Every part of the kit is stronger than our 50 lb limit — with the 3× safety factor already applied.
The Pull-Out Board Kit maximum load is 50 lbs, evenly distributed on both sides of the board.
Every fastener, bracket, and rail in the system has been independently calculated against real engineering standards.
Select your configuration below.
The default below is the worst case: 22" over-travel slides — the longest we ship and the largest moment arm. The slides are rated 100 lbs, twice the kit's 50 lb limit.
What 50 lbs looks like (approximate weights)Workshop: two cordless drills with batteries (8 lbs), an impact driver (3 lbs), four spare batteries (6 lbs), a hammer (1.5 lbs), a dozen screwdrivers and pliers (6 lbs), six small bar clamps (9 lbs), tape measure, square and levels (4 lbs) — about 38 lbs. Craft room: 100 thread spools (8 lbs), 20 rolls of ribbon (5 lbs), four pairs of scissors (1.5 lbs), a rotary cutter and rulers (3 lbs), a small parts drawer on the bottom shelf (10 lbs) — about 28 lbs.
🤖
This load analysis was performed by Claude (Anthropic),
an AI assistant, using NDS (National Design Specification for Wood Construction) engineering formulas
with a 3× safety factor applied to all fastener capacities.
iCalculation methodology
Bending moment: M = F × (arm + travel/2)
= 48 lbs × 33.75" = 1,620 in·lbs (22" slides)
Horizontal tension (top rail):
H = M ÷ rail height
Lag screw withdrawal (NDS): W = 1380 × G¹·⁵ × D × L
D = 0.242" (#14), L = 2.42" embedment
1 bracket per stud · SF = 3×
Bottom rail — direct bearing:
Rail bears in compression against wall/stud · vertical load carried by bearing contact, not the screw
Bottom screw (#14×2") resists lateral drift only · SF = 3×
Rail weight (2 lbs) deducted from all payload calculations.
Slide capacity = manufacturer's stated rating.
---lbs
Calculating...
⚡
What fails first — and why that's a feature, not a flaw
Why the wall bracket is stronger than it looks
The Biaungdo 18×21mm bracket appears small — but size isn't what determines strength here.
Geometry is. The bracket's vertical leg sits completely flat against the wall,
so the wall itself provides a continuous reaction surface. The bracket never bends —
it transfers load in pure compression on the 2020 side and pure shear/tension through the lag screw on the stud side.
VitaReach uses one bracket per stud on the top rail.
Each bracket is secured with a #14×3" heat-treated structural screw
with a 0.55" washer head that fully covers the bracket's oval slot —
rated by NDS formulae with a 3× safety factor built in.
What each part actually sees at rated load
Every component — weakest to strongest
How we calculated this
The kit forms a rigid rectangular frame — top and bottom arms of equal length, connected
by the vertical spine, with the board riding on ball-bearing over-travel slides that travel 1.5" past the slide length.
A distributed load has its center of gravity at arm + half of travel from the wall —
~33.75" with 22" slides (22" arm + half of 23.5" travel).
This creates a bending moment M = Load × 33.75" that the frame resists as a horizontal force couple:
the top rail is pulled away from the wall (tension), the bottom rail is pushed into it (compression).
The force on each connection is H = M ÷ rail height — which is why a taller panel height
means lower stress on every fastener.
Vertical weight (load ÷ 2 per rail) is carried by direct compression bearing — the bottom rail presses flat against the wall/stud, the same low-risk compression geometry as the wall-side bracket above. The #14×2" structural screw (T30 Torx drive) at this joint isn't in the vertical load path at all; it only resists small lateral (side-to-side) drift, since the bearing contact — not the screw — carries the rail's downward thrust.
All fastener capacities use NDS (National Design Specification for Wood Construction) formulas
with a 3× safety factor applied throughout.
Lag screw withdrawal: W = 1380 × G1.5 × D × Lembed.
The #14×3" LIONMAX structural screw has D = 0.242" thread diameter and a 0.55" washer head
that fully covers the 12.5mm bracket slot. Thread embedment into stud: 2.42"
(3" screw minus ½" drywall minus bracket thickness).
All calculations assume over-travel slides at full extension.
Spine joint — how the two 2020 rails are held together
The spine is two 2020 rails joined side by side
The kit's vertical spine is made of two 2020 aluminum rails placed side by side,
forming a combined 20×40mm section. When joined, they create a closed torsion section
that is stiffer in twist than a hollow 2040 V-slot profile — by approximately 27%.
The two rails are connected by four flat 2-hole joining plates —
one on each face at the top, one on each face at the bottom — using M5 bolts into T-nuts.
This gives 8 bolts total, on both faces, at maximum lever arm spacing.
Plates per spine
4 plates
2 at top · 2 at bottom · both faces
M5 bolts per spine
8 bolts
2 per plate · with Loctite 243
Safe joint capacity
1,499 lbs
8 bolts × 10,000N each ÷ SF=3
Actual joint force
—
at rated load · varies with spine length
Bolt utilization
—
at maximum plate spacing
Safety margin
—
above rated load
📏
Plate placement rule — one simple instruction
Place the joining plates within 40mm (1½") of each end of the spine.
That's all. No measurement needed beyond that — closer to the end is always better.
At this placement, the joint spacing is nearly the full spine length,
reducing bolt forces to less than 6% of their capacity at 50 lbs.
The bolts are essentially unstressed. The Loctite 243 on each bolt
prevents any loosening from the cyclic load of daily board use.
Load ratings assume installation into solid wood wall studs at 16" spacing — not drywall anchors.
All hardware must be installed per the VitaReach installation guide.
Ball-bearing slides are third-party components rated by their manufacturer; VitaReach makes no independent claim about slide capacity.
Fastener capacities are calculated per NDS with a 3× safety factor.
Actual performance depends on wood condition, installation quality, and load distribution.
This rating applies to static and slow-moving loads only.
Do not use for dynamic, impact, or suspended human loads.
The 2 lb weight of the aluminum rail assembly has been accounted for in all ratings.
