All metal throat

demillertime

I wanted to share my troubles replacing the ptfe lined throat and hot end. I also replaced the Bowden gear with a hardened steel version as well so I can reach higher temps for nylon, polycarbonate and carbon fiber...

In the images below you can see the longer throat with the plastic lining and the shorter one with the all metal construction. Yes, I did damage it good trying to remove the old. I am never going back so it doesn’t bother me...

Not going to lie it was a giant pain in the arse. Turns out the e3d nozzle has an m7.1 thread in the heat sink where Jg has an m6x1 still. So I had to drill and tap a new hole for that. No issue. 

Then the wire pulled off from the heat sink fan which is not a very easy solder job, let me tell you. Then I had trouble getting the gt belts tight in the block but finally got it.

you might also notice the length is much different. My nozzle is now much further from the bed but I do have automatic bed leveling so I just had to adjust my -z settings, and by adjust I mean double it from -2 to -4...

Now all I need is to remove the 250 Celsius limit in marlin. Although I’ve noticed simplify 3d overrides this limit if you set it higher it would still be nice to preheat bed and extruder at same times.

Samuel Pinches

Nice job!!! Looks like you’ve done this properly  

now that you’ve got an all metal hotend it is easy to increase the max temp limit - this is in configuration.h , you can just raise the limit and reflash.

demillertime

Yep luckily I work at a manufacturing facility so I have free reign to any mills or tools I need. My first print has stopped extruding on the last few layers, not sure if the filament is getting hung up somewhere in the throat or if the gear I’ve got isn’t gripping as well...

Also ordered a larger blower fan to upgrade, the soldered wire probably won’t last forever....

demillertime

The throat continually jams and won’t extrude. The Bowden stepper does the typical stick and click and nothing comes out the nozzle unless I manually push material through by hand. Any ideas? If not ill have to install the aero when I get it.

Samuel Pinches

Maybe turn up the stepper driver current slightly for the E axis? It’s hard to get metal to be as low friction as PTFE tubing, and that’s why the E3D genuine ones are favoured - but even then it doesn’t sound like it’s easy. Also maybe try turning off retractions to see if that helps.

demillertime

Is the max temp adjustment the line #define HEATER_0_MAXTEMP? Also do I adjust driver current on the driver board or from software?

demillertime

Nvm about stepper current. Found the info on wiki.

Samuel Pinches

Yes, that line in configuration.h is where the max temp is set in the marlin firmware.

The important detail regarding the TMC2XXX is that even if you have software control setup, you still are limited by the current set by the potentiometer - so that may need to be turned up, or it may become limiting.

Solo

Did you solve the issue ?, since I am doing the same for mine.

Der_Muck

I recommend to use the micro swiss mk8 throat. With that throat you dont have to change the thread.
https://store.micro-swiss.com/collections/spare-parts/products/thermal-tube-upgrade-for-makerbot-replicator-1-2

compman2

Der_Muck
Have you installed the micro swiss throat on your printer?   I would like to do that on my A5 so I can print at higher temperatures.  Are there any tips and tricks you can pass along about this swap.

Der_Muck

Yeah, retractions are totaly different to the PTFE throat. MS say max. 3mm but for some filaments, I have more and its ok. (wood and TPU)
Keep in mind that the max. print temp. is 250-255 on the A5 so if you want to be most times in that range, think about a change to the E3D high temp. variant with the PT100.

In generell, the change is like a change to a other PTFE throat, there will be nothing special.