Source for unplated copper fork lugs? - Page 1
Forum section: electronics / general

author: TERRA Operative
author_rank: Super Contributor
timestamp: February 02, 2025, 11:14:36 am
content: I'm looking for a source of unplated copper fork lugs that doesn't involve a stupid high price for a minimal amount to make some low-EMF leads.Does anyone know where I can find this sort of thing?

author: Overspeed
author_rank: Frequent Contributor
timestamp: February 02, 2025, 01:27:41 pm
content: HelloI am in process to make some , I will post soonMain problem is not the fork itself but the crimp area as that a key factor to avoid EMF by soldering but also to ensure safe bomb proof crimp.Right now I try 2mm thick copper with a 0.8 mm thickness on the crimp area to allow reasonable wire gage.Could be possible to locate spade fork for Hifi purpose , but that generally for heavy gage wire .RegardsOS

author: aronake
author_rank: Frequent Contributor
timestamp: February 02, 2025, 02:04:02 pm
content: These have been working well for me:https://item.taobao.com/item.htm?id=564815781992I think this version is for slightly thicker cable. The one for smaller cable may be better for your needs, but seems to be sold out.There is also the gold plated version, which i also have used, and generally think is better. At least where i live in pretty high humidity, pure copper get oxidized quite quick. So I am generally moving over to gold plated.https://item.taobao.com/item.htm?id=724586973405This seems to be the thinner cable version.

author: TERRA Operative
author_rank: Super Contributor
timestamp: February 02, 2025, 03:37:01 pm
content: Thanks for the links, I'm not sure how I can buy from Taobao and send overseas? Are they available on Aliexpress?@Overspeed, I'm interested in how you go.

author: Overspeed
author_rank: Frequent Contributor
timestamp: February 02, 2025, 04:19:07 pm
content: Quote from: aronake on February 02, 2025, 02:04:02 pmHellobest practice is to run an electropolishing if that pure copper before crimping , and before electropolishing to remove any burr generated by stamped engraving on the surface , in the aim to insure a near perfect flat surface for a better contact and no micro galling under torqueprice look goodRegardsOS

author: The Soulman
author_rank: Super Contributor
timestamp: February 02, 2025, 04:21:50 pm
content: https://www.ab-precision.de/products/cables-accessories/

author: Kean
author_rank: Unknown
timestamp: February 02, 2025, 06:33:06 pm
content: Quote from: TERRA Operative on February 02, 2025, 03:37:01 pmFor Taobao you can use superbuy.com website to handle the translation, purchase, and reshipping.I've used Superbuy a couple of times with no problems.

author: MiDi
author_rank: Frequent Contributor
timestamp: February 02, 2025, 07:40:56 pm
content: Quote from: aronake on February 02, 2025, 02:04:02 pmDo you know if this is direct gold plated on copper w/o intermediate layer?

author: garrettm
author_rank: Frequent Contributor
timestamp: February 03, 2025, 01:56:36 am
content: Well, the cheap-ass solution is to use citric acid or another weak organic acid to remove the tin plating on normal spade/fork or ring terminals.Weak organic acids act as reducing agents for copper oxides but will react with tin and turn it into a soluble compound that is nontoxic. And is very low effort.Anyways, this is how I get my "copper" terminals.Crimping, on the other hand, is complicated. The "crimping industry" intends for round O type barrels to be crimped by smashing them into an oval--not folding a U into a B like most connectors. That, or indenting the bottom side of the barrel. Both methods are subpar. Connectors that do use the U to B crimp style are generally brass. Pure copper connectors (with tin plating) use the O barrel and generally have insulating plastic covering the barrel. You __can__ bend the O into a U and then manually crimp into a B. This is what I do. And there are some random Chinese crimp tools that allow you to crimp like this with copper spade and ring terminals, but I have not tried using them.

author: garrettm
author_rank: Frequent Contributor
timestamp: February 03, 2025, 02:05:56 am
content: As for gold plating: gold readily diffuses into copper. So a diffusion barrier like nickel is plated on first to prevent the gold from traveling into the copper. What you want is called "gold flash" where a THICK plating of gold is added directly to the copper. This thick "flash" layer has enough gold that the diffusion process doesn't materially affect the surface coating.The primary use of a diffusion barrier is to use _economically_ thin gold plating. But these thinner gold platings DO NOT protect the under coat and as a result, the nickel can still corrode and lead to the gold pealing off or rubbing off from normal wear and tear. I have many, many examples of both in my parts box. The thick gold flash coatings are the "metrology" grade coatings from the 1960s (think L&N binding posts) that we will never see again outside of specialty applications for unconscionable amounts of money.

author: tooki
author_rank: Super Contributor
timestamp: February 03, 2025, 02:12:04 am
content: Quote from: garrettm on February 03, 2025, 02:05:56 amUmmmm… no?“Gold flash” means a verythinlayer of gold, not athickone. So “thick gold flash” is a contradiction in terms.

author: laichh
author_rank: Regular Contributor
timestamp: February 03, 2025, 02:29:58 am
content: For low thermal emf spade lug application, I get a bunch of Panduit P18-14F-M (cheap) & have them re-plated by a local vendor with the following specifications:Method of Plating: Barrel - May cause some minor dent & scratches during barrel rotating plating process.To strip off existing Tin layer by using Tin over copper formulated Tin stripper.Copper Flash As Under Coat / Hard Gold Plate PER MIL-G-45204, Type II, Grade D, Thickness: 0.25μm - Minimum.Cost breakdown:Spade Lug: Panduit P18-14F-M ~$0.33/eachGold plating: ~$2.9/eachThe result is visually identical to LowThermal 2758-fork.https://xdevs.com/doc/LowThermal/2758/2758-series-data.pdf

author: TERRA Operative
author_rank: Super Contributor
timestamp: February 03, 2025, 04:57:55 am
content: Maybe I can do step 2 myself to some plated lugs to get the bare copper... Do you have any details of the tin stripper? I just read garrettm's post. I'll go get some citric acid or vinegar etc and try some experiments.

author: Overspeed
author_rank: Frequent Contributor
timestamp: February 03, 2025, 06:49:05 am
content: Quote from: TERRA Operative on February 03, 2025, 04:57:55 amHelloyou can perhaps try electrolysis with low current to pull out the Tin coatingand after run a electropolishingRegardsOS

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: February 03, 2025, 10:05:31 am
content: Hello TERRA Operative,Quote from: Overspeed on February 03, 2025, 06:49:05 amSure that usingquality copper terminalsand removing thepure tin platingwith medium concentrated Hydrochloric acid (32- 37 % should be sufficient) would be less expensive than procuring the 'metrology grade' versions.

author: Simmed
author_rank: Frequent Contributor
timestamp: February 03, 2025, 07:02:45 pm
content: i think this the same shop rec by zlymex a very very long time ago($rmb) 0.95 a pc, i think they used to be $0.65https://item.taobao.com/item.htm?id=652899496172in the shop, there are other volt nuttery bits and piecesi just realized aronake is showing same link abovebut due to what appears to be selecting "world" or "china" portalthe shop seems to display different items to the "browser"its like a "secret" shop at the rearworld portal shop only has 10 items for salethe first pic is "china portal" per say