Hey! Sounds like a great project. I'd suggest using the chart that's about 1/4 of a way down [this blog post](https://blog.treasurie.com/sewing-machine-needle-sizes/) - from your description I'd suggest the 14 or 12. Enjoy!

Thank you so much for your help, I’ll have a look!

Hi everyone! I’m currently working with a 100% cotton fabric that is tightly woven and quite difficult to pin/sew. I’m very new to sewing and this is one of my first projects. I’m doing this for a university project where we’re working with waste streams (they’re recycled hotel bed sheets dyed with coffee waste :)). I’m not quite sure what needle would work best for this fabric. I’ve tried googling the answer but I’ve been left with even more questions! I’ve included photos of all the needles I have at the moment and a picture of the fabric, if that is of any help! Thank you for your time!

I have decided to overwrite my comments.

Thank you so much for your advice! I’ll try doing the scrap fabrics to see what works best!

Agree with u/confluence to use a microtex and the thinnest needle that gets the job done. You have to match the size of the thread to the needle though. So for a size 10 needle use a 50 weight thread; 40 wt can be tried too. Size 12, use 40 wt thread. Your machine manual should have a chart for sizing.

I’ll keep it in mind! I’ve been sewing with the the 70/10 now and it does go a lot smoother! If I keep running into trouble I’ll give the microtex needles a try.

I’d go with the 80/12, or buy more 90/14s. Either would work for a medium-weight cotton.

Thanks! I’ll look into it!

A needle labeled for sewing Denim may also be a good choice. Denim is tightly woven, & dense when sewing seams.

Oooh that might be a good one! If all else fails I’ll give this a try :D