74HC595N control solenoid - arduino startup problem

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4

I don't see any decoupling on the 595 chips.
They need 100n ceramic caps from VCC to ground, close to each chip.

Made something similar a while ago, and I wrote a HIGH to the three shift register pins BEFORE setting them to OUTPUT with pinMode.
Leo..

  digitalWrite(latchPin, HIGH);
  digitalWrite(dataPin, HIGH);
  digitalWrite(clockPin, HIGH);
  pinMode(latchPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  pinMode(clockPin, OUTPUT);

What is the value of the base resistor.