Reply by Colin

One more thing, you probably checked this but just in case…

You need to use kiln-dried wood for your core, otherwise it will expand and contract too much and can cause checks in your face veneer.

Also, it is usually not a good idea to use softwood as a core for hardwood faces. Poplar is a good choice if it is interior. You can also use generic mahogany if you have a source that sells it cheap.

These problems are more of an issue when doing exterior doors but it can effect interior doors as well.

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