Hi! I’ve only posted here maybe once, but I’m looking to change that and have been working to improve my joinery.

Specifically, I recently had the geometric realization that adjusting the horizontal angle on my miter saw is one of the least precise adjustments I can make, when trying to make two cuts that add up to 90 degrees. So instead, I now set the angle for the smaller angle, make the first cut, then set the workpiece for the second piece using a square against the fence. Basically, I’m rotating the piece so it’s 90 degrees to the saw fence, and that lets me cut the complementary angle without realigning the saw angle.

The new problem is that because I’m still using slightly-warped and slightly-twisty stock, the surfaces aren’t terribly great for gluing up. In one case, I glued up one end of a diagonal brace but the other end was lifting up, off-plane. Hand sanding with a block helps, but more often than not, I end up rounding off the edges and glue leaks out. So I’m now seeking recommendations for a small hand plane, so that I can have better, flatter surfaces to glue together.

Is this the right approach? If I’m mostly working with narrow stock like 1x4-inch, is there a correct-sized hand plane to smooth out an end-grain on that small of stock? Apologies in advance for not really knowing all the right wood terminology. I’m still learning.

Ideally, I’d like to buy something that will be versatile and serviceable for a long time. So cost isn’t too important, but ideally it’d be proportional to my (few) other tools. If I know what to look for, I’ll keep my eye out for such a specimen while at the thrift store.

EDIT: To clarify, a use-case would be if I’m gluing a diagonal brace at mid-height of a post. If i had a plane, I could work the post so that it has a flat face, so that the brace won’t deviate left/right. For the diagonal brace itself, I can mostly trust my miter saw to cut the angle reasonably plumb.

EDIT 2: Might I actually want a card scraper instead?

EDIT 3: y’all are awesome and I now have a fair number of suggestions to consider. I guess there goes all my disposable money for September, once I go visit the nearby woodworking shop.