Does a 5/16 ring terminal or lug fit on an m8 stud?

How ugly is it to put a 1/4" lug on a m6 post?
How bout 1/4" lug on a m6 post?
1/4" lugs would streamline my BOM.
I'm thinking ADR21 or ADR25 or ADR21-AR or ADR35-AR
I would like to go with adr https://ecat.eleknet.com/PIM_Docs/Docs/STEP_ASSETS_PDF/74913820.pdf
I have not decided on the battery yet but its my understanding that most of the "big gulp" prismatics have m8 posts.

I have a victron lynx power in and just tested two different lugs from pv-cables. The 5/16 fits better than the 3/8. There is too much slop with the 3/8. I was surprised that the 5/16 fit, but I guess they make it with enough tolerance for the 5/16 lug to fit m8 bolt

Yes 5/16 and 8mm are very close to the same size.

Ampster said:

Yes 5/16 and 8mm are very close to the same size.

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Is there a chart that shows what lug fits on a M? bolt?
I ask because looking at Victron equipment I see M8 bolt but no SAE equivalent
Example: Victron SmartSolar MPPT RS 450v 100A shows a M8 bolt for the battery connection
A chart would make it easier for a DYI person to assemble and order the correct battery lugs.
Thanks
Scat

Scat said:

Is there a chart that shows what lug fits on a M? bolt?

Click to expand...

Yes, I just Google it on my phone.

Ampster said:

Yes, I just Google it on my phone.

Click to expand...

I searched and found 2 charts
1) From Selterm
link: https://www.amazon.com/gp/product/B...&linkId=2eb5709ddc34351c2f5716743e004d76&th=1

2.) From FSP
link https://www.walmart.com/ip/6-AWG-10...3?wmlspartner=wlpa&selectedSellerId=101001238

I compared each chart and wire and lug are the same
I hope this help someone.
Thanks
Scat

The difference is trivial. 8mm sockets are interchangeable with 5/16. There is usually more difference in production tolerances, so the sockets from one system of measurement might fit better on a nut or bolt from the other. Same with 19mm and 3/4. Other sizes often work too, but the difference is more significant. Well, 7/8" is 22.2mm, so 22mm and 7/8 can be substituted either way too. That 0.2mm is about .008" or less than 1%.

This might be a good thread to ask my question.

I originally built my RV system as a novice. 3 battle horns and 2000watt inverter. 250A ANL fuse. Learning more over time, I see I should have gone Class T.
I added 3 more batteries but no more load, just more storage.
With my new (internet) knowledge I decided to swap the ANL for a ClassT.
The class T bolts are 3/8”. The ANL are 5/16”
I used Anchor quality lugs in the original build and the ‘flats’ are as big as the nut and washer of a 3/8” bolt.
I don’t want to make new cables.
Can I just clearance the holes in the lugs or is there something else different about them?
I still won’t need above a 250amp fuse

The charts above show the flat area width and thickness are the same for the two hole sizes