Smallest resistors and other basic components?

[gavino200]

I have the regular small 1000 Ohm resisters for wiring in series with LEDs.

 

http://www.ebay.com/itm/1000pcs-set-1-4W-50-Values-1-to-1M-ohm-Carbon-Film-Resistors-Assortment-Kit-F0D5/162304444288?_trksid=p2045573.c100508.m3226&_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D38530%26meid%3D1aa8a8d9100d4295b45142203858b655%26pid%3D100508%26rk%3D1%26rkt%3D1%26

 

These are fairly small, but in n-scale they are humongous. Is there a resistor available that is smaller in size?

 

Same goes for capacators. The 220 micro Farad capacitor that Soundtrax give with their decoders are giant. Is it possible to get smaller ones?

[cteno4]

Gavin,

 

You can go down to smd resistors that don't have leads

 

1/16w tiny 402

 

http://www.ebay.com/itm/0402-SMD-Chip-Resistor-5-180-Ohm-33K-Ohm-options-100pcs-/182341653735?var=&hash=item2a7468d4e7:m:m63RETrskyu56ggEJUXB9YQ

 

1/8w 603 and 805

 

http://www.ebay.com/itm/100pcs-1K-1000R-0603-8P4R-SMD-networks-Resistor-4-rows-8-pin-SJ203-/302004424025?hash=item4650ddcd59:g:u1gAAOSwniRWOFZR

 

http://www.ebay.com/itm/100pcs-0805-1-8W-SMD-Chip-Surface-Mount-Resistor-1KO-1K-ohm-102-5-/131915362637?hash=item1eb6c4b14d:g:FMIAAOSwV0RXuU4X

 

1/4w 1205

 

http://www.ebay.com/itm/1206-SMD-Chip-Resistor-5-220-Ohm-56K-Ohm-options-100pcs-/182342667962?var=&hash=item2a74784eba:m:mJHW3ykmQm_4BHhHFb3atjA

 

Larger numbers mean larger size

 

http://www.resistorguide.com/resistor-sizes-and-packages/

 

Tantalum brick caps are about the most dense you can get. They get expensive why you get to higher uf and 25v to be safe

 

http://www.ebay.com/itm/20pcs-Tantalum-Capacitors-227E-25V-220uF-Type-E-SMD-7343-Surface-Mount-/322335650799?hash=item4b0cb3b3ef:g:m~sAAOSw44BYMxmL

 

Jeff

[gavino200]

Awesome. Thanks :)

[HantuBlauLOL]

go for SMD components. 

[cteno4]

Most components come is a smd (surface mount device) format that are tiny and no leads just those solder pads. Usually they are lower power than the lead forms as they are tiny and meant for low power circuit boards.

 

The big issue is soldering them. It's not super easy but can be done with some practice. You need a very sharp tip and a good temp controllable soldering iron. Next challenge is holding things in place while soldering. I tend to use upside down painters tape to do this. I tape a piece of blue painters tape to the bench sticky side up. You can then place the components and wires down on the tape to hold them in place. Painters tape holds things well enough but allows some repositioning and the adhesive does not get gummie around the heat and the backing doesn't burst into flames.

 

I then use a pin to place a tiny tiny dab of flux on the joint and hit it fast with the iron. I usually tin wires first so that the wire does not tend to then suck the solder up first or with magnet wire it removes all the enamel from the solder area so it doesn't contaminate the joint soldering process. Very thin solder also helps to melt fast and get Into the tiny joint as well as not block all your view of the action!

 

With smd LEDs you can solder the smd resistor off one side of the LED if you want the. Attach one lead to the resistor and led.

 

There are a few different ways to skin the cat on this, take a look at YouTube for some good how to videos.

 

Magnification is also a must and I find the lighted magnifiers on a swing arm work best for this task.

 

The bad news is it's a fiddly process that is not everyone's cup of tea. Good news is the components are pretty cheap so if you like the challenge and or have the need then with some practice toasting some tossers you can do it!

 

The tantalum caps are easy to solder as thise are much bigger. Also caps in parallel are additive in value so you can solder a few smaller ones together to make a bigger one. With the little tantalum ones it's easy as you can just line up a few side to side and solder a lead (use a small resistor lead, I bought a 1000 on ebay that had very fine leads at what ever value once for 50 cents at auction to just use for leads like this on proto boards) down each side. This helps as getting the 25v (to be safe with 12-18v of dcc) ones gets expensive in the tantalum caps. These are great to help light flicker in lighted cars and such as you can make a flat pack that can be hidden better than an electrolytic cylinder cap.

 

Jeff

[gavino200]

Thanks for such a helpful response.

 

I like the tape idea and will use it. 

 

My iron is a 30W non-adjustable. The tip is fine but not very. I like to use basic tools until I hit a wall and need to upgrade. I fried an LED yesterday by soldering it onto a wire, so I think I may be using too much heat. I'm planning to hit YouTube to school myself. Also, I taught my son to solder yesterday so, I owe it to him to learn more, so I don't pass on bad habits. Is there an iron that you like/recommend? Also, is there an online soldering supplies store that you recommend?

 

I decided yesterday that I don't like lead free solder. I seem to find the old stuff easier. Am I right about this or am I doing something wrong.

 

For mag I use a pair of Zeiss 3.5x wide angle loupes. I actually got these for free, and I prefer a different brand, so I use them for hobby stuff.

 

https://www.zeiss.com/meditec/us/products/plastic-reconstructive-surgery/loupes/eyemag-pro.html

 

I find these very helpful. When you get used to them you don't even notice them. You switch between mag and non-mag without thinking. And you can flip them up if you walk away. They are ridiculously expensive, but you can buy very cheap versions by no-name brands now for around $250. If you're interested I could find you a link.

 

The fiddliness is not an issue for me. I'm a microsurgeon. I'm used to sewing 1mm vessels under an operating microscope. So working on tiny parts is kind of fun for me. I'm a novice working with non fleshy stuff though. 

 

Again thanks for your help.

 

Gavin

[kvp]

Unregulated 30W is good for heavy wire work, but not really for anything N scale (decoders, leds, etc.). The idea of a regulated iron is to supply just as much power as needed to keep the right temperature. Lead free solder only flows at certain preset temperatures, so if your iron can't stay in this band very precisely, then the solder wil either not flow or evaporate on contact.

 

I would suggest a smaller (like 15W or so) temperature controlled soldering iron with a very fine tip. It doesn't have to be expensive, any small 20-30 usd temperature controlled iron will do, they just tend to break more easily. Using a wet sponge for cleaning the head and doing it often makes soldering a bit easier, also using thin, no clean rosin core solder for small parts. (also try to avoid acid based flux at all costs as most modern parts don't like it)

 

ps: one more tip for soldering to printed circuit boards: a tiny drop of ca glue can fix a part in place until you solder it in, just be careful with the fumes

[cteno4]

Gavin!

 

Ha so you are totally use this stuff then! You will have no problems,mjust some practice to get the whole thing down.

 

Yeah I have mag visors as well, but for the soldering I like the big glass as looking away to deal with soldering iron and grabbing tools (no nurse there to hand them to me, hey that an idea!) I like not having to move the visor all the time. Basically what ever works best in the situation for you! Some have issues looking thru the large magnifiers and some ththe the visors as well so again it's what works best for you.

 

That's the cool thing with the smds, they are cheap! Fry a few dozen figuring things out and practicing is no worry at all! Can't do that on patients, but you can here!

 

Yes get yourself a little controllable iron that has a good range of tip possibilities. Nice ones can be had for $50-100. I've used very expensive ones and they are nice but for doing a little work like this a decent one works fine.

 

https://smile.amazon.com/F2C-862d-Soldering-Station-Accessories/dp/B013DQQ4XO/ref=sr_1_17?ie=UTF8&qid=1484679396&sr=8-17&keywords=soldering+iron

 

Those squeeze forceps also are handy for small soldering.

 

These can be handy (you can get simpler ones cheaper)

 

http://www.micromark.com/triple-grip-third-hand,6736.html

 

But this is the one I love and you can make your own that's more flexible for a couple of dollars. You can get microclips that you can grind into small points or use micro probes to hold wires. Just take a hunk of wood and drill a grid of holes to hold the wire ends where you need your clamps for the job.

 

http://www.micromark.com/4-arm-holding-jig,7173.html

 

Hair clips as well are handy light clamping clips that can be ground down on the end to custom shapes.

 

http://www.ebay.com/itm/10pcs-Single-Prong-Alligator-Steel-Pinch-Clips-for-Hair-Bows-Corker-Silver-/301692782795?hash=item463e4a88cb:g:~G0AAOSwA3dYY1If

 

Yeah the non lead solders can be cranky! I tend to stick with the lead solders as I use so little on most things and it's sealed up and not something you will be touching or sucking on! Fumes can be a worry but with a small fan that's not a huge issue as very little lead in the fumes so dilutes fast, but the flux fumes are more a worry. If you want to trap them more these little units can suck away the fumes at filter out most of the crap onto an activated charcoal filter. But even a little PC fan sucking the fumes gently away is a big step forward!

 

http://www.ebay.com/itm/1000L-Solder-Smoke-Absorber-Remover-Fume-Extractor-Air-Filter-Fan-for-Soldering-/182408717589?hash=item2a78682515:g:DM8AAOSwImRYa1dQ

 

Problems with the tiny soldering is you tend to get your nose right in there close! Distance focusing visor keeps you back more and the larger magnifiers act as a bit of a barrier as well for fumes.

 

Cheers

 

Jeff

[gavino200]

You're right. We're totally spoiled. I'm used to having one scrub tech pass me instruments, and another holding and retracting. I tried asking my wife to do this a home, but she was having none of it. :)

 

I already have a "third hand". Mine is a Harbor Freight special. I love the "4 arm holding jig". It looks very useful. I'll order one. I also like the hairpin idea. I've been using bulldog vascular clamps but they're too strong. I'll be making another trip to the beauty isle at the supermarket. I already picked up some make up brushes based on a thread in the tools forum. Got an interesting look from the cashier. 

 

I'll pick up a solder fan. I smoked for many years but the little dude's lungs are clean. Better to keep them that way.

 

That soldering rig is amazing. It's fairly cheap too. It would also be nice to have a heat gun. Thanks. 

 

Regarding the loupes. You might want to reconsider them. They're a little different to the visor. The mag lens is small and right in front of your pupils. So you can look over them and through the clear/prescription lens with just a slight movement of your eyeball. It's like wearing bifocals. After a few days you don't even notice them.

 

 

The distance takes some getting used to. However it allows you to sit with a straight back and relaxed shoulders which is key for steady hands. The other trick is to not "float" your hands, but instead, rest them on some folded towels or cloth. That eliminates the small amount of physiologic tremor that everyone has. You do all the work with your fingers rather than your hands. If you do this you can maintain absolute steadiness for hours (for me, up to 12 hours). Relaxation and breathing control helps too. 

 

This is a pair that I found with a quick search. If you're ever interested I could ask around. I know a couple of people who tried out cheapie loupes. Reports were positive.

 

http://www.ebay.com/itm/3-0X-Medical-Galileo-Loupes-Surgical-Binocular-Loupes-3X-Dental-Magnifying-420mm/252165460148?_trksid=p2045573.c100507.m3226&_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D38530%26meid%3D0c878872b33745549e4b9945d21fa099%26pid%3D100507%26rk%3D1%26rkt%3D1%26

 

 

Forgive me blabbing about magnification. That's one thing I know well. In all other regards, I'm the humble apprentice here :)

Edited January 18, 2017 by gavino200

[cteno4]

Gavin,

 

no great stuff to hear from the ultimate expert in it! you can provide a lot of expert info on this sort of stuff.

 

ive a few cheap loops like that but most dont give any peripheral vision or cover the whole lens. these like you say focus directly on

 

bending over the mag glass is something i try to resist and set it up so im not leaning over it looking straight down.

 

I may have to try a pair of these for the longer sessions!

 

keep your lungs good as well as the little one!

 

4 hand can easily be made. i dont like the small base of the micro mark one, i have a hunk of 3.4" ply i just drilled a grid of holes in. 14g romex wire scraps and then alligator clamps, hair clips, magnets and even a pin to hold things in place by poking them. i need to write up a little how to on this one as its super simple and cheap.

 

loads of soldering irons out there that one just popped up cheap on amazon. heat gun is nice to have a smaller one for doing heat shrink than a big hair blower style. i just got a small smd rework heat gun just for this lately.

 

Ha you got the bug now of lurking the dollar, grocery, drug stores for useful little bits. yes you can get strange looks! Nail stuff also has a lot of bench uses as well!

 

cheers

 

jeff

[gavino200]

 

 

4 hand can easily be made. i dont like the small base of the micro mark one, i have a hunk of 3.4" ply i just drilled a grid of holes in. 14g romex wire scraps and then alligator clamps, hair clips, magnets and even a pin to hold things in place by poking them. i need to write up a little how to on this one as its super simple and cheap.

 

loads of soldering irons out there that one just popped up cheap on amazon. heat gun is nice to have a smaller one for doing heat shrink than a big hair blower style. i just got a small smd rework heat gun just for this lately.

 

 

 

 

Yes, a write up on the 4 hands would be great! These things are nice to have but even more fun to make. I wondered about toppling when I saw it. I figured I'd have to glue it to a wider board.

 

I'm going to research soldering irons carefully. I had expected a variable iron to look like a regular iron with the addition of a tiny knob to change the voltage. That unit looks very nice. I do have a preference against combined units though. So I'd look for good iron that's just an iron, and a good heat gun that's just a heat gun. 

 

As always, thanks for the advice.