Looking for suggestions for a Gun cabinet (solid panels or Frame and Panel)

Depends on design? Suggest using both, solid wood and frame/panel.

Wood movement with the grain is negligible. It is the radial and tangential movement that creates issues.
Using 12" walnut sides, I would have no issue with solid wood for sides and shelves.
Normal movement range between 8-12% moisture is only ~1/8" for walnut. Plus the entire cabinet carcass will move same way.

The issue is 48in wide back and doors to cabinet.
Solid wood back needs to be half lap or tongue-groove joinery; with allowance for expansion between each board.
For the front doors, Suggest using frame and panel as best option. A solid panel will be hard to keep flat over time, and it will change 1/2" for same 1/8" change in the 12in sides?

YMMV

My suggestion is when you build something new and the wood is precious or expensive first build the piece in a less expensive wood.
But that doesn't really work anymore all wood is expensive.
Working out the details and making mistakes in a less expensive wood is the point.
When walnut is completely dry is very stable.
But that doesn't mean you can abandon a project for weeks or a month.
Once you start don't stop.
Good Luck

If you know how to use a digital drawing program, I'd highly recommend that you get a drawing done and have the customer sign off on it. People who dive into this sort of project without any real knowledge are nightmare customers, specially since he's realized he can't and now might be expecting you to be a miracle worker. I've been there and done that, trust me it's not worth the damn t-shirt.

Frame and panel is more work on your end but it's also a "safer" construction and IMO, it looks nicer. If I were in your shoes, I'd probably show him some photos of frame/panel pieces and explain how it allows for movement and how solid panels don't. Then let him make the call.

May I offer a suggestion. Do not put a glass door on the cabinet. It's an invitation for people to snoop where they have no business. In this day in age, no one needs to know what someone has in the way of guns. Keep a good inventory stored somewhere else in the house and don't talk to others about your guns! It only invites thieves and the ATF.

Solid wood back needs to be half lap or tongue-groove joinery; with allowance for expansion between each board.

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Or, use plywood for the back.

For the front doors, Suggest using frame and panel as best option. A solid panel will be hard to keep flat over time, and it will change 1/2" for same 1/8" change in the 12in sides?

Click to expand...

I agree. Use frame and panel for the doors regardless how you build the carcass.

well im with bob,id never store my guns in an easy to open cabinet these days.but to answer your question id definitely go frame and panel.as for the back go with walnut ply,no need to waste all that walnut for the back. but hey if he's paying and wants solid just advise and do what he wants.

other than sideways it looks great.solid panels just wouldn't have looked good.