Need help keeping a rigid mechanism in a 60ºC(140ºF) Incubator

[stopfortheklopp]

I've built an incubator with an electrode at the center with the purpose of cell culture, screwing a block with copper tape at each of the ends of the electrode to pass current, but given the fact I need the incubator to have a temperature of 60ºC the nuts and bolts come flying out when I reach that temperature. How would you prevent it? adding weight to the blocks? changing the types of bolts? or what would you change in the design? Here is an very rough schematic of what I'm talking about. https://i.imgur.com/HkY7kSS.png

Any help is greatly appreciated

 

[(*steve*)]

Clip the wings of the nuts and bolts. They should stop flying.

I don't understand your problem and I wonder if you need two threads. Isn't this similar to your other thread?

 

[duke37]

You could screw up the bolts till they reach the yield point. Alternatively include a Belleville washer to maintain the force as the dimensions change. Use locking nuts to stop them spinning.