ᐅ Has anyone ever tried using heavy-duty screws for Kallax units?

Created on: 12 Jun 2024 18:07
K
kurigla
Hello everyone,

I plan to load my Kallax shelf more heavily than usual, including with some heavy binders and electronic devices. I’ve noticed that the original screws are sometimes considered a weak point when the shelf is under greater load. Has anyone tried using reinforced screws, such as thicker ones or made from stronger material, to increase the stability of their Kallax?

I’m interested in whether this is practically feasible, which types of screws are suitable (e.g. metric instead of wood screws, stainless steel, galvanized, etc.), and whether this actually results in a noticeable improvement in stability.

It would also be helpful to know if the assembly becomes more complicated or if there are any considerations regarding the hole pattern or material compatibility of the Kallax.

Thanks in advance for your experiences and advice!
D
DUVIN
13 Jun 2024 08:12
I tried using galvanized M4 × 35 screws with washers for better load distribution. Pre-drilling is essential. Result: Stability improved, assembly time slightly increased.
K
kurigla
13 Jun 2024 12:05
Thanks for your specific feedback!
klo61 schrieb:
I also recommend pre-drilling to prevent cracking.

I will definitely do that.
usbla schrieb:
Use threadlocker (Loctite) to prevent screws from loosening.

That sounds good. Do you have a recommendation for the appropriate strength? I don’t want the screws to loosen due to vibrations, but also want to be able to remove them if necessary.

Regarding the load: I plan to store heavier boxes in the lower section and a few binders above, nothing extremely heavy but certainly above the usual Kallax weight. I was thinking of M4 × 35 or 40 screws with washers, plus metal brackets on the frame. What do you think?
F
Franck
13 Jun 2024 13:50
Loctite medium strength (e.g., the blue variant) is ideal for furniture. It prevents loosening but can be removed if needed. M4 × 35 (4 mm × 1.4 inches) fits well for Kallax. Metal brackets also help improve overall stability.
A
Ankeli
13 Jun 2024 14:16
I also used reinforced screws, but M5, as I find them a bit stronger. Pre-drilling is absolutely necessary; otherwise, the thin material will crack. Metal brackets are helpful, but for aesthetic reasons, choose more discreet ones.
K
kurigla
14 Jun 2024 08:43
Thanks again to everyone who responded in such detail. In summary, I will consider the following points for the modification:

- Metric screws (M4 × 35–40mm (1.4–1.6 inches)) made of stainless steel or galvanized steel
- Pre-drilling with an appropriate drill bit
- Use washers to avoid putting too much stress on the material
- Medium-strength threadlocker (blue Loctite)
- Metal brackets at critical points for additional stability

If anyone has further advice on installation in combination with the metal brackets, feel free to share!
U
usbla
14 Jun 2024 09:15
kurigla schrieb:
Notes on Installation in Combination with Metal Brackets

It is important that the metal brackets are fastened with screws sized appropriately for the Kallax wood—use the existing pre-drilled holes or adjust them accordingly. The brackets should not be too large and should be placed at the corners where the greatest load is expected.

Sometimes it makes sense to secure the brackets with two screws per side to significantly increase stability.