Hey guys i am new to 3d printing, and lulzbot printer 5, i would like to print in little more detail, where can i get the .35 mm adapter? or i need the whole new printer head?
All you need is a new nozzle, they’re about $7.
You can get them from these folks:
I just ordered two .5 mm nozzles because I just had a bad clog with my .35 nozzle (first in a year) and the bigger nozzle opening is said to reduce clogging. And to cut back-pressure as well.
If you change the nozzle size you’ll need to change that info in your slicer software to match it, but that’s it.
Be sure to follow the instructions on the Lulzbot site (or in posts here) about how to change the nozzle – it has to be done “hot” and you need two wrenches to keep the rest of the extruder head from twisting.
You can buy a .35 nozzle from Makerfarm.
Or a replacement hotend with the .35mm nozzle from Amazon or Lulzbot.
do they have video anywhere? About this so I can watch it before I do it…?
Also every time I do change setting in cura from lulzbot it ask to load some firmware?? Do you have to do that every time?
You do not need to do anything with the firmware for a nozzle change. You need to change the nozzle size and possibly the initial layer thickness on the advance tab.
Change the shell thickness to a multiple of the nozzle size (1.05 is 3 shells of .35mm), Bottom/top thickness on the basic tab to something smaller than the nozzle size, layer height to something less than .28.
I don’t know of any videos of changing the nozzle. What I do is first bring the nozzle up to print temp then let it cool to about 2/3rds the full temp and pull the filament out by hand. Then heat back up to print temp. Using two wrenches (I use a crescent wrench and an 8mm wrench)
use the larger one on the heater block to prevent it from turning as you use the 8mm to unscrew the nozzle tip. Then I let the temp drop down to 2/3 and push the rest of the plastic out with either fresh filament or an allen wrench. Install the new nozzle with the 8mm wrench and again holding the heater block so it will not turn. Make it snug, but do not over tighten or you could damage the nozzle or block.
Insert new fiber and heat up to temp and run a couple of hundred mm of filament through. Make sure the filament comes out nice and straight. If it starts to curl, you may need to remove and clean out the nozzle.
Scott
You do need to be careful when changing the nozzle. (There really is a reason why the folks at Lulzbot do not recommend changing nozzles. 
)
There is a very fine line between tightening the nozzle enough to prevent leaking and over tightening. Since the hearter block is made of aluminum, when you over tighten, you actually start to pull the threads out of the heater block (i.e. strip the heater block threads.) Lulzbot has informed me that they tighten the nozzles to specific torque specifications. I’m just too cheap to purchase the correct torque wrench. 
I have worked on aluminum engine parts for years so I know to be careful. Even so, I have managed to strip the threads on one heater block. As a result, I built a second tool head for my 0.35 nozzle so that I wasn’t changing nozzles as often.
Thank you guys, but when I change the setting from .5 to .35 in the program that won’t update other numbers for me ?
Unfortunately, no. However, I just recalled that there is a much easier way. You can download the Lulzbot profiles for the .35 nozzle. This will have all the changes already set. If you have made any modifications from the default .5 nozzle profile, and want to use those modifications with the new nozzle, you would have to make the modifications again after loading the .35 profiles.
Scott
And the reason why it’s like that is because there is no good manual for the hexagon. If you read the Lulzbot manuals, you could think you have to tighten the nozzle to the heater block to prevent leakage. That’ the important wrong thing, where you have a high chance to strip the threads!
I recomend to read the howtos for the e3d v6 nozzle, their internals are nearly the same so the guides are valid for hexagon also.
Or read my instructions here: Can't stop Hexagon hotend leakage Short summary: You dont need a torque tool, you don’t even need force. If you don’t apply force, there is no risk of stripping threads. Problems solved 
The trick is to screw the nozzle against the heat brake, not the nozzle against the heater block!