If it is just the 1st 3 frets, you need to run a straight edge from bridge to 3rd fret, then 2nd,1st and nut, find your high points, file them down and dress them, most likely it is the 4th or 5th fret that is causing the issue, if you are running a low action, it doesn't take much extra height on 1 fret to cause some issue
Get your self a good straight edge, especially if you plan on making more fretted git's, I use an aluminum yard stick on its edge, use Frank's method for finding the high ones, you can try and file them individually if it's only 1 or 2, but sometimes after fixing one you find the next one or the....so on so on, I found a regular square file with no handle just resting it's weight on the fret board running the same direction as the neck, slide it up and down the frets as even as possible and from left side and middle and right side, no down pressure, the weight of the file takes them down, you'll see the shiny spots that are high and the untouched spots that are low, you do this till all are even when checking with your flat edge, then you have flat frets, now you need a fret file to re-curve them and then polish them with some ultra fine sand paper. This is what is known as the fidly part of CBG's
meant Daryl's suggestion, not Frank, your Frank Duh!
no no no, not on the saddle, just the neck, I'll have more info for you in the a.m.
You can get a really cheap re-curve file(crown file) on ebay cheap, they work, otherwise you'll just have some flat spots on your frets, still works, just not as pretty or as functional if you have to take a lot off, but get a straight edge (long-2" or longer) to properly check the frets from one to another. And your only checking from the last fret to the first fret, not the nut or saddle, but you also need to be mindful of the minimum proper string height as well, if your saddle is lower than your nut, that will cause issues as well, have any pics of your build???
cheap file---> file
Ok started filing a few frets that were rocking when I used a 3 frets at a time rocker. Some are really flat and had to go back over as one effected the other as you said. Haven't restrung it yet to see if it helped. The file I will get as it looks to help. Old jewelry box with flakey paint paper applied. Thanks
to aide in getting it to play properly with minimal buzz, make sure your height at the first fret is somewhere around 1/32nd to 3/64ths, and at the 12th fret approx 5/64ths. It's also ok to have a tiny amount of neck bow (lower) in the middle around the 12th fret after string tensions are at their norm when tuned.
Do you have the ability to upload pics? If so, I would want you to take some pics at a side view and top view of the neck.
Start at the nut, first off, I would like to see a pic, or at least a description of the angle the string takes over the nut, to the tuner head. Measure the height at the first fret to the bottom of the string, then again, same measurement at the 12th and then the 17th fret, also, want to know the kind of angle from where the string crest over the saddle/bridge to whatever your using as a secure point for the strings. Also, what gauge string are you using, for your "G" tuning, and what is the scale length(nut to saddle)
It's a lot of information to provide, but I'll be glad to help in any way I can till we get it straightened out, plus, what did you do to lead up to this point prior to installing the string.
Also, sending you a friend request so I can privately message you.
Also, after rereading your previous post with pic, your using the right file, but don't try to repair one fret at a time, like I previously said, you slide the file up and down the fret board, not pressing down, it's own weight of the file is enough, and when you see shinny flat spots, it's working, but you can't stop until the whole and all frets are shinny, that's when you use the re-curve file to reshape them, I know you said you don't have that file yet, seriously, eBay and get one, cheap cheap but will take a little while to get.