Learn me some soldering!

[wanabgts]

Hey guys, I have been slowly building up my skills at scratch building. I am making good progress overall.

I recently switched to thinner solder, which helped a lot with my flow and aesthetics. But the soldering Iron I have that performs well on sheet brass has a pretty bulky tip, resulting is some blobs at times.

What soldering Iron do you use? What thicknesses of material do you do with it?

What kind of Flux are you using?

Thanks for the help guys!

Zack

[HomeRacingWorld]

[chrisguyw]

Hi Zack, The "blobs" are not fault of the iron tip,...but, may be the wattage of the iron (heat), or, incorrect flux.

As Harry states, regular 60/40 solder will work just fine with all your 1/32 slotcar needs.....chassis building/electrical contacts. (60/40 has a lower melting temp. than silver solder, and is more than strong enough for the cars/motors you use,......zero need to use anything more exotic).

An iron with 45 watts and a 1/4 chisel tip will also work for anything you are likely to build, electrical included. A 45 watt iron with a 1/4 chisel tip has built more chassis over the years (1/32 and 1/24) than any other iron/tip combo.
It is critical to tin the tip, and clean it on a regular basis......tip tinning/cleaning paste is available at most decent electrical shops.

Flux.......for electrical contacts, Rosin paste flux is what you need, and for chassis building, Liquid acid flux is a godsend. Liquid acid flux etches the metal, and will let the solder flow into the joint. DO Not, use acid flux on any electrical joint :naughty: , and you will need to scrub your chassis work with an old toothbrush and some Ajax/Comet cleanser after soldering.....if you don't scrub your "acid" joints (you have 30/40 mins.) they will corrode/rust. :scared-eek:
"Stay Clean" and "Lucky Bob's" are the two best liquid acid flux products to use, and are sold at most commercial slot shops, and, online. Brush some onto the join, and solder away.

I am sure you know this but, as in Plumbing repairs, top notch soldering requires that the joint is heated and melts the solder....it may take a few seconds more but the results are worth it.

Hope this helps, and , If I missed anything, sing out.

Cheers
Chris Walker

PS..I missed a crucial point, (likely the most important point)....it is imperative that all wire/brass is surgically clean, so clean each bit with an SOS pad/800 grit paper to remove all oils/coatings.....solder will not flow/attach to any "dirty" surface

[mattb]

Stay Clean flux is the first step to a clean, smooth joint and I believe it is what Lucky Bob put in his little bottles. You can buy a big bottle of stay Clean on ebay for $7-$8 and have enough to last a life time or to fill up several hundred of those little bottles. I use a Hako, but any iron works fine if it 30 or more watts. Keep the tip clean ad Harry has shown on here with a Chore Girl or similiar type scouring pad. I also use a regular paste flux. If soldering a big piece of brass, like 2" X 5", 64k thick. I usually use a little butane torch. It heats the whole piece in a hurry. You will mess up everything if you try to use a torch for small work, stick to the iron for that.

I'm only fair, but my stuff doesn't fall apart. I use a wire wheel to clean and then an SOS pad when I am done,

[wanabgts]

Things I have been doing right:

Cleaning well all components
Using rosin flux, although its a past and seems to be work OK.
Tinning the tip and keeping it pretty clean.

I think a 1/4 tip would suite me much better for this work, Harry are you using the 80 watt version of the iron you posted? I also think cleaning the iron better between joints would probably help. Some of the blobbing is because of residual solder on the iron I believe.

I am not a newby to soldering, I do electrical all the time in automotive applications. Just getting a good clean brass connection has been difficult!

Thanks for all the input and links guys. I'm gonna keep working on it!

Zack

[Kevan]

Avoid new fangled 'low temp - lead free' solder like the plague...it's CRAP! Good old fashioned 60/40 is so much nicer to use.

[wanabgts]

[waaytoomuchintothis]

Well, I guess its too late now, but if you want quality soldering, go with a Hakko Soldering Station. Throw away anything else you have, you won't need it.

[mattb]

#1 Stay Brite flux

[model murdering]

Soldering is easy. You sit on yer butt. You heat the joint patiently. When it is hot enough you feed the solder in.

As with all things, the devil is in the details. Getting things to the point of soldering is the actual work.

Fitment is everything!

Frequently over looked is how your project is actually constructed. Poorly planned joints, or a series there-of, is just asking to get bit. I like to use captive or interlocking jointing via key holing, collets, shouldering, pinning, slots, ledges, lips, or troughs. I avoid common or free abutments like the plague. Naturally, mechanical jointing takes extra time and effort.

The upshot is that it helps when one is clamping and jigging modules, and assembling the modules into the whole. Assuming you keep the tolerance close, your bulkheads, cross members and frame connectors slide right into position on the frame rails. This also pays some dividends with the heat transfer across the joint. Flopping bits cannot be soldered. Impinge joints, with good physical contact between the pieces, will suck liquid solder in like a vacuum. Additionally, by using captive jointing, cross measuring and any subsequent minute adjustments can be nudged in without fuss.

Soldering is a physical process. Regardless of what one uses as a build substrate, ceramic jig, wooden buck, or free hand; one has to be able to lean on or into the project with the iron, in order to put sufficient heat into the joints quickly ... AND have that heat transfer efficiently across the pieces. If your project is scooting away, or the parts are wiggling around, you wont be happy with the results.

I also plan for run off or run out. It's not a perfect world, and shyte happens. I prefer to leave a way out for excess solder to drip or flow off neatly, rather than gobbing or wadding under the jig, or buck. While we dont want to, occasionally one has to over feed (washout), or re-heat a joint to get the solder to wick down satisfactorily and lay down clean. Consider that its easy to exceed the rating of a small iron by over feeding an area. Ideally I want enough heat so the solder can flow in and out of the joint uniformly, like warm syrup. By planning ahead, you might not have any major clean up, or at worst; a kiss with a fine file and some 600 wet dry.

Truth be told, I spend a good bit of time thinking it out, a bunch of time prepping it, and just a few seconds soldering. :auto-driving: