MCM Electronics

Vacuum Desoldering Iron By Tenma (21-8240) MCM Part #21-8240

4.5 stars 11 reviews
MSRP: $29.95
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Specifications Top

Vacuum Desoldering Iron
Allows single-handed desoldering of connections, PC boards and components. Spring-loaded plunger and 30W heating element removes most board level components quickly and safely. Easily disassemble for fast cleaning, tip and "O" ring replacement.

Internal plunger pin automatically purges solder from tip with each use. Attached silicon cord is heat and solvent resistant.

Available replacement items:

  • 21-8241 Replacement tip
  • 21-8242 Replacement "O" ring, set of two
    Part Numbers
    MCM Part #:21-8240
    Tenma Part #:21-8240
    Package Specifications & Dimensions
    Weight:0.62 lbs.
    Warranty:365 days
    Need to Return?
    Length:12 in.
    Width:2.54 in.
    Height:1.75 in.
    Shipping Information
    Extra Shipping Charge:No
    Drop Ship:No
    Catalog Pages
    MCM Cat 57, Page 1161
    MCM Cat 56, Page 976
    View in Catalog
  • Product Reviews Top

    • by dragonsbain

      on 6/13/2015

      eater defective or bad

      Overall: 3 out of 5

      good but how much is it supos to smoke

    • by rasterbit02

      on 2/14/2014

      Works Great!

      Overall: 4.5 out of 5

      I agree with all the posted positive reviews. I like that it has a metal tip. Of course it's needed for heating the solder but it has an added advantage over other basic suckers, that the tip doesn't melt and become deformed from the extreme heat. Once I've used a stand alone sucker a few times the tip deforms to where it loses the ability to efficiently aline itself to create the proper vacuum to lift solder from the PCB. I would have liked to see instructions with the unit as other reviews have commented.

    • by jayt

      on 8/15/2013

      Has some linitations, but still great for the price

      Overall: 4.5 out of 5

      In the reviwing instructions they say to avoid references to the price, but then that one field is "Value for the money" so what is one to do? Anyway, the thing is a bit slow to heat up and the tip size is not well suited to very fine work (but for very fine work desoldering braid seems better than any sucking type tool I've used). And the low power is not really well suited to very heavy work. But for work within its ability (which is much of what i do) it works fine, Much easier to use than seperate soldering iron and solder sucker. And the low price makes it a bargin.

    • by nighthawkjw

      on 12/20/2012

      Waste of Money

      Overall: 1 out of 5

      I purchased this item as an alternative to either the dirt-cheap plunger desolder devices (similar to this, with no iron tip) or the MUCH more expensive suction pump (Hakko or Tenma) desoldering stations. You know those red desolder suction bulbs? I get better results with one of those! Maybe the o-ring is bad. I'll look into replacing it and trying again, but I've only had it for two months. I would hope the o-rings last longer!

    • by Snoogins34

      on 10/16/2012

      Great tool for the money!

      Overall: 4.5 out of 5

      I was in the middle of a recapping project, replacing 2 caps on a LCD screen, and was getting frustrated with trying to use solder wick to remove the bad caps. I went looking for a vaccuum-based replacement, and was getting bummed out thinking that my only choices were dedicated plungers (2-handed technique, awkward) or high-end stations. Then I happened upon this desoldering iron, and for the price I bought it sight-unseen based on the other reviews. Honestly, it was worth it just for the time it saved me on this project alone! Heat the gun, cock the plunger, place the hollow tip over your solder joint, and hit the plunger button once the solder is heated. Obviously not as clean as a powered station, but still works very well. The only reason I didn't give it a full 5-star for Quality is because, as others have noted, there are no instructions included. I would've liked to have seen something here, if for no other reason than cleaning & maintenance. Other than that, it's a GREAT value alternative to plungers for simple projects. If you're not ready to spend $$$ on an expensive station, then get this - you won't be disappointed.

    • by garylgaither

      on 10/2/2012

      Desoldering Iron

      Overall: 5 out of 5

      Works great. At last, one handed soldering. Makes work faster.

    • by deniss

      on 9/14/2012

      Excellent cheap desoldering device!

      Overall: 5 out of 5

      I'm a home electronics hobbyist, and I've done a few audio recapping projects where I've had to replace a lot of capacitors. I used to desolder using a copper braid, but that method is not only tiring when you have to remove a lot of components, it's can also damage the delicate vintage circuit boards and overheat components if they need to be reused. So I decided to finally invest in this desoldering device after reading all the good reviews about it here. Let me tell ya -- I am NOT disappointed in the least! The reviewers are spot-on: this device is a great value and works just like it should. I slide the hollow tip onto a component lead that I need to desolder, press the tip against the circuit board, wait a second or two for the solder to flow, and press the button on the desoldering device to vacuum the solder off the board. It's ridiculously convenient after my experience with the copper braid wick. This desoldering device has somewhat of a thick heating rod and a large tip, but I've been able to go into pretty tight places with it where my copper braid would have been useless without first removing a lot of nearby wiring on the underside of the circuit board. So far, I'm very satisfied with this desoldering device. It IS made in China and no instructions are included, but it is still a well-made device in my opinion, NOT a cheap piece of crap, so if you're short on money and need a desoldering tool that will deliver, this is a great buy.

    • by kg4muc

      on 9/14/2012

      Good Tool

      Overall: 4 out of 5

      This is a great all around desoldering tool. I had a premature failure of mine,for unknown reasons it only worked a couple of hours,but MCM graciously replaced the defective tool! Other than that failure ,that I'm sure is rare, it's a great tool for the money! Thanks to MCM for their fast shipping and excellent customer service!

    • by DerekHyps

      on 2/16/2012

      Solder Sucker works

      Overall: 5 out of 5

      I was looking for a solder sucker with a tip with a small hole and bought this one. It wasn't small and just as big as the other five solder suckers I have that aren't worth using except for large components. To my surprise this solder sucker worked great. I dismantled 50 components off a stereo in less then 30 minutes. The key to this unit is the fact that it is a solder gun and sucker in one. Anything else is a waste of time. You know how fast solder cools. If you have to heat a component up with a solder gun and then use a separate tool (solder sucker) to suck up the solder, it's already to late. The fact that the tip on this unit has a large hole is actually a plus. You can unsolder small components who's leads are bent over and the fact that the vacuum is attached to the solder gun makes instantanous extraction without overheating the component. It made a believer out of me.

    • by eskoog

      on 7/9/2008

      No Instructions, Included tip too big for most use

      Overall: 4.5 out of 5

      To remove the barrel assembly, lift/pry up the push rod as close to the barrel as possible. Be aware that the internal spring will pop out! IMHO, the 21-8241 tip is the most useful. Grease the barrel and plunger with vaseline to keep the solder from sticking & park in the UPRIGHT POSITION [tip up] to keep the solder from falling back into the heating element. Get some 1/16" music wire at a hobby shop to make a tip cleaner. This desoldering tool is great for home users or one off repair jobs. I plugged mine into a light dimmer to regulate the temperature and idle. Geek1945

    • by jrgiza

      on 2/14/2008

      Fantastic timesaver!

      Overall: 4.5 out of 5

      OK - any of us who do any amount of desoldering would rather have the Hakko station. For the money though, this cannot be beat. Desoldering with one hand! I've had mine at least 6 months now nad have used it a lot. One tip lasted me quite a while, and new ones were cheap. Great all the way around.

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