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Are we crimping faston connectors wrong?

rv8ch

Well Known Member
Patron
Had a faston come loose on one of my CHT probes giving slightly wonky readings. Gave all the others a good tug and two more came loose easily.

Went to look for the Steinair video on crimping fastons to make sure I was doing it right, and ran across this video:

https://www.youtube.com/watch?v=nEjbFngw6DY


They say that crimping a faston to a multi-strand wire like we use requires a ferrule. Ferrule from the video:

Ferrule Crimp.png

I added a ferrule and it did feel very solid. Have I done all my other faston connections wrong? Or is this video too pedantic?
 
There are force pull out specs for each size wire. As long as the force is met then the crimp is assumed to be compressed enough for good conductivity and longevity. This video is odd to be referenced by SteinAir as typically it was Stein doing the vids and they were just for aircraft builders like us. This was more generic and referenced a solid core as being common, which it is not for aircraft use. Strain relief, or stiffening of the transition from the connector to the insulated wire is required for tolerance of vibration to prevent fatigue failure of the wire. This is what a faston ferrule does, and can be effected (or improved) by shrink wrap of the end of a connector.

Mostly I was trained to just jerk each connection after crimping to ensure it is tight, adding shrink wrap after the check.

Faston crimpers are not all the same, but the tools I got from Stein were always tested in house and correct. My HF tool has both sides of the compression bars the same, my Stein tool has different bars for the ferrule and wire crimp. This makes the connector insertion single directional for aircraft use. The HF tool was not used for aircraft.

While this may be considered pedantic, they are the details that provide understanding of what is expected by the industry for reliable service. That is what specifications are for, right? If they were not important, then they would not be stated. OK, there are few extremes . . .:D:rolleyes:
 
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... This video is odd to be referenced by SteinAir as typically it was Stein doing the vids and they were just for aircraft builders like us. This was more generic and referenced a solid core as being common, which it is not for aircraft use. Strain relief, or stiffening of the transition from the connector to the insulated wire is required for tolerance of vibration to prevent fatigue failure of the wire. This is what a faston ferrule does, and can be effected (or improved) by shrink wrap of the end of a connector.

Mostly I was trained to just jerk each connection after crimping to ensure it is tight, adding shrink wrap after the check.

Faston crimpers are not all the same, but the tools I got from Stein were always tested in house and correct. My HF tool has both sides of the compression bars the same, my Stein tool has different bars for the ferrule and wire crimp. This makes the connector insertion single directional for aircraft use. The HF tool was not used for aircraft.

While this may be considered pedantic, they are the details that provide understanding of what is expected by the industry for reliable service. That is what specifications are for, right? If they were not important, then they would not be stated. OK, there are few extremes . . .:D:rolleyes:
To clarify, Stein didn't reference this video - I was looking for Stein's video and this one came up in my google search, and I was surprised that they recommended a ferrule.

Stein's video does it the "standard" way.

I wanted to see if anyone else has seen this recommendation, which does seem reasonable, but perhaps unnecessary for most cases. I did find the wires from the EGT/CHT probes to be very fine, and it seems like a ferrule will help the faston hold better. I originally did the crimps using red fastons and the crimper I got from Stein directly on this fine wire, and it came loose on 3 of 8 connections on the right side - I didn't check the left yet.
 
This is what I used in the airlines and the same thing I use now: (AMP red/blu)
Never had a terminal come off. Can be used on all PIDG and Faston red/blu terminals.
Never used a "ferule".
PS: I only use 20ga stranded for cht/egt wires (22 solid is the worst).

product-details.png


https://www.te.com/usa-en/product-59250.html?te_bu=Cor&te_type=srch&te_campaign=ggl_usa_cor-ggl-usa-srch-smbmktg-fy22-googlefeed_sma_sma-2210_2&elqCampaignId=115724&mkwid=29ZcnNWL%7Cpcrid%7C412839223598%7Cpkw%7C%7Cpmt%7C%7Cpdv%7Cc%7Cslid%7C%7Cproductid%7C59250%7Cpgrid%7C97606233784%7Cptaid%7Cpla-891405235439%7C&utm_content=29ZcnNWL%7Cpcrid%7C412839223598%7Cpkw%7C%7Cpmt%7C%7Cpdv%7Cc%7Cslid%7C%7Cproductid%7C59250%7Cpgrid%7C97606233784%7Cptaid%7Cpla-891405235439&gclid=EAIaIQobChMI2qyh5KKp8wIVP21vBB1zvw7NEAYYASABEgJ8o_D_BwE
 
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The video doesnt make it too clear, but you would not use the ferrule and the faston together! They are different crimps for different applications, and both are suitable for stranded wire.

The ferrule would typically be used in industrial applications where the wire was then going to be clamped in a terminal block.
 
The video doesnt make it too clear, but you would not use the ferrule and the faston together! They are different crimps for different applications, and both are suitable for stranded wire.

The ferrule would typically be used in industrial applications where the wire was then going to be clamped in a terminal block.
Right, I see what you mean. Since I thought the topic of the video was faston connectors, I thought he was saying for multistrand wire, you need the ferrule even for the faston. This seems incorrect upon my 3rd viewing.

Looks like I need to plunk down $1700 for a tool that will consistently crimp. Quite surprised these came loose - I thought the whole point was to ensure that a high quality crimp is done as long as you use the right connector for the wire size, the right die, the right tool, and squeeze until it stops. I can't recall if I put these on or if they came from the supplier already on - I believe I did it, and they looked ok, but came loose anyway. Probably should have doubled up the wire.

Thanks for the feedback!
 
I'm using the AMP 59824-1 crimper, it's about $400 new, but you can find it used on Ebay much cheaper. It makes a perfect crimp on the AMP terminals.
 
Looks like I need to plunk down $1700 for a tool that will consistently crimp.

Check the big auction site. Used runs around $200. Search for variations using terms from, “AMP Tyco 59250 red/blue Pidg thead t-head crimper”. Used tool resellers often don’t know the correct terminology. This tool was recommended by Bob Nuckolls in the AeroElectric Connection book. Like Walt, I’ve never had a wire pull free when using it.

A crimp I made yesterday with my AMP 59250 crimper to fix one that came loose that someone else did.
A80B7A2B-D584-4ECB-B02C-05BDFADED99C.jpg

And the offending crimp. Obvious how much better the right tool works.
0F037DE9-B6D1-4ACB-BD1F-7BEC8D374030.jpg
 
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Just me

I never liked crimping terminals that have an insulating sleeve. (FASTON Terminals)

I have found them to be unreliable. I have not used them and instead use un-insulated terminals crimped with a crescent moon crimper and then shrink sleeve over them to reinforce the wire to terminal transition. In addition a second shrink sleeve is put over the metal part that slides onto the mating terminal because I hate having exposed conductors.
 

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Wow - $1700 for a simple crimp tool.

I used the nice Stein crimpers (terminal head and BNC connector head) for over six panel builds and never had a connection fail. I do not however use the cheap auto parts store terminal.

I do suggest that for those little CHT and EGT prob wire you add a #20 or so wire in the crimp. Just a short piece, crimp then cut off the excess.

Reminder, do not crimp over wire insulation. The wire end should be just long enough to fit into the metal part of the terminal.

Carl
 
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Wow - $1700 for a simple crimp tool.

Carl

Well, AMP is very proud of them for sure, but they are far from "simple". When you use one, you'll understand. Sort of like a fine S&W wheel-gun action.

Like the AFM8, they are a joy to use.

Keep an eye out for a good condition used set.
 
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For those tiny wires, can’t you strip it 3 x longer than you need then fold the wire over on itself twice to make the wire being crimped 3 x thicker?
 
The tool that Walt recommends is the do it all tool and it is the most expensive. It is also probably the simplest way to get quality crimps. They can be found on Ebay for much less than the retail price and they will cover most of the smaller crimps that we need to do our our planes.

There are also other AMP (now TE) equivalent crimpers, but you need more of them since they are limited in the size of the crimps that you can do. If you do some digging you can find an AMP/TE spec sheet for the various size of PIDG crimps and the associated crimpers. These crimpers can be found for much less on Ebay, maybe $50 to $75/ea. This is the path that I took. I now have a few of these crimpers for different sizes of crimps/wires.
 
Well, AMP is very proud of them for sure, but they are far from "simple". When you use one, you'll understand. Sort of like a fine S&W wheel-gun action.

Like the AFM8, they are a joy to use.

Keep an eye out for a good condition used set.

I bought mine at Boeing Surplus some years ago. I occasionally see them on Ebay. And, I think Stein has an alternative tool that's considerably cheaper.

Be careful of some of the cheaper FastOn style terminals found in autoparts stores. The insulation will crack and fall off. And, I don't think they crimp as nice either.


--------Added-----------

Not quite as nice to use as the $1,700 one. But, will give the same quality crimp for a whole lot less. Die/Frame:

https://www.steinair.com/product/insulated-terminal-die-only/
https://www.steinair.com/product/ratcheting-crimper-frame-only/
 
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I bought a set of Rennsteig German crimpers. I ran into them at the AEA Garmin training and Rennsteig is good stuff. Not necessarily better than AMP (which I also have and use for coax connectors). Just nice German quality.
613FT1eVbGL._AC_SL1500_.jpg
 
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