mastermats

Hello, I started to run my own tekkit server a few weeks ago. First it runed fine but know everyone but me hava lag. I run my server on my local desktop with 12G ram with Hamachi. I have a few plugins instald: Essentials PermissionsEX LWC Worldedit Voxelsniper and AutoSave And we have a few quarry's but loads of machines. Do anyone of you know how to fix this lag? or witch machines I do not want to use or anything esle???