Few question regarding 3D printing safety  

Re: Few question regarding 3D printing safety

1 - As a part of the lack build you should move the PSU outside the enclosure this is included in the instructions and a part is supplied to attack it to a leg on the table as well as cable pass throughs to allow you to connect the supply up. The cables and other electronics will be fine with an unheated enclosure.

2 - Runaway temp is enabled which will stop heating if the thermistor is not giving a reading. Max temp is enabled at 310°C.

3. Never had an issue with mine and E3D do supply them for use with their hotend so I can't see it being a concern. The biggest risk with them is they can get damaged/fall off mid print and cause you a print problem or failure.

If you're planning to stick to PLA/PETG these are both pretty safe filaments and don't cause smells or large amounts of particulates, ABS is a different matter so I would investigate further if you change your mind.

I would advise getting a supply of IPA, acetone and glass cleaner to clean the print bed. IPA for PLA, glass cleaner for PETG as IPA makes it still too well to the bed and acetone for a complete clean if you are having issues with prints not sticking.

Overall the MK3 is one of the safest off the shelf printers there are a few quality of liffe mods that could be worth printing such as the belt tensioners but no safety minded mods are needed.

Re: Few question regarding 3D printing safety

Thank you a lot for the reply, well I assembled my own MK3 from the kit, so far it is working fine, I did few prints for around 60 hours, longest was around 6 hours single print, had no issues so far 🙂 "other than going crazy adjust 1st layer for PETG then hardened steel nozzle, then getting back to brass.

For question 1, you mean the electronics and the cables will be save in a heated enclosure for long amount of hours? " of course will take the power supply out"

Re: Few question regarding 3D printing safety

1- I am thinking to build the LACK enclosure https://www.prusaprinters.org/cheap-simple-3d-printer-enclosure/ however so far, I have no plans printing ABS, just PLA and PET-G for now, would the enclosure causes the electronics and wires to overheat?

It's entirely up to you, but unless there are overriding environmental issues, an enclosure isn't really necessary for those two plastics.

3- I am getting the E3D pro silicon socket to cover my heat block and most of the nozzle to prevent any filament from sticking, I noticed that the V6 pro socket silicon covers a small black venting " I assume " hole in the heat block and covers most of the nozzle as well are those safe to use and won't cause any damaged to the hot end or causes fire?

Again, it's up to you, but some of us prefer the improved version https://e3d-online.com/v6-sock-3pack
They're not on clearance, but I've read here that they can have problems with filament accumulating on the nozzle under the sock. Possible other issues.

Since this is the "improved" version, I would "assume" E3D thought about fire hazards, and included design modifications & warnings (but I could be wrong).