Ok- two questions, and this may seem stupid but I genuinely don't know.
1. How do I sell my weapons?
2. Can you make grips/guards?
2) It is planned, but currently, no. - You buy grips from either shipping (window/chart near anvil and forge) or from partsmith Geofrey
when you buy from geofrey, there's a really uber cheap 1h/2h grip (1$/2$ respectively) however - Bear in mind you need to be verrrrrryy delicate shopping at his place currently
Use his shopping basket, and carefully set the grips inside, crouch, and pick it up gently, and then uncrouch and carry it out when you're ready
If you mess up, or decide one of the grips isn't affordable for you - Give up, and put the rest back too - If you have a pricing error - it'll ding you and call you a thief and mark all the grips as stolen (not entirely true, it might only mark a couple, but still), once the items are stolen, they're stolen forever.
1) you'll need to hand your weapons to NPCs who request them - you can set up some of them behind the tapestry on your counter, handle side in, and the NPCs will usually see them from the first and second shelf
If you haven't seen how to open shop yet, there's fine print on the door - you have to click the actual "Shop closed" plaque ontop of the door to change to open, just opening the door won't do it for npcs to come in.
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when You're selling just copper, it can be hard to make each day seem profitable and progressive - but I assure you, it won't always feel that way, copper is just the slowest tier (that said, I've been having trouble myself in 0.0.82 getting NPCs to desire my most expensive metal...)
The Main reason copper's so hard to progress through is because its so "cheap" and grips and guards are still required, almost as expensive.
Where a great sword gets you maybe 50 or so $, and costs about as much to make in copper
A great sword in tin is 1500 for the tin, and only 20ish for the rest - 10% of 1500 (mark up) is 150 -> easily paying for 4 more grips/guards, ontop of a replacement 3 tin
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Do not close the lid of the shopping basket, btw.
Well. You can, just don't have it lidded when you leave - it will trap the items forever - when the shopping basket crosses the threshhold of the store, It swaps the basket for a regular crate, The items inside must be free if they're to remain usable -
IF they're locked in the "Shopping basket" - That's what they'll remain because the "Shopping basket" erases itself from existence as it swaps out for a crate, leaving "Locked" until you "Unlock" the shopping basket, which doesn't exist to unlock.