Harmonica Lewinskey
72 posts
Aug 06, 2015
10:18 PM
|
So as I eagerly (and fearfully) await the arrival of this NOS Shure element so that I can solder it into this shell for the first time ever, I was doing some research on techniques for soldering heat sensitive materials (such as mic elements) and I came across this nickel filled electrically conductive epoxy stuff. Its basically soldering but with absolutely no heat. Seems like a good option for working on microphone elements, right?
https://www.atomadhesives.com/AA-DUCT-903-Nickel-Filled-Electrically-Conductive-Epoxy-Adhesive?search=905
Maybe i'm missing something here, but I think I'm gonna order this stuff..
----------
-LeWin$key
|
STME58
1420 posts
Aug 06, 2015
10:58 PM
|
The fact they gave you a comprehensive data sheet on the product is a good sign. The data sheet shows the tensile strength at 9500 PSI which is on the high side of solders as you can see here on page 327 If you are going to have a problem I expect it would be with the resistivity. Antimony solder has a resistivity of 1.449E-7 ohms per meter where this materal says it is less than .038 ohms per centimeter. That is several orders of magnitude difference. Someone with more experience in electronics than I could tell you what the implications of this are. If you get a good electrical and mechanical bond on the wires by twisting them tightly together and use the epoxy to hold them and prevent corrosion, it might work fine. It may also be that there would be so little of the material separating the wires that the huge difference in resistivity may not matter.
Last Edited by STME58 on Aug 06, 2015 11:02 PM
|
STME58
1421 posts
Aug 06, 2015
11:07 PM
|
The silver version is weaker mechanically and has about half the resitivity of the nickel, but nowhere near the resistivity of antimony solder. Unless you have a solid electrical connection before you apply the epoxy, these joints will have higher resistance than a soldered joint. Whether the difference is significant to the circuit I will leave to a more qualified person.
|
Pistolcat
826 posts
Aug 07, 2015
12:49 AM
|
There's usually enough wire to the elements so you can use regular soldering. I would wait until I got the element if it was me. That said: I know next to nothing about electronics... Good luck
----------
Pistolkatt - Pistolkatts youtube
|
didjcripey
948 posts
Aug 07, 2015
1:04 AM
|
Don't bother. Learn to solder if you don't already know how. Make sure that if you have to solder close to or on the element that your iron is plenty hot enough and work quickly. You can use something like an alligator clip for a heat sink, but it shouldn't be necessary.
----------
Lucky Lester
|
arnenym
357 posts
Aug 07, 2015
2:13 AM
|
Listen to didjcripey advice and practice on som wires before you solder the element.
There is a lot of clips on Youtube on how to solder.
|
chromaticblues
1687 posts
Aug 07, 2015
4:05 AM
|
Any good electrical solder will do. The trick is to use a low wattage soldering iron. I think mine 15 watts.
Twi things you should look up on you tube. 1 how to tin the soldering iron tip. and 2 how to solder thin wire. Basically you just have to do it fast.
|
Harmonica Lewinskey
76 posts
Aug 07, 2015
6:48 AM
|
Thanks guys, looks like I will be soldering the old fashioned way. I'm not too worried, since it is a NOS element it looks like the leads are a couple inches long, and all of the soldering I have done before has been to build tiny scale furniture and other scenery in 1/4" scale so I am pretty good at making tiny precise solders. I just saw that stuff and thought it looked like a good option to be extra safe.
Cheers!
----------
-LeWin$key
|
STME58
1423 posts
Aug 07, 2015
8:33 AM
|
The experiences Rotana describes are not surprising based on the data sheet for the product.To put the resistivity numbers in perspective, if a 28 gauge wire was made out of the epoxy and out of solder and a length cut of each that had a 1 ohm resistance, the epoxy wire would be 0.2mm long and the solder wire would be 537mm long.
|
isaacullah
3042 posts
Aug 07, 2015
9:04 AM
|
@chromaticblues " The trick is to use a low wattage soldering iron. I think mine 15 watts."
Actually, this is, unfortunately, a bit of myth, which has been widely propagated in the internet age. All soldering irons have to achieve a minimally-hot temperature, or they wouldn't melt the solder. The wattage of the soldering iron has less to do with the absolute temperature that it can reach than it does with the speed at which it regains that temperature between uses. What this means is that lower-wattage irons, which are cheaper and more widely available, take longer to get back to "solder-melting temperature" between uses than do higher-wattage irons. This is a disadvantage when you have many solder connections to make, and means that many less-experienced electronics hobbyists (using low-wattage irons) try to move on to their next solder joint before the iron is hot enough. This leads to them making a lot of "cold-solder" joints that are brittle and which won't last.
I currently use an adjustable-temperature 50-watt soldering station that I got at Fry's electronics for around $30, made by Velleman. It works really well, and lets me easily make good, solid solder joints in a variety of situations. For electronics, the main thing to look out for is that the soldering tip is the right size and shape. This is even more important than absolute wattage in terms of thermal transfer. The tip should be quite slender, and pointed, not thick and wedge-shaped. You should also keep clean at all times by wiping it (while hot!) on a sopping wet cellulose sponge after each solder joint. Periodically, you also need to "tin" the tip, by applying solder directly to it, while it is hot. The tip should stay "shiny" with a thin coat of solder over it at all times. Otherwise, it will start to erode.
Finally, and something that most amateurs don't know to do at first, you NEED to buy a separate container of flux (either liquid or paste flux), and you NEED to apply that to your jointing surfaces before you make the solder connection. This is regardless of whether you are using "rosin core" solder, which has some flux built into it. Applying flux first will make the joint happen much more quickly, smoothly, and cleanly. This is a must-do because it means your hot soldering iron needs to spend less time on the metal, which means it's less likely to heat up any heat-sensitive components. It also means that you will be much more likely to make a solid solder connection between the jointed components, and less likely to make a brittle "cold-solder" joint.
Oh, and if you are soldering two wires together, be sure to twist them together end-to-end this way first: https://www.youtube.com/watch?v=Q9G9gaokqvM
Good luck!
EDIT: Here's a good article with some soldering facts you may want to know: http://www.circuitrework.com/guides/7-1-1.shtml
Added links, and fixed typos, grammar.
----------
YouTube! Soundcloud!
Last Edited by isaacullah on Aug 07, 2015 10:00 AM
|
STME58
1424 posts
Aug 07, 2015
9:15 AM
|
isaacullah, thanks for posting that. I was thinking along those lines when I saw the post about low wattage, but from a thermodynamic perspective, not from experience. I have very little experience soldering but I have done it with a 10w uncontrolled iron from radio shack and with the high wattage closed loop temperature controlled units where I work (which have a wide selection of tips so you can get one just right for the job) and there is a huge difference in the quality of joints created and the time and ease with which it is done.
|
Greg Heumann
3072 posts
Aug 07, 2015
9:49 AM
|
I agree that:
a) DON'T use the epoxy. What if you have to or merely want to UNsolder it?
b) What's said above about low wattage soldering irons is correct. Just about how long they take to get to temperature. The MASS of the tip and the surface area of contact controls how much heat is transferred to the work.
c) If you always pre-tin both parts to be soldered, then you only need to apply the iron until the solder flows when joining the two parts - and that should be a couple seconds or less. As long as the iron is at a reasonable temperature (mid-600's) you won't damage an element this way. No flux required. (I do use flux for tougher jobs sometimes but not when soldering wires to elements.)
I use a Weller WESD-51 soldering station. I LOVE it. Ready to solder in about 30 seconds after you turn it on - great temperature control. If you solder much, make the investment.
P.S. A single low impedance XLR volume control I make has 5 wires (thats 10 stripping and tinning operations) and 11 soldered connections. Other products are similar. And I have made THOUSANDS. So.... you can trust me!
----------
***************************************************
/Greg
BlowsMeAway Productions
See my Customer Mics album on Facebook
Bluestate on iTunes
Last Edited by Greg Heumann on Aug 07, 2015 9:57 AM
|
didjcripey
949 posts
Aug 07, 2015
2:19 PM
|
Why do americans say 'Sodder' when the word clearly has an 'L' in it?
----------
Lucky Lester
|
SuperBee
2759 posts
Aug 07, 2015
3:24 PM
|
Same reason for drinking erbal tea, ucky Esther. You say potarto...fair dinkum.
|
SuperBee
2760 posts
Aug 07, 2015
4:01 PM
|
But seriously...it seems possible that, as with herbs, the North American pronunciation is an older form, and that the British form has changed. There are a few hypotheses to explain the difference. One thought I found quite interesting surrounded pronunciations of the word 'falcon' and how the 'l' can easily disappear if you pronounce the A as OR as in hawk. You can put it in too, but it's easy to let it be silent, as indeed is the L in walk, talk, half...although in half you can pronounce the L, as the Scots do.. How this relates to Solder...if you modify the vowel, like Sorlder...it's then easy to leave the L relatively silent. Just as you could pronounce half as hulf or huff...it's easy to change the pronunciation . A bunch of the time with letter L it's a modifier that indicates a subtlety in the vowel sound. Letters L and H are quite interesting.
|
STME58
1425 posts
Aug 07, 2015
4:54 PM
|
There can be some problems with L and R on the other side of the world also. 
My sons are currently at the World Scout Jamboree in Japan (which is part of the reason I can't afford to attend SPAH this year) and on the way one of the Scouts snapped this picture.
I have always wondered about the word colonel pronounced kernel.
Last Edited by STME58 on Aug 07, 2015 5:10 PM
|
didjcripey
951 posts
Aug 07, 2015
8:18 PM
|
So much to learn Bee, thanks. But potarto? Its a petaytah to me ;)
----------
Lucky Lester
Last Edited by didjcripey on Aug 08, 2015 12:15 AM
|
