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RV-12 Wiring

C

climbingduo

Member
We are trying to Crimp Molex Micro-Fit pins ES-00047 for the trim servo wiring. Have been trying to use the tool we got from Avery . . . seems too big for these newer style micro-pins. Would love any suggestions on a better tool to use to crimp these. Directions all seem to be for the older style/larger wire and pins. :)
 
We have watched this. Unfortunately, the problem is that these wires are so small that we have set up a magnifying glass to work with them. The tool we have from Avery seems oversize since it is flattening the terminals, rather than rolling them.
 
I have both the GC/Waldom and Sargent crimping tools and they are both too large for the Molex micro fit pins. The trim motor wire is 26 gauge. I used surgical loops and a razor blade to strip the insulation and did my best with the crimping tools.

I did a pull test and practical test using the quick connection and then touching the forward end of the wiring to a 12 volt motorcycle battery.

JAL
 
Yep . . . we got the GC/Walden from Avery and it definitely appears too large. Hence are hoping to find something that will work on these "miniature" wires . . .
 
climbingduo said:
Yep . . . we got the GC/Walden from Avery and it definitely appears too large. Hence are hoping to find something that will work on these "miniature" wires . . .
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I don't know if you have a Fry's Electronics near you but I noticed they have a bunch of crimpers for network and related gear. I didn't get one yet, but that might be an idea.
 
I would expect that some people might replace these with something like a 9 pin D-sub connector. After certification is complete, of course. Micro Molex seems pretty minimal as far as connectors go.

Bob
 
same here...

I was going to post on the subject having determined that the Waldom crimping tool I received in the tool kit dangerously fat for these tiny terminals. I hoped to find a solution here as some have no doubt been through the same quandary but no luck so far!
 
txaviator said:
Radio Shack or Frys Electronics? Or I could darn near guarantee that you could buy a micro crimper online through Mouser Electronics.

Update: yep, Mouser has them....at a whopping $324 each! Gulp!
http://www.mouser.com/ProductDetail...GAEpiMZZMtArvHj40ttL9FpL0cXLG70%2bTyxQVcJFPQ=
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Found the $324 crimper too, deemed it absurd to buy it for a total of 10 terminals to crimp, although another way to look at it is $32.40 per terminal, peanuts compared to the cost of the Rotax! :D
On the other hand and in the same line of thinking, at 100HP the cost per HP of a Rotax engine ain't that bad!
 
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bhassel said:
Would those same people solder or crimp? :D
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I would guess that a large part of that group might solder. Soldering is more of a problem where vibration is present. I doubt there is much inside a nine pin D-sub connector with the wires being clamped down. I used some of these on my 9A years ago and have had no problems.

Bob
 
Let me see if I can find one a little cheaper in price than the $324 version. If I can, I will gladly buy one- then we can rent it out amongst us -12 builders for say, $30 per plane/builder? Just an idea...
 
IT seems to me like some of you are just looking for ways to add time and dollars to your project ! Are you afraid you might actually have to fly it some day?

On all my planes I just soldered the wires together with shrink wrap over it. Quick and inexpensive and never had a problem. If you ever have to disconnect it ( and I never did) just cut and redo it.
 
Got it done!

I noticed that my regular crimper was the same width as the two tongues to be crimped so I did both crimpings in one shot. It worked. The trickiest is to strip these tiny ends and position the insulation correctly as only 1/16th of an inch need to be crimped. I'm lucky I still have good eyes at "umpty"!
 
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small connector pins

I just bent the tabs close to the pin over with a small set of pliers and soldered. I then bent the outer tabs over the insulated part of the wire. Seems sturdy enough for me.
 
I've just done these using the two smallest jaws on Steinair's SAT-18 ($31) open barrel crimper as per the instructions in Section 5. I was a bit doubtful when I looked at the size of those tiny pins, but they actually worked fine.
 
Solution found!

Solution found! Agreeing with one of the previous posts . . . talked to SteinAir who supplies the wires and micro-mini pins to Vans. They sent us their SAT-018 Open Barrel Crimper (about $31) and we got a set of male and female micro mini pins to practice on. Worked like a charm!

Hint: set up a large magnifying glass on a stand in order to see what we were doing!

Happy crimping!

On a side note: 4 weeks building empennage kit; wings kit coming today!
 
sandpiper said:
I heard at EAA today that new kits from Van's come with these connections completed. Any truth to that?
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One end of the aft trim wiring harness comes with the molex mini plug already on it (female, I think). They didn't let us off scott-free though... You still have to connect the wires from the Ray Allen servo to the mini-pins and male plug.
 
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I finally soldered and heat shrink-ed all connections. After making sure all operation was correct.
 
RV-12 wiring

Those pins are problematic because of their size. I think I'm going to use, at the trim servo, a D Sub, male and female, connector and solder the wires into the connectors. Two screws will hold the connectors together and I'll have to enlarge slightly the holes in the mounting bracket. Anybody see a concern about this?
 
I have used D subs in many places for wiring and they work quite well (be sure to limit current to 3A per pin). I would suggest that you not use the solder type which is very difficult to fabricate and will lead to failures in the joints.

A better solution is to used the machined pins and an appropriate crimper (SteinAir has a good one at a reasonable price). The gold plated machined (Milspec) pins are about 30 cents each in quantity but are very reliable and easy to use. The connector bodies are very inexpensive...I buy them at the computer supply outlet Altex in Austin.

Also D subs can be easily connected by using nuts specific for this between the connectors (small 4-40 1/4" tall nuts). And if space is tight, you can forego the shell covers.

In the specific case of the trim wires (26 ga), I have had good success with using the male and female pins directly plugged together without the connector bodies. The normal crimp pins are not sized for the small servo wire, so you have to double the wire in the pin. Use shrink tubing to insulate and hold the pins together and if you have to disconnect later, just cut the shrink off...

And as normal, all wires need to be bundled and tied with tywraps or lacing cord to eliminate any vibration.
 
Crimper that works

I purchased a Tool Aid crimping kit and am very pleased with the results. I bought the kit which has various quick change interchangeable dies for all sorts of connectors. HOWEVER, the kit did not have the die for the small.062 Molex pins so I ordered the 18937 dies for that size connector directly from Tool Aid.

The 18937 die has two crimping dies I used the smaller of the two on the .062 molex pins and had great results. I the kit was around $79, but the crimping tool can be purchased separately for much less. I think 18937 die was under $25.

I have photos on the blog that show the crimping tool here:

http://www.dogaviation.com/2013/01/happy-new-years.html


http://www.dogaviation.com/2013/02/crimping-wiring-connectors-progress.html

Happy Building,
John
 
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