R

ron sterba

Well Known Member
Finding some of the wires in Dynon's Skyview 37 wire harness are not long enough to go to the fuel tank sensors. I'll have to splice in some 22 awg wire. Is there a preferred solder or solder flux combo? Diameter Size solder? I have the 25 watt iron.

Thanks Guys
Ron in Oregon.
 
Size doesn't matter. Or so I've heard. The .062 stuff is pretty big, though; I like to use something a little smaller diameter. The easiest to work with is probably 63/37 tin/lead rosin core. I'm using no-lead no-clean these days, but that's mainly because I ship a lot of stuff to EU countries and they care about it. If you only need a small amount and not the 1# rolls I buy, just pick up some rosin core at Rat Shack or the Lowes/Home Depot aviation aisle.

The one hard & fast rule is -- never use acid flux. Ever.
 
Solder

DaleB said:
Size doesn't matter. Or so I've heard. The .062 stuff is pretty big, though; I like to use something a little smaller diameter. The easiest to work with is probably 63/37 tin/lead rosin core. I'm using no-lead no-clean these days, but that's mainly because I ship a lot of stuff to EU countries and they care about it. If you only need a small amount and not the 1# rolls I buy, just pick up some rosin core at Rat Shack or the Lowes/Home Depot aviation aisle.

The one hard & fast rule is -- never use acid flux. Ever.
Click to expand...

Agree.
I have a 1/2 lb roll of .026", 22 ga, I've had it forever. I can't remember where I got it. It's a good size because it melts easy and I can unroll a bunch so the roll can sit on the bench. After, just roll it back up.
 
I like the smaller stuff for fine wire work too. Rosin core eutectic (63/37). I inherited some 2% silver I use sometimes.

Since you are asking the solder question, here is a guide for how to do the mechanical part of making a nice smooth solder joint from Aeroelectric. I like it better than the double hook loop method.

Splice

One thing is not shown and that is...if you are joining several wires, don't put the joints all at the same spot. Stagger them so that your harness does not look like a snake that just swallowed a rat.

That will help make the harness a bit more robust.

Good luck!
 
Bill,
Thanks for the link and the tip. Never heard of the "tease one strand out and wrap it around the joint" method. Will have to try that on my next model.

Ron,
After 30+ years of messing around with R/C models (and their 22-26 ga. wires), I also have found that smaller is better (well, with solder anyway). Like Wirejock, I also have a roll of 22 ga. solder that I've had for years. I got it from my Dad, who had also had it for years. At the slow rate I'm using it, I'll need a son to pass it along to... :D
 
The elfin-safety weenies in Europe have banned lead solder. I had an awful job trying to get the lead-free rubbish to flow properly. On a visit to the States, I got some proper stuff from Radio Shack .... :D

Oh, and its "Sol-der" not "Sod-der" - there's an "L" in it...........
 
Kester is a good brand. Soldering is pretty satisfying when you make a nice shiny joint. Also, fingers make terrible heat sinks, but sometimes you have to just suck it up, and hold the work together until that little blob of molten metal solidifies!
 
Another option

Instead of solder, use a D-Sub crimp pin and socket combination.

Add a small section of clear heat shrink over the connected pair to provide insulation, strain relief and holding the connectors together. If you ever need to break the connection just slice the heat shrink away.
 
I agree!

az_gila said:
Instead of solder, use a D-Sub crimp pin and socket combination.
Add a small section of clear heat shrink over the connected pair to provide insulation, strain relief and holding the connectors together. If you ever need to break the connection just slice the heat shrink away.
Click to expand...

This is by far the best solution. A good crimp is always better than solder.
 
Well I found my aeroelectric book late last night. After reading your great posts I headed to "ACE is the place" first! Then I found the info in the book on page (9-2). Found only 60/40 and none of the 63/37 but I think I was close enough. OHHH what a beautiful splice in solder I did and will have to do the Sub-d next. That smaller gauge solder .026" melted right away.The solder I had was a 90/10, not sure what 90/10 is. I think its was mostly silver. Took forever to melt and in most cases my fingers were the HEAT SINK! OUCH! I side with one of the other posters. Thanks Bill for posting that reference to Aeroelectric book under your word of "SPLICE". What a clever idea Bob has in his book. This book aeroelectric should be right along side of FAA 43.13. I like the encouragement of the sub-D connection by Gil and Mel.. Theres never a post between the two that I don't read. You two guys are my noteable heros when I feel I have up my head up my _SS! You know to present it straight forward HOW you did it and WHY. I think WHY is always best because it comes from experience!

In the book it says I can expect to buy in bulk at $9 a pound. I'am thinking that was a loonngg time ago. My 4 oz of 60/40 was $12 or $48 a pound but at this point in my build who cares! I want it at least be taxiing in the next 45 days under IO-320 power!!!

My question is about those BIG spade connectors from Dynon on the EGT & EGT probe wires. Can these be cut off and use the Sub-D splice connectors instead? I cannot see if a wire is 18 AWG that the spade connector need to be HUGE! Maybe I'am missing something here on connection of wires but thinking a nice pair of Sub-D and Heat Shrink for strain relief would be sufficient for the probe wires to the Dynon 25 wire wiring harness in the engine compartment prior to passing thru the firewall to the cockpit.

Always appreciate your thoughts guys!

RV9A N421HJ

Ron in Oregon
 
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Hi Ron,
60/40 is OK.

Aeroelectric talks about solder so when you finish re-reading it, you will be an expert. :)

The 90/10 and other mixes that are far away from 63/37 are designed to be workable in a plastic or paste stage for joining metal seams and stuff. They will melt but it takes a lot more heat than the perfect 63/37 that skips the paste stage and instantly melts (or freezes).
 
Mel said:
This is by far the best solution. A good crimp is always better than solder.
Click to expand...

Hmmm... please define 'best' and 'better'.

Crimps can be done by unskilled labor with minimal training and expensive equipment; soldering is an (easily learned) skill with very inexpensive equipment.

Crimps are much faster, and much more expensive.

There is no difference in quality of the finished joint between the two methods, when both are done properly. An improperly executed crimp and a 'cold' solder joint will both result in an eventual failed joint. (And no, the wire is *not* more likely to break outside the joint when soldered. Both types of joints have 'stress risers' at the point where the joint transitions from rigid to flexible, and wires from both must be supported near the joint.)

Charlie
'professional' electronics tech in two different previous lives (careers) who has repaired many cold solder joints and many bad crimps (in many cases, in multi-hundred-thousand-dollar industrial equipment built by 'professionals')
 
Mel said:
This is by far the best solution. A good crimp is always better than solder.
Click to expand...

Environmental splices are my favorite choice.

[PDF]Wire-to-Wire Splicing - Raychem
raychem.te.com/documents/webservice/fetch.ashx?fileid=8460&docId...
ing products offer solutions for hundreds of aerospace and defense applications. These environment-resistant splices provide excellent reliability, long term per-.
 
Mel said:
This is by far the best solution. A good crimp is always better than solder.
Click to expand...

Exactly. That is why we used crimp splices during my 29.5-year aerospace career. A solder joint can get brittle and break from the vibration if not done perfect. A good crimp connection has less failure modes than the solder. Yes I was space flight solder certified and will take the crimp over the solder splice.
 
RV6_flyer said:
Exactly. That is why we used crimp splices during my 29.5-year aerospace career. A solder joint can get brittle and break from the vibration if not done perfect. A good crimp connection has less failure modes than the solder. Yes I was space flight solder certified and will take the crimp over the solder splice.
Click to expand...

I've got a little experience myself. 41 years building stuff for Texas Instruments and 6 years USAF avionics tech.
I'll still take crimps.
 
I only have a little experience... solllllldering for 42 years. So why do those RV guys across the pond notice if we have an L in our solder whilst we are typing?
 
I too was NASA flight solder certified.

I can't imagine an RV going through more vibration and stress in its lifetime than the tremendous forces a satellite goes through on liftoff. If it does, well you've got bigger issues than a solder joint and we'll all be in sorrow for your passing. However, I don't claim to be an expert nor did I sleep in a ... It's only a guess on my part (notice I left out the word intelligent).

It would be nice to see some empirical testing to the age old question: tip up or slider, I mean, solder or crimp?

We used the 63/37 ratio. I was told it was easier to get a good joint, using that ratio, than the typical 60/40 used in the day. Any way, I found that before being certified I only thought I knew how to solder. Looking back, the soldering I did before I went through the certification training probably created mostly bad joints. Even when I was in the Air Force we were never taught proper solder technique (and I worked on missiles and aircraft electronics there as well). Everyone talks about good technique but there are few resources to get you there.

Hence...here is a link to some NASA video's on solder technique. As with anything its not the quantity of the solder it's the quality of the soldering. It really doesn't take much solder to get a good joint.

http://radiojove.gsfc.nasa.gov/telescope/soldering.htm

Bob
 
Man O man you guys ARE GOOD! I can read that whole book on Aeroelecric but really not understand it. When Iam hit with a problem and have to read the chapter over with the variables at hand, there's that LEARNING CURVE that follows! You are my classmates and instructors,why being on VANSAIRFORCE FORUMS is so important. You get that first hand knowledge and HANDS- ON experience. OH, I really like the crimping style best!

Another question. I am going to post next is where did you put your Transponder,ADSB and com antennas? Where they just mounted through the fuselage skin OR did you use a backing plate riveted to the fuselage ?

Thanks to ALL who posted here,I LEARNED a lot the last couple of days!

RV9A N421HJ
Ron in Oregon
 
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Hello Mark. I have come to the conclusion I will use solder in straight line wire runs. strong and economical. I see where using the Molex connectors with heat shrink is a viable way to go too. I feel now that both methods have their place in building,its just the environment the wire run is in and the vibrations associated with such a location. Its been a GREAT dialog with the builders!

Now I agree that the solder joints are strong. Ask me how I know! I used the hook method of splicing a in-line splice. I made a small smooth bend and came back over the wire with the one wrap around itself and same with the other wire and gently made the splice stream line.With a little flow of 60/40 solder I was finish,,,NOT,,,,,,forgot to slip heat shrink tubing on first. So I heated the splice drew off as much of the solder but STILL could NOT pull the splice apart! Glad I built in a ERROR FACTOR! Cut off the splice and started over. Now I DO LIKE Bobs (Aeroelectric Book) of the PULL A long STRAND OUT (1 ") of one wire and trim both wire ends to 1/4" or so,lay side by side and then lashing both wires together with the LONG strand to keep it tight. It was mentioned with a website lead to the book example in a above post. Again ALL BUILDERS SHOULD ORDER THE BOOK (AEROELECTRIC ) FROM YOUR FAVORITE AERO SITE OR EAA'S WEBSITE STORE.

Thanks Mark,
Ron in Oregon
 
As I understand it, what we are striving for is a gas-tight, mechanically sound connection, and crimping (done right) achieves both, and I did 98% of my connections with crimps. Where I tended to use the solder splices involved small wires (24-26 AWG) or areas where a butt splice took up too much room or where I was daisy chaining grounds for the avionics (per Stein's excellent videos). They're not cheap, but I love em for what they do.
 
I agree Stein's Videos are the place! Hey Mark at the bottom of your page about TOO STUPID TO QUIT. A friend of mine started his RV9A at the age of 86 and just finished it at his age of 92 with Advance Displays. Gilbert is amazing man! I believe it keeps your mind youthful when you are a builder. It flew last fall and was posted on Vans website. OHHH ,it was a slow build kit!

Ron in Oregon
 
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