Go Down

Topic: Soldering iron (Read 8105 times) previous topic - next topic

jboyton

#15
Mar 19, 2015, 09:36 pm Last Edit: Mar 19, 2015, 09:38 pm by jboyton
I'm new to Arduino and at this point don't plan to do all that much soldering. While a $200 Weller would be really nice I couldn't justify that, at least not at this point. That would be more than I've spent on everything else combined. So I bought an inexpensive adjustable iron ($20) and a simple stand ($6). When I'm soldering and producing what are clearly less than perfect results I wonder how much of that is due to my iron versus my lack of experience.

Shpaget

Are you using flux?

DrAzzy

#17
Mar 19, 2015, 09:51 pm Last Edit: Mar 19, 2015, 09:52 pm by DrAzzy
I'm new to Arduino and at this point don't plan to do all that much soldering. While a $200 Weller would be really nice I couldn't justify that, at least not at this point. That would be more than I've spent on everything else combined. So I bought an inexpensive adjustable iron ($20) and a simple stand ($6). When I'm soldering and producing what are clearly less than perfect results I wonder how much of that is due to my iron versus my lack of experience.
We could tell (well, give some level of assessment) you if you posted a nice closeup of some soldering you did on a PCB. Bad soldering irons and poor technique usually look different.
ATTinyCore and megaTinyCore for all ATtiny, DxCore for DA/DB-series! github.com/SpenceKonde
http://drazzy.com/package_drazzy.com_index.json
ATtiny breakouts, mosfets, awesome prototyping board in my store http://tindie.com/stores/DrAzzy

jboyton

#18
Mar 19, 2015, 10:19 pm Last Edit: Mar 19, 2015, 10:21 pm by jboyton
We could tell (well, give some level of assessment) you if you posted a nice closeup of some soldering you did on a PCB. Bad soldering irons and poor technique usually look different.
Okay. For your amusement:






The soldering iron:
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&productId=116572

CrossRoads

Get some high percentage isopropyl alchohol and clean that flux up. I use 99.9%, but I get it an electronics supply place. You can get perhaps 95% at the drug store.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

DrAzzy

Eh, that doesn't look too bad. It looks like in the bottom picture, you soldered the wires from the side of the board that the wire is on, resulting in the insulation getting singed. Where possible, you want to solder from the other side from the thing you're attaching - that way, you've got better access to the end of the wire/pin, and you don't have the soldering iron poking so close to the insulation.

Cleaning the flux off makes it look prettier, but that looks like normal rosin core solder - you can leave that on, it just looks ugly. Some cleaning with IPA helps, but IME it doesn't get it all off

(Trivia: drug-store IPA caps at 91%, since going higher is hard. To get 91% they just distill the crude solution - but at 91% it forms an azeotrope with water, so they have to use pressure-swing distillation or other more exotic methods to break the azeotrope to get anything above 91%)
ATTinyCore and megaTinyCore for all ATtiny, DxCore for DA/DB-series! github.com/SpenceKonde
http://drazzy.com/package_drazzy.com_index.json
ATtiny breakouts, mosfets, awesome prototyping board in my store http://tindie.com/stores/DrAzzy

jboyton

I should have soldered those few from the other side. Most of the connections I couldn't get to the opposite side because of components blocking the way, but those few were actually accessible.

I tried using some 70% IPA but it didn't really help that much. If it's only a cosmetic issue then I can solve that by using 12 year old 50% ethanol to improve how it looks to me.

The point was really whether I need to upgrade my soldering iron.  It doesn't sound like it matters that much. I'm about to try and solder a tiny 8-pin surface mount part (.65mm pitch) onto a board and I'm a little nervous about that. I have a narrow tip for the iron but I figure it's 50-50 as to whether I botch it really badly. I bought two chips and two boards hoping I'd get at least one attached successfully. We'll see.

dankgus

While I'm sure your Weller suits you fine, and I realize you love it and think its the best - to call the Hakko a "gizmo" is doing a disservice to the unit and the brand.
You are right, I should not have said that.

I have no personal experience with Hakko products.  My gizmo comment was based solely on the appearance of the station in the Amazon picture. I can be a jerk at times.

--Dan

weedpharma

In the picture, the pins marked Data and Vin are classic possible dry joints. The spherical appearance shows that the solder blob is only on the wire and not melted onto the board. It means that heat was only applied to the wire and not to the board.

A correct joint has the solder looking like a ski slope with medium slope.

Weedpharma

jboyton

#24
Mar 20, 2015, 02:48 am Last Edit: Mar 20, 2015, 02:49 am by jboyton
In the picture, the pins marked Data and Vin are classic possible dry joints.
Could be. Although I'm hoping it's just flux and too much solder that's giving that impression.

Here's a closer look (view the image itself for more resolution):







weedpharma

The pin marked "Clk" has a rounded base which is not a perfect joint.The pin DC is much better. The pin to the right of that needs alittle more solder.

All pins in the lower picture have too much solder.

Weedpharma

zoomkat

Just starting out and I know I will need a reliable soldering iron. Which one do you use? What wattage do you recommend as a minimum? Thanks
I've got a 15 watt RS similar to below and the fine tip works well on small parts and connections I solder. The tips wear out over time and replacement tips were always available at the RS store (not sure how many stores are left now).

http://www.radioshack.com/15-watt-soldering-iron-with-grounded-tip/6402051.html#q=soldering%2Biron&start=5&tab=tab1
Google forum search: Use Google Search box in upper right side of this page.
Why I like my 2005 Rio Yellow Honda S2000  https://www.youtube.com/watch?v=pWjMvrkUqX0

jboyton

The pin marked "Clk" has a rounded base which is not a perfect joint.The pin DC is much better. The pin to the right of that needs alittle more solder.

All pins in the lower picture have too much solder.
I know what it's supposed to look like. But what do you do, either as a beginner or an expert, when it isn't perfect. Should I heat it back up, pull the solder off with a solder sucker, and solder it again? Or would all the extra heat just add risk of damage to the board with little to gain except for cosmetic appeal. I mean, if the joint is suspect something needs to be done but are these possibly bad? I can't tell by looking or by testing them. And I know that there's something like a 50-50 chance my next try won't look all that much better. So what would you have me do? What would you do?

weedpharma

I would remove the blob, check that the solder pad on the board is clean and start again making sure that the iron is heating the board as well as the wire.

While learning, you will destroy solder pads from too much heat. That is why you practise on old boards.

It takes practice.

Weedpharma

jboyton

I would remove the blob, check that the solder pad on the board is clean and start again making sure that the iron is heating the board as well as the wire.

While learning, you will destroy solder pads from too much heat. That is why you practise on old boards.

It takes practice.
I'm a little nervous about practicing on working boards.

As a side project I wanted to play with a chip that, as far as I'm aware, is not available in shield form. It comes as a pretty small chip with 8 flat pads hidden on it's underside. I was optimistic, but my first attempt failed to produce a working part. And repeated attempts to improve the solder job eventually resulted in this:



You've probably seen that sort of thing before. :-)

I had hedged my bets a little by purchasing two of these boards (and the chips -- I torched the first chip too). And fortunately I got the second one to work, although it also took repeated efforts to get contact on all of the hidden pads of the chip.



One thing that really caused me grief was an inability to get the solder to flow easily and quickly. I did my best to keep the tip clean and hot enough, but still ended up with balling solder. I read about using flux but I have never done this and don't have any. Is it worth investing $7 in one of the flux "pens"?

Go Up