The book said that it can only use 1/6 to 1/4 electrodes.

I would check your connections on the new machine on the backside of the terminals make sure they're all tight nothings loose

One thing you could try is to warm the steel up a little bit usually with the 7018 1/8 I run anywhere between 90-120 amps or another thing you can try is the 7018–1 Rod

I like to use the gold Lens shade #12 for all my welding it gives you more real life like Color