Tip Grinding (again)

[Jidis]

Hey,

I was told in a thread a little while back that the copper tips were the grindable ones. I've been doing that a while, and have been spinning them in a drill press to shine them back up with xfine sandpaper. I still get that charcoal gray look after they're heated up and haven't seen one get to where I can "flood" the tip with hot solder and spread it around the tip. It usually beads off. They're not the worst, but they're not like the shiny, evenly solder coated tip, where everything always flows exactly where it's supposed to. Solder rolls around on the ends sometimes too (instead of jumping to the target joint).

Is that not good enough, and is there a step I'm missing or something? I usually get them as smooth and shiny gold as I can and then attach them, flux them and let them heat, at which point, I'll try to apply some solder to them. They're usually a dull black a couple minutes after they heat up.

                                                            -George ??? 

[Fx3_hdrive]

i have a partially same problem, i had a new tip, i'm not entierly sure if it was copper, but after couple of weeks of intense soldering it started "eroding" away, now instead of a fine point, its about 4mm dia blunt, like it has been broken  ???

i'm afraid to grind it because its my last tip

[Jidis]

I'm lucky my general purpose iron (Ungar) can take some easy to get copper tip from RadioShack. It comes in a three pack of some crappy dimensions, but they can be easily ground.

If you didn't catch the old thread, I *think* it's this-

http://www.midibox.org/forum/index.php?topic=5093.msg31608#msg31608

A search turned up some weird variant with missing posts, but that should be the tip grinding part.

I still think there's a trick to retaining the quality. I think I'm getting it smooth enough. If people are grinding with files, this has to be at least that smooth. I do remember a usenet post involving the heating/coating of a plumber's flux and solder with a propane torch or something (higher melting point). I can't remember if it was agreed upon as a good idea though. I may check the Yahoo PCB group, if it's not too off-topic. That place has been like grand central station lately, with many well informed responses. If I can find any good info, I'll return it here.

I get the "blunted" tips too. That's when I usually re-grind.

Any additional tips here would be welcomed. (no pun intended ;))

-George

[Wisefire]

i dont know what the fuss is all about.. im grinding mine with an stationairy stone grinding thingy. its a small powertool of some sort.. i dont know the exact name.. i grind it to a sharp point, put some solder on it.. and start soldering.. it'll erode again.. and i sharpen it again.. it works great.. and i can solder very precise with this method..

[Jidis]

Wisefire,

My points are fine. I can get them as sharp and shiny as I want, but they just get dull and brown/black right after they heat up the first time, and they don't keep that clean solder coated surface, where I can wipe it across the tip while soldering, or before turning it off to protect it. :'(

-George

[el-bee]

Are you using purified water in the tip cleaning sponge? Tap water has impurities that will burn to the tip and make it dark.. To me, grinding a tip sounds a bit too hard a treatment (damaging the tip surface). A light brushing with steel wool or a fine steel brush followed by some flux and tin has worked for me.

[Jidis]

I think I made some headway with this last night. I may have been waiting too long between the grinding and soldering stages, and allowing something to happen to the tip. Someone in the PCB group grinds his while it's hot.

:o

Last night I ground the tips in the press and smoothed them back up afterward. I then screwed one onto the iron and carefully wiped the tip with a paper towel wet with ferric chloride to eat whatever might be on the surface layer (not sure that's a good idea). I waited a minute, and twisted some steel wool around it to clean it off. I immediately smeared flux over it and began heating it up. I started touching the solder to it before it was hot enough to melt, and as soon as it would melt, I was able to "paint" the whole tip with solder. Two of them were cooled down and put away with the solder on them, and the third, I was able to use the rest of the night, being careful to keep it clean and coated.

:)

PS (el-bee)- The pure water sounds good. I'll switch to that. From the recommendations I've gotten, it sounds like the copper tips are solid all the way through, so you're just ending up with the same surface, as long as it's smoothed out well. I've got good plated tips here too, and I'm careful not to grind them or anything.

                                                            -Take Care

George

[Fx3_hdrive]

hmm, are plated tips better? or do they errode as fast as normal copper ones?

home electroplating, thats an idea  ;D

(are they nickel plated?)

[moebius]

I'd say plated are better.

Anyway, I'm using an Antex iron, which has a different way to attach the tip. In the years of use it has turned dull gray, but tip is still nicely tinned. (But I usually tin it, when I'm turn it off and wipe the excess solder off while it cools off.)

Moebius

[Jidis]

hmm, are plated tips better? or do they errode as fast as normal copper ones?

I thought some were iron, but I'm not sure. I've got some really nice Wellers here, but the package doesn't say. It looks as if the "immediately coat after grinding/cleaning" thing is going to make them about equal. Plus, you can get weird shapes and re-sharpen. I'm thinking of doing a wide flat one for board tinning out of these worthless fat pyramid tips I've got. I did use one of the plated tips, plus both my rework station's tips are plated, and everything I've used looked equally dirty. I usually clean during soldering with a sponge and flood the tip before turning it off. The plated stuff may just look dirty (not sure), but the coppers were unusable. The newly coated coppers seem just as good as anything I've had and the coating seems to stay on them even with a good wiping.

                                                               Good Luck

-George

[Fx3_hdrive]

i ask because at our collage we have a dosen soldering stations and they get constant punishment from the students (us  :P) but they look so good, their completly covered in a coat of solder, and the tips shape looks like new. could they be plated??

i just want a tip i can rely on, knowing that it wont fk up in a weeks soldering like mine did

[Jidis]

Fx3_hdrive-

I've been meaning to reply. I have noticed now that they do NOT appear to hold up as well "shape-wise" as the good coated tips I have, but they are cheaper and easier to get, plus you can make weird shapes.

I wasn't taking as good care of the nice ones, so they are a bit crusty now, but they're still sharp. I've got a couple I haven't opened yet. The copper solder coats are holding up just fine, now that I know the procedure, and they're not hard to regrind.

-George

PS- I may be grinding them a bit too sharp. I've never bought a copper tip as sharp as what I'm making, so maybe that metal is better suited to chisel points,etc.  I wish I could make something shaped like a hammerhead shark for heating a row of IC pins at the same time.

                                                                                                                                                                         ;D