Crimping Confusion

[MSL]

I'm trying to crimp copper terminals/lugs onto 8 gauge copper wire and the wire falls right out. The wire fits into the lug more loosely than I would think it should, and, when crimped, the lug is clearly not fully crimped. I even tried putting a non-insulated ferrule on the wire before inserting it into the lug, and it was better, but I could still pull the wire out.

I'm using this crimper: https://www.amazon.com/dp/B0B312RF9G...sin_title&th=1

and these copper lugs: https://www.amazon.com/dp/B0C96G27YL...sin_title&th=1

I was going to try the next smallest lug, for 10 gauge wire, but the assortment I bought doesn't offer one with a 3/8" hole.

I've double checked and I'm definitely using the correct lugs and crimper inserts.

I assume my problem is poor quality crimper and/or lugs.

Anybody else run into this?

Can anybody recommend a crimper and lugs they've used successfully? Harbor Freight?

Thanks, Mark

[TomW]

I have no electrical credentials. But, it used to be that uninsulated terminals/lugs were crimped on with a tool that pierced the crimp surface for a really strong bond. That same tool could be used on insulated terminals/lugs. Later, the crimping tool was given a "toothless" crimping surface (similar to the tool you bought) to not pierce the insulator. I wonder if the uninsulated lugs you purchased are incompatible with the crimper?

TomW

[MSL]

Originally Posted by TomW

I have no electrical credentials. But, it used to be that uninsulated terminals/lugs were crimped on with a tool that pierced the crimp surface for a really strong bond. That same tool could be used on insulated terminals/lugs. Later, the crimping tool was given a "toothless" crimping surface (similar to the tool you bought) to not pierce the insulator. I wonder if the uninsulated lugs you purchased are incompatible with the crimper?

TomW

Thanks for the reply. I could be wrong, but I'm pretty sure the crimper is intended for non-insulated lugs.

Thanks again, Mark

[richard5933]

I've found that lots of the overseas-produced lugs are not accurate for use with US wire sizes - they're actually designed for use with metric wire sizing and then the chart is a sort of approximation for the US market.

If you don't have a 'next-size-down' that fits the mounting stud, then you might be able to get it to crimp tight enough by using the next smaller size die in the crimping tool.

Or, if there is enough meat left on the lug, drill out the next smaller size to accommodate the 3/8" stud.

[MSL]

Originally Posted by richard5933

I've found that lots of the overseas-produced lugs are not accurate for use with US wire sizes - they're actually designed for use with metric wire sizing and then the chart is a sort of approximation for the US market.

If you don't have a 'next-size-down' that fits the mounting stud, then you might be able to get it to crimp tight enough by using the next smaller size die in the crimping tool.

Or, if there is enough meat left on the lug, drill out the next smaller size to accommodate the 3/8" stud.

Thanks, Richard.

I tried the next smallest crimping die, and the wire still pulled out. The next smallest lug would most likely crimp tight, but the eyelet hole is too small and there's not enough "meat" to drill it out larger.

I think I'm going to try some lugs that specify "UL Listed", even though they may not be. I don't see any US Mfrd lugs on Amazon. Maybe an electrical supply house.

Thanks again, Mark

[richard5933]

Originally Posted by MSL

Thanks, Richard.

I tried the next smallest crimping die, and the wire still pulled out. The next smallest lug would most likely crimp tight, but the eyelet hole is too small and there's not enough "meat" to drill it out larger.

I think I'm going to try some lugs that specify "UL Listed", even though they may not be. I don't see any US Mfrd lugs on Amazon. Maybe an electrical supply house.

Thanks again, Mark

When I rewired my Airstream I scrapped all the imported lugs and went only with the ones that I found at the local electrical supply. They were more heavy duty and the crimping area was thicker material making for a much more secure crimp.

I also found lots of good terminals and lugs from Kaestner Auto Electrical who specializes in auto electrical supplies/parts. Not sure if you have a parts house like this near you.

[waninae39]

use a hydraulic crimper. get one with many dies so that they fit your wire size

cheap on amazon

[Mollysdad]

Originally Posted by MSL

I'm using this crimper: https://www.amazon.com/dp/B0B312RF9G...sin_title&th=1

and these copper lugs: https://www.amazon.com/dp/B0C96G27YL...sin_title&th=1

I have a similar crimper and the issue is the dies are not correctly sized for AWG specs. They are made to mm2, no matter what is stamped on the dies. What I had success with was to crimp with the "correct" die and if I wasn't happy, I'd use the next smaller size over the original crimp, rotating the work so as to avoid the "bunny ears" squishing out.
I'll continue to use mine, (I crimped 2AWG wire for my battery disconnect) but 'The Explorist' who has a lot of good factual information on YouTube recommends a different type, sometimes called a 'hammer crimp'. Frankly I like mine better, but he does it for a living so.....
There's only one set of jaws and a big lever.

[MSL]

Originally Posted by Mollysdad

I have a similar crimper and the issue is the dies are not correctly sized for AWG specs. They are made to mm2, no matter what is stamped on the dies. What I had success with was to crimp with the "correct" die and if I wasn't happy, I'd use the next smaller size over the original crimp, rotating the work so as to avoid the "bunny ears" squishing out.
I'll continue to use mine, (I crimped 2AWG wire for my battery disconnect) but 'The Explorist' who has a lot of good factual information on YouTube recommends a different type, sometimes called a 'hammer crimp'. Frankly I like mine better, but he does it for a living so.....
There's only one set of jaws and a big lever.

Thanks, Mollysdad. (BTW, I have a daughter named Molly!)

I actually did try the next smallest die, and the wire pulled out. I even tried putting a non-insulated ferrule over the wire then crimping it with the next smaller and it pulled out. I could go 2 dies smaller, but then I think I'd really have the "bunny ears". Maybe I'll try that if nothing else seems to work.

I'm going to order some UL Listed lugs and give them a try. I'm running out of lugs anyway, so I need to order more.

Thanks again, Mark

[waninae39]

get one like this

[MSL]

Originally Posted by waninae39

get one like this

That's basically what I have.
Thanks, Mark

[MSL]

Originally Posted by Mollysdad

I have a similar crimper and the issue is the dies are not correctly sized for AWG specs. They are made to mm2, no matter what is stamped on the dies. What I had success with was to crimp with the "correct" die and if I wasn't happy, I'd use the next smaller size over the original crimp, rotating the work so as to avoid the "bunny ears" squishing out.
I'll continue to use mine, (I crimped 2AWG wire for my battery disconnect) but 'The Explorist' who has a lot of good factual information on YouTube recommends a different type, sometimes called a 'hammer crimp'. Frankly I like mine better, but he does it for a living so.....
There's only one set of jaws and a big lever.

I forgot to mention that I have a tight place to crimp one cable, and the "Explorist" model looks like it would be difficult to use in this application. Although, it looks like it would crimp anything and everything!

Also, I found some UL Listed lugs that have a slightly smaller ID and slightly larger OD than what I have (at least they claim to), so I'm ordering those.

Thanks again, Mark

[jeffmc306]

MSL, I needed a smaller crimp tool for tight spaces and found this iWISS AP-50BI that handles #8 to #2 AWG although I use the TEMCo dieless lug crimp tool that Mollysdad suggested for #2 and larger.

As others have said, stick to UL rated lugs and match with the appropriate crimp tool.

Good luck!

[MSL]

Originally Posted by jeffmc306

MSL, I needed a smaller crimp tool for tight spaces and found this iWISS AP-50BI that handles #8 to #2 AWG although I use the TEMCo dieless lug crimp tool that Mollysdad suggested for #2 and larger.

As others have said, stick to UL rated lugs and match with the appropriate crimp tool.

Good luck!

Thanks, Jeff.

I'm going to give the WISS AP-50BI a try once I get my UL Listed lugs.

Mark

[G8trwood]

FTZ power lugs or equivalent have always worked well, boats, offroad and RV. A bit pricey, but electricity and a high vibration environment. What could go wrong.

[rwnash]

MSL

Hope that you find lugs that work. I try to avoid buying things from Amazon; while they seem to have everything at a low price it may not be the bargin you want. Cheap tools can be just that. My go to source is McMaster Carr; good selection and the best web site for finding the exact part you need. My experience for almost any job is that you really want a high quality part designed to fit - not something close enough or adapted to work. This is especially true for plumbing & electical. (Don't get me going on imported stuff from the big box stores.)

While it is supposedly not "approved", a little electical solder (63/37) between the stranded wire and lug seems to help; been doing it for years with no problems.

Good Luck

Whit Nash

[Mollysdad]

Finding lugs was the hardest part of my Battery Disconnect project. Some needed a 3/8 hole, some a 5/16" hole, some needed a 90º angle. I tried to find one's made by Panduit, but that didn't work. One seller had exactly what I wanted but I had to buy 500! Another vendor required me to fill out a three page form? Government contract??
This is the crimper I used. Yes, Amazon, and I love tools, but I can't justify a big expense for a project I did once.
AWG is American Wire Gauge, while the rest of the world uses mm2. They don't equate, exactly.

[MSL]

Originally Posted by rwnash

MSL

Hope that you find lugs that work. I try to avoid buying things from Amazon; while they seem to have everything at a low price it may not be the bargin you want. Cheap tools can be just that. My go to source is McMaster Carr; good selection and the best web site for finding the exact part you need. My experience for almost any job is that you really want a high quality part designed to fit - not something close enough or adapted to work. This is especially true for plumbing & electical. (Don't get me going on imported stuff from the big box stores.)

While it is supposedly not "approved", a little electical solder (63/37) between the stranded wire and lug seems to help; been doing it for years with no problems.

Good Luck

Whit Nash

Thanks for the thoughts and info. I agree with what you're saying ... sometimes I follow it, sometimes difficult to justify. I have used McMaster for some things; great source.
Mark

[MSL]

Originally Posted by Mollysdad

Finding lugs was the hardest part of my Battery Disconnect project. Some needed a 3/8 hole, some a 5/16" hole, some needed a 90º angle. I tried to find one's made by Panduit, but that didn't work. One seller had exactly what I wanted but I had to buy 500! Another vendor required me to fill out a three page form? Government contract??
This is the crimper I used. Yes, Amazon, and I love tools, but I can't justify a big expense for a project I did once.
AWG is American Wire Gauge, while the rest of the world uses mm2. They don't equate, exactly.

Yes, I have the same problem to some extent. There used to be more local sources; not so much these days.

I'll post after I get my new lugs and crimp tool.

Thanks again, Mark

[JeffKim]

Maybe repeating for emphasis, but I ordered specific lugs for the wire and terminal diameter I needed; not an assortment and try to make them work. I got them off Amazon and they are 100% copper and I didn't think there were any quality issues. I used a primitive hammer type crimper which seemed to do the job.

With smaller diameter wire (10AWG and less), I bought a ratcheting crimper specifically for heat shrink terminals and since I was doing a lot of 10AWG something like these terminals.