ᐅ Buying Replacement Screws for a BILLY Shelf – How Do I Find the Right Ones?

bobar47 schrieb:
I would appreciate it if someone with experience could share their input.

Hello,

I would like to go into more detail regarding screw sizes and types, as even the smallest differences can greatly affect the assembly quality of furniture like BILLY.

BILLY shelves are made from particleboard, which requires a specific type of thread: particleboard screws have coarse threads that grip well into the compressed wood fibers without damaging the material. Most of the screws needed are Phillips head screws sized 4 x 35 mm (approximately 5/32 x 1 3/8 inches) for the sides, and 3.5 x 16 mm (about 9/64 x 5/8 inches) for thinner parts such as the back panel. The length is chosen to avoid piercing through the material while still providing good holding strength.

When purchasing replacements, I recommend paying attention to the following factors:

1. Thread type: particleboard screws with coarse threads.
2. Head type: usually pan head screws that sit flush with the surface.
3. Material: zinc-plated steel to prevent rust.
4. Length: as described above, not too long for thin parts.

If you don’t have the original screws, there are specialized screw kits for IKEA furniture available from hardware suppliers that fit exactly.

Finally, may I ask: Has the shelf already been assembled, or are you just starting? This is important to know in order to avoid damage caused by using the wrong screw size.

Laukau5 schrieb:
Finally, may I ask a follow-up question: Has the shelf already been assembled, or are you just starting?

Thank you for your detailed post. The shelf is already fully assembled; I have just lost some screws or they fell out. Therefore, I need replacements to secure the shelf properly again. However, I don't know the exact screw sizes used during the original assembly, so I'm trying to check as precisely as possible based on the information provided here.

bobar47 schrieb:
How do I find the right screws for a BILLY shelf if I no longer have the original packaging or assembly instructions?

That sounds really frustrating, especially because this type of screw can’t just be replaced with any random one when it comes to stability. I had a similar issue where I wasn’t sure if the hardware store even had the right small parts for my shelf.

My advice is to first measure the existing hole diameter and the screw length as precisely as possible, if you still have some screws left. If not, carefully disassemble a part and try out different screws to see what fits. By the way, I ordered a screw set specifically designed for IKEA furniture, which helped ease my uncertainty.

I hope you find the right screws quickly—that really makes everything easier! 🙂

bulanau schrieb:
Important: Always pay attention to tolerances, otherwise material failure may occur.

I fully agree with that. Adding a bit of technical advice: when installing screws, make sure to respect the torque limits, especially with already assembled shelves. Over-tightening can weaken the particle board before it actually holds better.

If you’re using a cordless drill, set it to low speed and apply controlled force. Some also recommend pre-drilling a pilot hole, particularly for thin back panels.

I hope these details help you, bobar47.