How do you open up an AMP 24 pin CPC socket - Page 1
Forum section: electronics / beginners

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 16, 2021, 09:20:57 pm
content: I seem to have a connectivity problem with one of the wiresbut not sure how to open up the connector. I tried poking twoallen keys in the holes which were not occupied and holdingthem with pliers while I unscrewed the back part clock-wise,but it doesn't budge (at least my conclusion from youtubewas that the back part was screwed on) - would appreciate help.

author: CaptDon
author_rank: Super Contributor
timestamp: November 17, 2021, 01:34:42 am
content: That one has a cable clamp and backshell. Take the two screws out of the cable clamp, pull the wedge out. The backshell unscrews in a normal fashion, lefty loosey - righty tighty. You may have to partially insert that connector into its mate to hold it while you unscrew the backshell.

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 17, 2021, 03:40:48 pm
content: Thanks for replying confirming (silly me for not using the other end of connector to hold the connector half)-it did take a bit of force to free the backshell. Looks like one wire doesn't have continuityat connector end - the other end is soldered to a pcb. On the pcb end there are two pcb pushbuttonswitches and no other associated electronics (used for left/right hand) and one doesn't work because of this wire.I'd like to remove the wire and pin to see if I'm lucky and the problem is there - is there a cheap solutionas far as tools are concerned for removing a pin from female connector half and crimping a new pin ?

author: CaptDon
author_rank: Super Contributor
timestamp: November 17, 2021, 09:42:36 pm
content: You really should get up on Ebay Etc. and get the proper AMP pin pusher. You release these pins from the front of the connector and out the back. The pin pusher is a hollow metal tube, Slightly smaller than the hole in the connector and very slightly larger than the body of the pin. As you slide the metal tube into the connector it will compress two or three little tabs that stick out from the pin and face backwards. Once the metal sleeve is pushed in as far as it will go then there is a plunger which pushes down through the hollow tube and pushes the pin out the back side of the connector. You may find some kind of metallic tube that will work for you. We actually had those pin pushers in a vending machine out on the wire floor at GE locomotive factory. All you needed was your employee badge to 'buy' one.

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 18, 2021, 06:42:46 pm
content: Took a photograph of what was written on the shell :"18307 3-1" and separately "AMP 2" :https://www.kynix.com/Detail/348018/183073-1.htmlhttps://www.kynix.com/uploadfiles/pdf/183073-1.pdfThe pdf file indicates the connector is Series 1 , 24 position, shell size 23and uses size 16 contacts. From page 10 table in:https://www.mouser.com/pdfdocs/CPC-Catalog.pdflooks like CPC series 1 can accept contacts type II, III+, posted III+My wire including insulation has a diameter of 1,5mmThe shield including insulation/heat shrink has a diameter of 2,0mm(in case the problem is not in the end and I need to change the cable)Found the cheapest pin/socket remover:https://www.onlinecomponents.com/en/te-connectivity-amp-brand/305183-10355949.htmlthis is a newer version for Type II, III and above contacts.As far as I understand this would be a cheap version of the correct crimper for closedbarrel (I understand closed barrel not having the "ears" at end of pin/socket which need to be bent)for 20-26AWG:https://www.amazon.com/ABN-Deutsch-Closed-Barrel-Crimper-Ratcheting/dp/B01N3KVX8D/ref=sr_1_cc_2?s=aps&ie=UTF8&qid=1521049848&sr=1-2-catcorr&keywords=closed+barrel+crimperWould appreciate a pointer on socket choice and whether the crimp tool iscorrect. One other thought - if the fault is at the socket end, the cheapestwould be to replace present socket with a solder type - would this bea good idea/is there one available ?

author: CaptDon
author_rank: Super Contributor
timestamp: November 18, 2021, 08:21:28 pm
content: The crimper is wrong for sure. It is listed as being for use on D-Sub pins. Those pins are about 1/2 the diameter of your pins. Also, the pin pusher looks correct, however, again, there are two sizes of the pin pushers, the 'big' size that you need, and the smaller D-Sub pin size. Both pin pushers look the same, only their diameters are different. I am going to try to upload a picture in a few minutes of the alternative pin pushers I have.

author: CaptDon
author_rank: Super Contributor
timestamp: November 18, 2021, 08:34:51 pm
content: Here is my alternatives for many connectors. As you can see I have many sizes. They go together as sets Extractor/Inserter. The size that seems to work for the larger AMP pins is from Aiconics (possibly Alconics) part number M81969 / 14-03 that is the blue part, and its mate the white part has the same number on it since they are a set with the little bridge part to hold them together. I can't find my nice metallic AMP extractor, I had one here at the house but it has gone awal at the moment!

author: jpanhalt
author_rank: Super Contributor
timestamp: November 18, 2021, 08:38:44 pm
content: Here's what I use:https://www.amazon.com/YCS-Basics-Pin-Insertion-Extraction/dp/B078NWY1JX/ref=sr_1_15?gclid=EAIaIQobChMI2NrqkOGi9AIVTnZvBB3knQE0EAAYASAAEgLL5vD_BwE&hvadid=174224212721&hvdev=c&hvlocphy=9015391&hvnetw=g&hvqmt=e&hvrand=1208467573440529364&hvtargid=kwd-32810608155&hydadcr=8457_9619021&keywords=amp+pin+removal+tool&qid=1637267614&qsid=142-9500830-7099116&sr=8-15&sres=B006962LBU%2CB00OQPLR4S%2CB07ZC1V2W6%2CB003TYKDWE%2CB082FDGVD9%2CB07GTQJB3H%2CB08LQG4YHN%2CB08ZSXG1RJ%2CB08295ZWL2%2CB0195V3EHK%2CB078NWY1JX%2CB08HSYPJ2X%2CB07476C1LD%2CB0002JMYKS%2CB0922GF9W8%2CB097JS5M6Q%2CB08XWD944Q%2CB08LFZ36XM%2CB08PBQLQ4C%2CB00B88EXCOUnfortunately, the geniuses at Amazon have disabled the ability to snip the image. That price of $16 for 3 is outrageous. They used to give them away.

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 19, 2021, 07:41:30 pm
content: I had no idea this was going to be so much troubleat least I knowit is a CPC Series 1 connector ANDaccording to CaptDon, the crimper I listed was wrong as it was for D-subpins, so I presume the extractor mentioned by jpanhalt is not the correct one.So, I have the extraction tool sorted out - I can find the Aiconics tool on ebayor the AMP tool :https://www.alliedelec.com/product/te-connectivity/305183/70089873/which is actually:https://costarhd.zendesk.com/hc/en-us/articles/1500009288242-Recommended-Tool-for-AMP-Connector-Extraction.I still need to identify which pins/sockets I need to buy anda reasonably priced crimp tool (this may be a one off job).For the pins/sockets, I am looking at p.19 of:https://www.mouser.com/pdfdocs/CPC-Catalog.pdfI am not sure whether "ins.dia. range" means insulation diameter rangei.e. diameter of wire + outside insulationas the wire I am using has an outside diameter including insulation of1,5mm and 2mm for the heatshrinked shielding.If I am interpreting this correctly, I would need pins/sockets ".040-.0801 [1.02-2.03] " for the 1.5mm diameterwire and the same or larger ".060-.1205 [1.52-3.05]" for the 2mm shielding.Can you please help me identify the correct pin/sockets and crimper.If a solder joint socket is available and good to use, this would bethe cheapest as I would not need the crimper.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 19, 2021, 08:05:24 pm
content: I use a lot of homemade tools. When I was working with some avionics connectors, I made the attached tool. As mentioned below, you want something that just goes over pin you want to remove and fits in the hole of the connector. I polished the end so it slipped in easily. McMaster carries a nice assortment of SS tubing that might work. It's where I got mine:https://www.mcmaster.com/miniature-stainless-steel-tubingEdit: Just noticed your country flag. McMaster is probably out of the question for you. At least you can get an idea of the sizes available. It might be easier to buy "hypodermic" tubing, which often/usually goes by gauge size.

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 20, 2021, 07:50:19 am
content: The extraction tool is now clear and I can order it. What I am still not clear onis indicated in post #8.

author: CaptDon
author_rank: Super Contributor
timestamp: November 20, 2021, 02:06:04 pm
content: Years ago I had a large stock of various AMP pins and connectors given to me for my ham radio shack usage. I had no crimper or inserter/extractor so I made the extractor from brass tubing I had that came from the R.C. model airplane hobby and for the crimping I cut away a tiny portion of the 'ears' and simply soldered the wire to the pin. I have seen some industrial factory screwups where they crimped onto the insulation only and the wire had intermittent connection!! I can say none of my soldered pins ever went intermittent!! Be thankful you are not dealing with Souriau connectors, their crimper/inserter/extractor kit cost $3000 U.S.D.!!! We thought one of our kits got stolen but fortunately a field service guy borrowed it for a few days and then returned it!!

author: vjekobalas
author_rank: Regular Contributor
timestamp: November 20, 2021, 08:16:18 pm
content: OK guys, I get the drift - diy is the way to go for a cheap solutionand since it is most probably a one off job, will certainly go in thatdirection.Can you just help me out in identifying correct sockets to buy ?As I said, the wire is 1.5mm diameter including insulationand the shielding is 2mm diameter with heat-shrink -which wire (AWG)is that ?here p.3:https://www.te.com/commerce/DocumentDelivery/DDEController?Action=showdoc&DocId=Data+Sheet%7F1-1773908-9_CPC_Selection_Guide%7F2012%7Fpdf%7FEnglish%7FENG_DS_1-1773908-9_CPC_Selection_Guide_2012.pdf%7FCAT-AM71-C83998Jit says Type II contacts for 28-14 AWGType III 30-14 AWGand where do you buy them (or do they also cost an enormous amount)?

author: vjekobalas
author_rank: Regular Contributor
timestamp: December 31, 2021, 01:03:04 pm
content: In the end I found a source of plastic insert/extractor tools on ebay and afteran enormous amount of time, the packet arrived and I thought it would bea piece of cake BUT unfortunately that is not the case.I would appreciate any ideas/words of wisdom how to remove thepin(socket). As can be seen on the attached photo, I put the yellow wireinto the opening of the white extractor part, slide the extractor fully overthe wire, slowly push the extractor down into the connector andafter centering the wire with a pen cap, the extractor tip opens up a bit moreand slides to the bottom of the pin(socket) - you can see the end of theextractor has been widened a bit to fit over the pin. I try simultaneouslyto push down with extractor and slightly pull the wire then pull extractoralso but always I hear a slight click and feel a ridge and the wiredoes not budge - no matter in which direction I turn the extractor, the resultis the same. Is there a way to remove the pin (asks a very annoyed and disturbed person) ?

author: jpanhalt
author_rank: Super Contributor
timestamp: December 31, 2021, 01:20:19 pm
content: Are you sure the extractor should insert from the back (wire side)? Note the barbs (attached) will be easier to compress if you insert the tool from the front.

author: CaptDon
author_rank: Super Contributor
timestamp: December 31, 2021, 08:08:56 pm
content: The tool absolutely inserts from the front of the connector and the pin can be pushed out through the backside!!!! I specifically mentioned that in an earlier post. Using the blue tool from the front will also require some sort of stiff wire slid down through the hollow blue shank to push the pin out.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 31, 2021, 10:19:16 pm
content: I think someone else mentioned this too. Push the wire toward the front to release the barbs from where they are "dug in."

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 03, 2022, 05:59:04 pm
content: Folks, sorry for not re-reading the posts - after the long period to get the two M81969 / 14-03 extract/inserttools, I had looked at some videos on youtube and the guy was pushing the white extract part of the tool from theback.Anyway, forgetting youtube and getting back to what you have written.I found some 1,5mm2 copper wire as well as some other thinner copper wire (found some steel wire also)for pushing purposes. I took the wire from the back with left hand, pushed it forward into the connector to relievethe barbs and inserted the blue part of the tool (which is weird for me since it says "INSERT" on it)from the front with the right hand.BUT I'm stuck at the insertion of the blue "INSERT" tool from the front - the pin/socket has some wobble/space around itbut the blue tool doesn't seem to go over the pin/socket and down over the barbs.Once I get the pin/socket out, since this is a one-off job, was thinking of just cutting the pin/socketand soldering the wire back since I don't have a crimper - what did you use to cut the pin/socket ?

author: jpanhalt
author_rank: Super Contributor
timestamp: January 03, 2022, 06:10:46 pm
content: The clearances are very tight. All of my tools are quite thin metal (a few thousanths). I was suspicious plastic would work. It sounds like your technique is correct. Maybe just the wrong tool.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 03, 2022, 07:55:37 pm
content: I'm afraid you could be right unless CaptDon can pull me out of this as he has usedthe Aiconics M81969 / 14-03 blue/white tool. I can understand the prices of these toolsfor someone working in the industry every day, but for me it's a one-off and am ina specially delicate financial situation right now, so I can't afford the expensive tools.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 03, 2022, 08:32:49 pm
content: Do you have access to "shim" stock? It is generally mild steel/brass of closely held thicknesses from 0.0005" up to 0.020" and more. I would try steel in about 0.001" to 0.003" (0.05 to 0.1mm), roll it around a piece of music wire the diameter of a pin or slightly smaller, and see if you can get it inserted from the front. Stainless is probably too springy. Any good machine shop probably has some scrap lying around. Most common hobby tubing (like telescoping brass) will have a wall thickness of 0.014", which is probably too thick, but very thin wall SS is also available. McMaster-Carr.com lists a variety of thin wall stainless ("hypodermic") tubing. Some of the larger diameters are available with wall thickness of 0.005".

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 04, 2022, 03:52:47 pm
content: Haven't checked for shim stock yet. Today I have some bad news and worse news for myself -the wire in question broke at the pin/socket and I don't get any continuity. What's funnyis that with an old Fluke 8020A, I do get some low resistance sometimes from thebroken wire to the shielding of the cable on the other end of the cable so it seemsI must replace the cable as it could be creating other problems.Now comes a bigger headache - I need to remove 8 pins/sockets and buy 8 pins/socketswhich can be soldered or modified for soldering as I don't have a crimp tool.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 04, 2022, 03:57:03 pm
content: If you are sure of the connector, it might be easier just to buy a new connector part. For me, I would still give extraction a try, as it will be useful experience.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 04, 2022, 04:39:38 pm
content: I should have said I need to remove 8 sockets rather than pins/sockets.I asked TE connectivity regarding the sockets and they said the following(catalog:https://www.mouser.com/pdfdocs/CPC-Catalog.pdfP22 attached since catalog is too large):"I have checked with our Engineering team and they have mentioned that youcan use Any solder type socket contacts found on page 22 of the attached catalogor crimp style socket contacts on page 19 can be used with this connector. Pagesshould be considered of the document (out of 87).You can select the terminals according to the wire size you use."So, I think I have two alternatives (just due to cost and availability) regarding thesockets(a)extract old sockets and cut them a little and reuse for soldering (haven't hadany experience with cutting/not sure what is best tool for this)(b)from p22 of catalog the cheaper tin solder socket "202237-5"and the tool as mentioned on P22 is "Extraction Tool Part No. 305183" - I presumethis is both for insertion and extraction.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 04, 2022, 06:00:56 pm
content: I don't think that extraction tool can be used for insertion as there is no slot for the wire. The set of plastic tools you have may work or almost anything that can push on the contact and not the wire will work. You might even get by using the wire, but hold it very close to the contact. It is not nearly as critical dimension wise as extraction.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 05, 2022, 10:02:12 am
content: Much appreciated for all the help !!!- I'll report back as soon as I have progress.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 26, 2022, 09:18:36 pm
content: There are 5 cables (2 pieces RG174, 2 pieces Alpha Wire H1 P/N 2461C and 1 piece 4x2x0,25mm LIYCY)and a polyurethane hose in the metal reinforced plastic shroud part of which are connected to the CPC connector.The outer insulation and shield of the LIYCY cable has been worn out due to movement where the cable meetsthe ultrasound head and all cables seem to have suffered heat damage to a certain extent, so in orderto avoid pulling everything apart again in the near future, I've decided to replace all cables.What is the best compound which is smeared on the cables to more easily pull them throughthe reinforced plastic shroud ?Any good ideas on how to better protect the cables inside the reinforced plastic shroudespecially where they enter the ultrasound head - would heatshrink helpor do better cables exist which would handle the motion and heat better ?Here are the cable specs:https://www.specialcavibaldassari.it/sites/default/files/SB_SCHEDA_LiYCY-TP.pdfhttps://www.alphawire.com/Products/cable/alpha-essentials/communication-and-control-cable/2461Chttps://www.prospectasrl.it/wp-content/uploads/2014/06/Catalogue_RG_EN3.pdf(I043 page 7 (19))

author: jpanhalt
author_rank: Super Contributor
timestamp: January 26, 2022, 09:35:26 pm
content: Quote from: vjekobalas on January 26, 2022, 09:18:36 pm1) A tiny bit of liquid detergent in water;2) Spit/phlegmBoth work, the former is more socially acceptable..

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 27, 2022, 03:15:30 pm
content: I can only say that your answer is very ecologicalbut the reason I ask for some type of grease is thatthere are signs of it on the original cables and sincethere was a break in one of the cables (another thread) , I'm thinkingthe "grease" could be playing two roles , to ease pulling thecables through and then to reduce wear on the cables.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 27, 2022, 05:20:40 pm
content: There are special "soaps" for pulling wires through conduits. They are cheap, and the ones I have seen were a light yellow. They are safe with most insulations and are water soluble. They also tend to dry out. The fact you found grease suggests to me it is not they type.A real (petroleum) grease would need to be safe for the insulations. That could be a problem. I do have some special greases (silicone and fluorocarbon based) that are specially made to be safe with plastics and rubber. The silicon version ("Chemplex 710", Century Lubricants Co.) is sold as a water barrier and lubricant for rubber O-rings, etc. It is quite thick. Silicone vacuum grease would be very similar if not identical.The other grease I have is a fluorocarbon ("Krytox GPL206," DuPont,https://www.chempoint.com/products/chemours/krytox-greases/krytox-greases-for-general-purpose-applications/krytox-gpl206-grease?_bt=397943331819&_bk=krytox%20gpl206&_bm=p&_bn=g&_bg=81130520301&gclid=EAIaIQobChMItofc3LXS9QIVL8mUCR3EHQNXEAAYASAAEgI21fD_BwE). It is a true lubricant for gears and such. I use it for the hard plastic gears in model servos.First, I would check whether that grease you see is soluble in water. I suspect it is not. Then check with the connector manufacturer to see whether a grease (e.g., part of waterproofing) is available. If not, and you just want a one-time lubricant and moisture barrier, I would go with a plastic-safe silicone grease (assuming it mixes with the grease that is already there). They are cheaper than fluorocarbons. If you want a lubricating function like for gears, I would go with the Krytox type.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 28, 2022, 06:58:04 pm
content: OK, I must be going crazy, would have sworn there was more of the stuffon the wires and it was more greasy - went back to have another lookand took a photo. I don't understand, was it maybe the oil from thesuctioning, but now there is only a light film on maybe the first meterlength of the total 3m a it's not "powdery" like baby powder but morelike a little flaky like soap when I scrub it with the finger but there's solittle of it(or maybe a bit has beenrubbed off on the cardboard I have on the table due to the oil on the cable)weird

author: jpanhalt
author_rank: Super Contributor
timestamp: January 28, 2022, 07:05:46 pm
content: That looks like a dry lubricant. It could be anything, including talc. I've seen it often inside cables. Is it soluble in water?I forgot to add yesterday, if you need just a little silicone grease, get a little packet of caliber brake lubricant. They are sold in little condiment size tear open packages.

author: vjekobalas
author_rank: Regular Contributor
timestamp: January 29, 2022, 10:45:31 am
content: OK, thanks for all the input - I must have confused the oil/gunk from thesuctioning and use which had gotten over the wires with what is usedfor pulling the cable - maybe I should just try some talc/baby powder and see how it goeswith the old wires.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 03, 2022, 11:38:02 pm
content: Quote from: CaptDon on November 20, 2021, 02:06:04 pmI would appreciate a bit more help - as I didn't want to invest big money into crimping tools, I purchasedthe tin solder tab socket contacts 202237-5(post #4 mouser catalog p22). I also purchased the metalextraction tool Part No. 305183 (which with some fiddling allowed me to extract contacts) and ampurchasing the insertion tool 200893-2 (mentioned on p23 and confirmed by TE connectivity to befor the solder contacts mentioned).What I'm wondering about ahead of time is how I'm going to properly solder the wires to contactsleaving enough room for the insertion tool to slide over the contacts. I haven't tried it yet butobviously I can't have wire doing a U-turn through the tab as it would be in the way of theinsertion tool. Also, what heat-shrink technique is to be used to have best strain relief.For general soldering wire to a tab, I would put heat-shrink which covers the tab and1cm of wire on the wire before the solder joint,tin the tab a bit or apply some flux to ensure proper joint, twist wire strands, poke and bend the wire throughtab (U shape), heat tab, apply solder - but then wire would be protruding and not allow insertion tool to glideup the contact body. Is it enough to apply solder to tab, twist wire strands, tin wire and solder wire just to tab surfaceand have a piece of heat-shrink cover tab + 1cm ?

author: jpanhalt
author_rank: Super Contributor
timestamp: February 03, 2022, 11:46:13 pm
content: Are the pins you have extracted crimped, soldered, or both?Can you post a picture of the replacement pins you have? If it is crimp and solder, I have often crimped manually with fine nose pliers (e.g, hemostat-like tools). If it is crimp only, you will need a crimper. There are general purpose ones that are not expensive and may work.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 04, 2022, 10:58:43 am
content: Attached is a picture of the new solder pin ( post #4 mouser catalogue p22 part 202237-5)on the left and the original one where I cut off one wire - it is only crimped.I'd like advice on procedure of soldering/heat shrink so that the insertion tool will still slide over the pine.g. do I put a puddle of solder on the tab hole, tin stripped and hand twistedstrands, heat puddle and insert wire on surface - I'd appreciate detailed explanationand then I can practice on some junk - this has to be done to my best abilityas my daughter's job is relying on this machinebut willing to do it

author: jpanhalt
author_rank: Super Contributor
timestamp: February 04, 2022, 11:43:06 am
content: Your new pin looks like it is designed for soldering only and not crimping. The old pin (top) is definitely just crimped.I am familiar with soldering to a lug (the tab with a slot) and covering with heat shrink. The heat shrink acts mostly to support the wire and secondarily as insulation. Support of the wire is important, because a soldered connection introduces weakness where the soldered strands of wire meet unsoldered wire.Heat shrink can be had in different thicknesses. It doesn't need to extend very far in to the plastic shell. One might argue that it doesn't need to extend into the shell at all. It only needs to stabilize the wire to lug junction.As for technique. I would just do a good solder joint. Making a puddle won't help.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 04, 2022, 01:48:34 pm
content: Yes that's correct - the new one is solder only (every other type they sold costsan arm and a leg ,needs to be bought in large quantities and requirescrimping tool.Can you describe a bit more the soldering as I'd like to ensure I get that right ?- what length of wire do you strip off insulation/ how much of itis on the tab and how much extends without solder- how do you place the wire (I can't allow solder/wire to go out of boundsof the diameter of the pin as the insertion tool needs to slide over that areai.e. can't bend it through the tab and add as much solder as I would like(that's my initial thought)- your procedure of soldering i.e. each step of what you do (I describedwhat I was thinking of doing but I am far from an expert in soldering)

author: jpanhalt
author_rank: Super Contributor
timestamp: February 04, 2022, 02:40:46 pm
content: OK, here's what I do in similar but not identical situations of soldering to a lug. You may not need or want to do each step.1) First I work in layers. I often have two layers of heat shrink. The first is over each conductor and pin; the second is over all conductors. That is to stabilize the soldered connections as mentioned earlier. Assume you want heat shrink over the soldered joint, but the connectors with heat shrink will not fit the housing.Be sure the conductors are about equal in length. That may not be necessary with long cables, but as the cable gets shorter, a few long wires mixed shorter wires will not lay nicely. Slide closely fitting heat shrink over each wire. Then slide the big heat shrink over all the wires. That's because, you cannot add heat shrink later. Push those heat shrink pieces as far from the soldering area as possible. You don't want the heat from soldering to shrink it.Now, strip the wire. A short strip -- just enough for soldering -- is sufficient. I do that after slipping the heat shrink on to avoid snagging individual strands. If you forget? No big deal, just be careful to get all the strands twisted together. I use a finger tight twist. In old times with point-to-point wiring, instructions usually told you to make a good mechanical joint before soldering. Today, having that much space is a luxury. I then slip the twisted wire through the lug and solder on the far end (image 1, plug). Be sure all of the strands are through the hole. I figure that is not much different than soldering to a THP hole. If there is space (image 2, hook), I will make a better mechanical joint. I don't think you have the space. Worse case, you may not even have space to slip through the hole. In that situation, I would lay the wire over the hole and solder same side (no pictures).2) After all pins have been attached to wires, I assemble the plug. Push the small heat shrink in as far as it will go. (Assuming heat shrink over a pin cannot be inserted in the plastic receptacle.) At this point, you can shrink all of your small heat shrink tubing at once or individually. Then put the big heat shrink over all, heat shrink it.3) Finally, assemble the shroud and cable clamp if there is one. Many times, I shrink everything at once, but that is only when there are a few wires. In your case, you want to be sure heat shrink over each wire is properly shrunk.Hope that helps.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 04, 2022, 08:49:50 pm
content: Thanks, that was very instructive. Your situation is similar but if I see correctlyon the images, you have two holes on the connector with the wire insulated part on the side of themetal "ears", then going out one hole and coming back through the second one,so you have quite a bit of stripped cable /soldering surface area and the metal "ears" to hold thewire/additional strain relief compared to my situation.I checked the attached the instructions for the insertion tool and the maxinsulation diameter of the wire is .09 (that's 2.3mm) whereas mine is a 4x2x0.25mm2wire with measured 1.1mm insulated diameter / 1mm soldered wire so it shouldfit and maybe even with a bend.Looking at the rough attached sketch, could you just clarify somefine details about soldering (I always go a bit overboard to get things right):For soldering with a bend I've seen some instructions where such soldering to tabs(probably on much larger tabs/projects) is done such that the wire is bent U shapedthrough the tab hole i.e. the stripped wire part is soldered from top of tab above hole,through hole and on the other side. For my case I have a tiny tab with just 1mm metalabove tab hole, so I guess a reasonable length of stripped wire being some 4mm - 5mmfor good solder connection + bend would be needed, so the bend would be somewhereat the end of the tab hole and insulated wire part not touching tab. Does this sound OK ?The heat-shrink would go along the wire some distance across the insulation and to the solder joint.Is it additionally practiced to heat-shrink across insulated part of wire and the tabto mimic the metal ears (or maybe use just this heat-shrink and not the one on the wire(if insertion tool allows) ?For soldering without the bend we again use some 4mm-5mm stripped wire for good solder jointand the wire could be moved further down the tab so that theinsulation is in contact with the tab or should it stay like in the top drawing or doesn't it matter?Similar question about heat-shrink along wire and/or across wire/tab (if insertion tool allows) ?

author: jpanhalt
author_rank: Super Contributor
timestamp: February 04, 2022, 08:58:37 pm
content: Does the tab extend out of the housing when it is fully inserted? If so, I wouldn't worry about wire diameter. Just push the heat shrink up to the housing.If the tab is fits in the housing, I don't anticipate any problem in soldering as it is wider than your wire. The only disadvantage is that you won't have heat shrink to support the wire+soldered joint.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 05, 2022, 06:30:45 am
content: Thanks for all the help - I've gone overboard with the questions and detailsas I'm a bit stressed to get this right but don't have the experience to justdo it. Will report back results.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 05, 2022, 07:33:41 am
content: Just curious - how would soldering to new solder contacts compare as far asstrength/longevity etc. to cutting off existing contacts with excess wire andsoldering that wire to new cable instead ?

author: jpanhalt
author_rank: Super Contributor
timestamp: February 05, 2022, 10:03:18 am
content: You seem to be proposing to fix something that is not broken, which is generally not a go way to proceed.Now, what about the tabs?

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 05, 2022, 03:31:40 pm
content: You misunderstood - I need to replace the original cables which have crimpedpins - one of the cables is completely broken about 20cm from the end while allthe cables are out of the conduit, I intend to replace all of them as they are hardenedfrom heat/movement and their cost is much lower than having to put themachine out of service and open everything again in case of failure in thenear future. I purchased the solder tab pins as replacement and know howto proceed with that solution but was asking whether the idea of taking theold cable and snipping off old crimped pins together with a length of wire attached andsoldering that wire to the new cable and including heat-shrink is a worse solutionthan soldering new cable to the new solder tab pins. I was so thinkingin-the-box about replacement that I didn't think about that alternative idea.Not sure what you are referring to by "Now, what about the tabs?"

author: jpanhalt
author_rank: Super Contributor
timestamp: February 05, 2022, 04:49:07 pm
content: Rather than reuse old wire, some of which is heat or age hardened, I would use new, fresh wire of thesame or bettertype for everything. There are occasions when that is not practical, say a 70 year old house, but with a cable or wiring harness that is laying on your bench, I would do it.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 06, 2022, 07:41:10 am
content: OK, I guess I didn't focus my question properly. The side of the cableswhere the connector is i.e.where the pins are, has not been heat/motion hardened(heating and motion is on the other end of 2.5m length of cables), so thecable/wires at the end where the pins are should be OK.The question is - is there any big difference between taking the original cable,snipping off last X cm of each wire together with crimped pin and soldering these wiresto the new cable rather than taking the new cable and soldering solder tab pins to it ?Which of the two solutions is more durable/less problematic ? I ask ahead of timeas it may be easier to insert the crimped pins than the solder tabbed ones and they may bemore secure connections depending on the quality of my soldering.These may be silly questions to someone who has a lot of experience with soldering.

author: JohanH
author_rank: Frequent Contributor
timestamp: February 06, 2022, 10:05:38 am
content: Quote from: vjekobalas on February 06, 2022, 07:41:10 amAs has been told in the thread, solder joints can't stand a lot of wiggling, so would have to be within the strain relief or shell of the connector where the wires will not be bent. So it depends on the physical and mechanical properties of the connector you have. If the cable isn't going to moved around a lot, then it doesn't matter as much. I wouldn't hesitate soldering on the new terminals. Use flux on wire ends (and terminals) and you will get a very good flow of solder and attachment will be good.

author: jpanhalt
author_rank: Super Contributor
timestamp: February 06, 2022, 10:18:33 am
content: Do the simplest and help your daughter keep her job. Consider it a "fix" not a restoration.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 07, 2022, 09:08:49 am
content: Unfortunately I can't continue with the job till all the cables arriveso I'm asking all the questions and need to do some practice with thesoldering - I still have a roll of solder from the Australian company Cap Alloy(probably 60/40)probably from early 1980's at time of my uni days when I lived in Australia- tells you how muchsoldering I've done.Regarding the solder, digging around the web I understand the old soldershould be OK and I'll certainly practice with it to make sure but I have neverused flux - always only the solder which already has flux in it.I understand liquid rosin flux with non-corrosive residues is the oneI should use in case I need it for the wires and pins (and generally for pcbs)- could someoneconfirm this flux which I can find in a local shop is the correct onehttps://termopasty.pl/wp-content/uploads/2019/07/Topnik-LP1_EN.pdf

author: jpanhalt
author_rank: Super Contributor
timestamp: February 07, 2022, 09:59:29 am
content: For ease of hand soldering, I use a flux cored solder, namely Kester 63/37 with #44 RA rosin flux. Diameter can make a difference in ease of use. For most through hole soldering I use 0.031" (~o.8 mm). For SMD, I go to 0.015". Another common size is 0.025" (~0.65 mm). Too large a diameter can lead to excessive solder and heat on the joint. I find it is easier to use a smaller diameter on a larger part than the other way around.For a connection like you are making, cleaning may not be necessary even with full-strength rosin cored solder. (Early no-clean solder simply had reduced rosin.) A eutectic solder tin/lead/silver (62/36/2) will give very nice looking joints and are maybe a little stronger (see a recent thread here).Edit: I can't comment on using a liquid or paste flux with solid wire solder as I have no experience with that in electronics. That is what I use for plumbing, but that is quite different. When I want additional flux in electronics, I use #44 paste flux.

author: JohanH
author_rank: Frequent Contributor
timestamp: February 07, 2022, 11:00:07 am
content: With most types of solder, usually additional flux isn't needed. Rule of thumb: whenever you heat any existing solder or solder joint, without adding fresh solder at the same time, separate flux is needed. Because heated solder doesn't contain flux any more, so becomes sticky and grainy and won't flow or break the oxidation layer. I use gel type flux in a syringe and I've experienced it helps a lot when soldering wires, especially wire to wire. Due to surface area and oxidation, just adding fresh solder to a wire doesn't make it flow easily into the whole wire. But add a small amount of gel type flux first on the wire and the solder flows very fast, penetrating the wire immediately and attaching to any surface you are trying to solder the wire to.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 07, 2022, 11:56:49 am
content: OK, I'll get some flux just in case it's helpful.Jukk - are you using gel type as it doesn't spreadaround like liquid and do you use some sort of brushfor application to wires / non-spot application ?I must admit the variety of flux obtainable locally is a bitlimited - would the one in my previous post or this one:https://www.tme.com/Document/4711caa58b9b001dc51b50cbbdc7f472/ALPHA_RMA7_TB_ENG_W2.pdfpicked out of one of these be OK ?:http://elmatis.hr/SearchResults.aspx?searchText=flux

author: JohanH
author_rank: Frequent Contributor
timestamp: February 07, 2022, 12:21:39 pm
content: Any rosin based flux will do as the no-clean variants. I use the cheapest type of "SMD FLUX GEL". I've used liquid and harder paste types, but I like the gel the most. I just apply it with the syringe. It does make things a little bit messy due to residue, but I always clean PCBs with IPA and a lint-free paper towels and brush. But I think you are overdoing this a little. For a one-off project, you should get by with the solder wire you have.

author: vjekobalas
author_rank: Regular Contributor
timestamp: February 11, 2022, 04:12:33 pm
content: OK, all the cables have arrived and I'm about to pull the cables through the conduit andstart cutting/soldering but still have one more issue: one wire on each of two cables ,going to eachof the ultrasound transducers, have small 100ohm 1% resistors (length about 3.5mm / diameter 1.4mm)soldered to them.After de-soldering from transducers on the attached photos you can see red lines showing directionin which wires were attached and pointing to bits of outer paint of resistors stuck in what looks like hot glueI am guessing resistors were soldered to wires and then hot-glued in place for soldering to ultrasoundtransducers as well as to hold the resistors during operation. The resistors still measure 100 ohm and was thinking of reusingthem but also looked at replacements and saw that those size resistors came inpower ratings up to 0.4W (have no idea which power rating they are) - 0,4W is the highest rating I found in that approx size:https://hr.mouser.com/ProductDetail/Vishay-Beyschlag/MBB02070C1000FCT00?qs=Jr4%2Ft4s12JXp%252BbxcGzwGMQ%3D%3DJust curious other than the size/ease of positioning the small resistors, is there any reason I couldn't use a 0,6W metal film 6,5mm/2,2mmresistor for this application (instructions indicate ultrasound frequency is 1MHz / sinusoidal modulation 20 - 60 kHz)- the wire with the resistor and a coax are attached to each transducer.I have 0,6W metal film resistors lying around the only problem may be that they are about 30 years old) :(have I think 0,5W carbon film also 30 years old - yes much bulkier than the small ones) ?

author: jpanhalt
author_rank: Super Contributor
timestamp: February 11, 2022, 04:46:19 pm
content: I don't think increasing the wattage rating of the resistors will make a difference. Certainly not with with the small change you are making.It's too late now, but the trick to releasing hot melt or removing gobs of it is just to apply a small amount of isopropyl alcohol and allow that to wick under the hot melt. It then releases very easily. I use 91% or higher concentration, because that is what I have. I don't think the concentration is critical. It does not seem to dissolve much if any of the hot melt. It just releases the adhesion. Of course, don't get it on any hot melt you don't want to remove.I would probably reuse the resistors unless they are obviously damaged.

author: vjekobalas
author_rank: Regular Contributor
timestamp: April 05, 2022, 06:36:30 am
content: Better late than never - I'd just like to thank everyone for the input - the project was a success-my daughter said that the machine never worked so well. I am guessing that the cablethat was almost completely broken when I opened it up was in a bad shape from the very beginning.So, what did I do - I changed all the cables, swapped out the old resistors for 0,4W ones i.e. ones withhighest wattage I could find for resistors of same size as the original ones as I had no idea of wattage,and used solder contacts to avoid costs for a crimper.My takeaway from this "project"(a)If you don't have a service manual, take a lot of photographs and maketables of wiring connections and anything that may get you into trouble ifyou don't note it.(b)If you use solder contacts instead of crimped ones be sure the socket is deep enoughas solder contacts protrude further into the socket/ are longer.(c)Initially I got my hands on some plastic tools for removing contacts - they did not work at all- I would not recommend them -get yourself metal tools and for my casethe original AMP one. If you are using solder contacts, you don't need the contact removaltool because the contacts protrude so much from the socket that you just push them in with your fingers.The AMP insertion tool funnily enough costs as much as four removal tools (around $100) whichalthough the extraction tool is more complex. Use a permanent marker to mark extraction tool full depthinsertion mark. Do this by fully inserting tool in a position that is not occupied by a contact. This is done so thatwhen you insert the tool over/around a contact, the tool initially goes to the point where the"ears" of the contact are - at this time, you need to push the tool further to that markand at the same time lightly push the extractor "piston" to pop the contact out.(d)A little baby powder is more than good enough for getting wires through conduit.