I have a customer who is set on having two large pantry doors in place of 4 (on 2 cabinets side by side). I have attached two photos, he wants to match the doors in the picture but with solid wood flat panel doors. I'm not really sure how to approach this. I have built passage doors before that have held up well and stayed flat but I'm now expert and the method I used was painfully slow. But here I need the upper and lower doors to stay on the same plain.

My suggestion was to use 1/4 sheets for the panels as in the picture just for ease and weight then I could use all the same hinges. But he wants solid wood.

I am considering laminating the frame parts and then taking them down 1 3/16" and using blum thick door hinges (I have never used these before) also making the upper doors the same thickness. The barndoor "x" would have to be true divide for the panel which might help with twist?

My concerns are making sure they stay flat and also if the hinges would hold up.

I have always admired the massive doors some of you have posted here.

Any recommendations on construction methods for these doors?

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Your method sounds ok. I think you should make the stiles and rails a little wider than the picture. Also may be add some extra hinges on the long doors.

Yes, I was thinking 3 1/2" for the all, stiles rails and x braces. I am considering 5 hinges ea. evenly spaced?

I forgot to mention the doors will end up around 31 1/2" x 72.

I am thinking of laminating 3 pieces up to hopefully keep the frame from bowing. I have had mixed results with this just using Titebond original. Should I consider something else?

Love it when the customer tells you how to do your job...of course when it fails it's on you, you should have known better.
I'd bump them up to net 1 inch thickness adding a 25mmx50mm domino loose tenon in each joint, 1/4" mdf core 2 sided panels with 5 hinges per door.
Add Hafele panel straightener on pull side to maintain flatness if necessary.

Make passage doors 1 3/8 thick. you will never have a problem. Use hidden mortice hinges. 3/4 doors were never ment for this application.

I have the same reaction as Jim in that the customer does not in any way shape or form dictate to you what the manufacturing spec's are. We all come against this when we want to please the customer or want the work, but you should make all the issues clear and in writing, signed off on by the customer. Potential panel movement, solid wood construction with narrow rails/stiles and wide panels, and so on.

I would never run a full 1 3/8" thick passage style door in that application. Too heavy and plenty of other issues.

Hopefully the customer knows his spec' equates to some pretty spendy doors (which may not be the case based on the reference image).

I made some tall doors for a walk in pantry similar to this project. 1" thick stiles & rails, 3/4" raised panels. I used 5 Blum thick door hinges per door, and mounted them to a jamb I built similar to a pre hung passage door. I spoke with the homeowners recently, and they said the doors are still working well almost 10 years since they were installed.

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Here is a couple of doors that I made. They lead into a pantry but the client wanted them to look like cabinet doors.
The rail and stile are 1 1/8 inch thick. I used a pair of Sagutsune hinges on each door. A pair has a rated capacity of 80 lbs and the require a 40 mm cup. These are springless but spring loaded are available. With no stop on the bottom of the door I was concerned that spring loaded may make it difficult to keep doors aligned. An MDF 3/8 reversed panel. They have been in 6 months and are still aligned

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