So the wonderful folks at Ikea discontinued the (mostly 1"x4" soft pine wood) GORM series shelving units and replaced it with the (mostly 1"x3") HEJNE series shelving units. The design overall is identical, just the width of the wood is different which impacts overall depth dimensions. Both shelving units have either 3 slats or 5 slats. The GORM had ~15" and ~24" deep shelves while the HEJNE shelves are ~12" deep and 18.5" deep sitting on ~1.5" x ~1.5" cross brace at each end to complete the shelf using lag screws/bolts to attach the shelves to the upright posts (also 1"x3" or prior 1"x4"). The deeper 5-slat HEJNE shelf is rated for 110LBS/50KG. One could easily modify one or both ends to use a 1.5"x3" (2x4) ends instead for added strength and support for those front mounted hard drive heavy laden servers. So yeah, the perfect dimensions for a server rack. The vertical spacing is a touch (~3/8") taller than 2U (=3.5"; 1U=1.75" - if you didn't know) between mounted shelves (so 2U, 4U, 6U, etc). Enough room to pinch fingers and jam up on thicker power cables that might get in the way using just the ~2U spacing (yeah, rack the server first, then plug in the cables). You gain ~1.5" when used with 4U servers.
Of course, being made of wood makes it very easy to modify as well, with additional cross bracing, custom/home made wood, plywood, or steel doors and panels, and making a caster wheel base would require stronger/stiffer uprights or angle iron for added strength.
Each HENJE upright post is US $3 (or $6 for set of 2) and each ~19"x30" HENJE shelve with hardware is US $7 (or $14 for set of 2), $5 for the wire cross brace, and $2 for the plastic boots ($1 for 2 boots). Excluding taxes, I have a 6-shelf unit for about $60. Avoid 45° grains and knots right at the ends where lag screws go - they tend to crack, split, and break.
Of course, being made of wood makes it very easy to modify as well, with additional cross bracing, custom/home made wood, plywood, or steel doors and panels, and making a caster wheel base would require stronger/stiffer uprights or angle iron for added strength.
Each HENJE upright post is US $3 (or $6 for set of 2) and each ~19"x30" HENJE shelve with hardware is US $7 (or $14 for set of 2), $5 for the wire cross brace, and $2 for the plastic boots ($1 for 2 boots). Excluding taxes, I have a 6-shelf unit for about $60. Avoid 45° grains and knots right at the ends where lag screws go - they tend to crack, split, and break.