The following is a curated selection of stores where I bought components for my 3D printers together with a short "buying experience". I hope it helps.
By EU I mean unified market (sorry UK). Suggestions are welcome. Random order.
Good filament selection, bondtech and phaetus reseller. Good as it's easy to reach the free shipping tier.
Good selection of filaments and spare parts. Their flex plates are decent. Also PrimaSelect filaments are not bad.
Good selection, average pricing. I keep it on my radar just because it's domestic to me.
Never bought a ratrig printer but they have a lot of components, generally good quality. I got some leadscrews that are incredibly straight. Shipping was fast too.
A bit of everything at a very average quality. Price can be good, I bought some components in the past but I don't use them anymore.
Good filaments. BigTreeTech, LDO, Mellow vendor. Good quality, prices are okay. I ordered a belt once and they decided to cut it randomly (which is not nice). Very easy to reach also on Discord.
This was suggested by the community. I never bought from them.
Mostly LDO, BigTechTree and Phaetus vendor.
VzBot and Voron kits. Lot's of cool stuff, I bought a VzBot from them, can recommend.
This was suggested by the community. I never bought from them.
Like VM polymer goo, but cheaper.
Contact them via email, they can do custom beds. Not the fastest to reply.
Good quality but very expensive, also pretty long lead times. I bought a custom alu bed, 8mm thickness, it was pretty straight at the beginning but bent over time. Silicone heater and the printing surfaces are very good. They also sell Duet3d stuff.
High quality decent priced custom flexible steel plates. Great service, super fast.
I buy original hiwin rails from them. Very good quality and shipping is top notch to avoid bending. Not the cheapest but it's local to me so still worth it.
Profiles cutting service is decent. I also tried some of the linear rails they have and they are good quality. The 9mm carriage is nice (the one with tight tolerance) but rail is a bit too flexy (be sure to put it on a rigid support). Ballscrews and leadscrews are good but not great imho.
Motion systems, spindles, electronics, mostly for CNC. You may still find some components for 3d printers (ballscrews, couplings, ...)
Only place where I can find 15x15 and 10x10 profiles. Shipping is not the cheapest.
Quality is generally low. Buy extrusions only if you can cut them yourself because their cutting precision is very low. Don't buy screws, they are very low quality. Generally I don't recommend.
Stepper motors. It was okay few years ago, now I would suggest to go LDO instead.
I got ground ballscrews and variour linear rails. They do custom work, very good quality but not cheap.
Sometimes you can find good deals on original meanwell PSU (and various hardware).
Electronics. Not EU but taxes are paid directly at checkout. I generally buy switches, endstops and fans from them. Fast FedEx shipping.
One of the few places where you can buy shoulder bolts in EU.
Huge selection of screws and fasteners. Good quality fast service.
Never bought from them but it was recommended to me.
Good quality and price.
Useful for carbon fiber rods and tubes.
Useful for carbon fiber rods and tubes.
The extruder guys. Don't buy directly unless you really have to. Go to any of the many EU vendors, they generally have better pricing and often free shipping.
3D printer manufacturer. This is kinda off-topic but this is the only "low-cost" SLS printer I know of.
accu.co.uk Generic hardware
I bought very good quality shoulder bolts from them. Pretty expensive.
keenovo.store Bed heaters
Custom bed heaters. It takes about 30 days for a custom heater, but I've not been hit by import taxes.
Mellow on aliexpress 3D printing stuff
Very well known, generally high quality, but they are a bit hit-and-miss. They solve any problem you may have very quickly though. I've not been hit by import taxes.
robotdigg.com 3d printers and CNC stuff
Never bought from them but everybody recommend them. It's also the only place where you can buy Delta stuff.
n2ofactory.com Graphite build plates
I believe they come from China, haven't bought from them but it seems very interesting.
- Don't buy shoulder bolts from random aliexpress vendors. They are terrible, you are better off using M5 screws. You can find decent ones from Misumi, Accu and TME.
https://alchemy3d.de
https://replimat.eu
Could be worth adding
Former is partially run by me, latter is reputable in the Voron community
We also have a good reputation but I prefer you ask someone else than me to confirm 👍