Possible find as to extrruding issues

In the past few months I have seen with the user of the ROBOs that there seems to be an increase in extrusion issues that are not getting resolved and Ialso noticed a high percentage of them were using the E3D hot end. Well I just want to bring up something that was brought to my attention today and I am not sure if there could be a connection or not. It was brought to me by a new user name Fred Muldal who is quite experience in CNC machining and build cars from the ground up. He noticed that on the top section of the cooling tower there is a conical shape cut into the top of the part to serve as a guide for the filament to enter the main tube at the bottom of this conical cutout is where the main tube starts
what he noticed was that on his he coudl see the base of the conical cut and the just slightly off set form that base was the where the main tube started he also noticed that there was a slight burr at that point as well. I got my spare set up and looked at mine and found it was almost identical to his under magnification I could see the bottom of the conical cut then just a bit offset from there the main tube starts and I too had a burr in almost the same spot he did
Her eis a pic of the magnified view showing all of this

The crescent moon shape is the bottom of the conical cur and the main hole is just off center from that base and the burr you see on the left edge seem to be right where the edges of that conical base cut and the main hole converge, there is also a small burr on the bottom section where the heat break joins in. The thought was this maybe the prcess changed a bit at the source when demand went up I remember there being a delay in getting them for a time and even though this is in the cooled section of the filament path you all know as well as I that any filament obstructions tend not to be to nice.

This could be the cause of some of the cases where people were having a hard time getting the E3d to load this is a spare setup for me so I plan to actually file it smooth a bit but won't be able to test it.
Fred told me that he simply considers this bad CNC work and it may be worth looking into by others, maybe we can see how wide spread this little thing is.

It didn;t really inhibit the filament when it was fed through that I could tell but then the filament was not going through different changes as it does when it is used for printing.

Please comment and check yours out if you can I found it interesting that two were checked and two were found to have this issue let us all know what you find out with yours.

 

Remember I have been talking about the non bowden style just to make that clear.


I just did verify something I have a drill bit that fits loosely in the main hole when I put it in my drill and then put it in the main filament hole of the E3d on the bowden style it starts to spins as expected and teh rotation of the entire cooling tower is very symetrical indicating the main hole is on the centerline of the cooling tower. This is not the case on the non bowden style there is a definite wobble, asmall but noticable and that indicates that hole is NOT on the centerline of the cooling tower.

Again not sure if this has a bearing on things or not but it is an inconsistancy!!!!


On a good note.... I have no more burr. Yeah!