I have an empty spod reel spool which has a 300m capacity for 0.35 mono
I have 275m of 0.23 braid to load, I have some cheap mono to use as backing, how much backing do I need ? Backing mono is 0.35

Thank you

In reply to Post #1
181.2m of backing according to Grok

In reply to Post #2
Perfect thank you 👍 who's Grok ?

Grok (Which is Elon Musk's / Twitter AI) is correct.

I worked it out at as 181.24m @ 0.35mm

Quick question as I have a similar quandary - how are you going to measure the back line going on?

It is simpler to wind all the main line onto an empty spool, then fill the spool up to the lip with backing. Next wind this all onto a spare empty spool, then reverse wind it back onto the reel.

In reply to Post #5
Berkley line counter.

In reply to Post #6
For the poor schmucks amongst us who dont have a bundle of spare spools you can easily do a similar thing, but it's a bit long winded to explain...
Add your new line onto your spool, add a piece of tape to finish off, then top up with your spool with your backing.
Now use a drill to spin off the backing onto an empty bulk spool. Then remove the new mainline onto another empty bulk spool. Now put the backing onto the reel spool. Add a wrap of insulation tape around the middle. Now transfer the new mainline from the spare bulk spool onto the reel spool over the backing, and its done.

In reply to Post #8
What a palava 🤪I'm thinking I'll measure 1m of the backing see how many turns of the handle it takes then times that by 180, that should be there or thereabouts ...I hope

In reply to Post #9
but don't forget the amount of line will increase with each rotation as the circumference is increasing as the line builds up

Look up pattaya fishing.net advanced fishing line calculator it works well. I calculated it to 181m. You need to find how much line is put on by 1 turn of the handle.

In reply to Post #9
But accurate

I assume the 181M plus braid will fill it to max capacity, isn't it still the done thing to slightly under fill when using braid?

In reply to Post #13
My input would be to install the amount of braid onto a spool first, then the backing to the desired amount to fill the spool to your requirements.

Take this spool off your reel and put on an empty spool.

Wind the backing only on from the first spool onto the new spool, measure the diameter with a digital caliper ( vernier caliper for us old uns) take note of the diameter.

Then load you remaining spools with backing till it reaches the above previously noted diameter and them add your braid.

I have done this several times over the years and have the diameters off backing needed on my spools for different diameter “main” line.

Then when I re spool i can refer back and alter the backing accordingly.

In reply to Post #13
Exactly, definitely not what you want. If you use the loading braid then backing, taking off then putting back on method, then just use a old line spool and drill to take it off your reel spool, you don't need a spare reel spool for that method. Nowadays I use something like these for all my reel loading/unloading work, makes life so much easier.

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