VansAirForceForums  
Home > VansAirForceForums

-POSTING RULES
-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.






VAF on Twitter:
@VansAirForceNet


Go Back   VAF Forums > The Never Ending Debate Section > Tools
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

View Poll Results: Which crimp is better?
Crimp A 4 16.00%
Crimp B 8 32.00%
Either is acceptable 9 36.00%
Neither is acceptable 4 16.00%
Voters: 25. You may not vote on this poll

Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 09-07-2022, 09:59 AM
rv12is's Avatar
rv12is rv12is is offline
 
Join Date: Aug 2019
Location: Peachtree City, GA
Posts: 54
Default

Quote:
Originally Posted by BillL View Post
But - the pull test is the real test of a crimp after the visual inspection.
I'm not sure of the proper way to perform a pull test. However just based off of the name, I did perform a couple of tests.

Test #1: I crimped identical pins onto each end of the same 22 AWG wire. One side crimped with tool A, the other tool B. I then grabbed each pin with pliers and pulled until failure. The source of the failure was the wire pulling out of crimp A.

Test #2: I crimped a pin onto a 22 AWG wire. Using vice grips I secured the terminal to the bench vice. I then attached the wire to a fish scale and slowly pulled until failure. Crimp A failed at around 19 lbs, while crimp B failed at 17-18 lbs.

No wires were damaged or broken. They simply pulled out of the crimp. While my sample size is way too small to conclude anything, it appears the crimp retention force (or whatever the proper term would be) would be similar between the two tools.

So now the remaining question from my testing is, what's the proper minimum force for an acceptable crimp connection on a 22 AWG wire?
Reply With Quote
  #12  
Old 09-07-2022, 10:19 AM
rv12is's Avatar
rv12is rv12is is offline
 
Join Date: Aug 2019
Location: Peachtree City, GA
Posts: 54
Default

Quote:
Originally Posted by fl-mike View Post
Send 'em both back and buy a used Daniels AFM8!
I like your thought process. If I was building any RV other than a 12iS that's likely the approach I would take. However, with the 12iS the wiring harness comes mostly assembled. There are probably less than a couple dozen pins that will need to be crimped with this tool.

The SteinAir crimpers were free and the Greenlee crimpers are some that I've had for a while. If either of these produce acceptable crimps, I don't think I can justify the expense of a tool that I would use so few times.
Reply With Quote
  #13  
Old 09-07-2022, 10:36 AM
Mikeyb Mikeyb is offline
 
Join Date: Nov 2018
Location: Pasadena ca
Posts: 207
Default Down the rabbit hole we go

I don’t think you will find any manufacturer of Mil-DTL-24308 type connectors that will list those tools as acceptable. What you are after is a oxygen free connection between the connector and wire. That is dependent on the wire size. Looking at the outside doesn’t show that. It also has to make a crimp that doesn’t distort the connector. You could smash it with a vise and pass a pull test maybe even get it to insert but good luck getting it out. If you want it done right you have to buy an approved adjustable crimper and it’s going to cost 5 times more than you want to spend.
__________________
Mike
N36MB
SN 83764
IO360-M1B
Hartzell Composite CS
Phase 1 complete 10/29/22
KAJO

Last edited by Mikeyb : 09-07-2022 at 11:24 AM. Reason: Add connector distortion
Reply With Quote
  #14  
Old 09-07-2022, 11:10 AM
PilotjohnS PilotjohnS is online now
 
Join Date: Jan 2016
Location: Southwest, USA
Posts: 2,538
Default

Quote:
Originally Posted by rv12is View Post

No wires were damaged or broken. They simply pulled out of the crimp. While my sample size is way too small to conclude anything, it appears the crimp retention force (or whatever the proper term would be) would be similar between the two tools.

So now the remaining question from my testing is, what's the proper minimum force for an acceptable crimp connection on a 22 AWG wire?
The wires should break and not pull out.

Edit: for aircraft use, I think there is a pull spec minimum. I will update my answer to say that for aircraft use, as long as you meet the pull spec, they will be good enough. your plane, your decision.
__________________
John S

WARNING! Information presented in this post is my opinion. All users of info have sole responsibility for determining accuracy or suitability for their use.

Dues paid 2022, worth every penny

RV9A- Status:
98% done, 2% left to go
To Go: wing mounting, engine baffles, wing tips, move to airport
www.pilotjohnsrv9.blogspot.com

Last edited by PilotjohnS : 09-07-2022 at 12:46 PM.
Reply With Quote
  #15  
Old 09-07-2022, 11:31 AM
rv12is's Avatar
rv12is rv12is is offline
 
Join Date: Aug 2019
Location: Peachtree City, GA
Posts: 54
Default

Quote:
Originally Posted by Mikeyb View Post
...Looking at the outside doesn’t show that...
Your comment got me curious. This probably tells me absolutely nothing... but I ground away part of a connector in an attempt to examine the inside.

Click image for larger version

Name:	PXL_20220907_160735801.MP.jpg
Views:	57
Size:	328.1 KB
ID:	30642
Reply With Quote
  #16  
Old 09-07-2022, 11:52 AM
rv12is's Avatar
rv12is rv12is is offline
 
Join Date: Aug 2019
Location: Peachtree City, GA
Posts: 54
Default

Quote:
Originally Posted by PilotjohnS View Post
The wires should break and not pull out.
If this is the case, then neither crimp is acceptable. Maybe I should stop being so cheap and just buy the proper tool...
Reply With Quote
  #17  
Old 09-07-2022, 12:23 PM
rv8ch's Avatar
rv8ch rv8ch is offline
 
Join Date: Feb 2005
Location: LSGY
Posts: 5,021
Default

Quote:
Originally Posted by rv12is View Post
If this is the case, then neither crimp is acceptable. Maybe I should stop being so cheap and just buy the proper tool...
Bob Nuckolls - wiring and aircraft electrical system expert - says you should be able to pull about 8 lbs on an AWG 22 connection - so your crimps were fine.
__________________
Mickey Coggins

http://www.rv8.ch/help-people-in-ukraine/
Reply With Quote
  #18  
Old 09-07-2022, 12:45 PM
Mikeyb Mikeyb is offline
 
Join Date: Nov 2018
Location: Pasadena ca
Posts: 207
Default

Several people noticed Connector B appeared bent. That would be a bust for most aerospace QA inspectors. Just for kicks try putting both in a connector body and then try extracting them.
__________________
Mike
N36MB
SN 83764
IO360-M1B
Hartzell Composite CS
Phase 1 complete 10/29/22
KAJO
Reply With Quote
  #19  
Old 09-07-2022, 01:46 PM
rv12is's Avatar
rv12is rv12is is offline
 
Join Date: Aug 2019
Location: Peachtree City, GA
Posts: 54
Default

Quote:
Originally Posted by Mikeyb View Post
Several people noticed Connector B appeared bent. That would be a bust for most aerospace QA inspectors. Just for kicks try putting both in a connector body and then try extracting them.
There is a very slight bend to connector B. It's easily visible under the microscope, but not apparent without magnification. I did test it in a connector body, and (from what I could tell) there was no change in insertion, locking, or removal.

Just for testing purposes, I did crimp a few more terminals with crimp tool B. All of them exhibited a nearly identical bend.

Even though the bend is slight, and it didn't appear to cause a problem in my one off test, I think this is reason enough to prefer crimp tool A over crimp tool B.
Reply With Quote
  #20  
Old 09-07-2022, 03:09 PM
BillL's Avatar
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
Posts: 6,850
Default Pull Test

Attached is a pull test table. Use the Mil spec chart. The numbers are a minimum for not failing. There are other publications and standards that have the pull test within but IMO not worth having. Your test was good, as was the value. The DMC tool will precisely restrict the deformation of the crimp according to the specific pin and wire dimensions, that is what the tools you have don't do.

FYI, the DMC (Daniels) is the gold standard, and depending on military funding cycles you can find many or none on ebay. Get a pretty one for the best price you can find. Also, there is a maker of a clone, China of course, named JR Ready. Also on eBay. While it is still expensive, I would prefer a used DMC before buying a new clone for $375. The positioners are another matter. They simply hold the pin in the center and axially correct. I got 5 of the popular positioners for 1/2 the price of a new DMC. They were perfect.

Click image for larger version

Name:	Crimp Pull Table.png
Views:	64
Size:	1.43 MB
ID:	30646
__________________
Bill
RV-7
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 11:05 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.