How Would You Upgrade An Old Ox CNC Build Into A Serious Machine?

[Kitwn]

I said it in other thread : I buy from these guys https://es.aliexpress.com/store/822038 12 and 15 size. Have not bought from them 20 size , but their rails are very good quality and price. Custom size also, contact them. make sure to buy the long carriages.

Boyan,
I notice that both BST and your recommended supplier Hong Yi sell both the 'miniature' MGN15 size rails and the larger HGR15 (same size as Hi-Win). The overall height from the base of the rail to the top of the carriage is only 16mm for the miniature compared to 28 for the standard size. Strangely enough the larger size works out slightly cheaper from Hong Yi for the 400mm set I'm looking at for my planned Z-axis upgrade. 15mm seems to be the largest size available in the miniature range and the smallest in the standard sizes so this is the only size where the confusion might occur.

I'd advise anyone looking at 15mm rails to check exactly what you're buying. No doubt the miniature size has practical advantages for some projects but it is not as robust as the standard size for heavy load applications. Those initials make all the difference!