I haven’t heard of anyone adding a false front to a 45-degree sink base cabinet on-site. The main challenge with this is that the top and bottom panels are quite large and require precise machining on the CNC. Parts of this size can be difficult to hold down during horizontal boring for assembly holes.
If a false front were added, it would require a fixed shelf to secure the backer that supports the front. This additional shelf would significantly increase the cost of the cabinet without providing much benefit in terms of aesthetics or functionality. Most people opt to use the two doors as they are, which works well and keeps things simple.
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