Solder vs. Crimp - Part 3 - Feeling Scientific

[chuckz]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Wire wrap boards for space applications, boy you are an old timer.<br /><br />Seriously, I saw a lot of wire wrapped boards. I supervised the final test department for a company that made state of the art video titling equipment. All the boards were wire wrap technology. I hated the technology because it created more problems then it solved. I don't remember ever seeing final space hardware that was wire wrapped.

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

These were one of a kind systems so wire wrap was the way to go. <br /><br />Like anything though, it has to be done correctly. A high quality board, wire, thermal strippers, automatic wrap gun, careful routing and wrap order. If it doesn't look pretty it isn't done right. <br /><br />Then, you have to sit and ring out every connection before you even populate the board and begin testing

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Ah Ralph, the $70 crimper. Costs more than my fish finder. I would say that is ideal for a shop who does hundreds to thousands of crimps in a year or the man with the budget for the best tools. For those of us who cannot afford the best tool for the job we are seeking best solutions for what we have. I take the sears crimper I have and squeeze till my knuckles crack. As you said, better solder it.<br /><br />Sinse we are throwing out qualifications here: As for me, I am a senior computer engineering student(damn close to finished.) Worked 2 years in electrical supply and moonlighted as an electrician's assistant the whole time. Also worked as an electronics installer for a boat dealership for 6 months(I used crimp there, solder took to long for the volume we were doing.) Also did several years as a computer network installer before that. Other than that, farm boy all my life. Rebuilt my first motor when I was 14. Do it yourself is my philosophy. Dosen't necessarily qualify me near as much as a EE or a pro who has worked marine electrics for a decade, but dosen't mean I can't prove a point and have a little fun doing it.<br /><br />BTW I am in the never-ending project of refurbishing a 1979 Terry Bassboat with an original Johnson 115 v4 and outfitting it for better flats fishing in everglades nat'l park. Twas my dad's old boat(who passed away 6 years ago) and hasn't run in over 15 years till last year. Its been to the flats several times this year and has caught many fish. Good budget project I think. Its not where I want it yet, and it improves as my budget allows. Soon, smart tabs...

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Never heard of wire wrap myself, sound interesting Ralph.

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

redmopar, you can get double ratcheting crimpers for as little as $20 - I am pretty sure Autozone carries them for that price. You pay a premium for Ancor's. I have Ancor's and a pair made by Paladin (I think) that I paid like $30 and there isn't any difference per se.

 

[Paul Moir]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Originally posted by redmopar:<br /> Never heard of wire wrap myself, sound interesting Ralph.

Some things are best left forgotten.

 

[chuckz]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Most of the time wire wrap was used for one of a kind and prototype developement.<br /><br />The boards I used were wired by computer automated wiring machines and the final boards were tested on bed of nail testers. We had problems with new boards and field service was worse.<br /><br />As computing speed increased, wire wrapped became less pratical. The posts the wire was wrapped to was about 3/4" tall. At high frequency they become antennas. Wire wrap boards generate lots of noise and are much more susceptable that PC boards.<br /><br />Paul said it best.

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Ralph, didn't find them online at autozone. I'll be checking out the store later. Can't resist that deal. Thanks.<br /><br />Thanks for the info Chuck. Sounds diffucult.

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

red,<br /><br />Hurry only 2 left!<br /><br /> http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=26449&item=4509321914&rd=1

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Normally I wouldn't spend that much on crimpers, but what the hell. I bid on em. Not likely to win at $36 though. Thanks Ralph.

 

[clanton]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Kline,20.00 home depot, will handle most small boat wiring. Quality of connectors realy important.

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Clanton, I appreciate the effort. I used to sell Klein tools at the electrical supply and I think you are reffering to the standard plier-type which sells for around $20. I'm looking at more like what is pictured above by Ralph, either a ratchet-style or scissor style which I beleive the only one they make is a mil-spec ratchet crimper but it runs about $180 and HD dosen't carry. Never sold one, but I got asked about the price a few times. Tiz why I never sold one. Could be wrong though as I haven't sold klein in a year or so. Did sell a couple of Ideal ratchet crimpers. $140 well marked up as we didn't carry Ideal. HD carries Ideal, but I doubt they have those too. As for conectors, i'm off to westmarine here to score some Anchors.

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Score! Found another one. $20 Harbor Freight Tools. What I like to refer to as the "Good Crap" store. The sizes are not listed on the website, but it is 10" so I assume it is for the sizes we need.<br /><br /> Ratchet Crimp Tool

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Red - that's a single. You want a double

 

[redmopar]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Ah, true. Don't think it would be acceptable to crimp twice for our experiment purposes? Only assuming ebay falls through that is.

 

[jlinder]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

L.I. Chuck,<br /><br />Pretty sure I know the company you worked for that did video titling. Starts with a C, right? I worked with the model IV units. Always scared to touch the boards. Amazed that the ones on mobile trucks worked at all bouncing around. And don't forget about the gazillion pound power supply (300 AMP @ 5v ????).<br /><br />Did wire wrap myself. Glad it is now history.<br /><br />Agree with opinion of crimping. Done right (good crimps and proper crimpers) nothing better. Done wrong (pliers for example) not worth a damm.

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Red, <br /><br />for $20 you can get a double at Autozone even if eBay fall through. Might as well get the right one... The high quality insulated terminals fit perfectly in the die for the double crimper which makes it virtually fool proof... the barrel on good terminals are much longer than the cheap ones because they are made to take a double crimp.<br /><br />Jack,<br /><br />Not only will they survive bouncing on a truck but they will survive outer space and back. Of coarse I am talking about the good stuff like Augat boards which even back in the early 80s were like $500 for like a 8" x 10" board...

 

[swist]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

When you look at it wire-wrap is kinda like crimping with the terminal and the wire reversed. A purely mechanical connection whose integrity is based on the outer component gripping the inner component tightly. I wouldn't wire wrap in a boat, and I wouldn't crimp without soldering either.

 

[Ralph 123]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

No one is talking about wire wrapping on a boat. Wire wrap was brought up to show how strong proper mechanical connections can be and because a challenge was laid down to ask a paid professional (which I am).<br /><br />I did a little digging this morning and here is what I can share - again, we need an ME who works in A&D or marine industry to opine.<br /><br />The problem with soldering is that, being soft, it cracks under the constant stress of thermocycling and vibration (which boats experience in spades). In fact, there is a study ongoing by Prof Subramanian at MSU:<br /><br />

Electronic solder joints undergo repeated thermal cycling during service. They may also experience mechanical vibrations. The solder joint reliability is significantly affected by such service conditions. Current focus of the project is to evaluate microstructural evolution and its influence on the life of the electronic solder joints. The main aim of the project is to develop suitable models for reliability predictions of lead-free electronic solder joints. <br /><br /> http://www.chems.msu.edu/php/faculty.php?user=subraman <br /><br />

The other issue with soldering is that it will wick up the wire during soldering making the wire hard in the area it connect to the terminal, thus increasing the chance that under prolonged vibration, the wire will break. This is the same reason solid wire can't be used on a boat and the finer the strands, the better. NASA required steps to prevent wicking if soldering is used on a connector (terminal).<br /><br />The NASA Spec for crimping can be found here:<br /> http://www.hq.nasa.gov/office/codeq/87394c-8.pdf <br /><br />A study of pull testing of crimped connectors can be found here:<br /> http://www.wiringharnessnews.com/Articles/Pull_Testing.pdf

 

[18rabbit]

Re: Solder vs. Crimp - Part 3 - Feeling Scientific

Redmopar – I think 4 scenarios for your Patriot Act challenge:<br /><br />(1) solder only<br />(2) solder and crimp<br />(3) proper double crimp<br />(4) two single crimps (double?) like you would expect to find if someone were to use a cheap single crimp tool trying to get a double crimp.<br /><br />I’m thinking the results for (4) is going to have the most value.<br /><br />EDIT: after you are done with your finals, if you let me know what you need for (3) I can make up some samples and send them to you. Also, if you’re not concerned about color, I can send you some conductors. I have a bunch of Deka brand type 2 marine wire (AWG 16, 14, 12 - red and yellow and AWG 12, 10, 8 – white, black, green). There’s also a bunch of Ancor type 3 AWG 16 in all those pretty colors. Whatever you decide, I suggest staying with the same make/model/size conductor and connectors to assure uniform detonation of your O2 chamber.