Hot Air Rework for through hole "wave soldering"?

[pappasmurfsharem]

I have a "fancy" chinese solder/rework station.
http://www.ebay.com/itm/3-in-1-853D-SMD-DC-Power-Supply-Hot-Air-Iron-Gun-Rework-Soldering-Station-Welder-/381253195679?hash=item58c476179f:g:jVkAAOSwbsBXn~HE


So say for PCBs where the pads for a grouping of components are all in the same column/row. Has anyone tried cutting solder wire to roughly the length of the lined up pads and used the hot air to wave solder?

I'd like to think the surface tension might help keep solder bridges at bay, but then there is also the possibility of not getting a clean joint from not enough direct heat.

[R.G.]

Why not just buy yourself a syringe of solder paste?

[pappasmurfsharem]

Why not just buy yourself a syringe of solder paste?

STOP MAKING SENSE RG!

I've never used the stuff, I know its common for SMD work, but is there enough material suspended in the paste to get solid connections for throughhole pads? (obviously you could compensate with more paste)

I'd assume so since you recommended it in the first place. 


$6.47 for 4oz, might be worth trying.
https://www.amazon.com/Oatey-30013-No-Flux-4-Ounce/dp/B000BQO4AK/ref=sr_1_3?ie=UTF8&qid=1472313853&sr=8-3&keywords=solder+paste Not for electronics.

I have plent of syringes from my other hobby (making E-Cig Juice)

[R.G.]

It's the stuff they use for all SMD work. It's a (very) thick paste of solder dust in a sticky suspension of flux. Yes, it is suitable for making electronic joints. I have used it for getting a perfect solder joint between a copper board and a brass washer by spreading just the bottom of the washer with paste, placing it, then heating the washer.

And yes, you're right, be sure you get stuff rated for electronics. The other stuff is for sweat-soldering pipes and such where you can elaborately clean the corrosive flux off. Bad juju indeed for electronics.

Like heatsink goo, it's messy and somewhat expensive, but very good for what it does. I don't know where you are, but here most mailorder places have syringes of the stuff available. It's thick enough that you probably won't be able to force it through medical needles, but the syringe without the needle will work OK, I think. I just dabbed mine with a wooden toothpick to get an appropriate sized blob. The blob shrinks a little when reflowed, as the flux liquifies and/or evaporates, and molten solder sinks into the joint being made.

Just speculating, you might be able to put a nozzle on a paint-scraper style heat gun and make a wide line of hot air to reflow a certain width as you pass it along a PCB, or better yet, have the line of heat pointed up and pass the PCB over it. But be aware that you will need several trials (read that as "throw away the first several trials") till you get your process right.

[pappasmurfsharem]

They are 20, 18, 16 awg syringes. So they will probably work fine.

I know of the stuff, I just assumed it was minmal ammounts of solder dust since it seems to be primarily for SMD work (aka mostly flux-little solder, since SMDs don't require a whole lot).

[R.G.]

I know of the stuff, I just assumed it was minmal ammounts of solder dust since it seems to be primarily for SMD work (aka mostly flux-little solder, since SMDs don't require a whole lot).

I'm sure there are variations. The tech lit on the stuff ought to tell you the percentages.

[PRR]

> pipes and such where you can elaborately clean the corrosive flux off.

I don't think plumbers post-clean their joints.

I have assumed the difference is that pipe/tube is thicker wall, and the acid is only on one side. The acid-to-copper ratio is lower. The acid will be used-up before the pipe is eaten-through.

There is also some limit how much flux you can get in a pipe joint. The pipe-fitting clearance is small and well controlled.

Also pipe may be stored outdoors, or hung in a dank cellar, so oxidation can grow very ripe by the time installation or repair is attempted. Pipe can need strong flux. (I have used rosin flux-core on very fresh new pipe and fittings with lasting success, but I would not try that on the aged pipes I found in this house)

Wires are some smaller than pipe walls, the flux is all-around, and we sometimes find flux-blobs bigger than the wire. High flux/copper ratio, more eating-away before the acid gives up, rotten connection.

I actually have not seen a acid-flux problem in some decades. However the NO Acid Flux!! rule IS well-enforced in most workplaces. In computers, possession of acid flux was grounds for instant firing. As this was days when most technicians were general enough to do plumbing on the side or at home, it was enforced.

Another place I knew hired only women. Unlikely to possess acid solder. And pay was so low, they were very unlikely to bring in their own solder (more supplies walked out than in).

[R.G.]

I don't think plumbers post-clean their joints.

I have assumed the difference is that pipe/tube is thicker wall, and the acid is only on one side. The acid-to-copper ratio is lower. The acid will be used-up before the pipe is eaten-through.

I had in mind other piping, not plumbing, but yeah, most plumbers now have a fairly specialized routine for copper pipes - which are going out of vogue. And plumbing flux is only applied to the outside, but internal contamination is impossible to prevent. I think the *water* cleans it pretty quickly inside. Not a nice thought, but probably not a disaster either, since the old standard flux was mostly a zinc-chloride gook that dissociated into zinc salts and HCL to do the actual fluxing. HCl is no picnic, but it's not out-and-out poisonous either. We make the stuff in our stomachs as a digestive fluid.

Pipe can need strong flux. (I have used rosin flux-core on very fresh new pipe and fittings with lasting success, but I would not try that on the aged pipes I found in this house)

Sandpaper. They sell rolls in the plumbing section of Home Despot.

I have an entirely different problem. I collect and use rainwater for all my potable water. Recently had it tested, and it's ph 4.35 - well into tomato-juice territory, although not into lemon-juice range. Good thing my plumbing is PEX. Things that will dissolve crosslinked polyethylene (other than heat) are deadly beasts indeed. I'm working on the dosing regimen to get it back up to neutral.

[pappasmurfsharem]

Looks like another user did a video in january actually.


http://www.diystompboxes.com/smfforum/index.php?topic=113079.msg1045654#msg1045654

[PRR]

Reported.

[pappasmurfsharem]

Reported.

Huh?

[PRR]

> Huh?

Not for you. There was a Russian Spam. I clicked "Report to moderator", and also noted that act so others would know it would be dealt-with. Now the spam is gone (thanks!). My "Reported" post could have been removed also, but I guess Aron(?) missed it. And I guess you saw my post without the spam, which must be confusing.

[pappasmurfsharem]

> Huh?

Not for you. There was a Russian Spam. I clicked "Report to moderator", and also noted that act so others would know it would be dealt-with. Now the spam is gone (thanks!). My "Reported" post could have been removed also, but I guess Aron(?) missed it. And I guess you saw my post without the spam, which must be confusing.

It was lol... I thought that might have been the case but I thought I had just viewed the topic not long before and I didn't see anything at first. lol