07 am
content: Quote from: sokoloff on May 09, 2023, 09:14:34 pmYep exactly, but the laminate used there is pretty tough stuff since it is designed to have sharp objects thrown around on it, hot pots placed down on it. It is also easily cleaned and has a texture that hides scratches.At the same time it is pretty cheap from a generic hardware store while requiring no finishing applied to it, just add legs and you got a workbench. It is not exactly indestructible but for the cost and effort it is pretty good.Metal is most definitely a bad idea for an electronics workbench surface, makes it way too easy to short things or could even be a safety hazard when high voltages are involved. If you are going to cover the surface with something just get a ESD mat.

author: Infraviolet
author_rank: Super Contributor
timestamp: May 10, 2023, 05:35:44 am
content: "just add legs and you got a workbench"For an electronics workbench, that is to say something you won't be using to mount vices against which you'll hammer, saw or use power tools, a typical "wood" topped office desk, or several together is probably going to be easier than building a custom bench. If you really need an alternative surface then fit an extra layer of the extra material atop a typical office desk rather than build the whole thing from scratch. An electronics bench doesn't need to cope with loads any greater than you leaning on it the way you'd lean on a desk where a computer keyboard was, nor to damp out vibrations from vigourous tool use.

author: tggzzz
author_rank: Super Contributor
timestamp: May 10, 2023, 08:09:15 am
content: Quote from: Berni on May 10, 2023, 05:11:07 amPrecisely.Last week I made such a bench myself:132*60*2.5cm laminate: cost £0, since it was an offcut being given away on a website for such things (freecycle)height adjustiblelegs (Ikea Olov) that I had in the garage. No mounting plates, but Ikea kindly sent them free: cost £0ESD mat from previous worktable: cost £0 (this time)If I decide I don't like it, I'm not going to worry about the purchase costQuote from: Infraviolet on May 10, 2023, 05:35:44 amNot quite. It also has to support whatever equipment you are using at the time. An affordable decent spectrum analyser or a decent KVD or similar won't be light. Typically fleabay sales mark them as "collection only"

author: Berni
author_rank: Super Contributor
timestamp: May 10, 2023, 09:36:17 am
content: Yes office desks also make perfectly usable electronics workbenches, tho it is good to get a decent quality ones since the cheep flatpack desks you get these days are pretty flimsy (thin, low density particle board).Building your own is more of a reason when you have requirements that don't fit available desks. Like for mine i wanted it more workbench height rather than desk height and i wanted a 3m wide desk without having legs get in the way, also wanted it deep because of equipment. Nothing out there fit that, so i built my own. While i was at it i also gave it an equipment shelf in the back so that it keeps my test gear lifted a bit out of the way.And yeah don't underestimate the weight of boat anchors from the 80s, you can have a single spectrum analyzer weigh over 50kg. They certainly don't need to be as sturdy as a workshop bench with a vice, but for sure it has to pass the Matthias Wandel furniture test.