Refurbishing a Metcal workstand - Page 1
Forum section: electronics / general

author: MaximRecoil
author_rank: Regular Contributor
timestamp: December 08, 2016, 12:57:41 am
content: I didn't think to take a good picture before I started; I only have an older picture I took for a different reason:That picture doesn't really show the extent of the corrosion. The sponge area was covered with whitish corrosion byproducts, and it had a death grip on the die-cast zinc (AKA: pot metal). I normally remove corrosion byproducts with Bar Keepers Friend (main active ingredient: oxalic acid). For example, it removes similar looking corrosion byproducts from aluminum alloy wheels fairly quickly, but it wasn't having much of an effect on this stuff. Steel wool and a steel wire brush were pretty much ineffective as well. So I gave it a 24-hour bath in a solution of water and pure oxalic acid, and that fixed its wagon.Next I needed to remove the powder coating. I'd already removed all of the powder coating that was loose due to being separated from the metal by corrosion, but the rest of it wasn't going to come off easily. Then I remembered that I have some Goof Off Graffiti Remover, and a long time ago I discovered that it melts through some types of plastic (Lexan  for example). Given that powder coating is just a type of plastic, I gave it a try, and it did indeed melt it. However, it evaporates too quickly to let it soak long enough to completely melt through it, so I had to spray some on and scrub with a wire brush, and repeat until it was all gone:You can see the damage from the corrosion in and around the sponge area, but the damage isn't even close to being deep enough to cause any structural issues. The rest of the metal was pristine:Here it is with a couple of coats of primer:I want to finish it with Rust-Oleum textured black paint, which does a pretty good job of approximating the appearance of typical textured powder coating, but of course, no place in town had it. They had plenty of cans of various types of Rust-Oleum, but not the textured type I was looking for. So I ordered some online yesterday. I'll post a picture when it's finished and reassembled.I've never seen another Metcal workstand like this. I'm guessing it's older than the common WS4 workstand like we used at the PCB factory I worked at in the late 1990s:I like it because it's all metal. The WS4 is mostly metal, but the insert that you place the handpiece in is plastic, and those can break (there were a few broken ones at work).

author: GreyWoolfe
author_rank: Unknown
timestamp: December 14, 2016, 12:31:27 pm
content: Good job! Now, what will you do for the crusty, by comparison, power supply?

author: zapta
author_rank: Super Contributor
timestamp: December 14, 2016, 01:22:00 pm
content: Awesome restoration job. Have you considered to add magnets for standby?

author: Monkeh
author_rank: Super Contributor
timestamp: December 14, 2016, 03:50:58 pm
content: Nice work! Mine didn't come out nearly as nice, mostly as I couldn't find an effective way to strip all the old paint.

author: MaximRecoil
author_rank: Regular Contributor
timestamp: December 14, 2016, 07:53:18 pm
content: Quote from: GreyWoolfe on December 14, 2016, 12:31:27 pmThanks. I'm leaving the power supply as-is. I don't mind normal wear and tear, but I hate corrosion. My preference with anything, whether it be cars, arcade machines, or whatever, is to leave an original factory finish alone unless it is severely damaged, such as by corrosion or water damage of the underlying material.Quote from: zapta on December 14, 2016, 01:22:00 pmThanks. I don't really know the specifications to do that (i.e., type of magnets to use and spacing/positioning), but I don't really need it at home anyway. I just turn it off when I'm not using it. It only takes 10 seconds or less to heat up from room temperature, so it isn't a big deal. When I worked at the PCB factory in the late 1990s, something like that (which didn't exist yet as far as I know) would have been good had I been the one buying the tip cartridges, but I wasn't. We used STSS (like the one I have now) and MX-500 stations interchangeably. The MX-500s had a 30-minute timeout feature, though that didn't accomplish much, because the only time we'd go 30 minutes without soldering was during lunch-break, and we just shut them off for that anyway.Quote from: Monkeh on December 14, 2016, 03:50:58 pmThanks. Was it paint on yours or powder coating? Normal paint strippers work fine on most types of paint, but they may or may not work on powder coating. Powder coating is actually just melted-on plastic, so you need something that will "melt" plastic. In my case it was powder coating, and some Goof Off Graffiti Remover that I already had onhand (not the same thing as regular Goof Off) did the trick. I suspected it would work because I've seen it melt at least one type of plastic in the past (polycarbonate, AKA: Lexan).

author: Monkeh
author_rank: Super Contributor
timestamp: December 14, 2016, 08:10:51 pm
content: I'm not sure precisely what it was, only that it was flexible and very, very thick. And gone over more than half the stand thanks to the lovely corrosion. I sanded it as best I could, but it proved near impossible to remove where the corrosion hadn't lifted it. Very durable coating, shame it failed somewhere (bubbles in the sponge tray cracking? Seems to originate from there usually).It's the newer WS4 style, except not the silly plastic holder - chrome plated steel. I believe some of the earlier black ones were painted steel rather than plastic, also.

author: MaximRecoil
author_rank: Regular Contributor
timestamp: December 14, 2016, 09:24:24 pm
content: Quote from: Monkeh on December 14, 2016, 08:10:51 pmWS4, like in the last picture in my original post?That's a WS4, and I've never seen a WS4 that looked any different than that. I've never seen one made out of steel, and definitely not one that was chrome plated. We had a lot of those at work, and they were all die-cast zinc (pot metal), just like the older one that I have is. The ones we used at work were too new (at the time) to be corroded, but I've seen pictures of corroded ones, and it's the same whitish corrosion that afflicted mine:Steel doesn't get whitish corrosion, it rusts (reddish color).I believe that the newest/current MX workstand (WS1) is plastic.You can test whether or not something is steel by seeing if a magnet will stick to it. That works with all types of steel except for certain types of stainless steel, e.g., 300-series, which is austenitic.

author: Monkeh
author_rank: Super Contributor
timestamp: December 14, 2016, 09:30:21 pm
content: Not the base, the iron holder. You know, the bit you were complaining is plastic.I believe those are for the desoldering gun, but you get the idea.I believe it was steel, anyway.. I'll go check. E: No, no it's not steel.. but it is metal. Proof in the pudding:Cast, so it's probably just zinc. The screw holding it is a non-magnetic stainless, though, no expense spared there.. Much better than the plastic rubbish. As I said, pretty sure some of the black examples are metal as well, not plastic.Your photo is a lovely example of how mine looked when I got it.

author: MaximRecoil
author_rank: Regular Contributor
timestamp: December 14, 2016, 10:06:19 pm
content: Quote from: Monkeh on December 14, 2016, 09:30:21 pmAh, that's awesome. I've never seen one with a chromed-metal insert like that. I wouldn't mind having one like that. As I mentioned earlier, the WS4s we had at work had plastic (Bakelite/phenolic) inserts, and some of them were broken.The insert on mine is chromed metal too, as you can see from the pictures. Like yours, it isn't steel; just die-cast zinc, but it has held up very well. The chrome is undamaged on it; no corrosion.QuoteMine doesn't have any screws. The insert is held in place by a Starlock type washer, and then there's a stainless steel spring pressed onto the back of the insert to guard the tip and protect you from getting burned:The design of the WS4 makes that spring unnecessary, but it's good to have on mine.

author: macboy
author_rank: Super Contributor
timestamp: December 20, 2016, 07:38:39 pm
content: Quote from: MaximRecoil on December 14, 2016, 07:53:18 pmI added magnets to mine. I found two strong discs magnets, about .75" by .15" thick, stacked them, and positioned them inside the stand close to the tip. To find the optimal position, I experimented by putting a thermocouple on the tip and just moving the magents around until I got a good reduction. I've measured the temperature reduction to be around 200 F lower which is perfect ... it will definitely extend tip life, but the iron easily recovers in the two seconds it takes to travel from stand to work piece. With that spring you will have a slightly harder time but you could do it.

author: neslekkim
author_rank: Super Contributor
timestamp: December 21, 2016, 12:59:13 pm
content: On the WS1 stand the magnets are not positioned close to the tip, but about 1cm from the handle.The magnets are positioned flat, and looks like halfround magnets, very similar to harddrive magnets.

author: scrofula
author_rank: Contributor
timestamp: January 28, 2020, 06:26:40 pm
content: Good day. can this topic be raised? I got such a stand and I have a question about a steel spring to protect against burns. All metal coasters use non-magnetic metal for its rest. Will the EMF be induced in the spring, which will lead to its heating as well as the sting?

author: scrofula
author_rank: Contributor
timestamp: May 29, 2020, 11:51:08 am
content: I will raise the topic, here are my restored coasters.

author: thm_w
author_rank: Super Contributor
timestamp: May 29, 2020, 08:49:03 pm
content: Quote from: scrofula on January 28, 2020, 06:26:40 pmI haven't seen an issue with that, but I have no way to measure the magnetic field outside of the tip. I would assume they try to keep it concentrated there.The use of non-magnetic metal is probably more to do with casting costs and required detail in the shape of the stand.