In my attempt to grow my repair gear arsenal, I recently picked up an inexpensive hot air station which gets pretty decent reviews around the web, a WEP 858D. This is the same as the Atten 858D, only it’s 110V (for us Americans) vs the Atten being 220-240V. Tenma also rebrands this unit as the 21-11425. I purchased mine though a company called Sain Smart for $52 with free shipping. Only down side, it’s from China, so it took about a week to arrive (which stuff from the US can take that long as well).
Early in the production of these units by Atten and WEP, there were some serious production issues that were highlighted on eevblog. At least one person’s was wired with the hot leg to the chassis (serious shock hazard), where a few others were just grounding issues (mainly that the unit was fully painted, so the ground connection to the chassis wasn’t making good contact), and a couple also were fused on the neutral leg. The main issue, which I also had, was the power switch was switching neutral, rather than hot. While this isn’t a MAJOR issue, it’s still not considered to be up to code, and is probably done to save a couple wire cuts, and a bit of time.
Anyway, I got my unit, checked all the grounded surfaces, opened it up and checked for stray solder, fused hot, etc. All looked pretty good, except the power switch was switching neutral. Worse, when I fully opened the unit, the power switch fell apart (see picture). Awesome. Figuring I’d give it a shot, I emailed Sain Smart and told them about the switch. Within 24 hours, I heard back that they didn’t stock the switch, but they’d be willing to pay for a replacement switch, including shipping from eBay. Knowing the eBay ones would be similarly sketchy, I asked about purchasing one from Digi-key, and they agreed. So, after some searching and measuring with my crappy calipers, I found the equivalent made by Cherry, the CH755-ND. I ordered 2 (never hurts to have a spare), and waited for them to arrive. And, I few days later, they did!
The new switch fit perfectly, and the same day I got the switch, I got the $4 credit via Paypal from Sain Smart. Awesome! Soldering in the replacement was cake. My only tip is, be quick. Switches are plastic, so if you apply heat for too long, you’ll melt things.
So, how does the unit work? Well, I haven’t done any reflow work with it yet, but I will say it kicks the pants off my hot air gun for doing simple shrink wrap work (certainly don’t have to worry about it melting the wire, or plastic around it). The unit is very quiet (relatively speaking), small, and really, just does the job. I’d highly recommend it for the $50 or so they go for if you plan to do anything with hot air. I’d enjoy being able to switch it to Fahrenheit instead of Celsius, but it really doesn’t matter that much. And I love to sleep function. I can use it at 300C, put it in the cradle, and 15 seconds later, it’s off (the system cools down to 100C before going to sleep). Pick it back up, and it’s back to 300C in no time. Better still, it remembers previous settings on power on. =)
Highly recommended if you are comfortable fixing the wiring.
Gustavo Contreras says
Thanks for your review, a couple of questions,
Did you already use your WEP858D for a real work? In general, how it worked?
I assume that you fix the neutral switching issue, I mean, do you reinstall it to interrupt the live? O just are you using it just like it arrived (in the neutral)?
I’m asking it because I just did buy one , and want to know if I have to do any modification.
Thanks and best regards.
Yes, I’ve used it on some SMD work, and use it all the time for things like heat shrink. The unit works great, I actually really like it. I did rewrite the switch to switch on live, and in the process the switch actually broke, which the seller was nice enough to refund enough money for me to buy a good (not crap) switch off Digikey. So the unit currently works as it should. I haven’t purchased any replacement heater elements, but they seem to be pretty easy to find off eBay, so I’m not too worried. I would say you could leave the unit switching neutral (if yours comes that way) without too much risk. Hell, some countries electrical codes allow for this, so it can’t be THAT dangerous. =P
Only thing I don’t like about the unit is the intake for the blower on the handle is easy to cover with your hand, so just take note of which side you have your hand against. =)
Thanks, and good luck! Hopefully you enjoy the unit! Oh, and do check continuity between the tip and the ground pin.
Blair Groves says
I just purchased the same unit, and also found the neutral was both fused and switched. Further to that, I had the fuse holder disintegrate when I simply checked the fuse rating and screwed the cover back on. I also found the heater tip was not grounded, despite the green wire from the heater assembly being grounded to the circuit board. I rewired it to fuse and switch the hot conductor, replaced the crappy power switch with a nice illuminated switch , replaced the crappy fuse holder, and ran a ground wire from the place on the circuit board where the heater ground wire is tagged to, to the mains ground terminal where it attaches to the transformer mounting screw. Apart from these issues (which really have to do with the electrical “regionalization”) which were easily fixed.
Wow, that’s a lot wrong with that unit. I would totally contact the seller and tell them everything you had to do… see if they’ll chip you a refund.
But, I guess you could look at is as sort of a kit build. =)