I'm with Poppy. My Umpqua scale goes to 30 grams or about 450 grains, not nearly enough if you want to make lines for most 2-handers. It is also not very precise. It might be good to the nearest 10 grains at the lower end of its scale, but at the upper end it is hard to read to the nearest 20.
The Umpqua scales can be useful though if you just want to sort sink tips, single-handed shooting heads, etc.
Aaron and Poppy both have the scale you need, I would also add one more item. Al Buhr's line building booklet, which both of the aforementioned have. Ablut $50 (shipping included) gets you what you need to get started.
May be a good idea if they are packaged as kit. Either way you can't lose.
I sell such a kit. It includes Al's line splicing book, grain scale, and my line splicing kit upgraded with the big pin vise. I call it Poppy's Deluxe Line Splicing Kit. It can be found on my line splicing and loop making webpage.
I second Poppys scale. I bought one last fall and I use it all the time. It will tare itself with whatever you want to use for holding a line or containing something you are trying to weigh. I measures in Grains/ Grams/ Ounces, and will do a count for you too. I used if for counting things like hooks...you just weigh one hook then calibrate it to 100 or 50 or whatever number you want....start dropping them in and it will let you know when you reach the target number.
I also use it for weighing my shot patterns for centrepin fishing too....I know I know this is a fly site, but I still pin the winter months here, and I am just trying to show how many functions the scale has.
well, there's also the guesstimate approach. for building tips and lines from normal fly lines just estimate from the aftma scale and come up with a grains per foot. I'll never forget that an 11 wt is 330 (11 grains per foot for 30 feet) and descending from there it goes down 50, 40, and finally 30 grains for 10, 9, and 8wts, and I have no reason to build a line using anything lighter than that. 12 wt is 50 more than 11.
Now if you really need to measure a spey line out of the box you need a scale, but you should know the weight of the line out of the box. For taking sections out, just mic it, and compare to other lines you know the weight per foot of, and once again guess.
Just remember that the line weights aren't precise. The acceptable range on a 30 foot line is something like 5% in either direction. I don't know what it is for a spey line, but you get my point. No need to sweat the details since when you open the box your 30 foot eight weight could be any where from 200 to 220 grains, and that's if it's within acceptable limits. You really think they're all within acceptable limits
So sure, if you've got $20 with nothing better to do hanging around, get a scale. Other than start you down a very expensive road of line tweaking, it won't do any harm:beer2: