Colorfabb HT

We are trying to run some parts using Colorfabb HT on our Taz 5. We are using the Lulzbot print profile . It puts down a good base layer and then starts to miss areas on the subsequent layers. Anyone have any experience with this filament.

This could be caused by a few things, but most likely it will be heat creep related. Before anything else make sure that the microblower on your toolhead is constantly running and directed at the heatsink on your toolhead, if something caused this to jam, get moved, or a wire on it broke that will almost certainly be the root of your issue.
Then move on to checking the z-offset, if this is to low it can cause filament to back up in the hotend and this can lead to clogging and poor extrusion in subsequent layers.

If that is okay check is the tension on your idler. If this is to tight over time it can grind away the filament leading to poor extrusion in later layers. We recommend ~5mm between the washers on your idler when filament is loaded and idler is in latched in place and fully compressed.
If none of those help try dropping the print temp by 5 degrees or so, sometimes if the filament gets to hot in the hotend the hobbed bolt will just grind through it and cause poor extrusion. The temperature set in Cura’s material profiles is a good base but filaments of the same type and brand like slight differences based on the color being used.

Perhaps if you could post some photos of the failed prints it would be a little easier to pinpoint the problem. I’ve been printing with HT since it was released and it can be a challenge to get it dialed in.

I do have to run the nozzle hot… 270° C to get a good flow on the Titan Aero. Also retraction is tricky. In S3D I have the Retraction Distance at 1.20mm, the Vertical Lift at 0.20mm, Retraction Speed at 400mm/min, and Coast 0.20mm. Of course those setting will be different on the Hexagon Hotend.

We seem to have got our print quality were we like it. We installed an Aerostruder head and the heat creep problem is gone. The HT actually prints very nice. However… We upgraded to the latest software and are have problems with it. No matter what we do the beginning of the print is missing. Imagine printing a small chair but the print does not start till partway up the leg. Any ideas? Can we use the Aerostuder with the old software?

Are you trying to print files from G-Code made before you upgraded to the newest Cura 2.6.69? Luzbot has a warning about changes in the new version that makes models sliced in earlier version incompatible and they need to be imported and re-sliced in the new version to work.

This is from the Lulzbot site:

"Current Version: 2.6.69 [Release Notes]

Cura LulzBot Edition version 2.6.69 contains firmware standardized for use with all LulzBot Mini 3D Printers, and contains important bug fixes. However, once your firmware has been updated to, GCode files sliced with earlier versions of Cura LE will no longer be compatible and will have to be re-sliced using the latest version of Cura LE.

We recommend using the latest firmware included within Cura LulzBot Edition to maximize long-term compatibility. Users that need to use existing GCode files can restore compatible firmware ( or below) through Legacy Cura LulzBot Edition v21.08."