Neodymium/rare earth magnet grade advice please

[Terrapin88]

Hi guys and gals.

I want to use magnets instead of screws for the box lids. I've been all over hell researching and trying to decide what grade or strength to get. I am going to epoxy 1/4" magnet into the lids and use set screws on the boxes. I need 50-100 so $$ is a concern, otherwise I'd just get the N52's and be done with it.

My choices online are N42, N48 and N52. Not sure if I need to go with the 1/16 or 1/8 thick discs. Also not sure if I can get away with using set screws (steel, not SS) in the box or should I use 1/8 x 1/4 cylinder magnets instead of the screws. I've never played with Neo magnets that small so I have no frame of reference as to their strength when it comes to holding a lid on a box.

Can anyone that has used these 3 grades give me some advice please?

 

[Hill]

I've tried the n-52s they're pretty strong, they should work either way you want to go.

I got them for a good price online at K and J magnetics .42 cents each. I went for the 3/16" x 1/16". They're plenty strong.

I use 4 of them in 2 pairs to keep the doors on my wooden mods.

 

[Terrapin88]

Thanks Hill. Have you tried any of the lesser grades for comparison?

I have K&J bookmarked as a last resort, but I'd like to try and do better on the cost if I can.

Great Ben Franklin quote BTW

 

[asdaq]

Since you want quite a quantity of these, I would check home depot/ Lowe's also. They carry standard cabinetry magnets that are just about what you are looking for. Basically the larger the magnet, the more pulling force, and n42 is going to be OK. The big box stores will be better on price. K&j are great for specific needs but are rather pricy especially with shipping. You might check eBay as well. I've bought from all three places and each has their benefit.

 

[Rickajho]

I can't give you any advice on the grading but I've bought low priced Neo's from DealExtreme and those suckers have great pull. They will have them priced at several different quantities from 10 to 100. Huge assortment of magnets.

 

[Terrapin88]

Thanks for the replies guys.

 

[Terrapin88]

I ended up with N48 grade. I got 50 1/8 x 1/4 cylinders and 50 6mm x 3mm discs for $14 shipped via Amazon.