DSi Fuse Replacement Problem - Help Wanted

[actualkoifish]

I am trying to replace the fuse on a DSi power board. I have the fuse and I have a couple different tools:

-soldering iron
-hot air station

and different solders:
-unleaded solder
-leaded 60/40 solder
-solder paste
-plenty of flux
-solder wick
-solder sucker (cheapo one, nothing fancy)

along with various other tools (tweezers, spudgers, helping hands, etc.)

note: I have never used the 60/40 or the solder paste; both were bought on suggestion as "good to have when you need it"

I have a huge amount of trouble when it comes to getting the fuse to stay in the right position. When I first tried soldering it on, it ended up being wildly placed; The fuse was sitting up on top of two big blobs of solder.

I desoldered it and am trying again. I have seen videos where someone leads the two pads, places the fuse on top, and then heats the pads with hot air until the solder liquifies, and the fuse jumps into place (with a little prodding from tweezers). As hard as I try, I cannot replicate this. Even on 1% air force, the hot air station blows the fuse away, and I am not dextrous enough to keep the fuse in place with tweezers. I keep trying, but it goes off center or something else happens to screw my work up.

Is there a good option that I should try, given the hardships that I am having? Should I just try using solder paste, getting the fuse in, and hoping it will heat without being blown away if I do "something differently" with the hot air station? The video I have seen shows the user blowing from the side; I cannot hope to do the same, it seems, because it blows the fuse away. Please help, I am frustrated and unsure of what to do.

 

[JuanMena]

I have a huge amount of trouble when it comes to getting the fuse to stay in the right position. When I first tried soldering it on, it ended up being wildly placed; The fuse was sitting up on top of two big blobs of solder.

The way to solder small things is to let superficial tension do it's work. For that you must clean off solder your solder points, leave the copper only, add paste or flux, them position your small fuse and heat with solder. Superficial tension (as flux becomes liquid) will be held by the copper and you won't have to struggle holding small components.
But it requires skill, and your hot air gun is the best to do this job.

I desoldered it and am trying again. I have seen videos where someone leads the two pads, places the fuse on top, and then heats the pads with hot air until the solder liquifies, and the fuse jumps into place (with a little prodding from tweezers).

Superficial tension at work

As hard as I try, I cannot replicate this. Even on 1% air force, the hot air station blows the fuse away, and I am not dextrous enough to keep the fuse in place with tweezers. I keep trying, but it goes off center or something else happens to screw my work up.

Try paste with low heat resistance solder. Or you can buy flux with little tiny bits of solder included.

Is there a good option that I should try, given the hardships that I am having?

A bit more of work but I think you should try the old school method, solder one side to hold it in place and then complete the job by soldering the other end.

I really can't say what else to do, since I'm a draftsman so my pulse is very good and steady. Alternatively, use a microscope.

I've been using a 5X magnifying glass with leds on it. Not the best, but certainly helps.

Post automatically merged: Sep 26, 2023

The video I have seen shows the user blowing from the side; I cannot hope to do the same, it seems, because it blows the fuse away. Please help, I am frustrated and unsure of what to do.

Try blowing hot air from below your board and placing the fuse eith tweezers. But remember to isolate with aluminum tape the side you'll be heating!