First Prints

Well, I decided that in order to rule out the torque issue, I decided to buy a Greg’s Wade reloaded extruder for Prusa i3 and mount this as a direct drive extruder.

The extruder was £22.99 with free shipping from ebay and came with all the required hardware for assembly.

I assembled the extruder by following the instructions on phenom networks, who have a very good assembly guide with plenty of pictures.

Some of the nuts were a bit loose, others required a soldering iron to seat them in their sockets, and the holes for attaching to the Prusa X carriage were about 5mm out. As a result I had to re-drill one of the sets of holes closer to the hot end so it would attach to the carriage correctly.

I decided to use some M3 nuts as the spacers for the motor as these were unlikely to fall off , unlike 3 stacks of 3 or 4 washers, and make my life difficult when I was attaching the motor to the main assembly.
I then needed to re-calibrate the extruder – this extruder ended up with a steps per mm setting of 826 to extrude 100mm when I requested 10 x 10mm within the GUI.
Some more playing with the slic3r settings and I am finally extruding plastic reasonably well, however it still won’t stick to the heated bed.

I re-level the bed and play about with the start height and eventually I start to persuade the PLA to stick to the bed.

Unfortunately now it seems to get half way through the first layer and then tears up the layer as it passes over high spots that have not stuck down or extruded well.

The other issue is that around the time that the first layer is nearly complete, the hobbed bolt in the extruded grinds its way through the filament and no more filament is extruded.

I decide to dismantle the hot end again and check the diameters of the various parts.

Even though I ordered a 1.75mm extruder, it would seem that I was actually sent one for 3mm filament, and the molten filament is backing up through the PTFE liner and eventually becomes too stiff to push at which point the extruder grinds through the filament and stops being any use.

I decided to drill out the PTFE liner from 3mm to 4mm and sleeve it further on the inside with a short length of 4mm OD, 2mm ID PTFE tubing that I have been using on the bowden extruder.

I decide to leave the melt pot as it is for now, even though it is a little to large, and re-assemble and try again.

Finally I manage a decent print that sticks to the heated bed and continues all the way to completion.

The only issue being that 2/3 of the way through the print the host software appeared to be doing a lot of resend activity and the printer nearly ground to a halt, other than that, a fairly uneventful first print.

Following on from the success of printing the front side of the Pirates of the Caribbean Coin, I decided to print the back side as well.

It is still not 100% perfect, but for now I am happy, there are virtually no “strings” showing on the print and both sides printed without issue.

So just over 2 years from my opening post in this blog, I finally have a working printer.

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