exxos's Atari, Amiga & retro forum

DoG wrote: 15 Feb 2021 19:37 Maybe needs more liquid flux?

IPA can't get through it nevermind anything else ..

In a galaxy far far away....

I've been looking for better paste. The one I think I am using is T3 paste, and yet this isn't recommended for anything below 0.4mm! Considering its shipped with the printer to use 0.25mm nozzles ! and I am trying to use 0.15mm ! :roll:

So T5 paste seems to be as good as it can get. Iv'e just ordered the same type of paste as I am using now (but T5 version) and some other alloy combo (also T5) to compare those...

I've also ordered a cheapo box of nozzles as cleaning them seems near-on impossible.. While they are not "designed" for my use, I can't really see them being any different.. Then at least, if they get blocked, ill juck chunk them. The current nozzles are like £20 a pop and i've killed several of these already :cry:

Farnell messed up my order AGAIN and sent wrong tips :cussing: Paste I could only find in stock at CPC.. only order is on hold as its .. out of stock :cussing: New tips turned up which I ordered last year from another UK company, so I guess thats a win.. If only they had labeled the things up with the right part numbers :cussing:

So the paste is Sn42Bi57Ag1 88.5% 25-45 T3 (which is what I have been using for ages and came with the printer) . According to other datasheets, T3 shouldn't be used less than 0.4mm dia.

INITIAL TEST (NOT PRINTING)

34G nozzle(green) - 0.1mm - couldn't get paste though it at all.
25G nozzle (red) - 0.25mm - paste comes out
21G nozzle (purple) - 0.5mm - paste comes out

EDIT:

25G nozzle blocked after a short while printing..
21G nozzle I was unable to get any sort of consistent results.. seems very "globby". Some pads had more paste than others.

ARRGGHH FFS! :pullhair: :cussing: :cussing: :cussing:


I guess it can't cope with the slightly longer nozzles :cry: :cry: Will have to see if I can cut them down :(

I removed one of the washers which I was using to lift the PCB up with (it has parts on the bottom so has to be lifted up to clamp it level) and I got it printing!

Though using the 25G nozzle, it started fine(ish) but struggled on a larger 0805 pad. So a hour of faffing about, I got it to the point where the paste was coming out way too fast. This happened when I lifted the print height 0.2mm more.. So I lowered the settings to decrease the paste flow, and it stopped totally :roll: I put them back to what they was previously and it still is not flowing. So the same thing happened as normally does, that the paste has clogged the nozzle again :roll:

I'm trying to get a hold of some T5 paste to re-try the same size nozzle but with the finer paste.. wish me luck!

Finally got my T5 paste.. just doing "the purge" then will try it on some TOS206 decoder PCBs as they are out of stock again...


EDIT:

So this is blocking up just as bad as before :pullhair:

The T5 paste looks "wetter" and harder to see the solder balls, so the paste is "finer" and yet its still getting stuck in the nozzle :roll: If I go back to these "brute force" settings I can print kinda as before...

I am using the RED nozzle (0.25mm) but it should get through a lot finer that that anyway. This nozzle is just taking considerable force to get the paste to come out. Much more "kick" and cogs start to slip kinda force! All these tests are costing me a fortune in solder paste tubes :(

I will see if I can cut down the length of these tips.. (I couldn't get it any better with a original nozzle either)

This all sounds a right pain.

I seem to remember you saying that the manufacturer does sell their own solder at an exorbitant price. This is probably why they get away with it.

stephen_usher wrote: 12 Mar 2021 15:18 This all sounds a right pain.

I seem to remember you saying that the manufacturer does sell their own solder at an exorbitant price. This is probably why they get away with it.

Yeah, thing is , I use the same alloy as is quoted on their label. But I really starting to wonder if that's a load of BS and there is something different in it. I am thinking to just buy their own brand stuff to try that again.