Sunday, 29 January 2017

Core XY update 2.5

Just a quick update

Its alive!  Well X and Y are doing the coreXY thing

I had real issue getting the X axis to move as nicely as I wanted. It would move but was stiff. I wanted the axis to be 'loose'. ie without belts if the printer was on its side I expected the head to move down towards gravity, same as Y does.  After a lot of mucking about I worked out that the top right (in the above image) mount of the X carriage needed a shim. Two pieces of paper where enough to bring it into alignment.

The next hurdle is the heated bed. Its on a 3mm piece of aluminum,  so the instant you try and solder it all the heat is drawn away.


Saturday, 14 January 2017

Core XY update 2

Many M3's have been acquired and installed

Y axis is in place, the smooth rods from china where over length, +2mm, and had to be trimmed to size. This took some to time to trim, they are hardened steel.

Still no X axis rods, has been ordered and is coming from Australia.

I'm using a geared extruder as I intend to use 3mm, so I had to design a new extruder mount to match my extruder mount size requirements. I did my best to make it the same style as the original mount. Designed in Openscad, source is provided.

The Z axis is complete. I had to print a new Z axis nut mount as the standard one didn’t fit my Z nut. But the designer has nicely provided a few alternatives

The Z stepper mount internal hole was a little small for my stepper, but nothing a little filing couldn’t fix.

I have also hooked up a RAMPS and the Z axis moves! Zero wobble.

I have attached the Z lead screw support plastics at the top, just to give the lead screw some protection from potential damage and fingers. I may add a cap over the top of this at some stage.

I have assembled everything else I have at this time.

NB anyone else who wants to use m3 cap head screw (which I am quite fond of)
There are 6 places you can not uses these as the cap head is to tall.

The hotend mount to X carriage screws are under the fan on one side and the fan duct on the other, ie they need to be flush and cap head screws stick out.
Similarly the dual bushing to X axis requires screws with shorter head for 2 of the 6 screws as the hot end mount sits flush over them.
The belt did not come like this, it came loosely looped and tied with a bit of string. It annoyed me so I wound it up nicely.

I had to reprint my dual bushing holders as there was no way the bushing was going to fit. I reprinted them with a 0.9 extrusion multiplier as suggested in Tech2C's videos. This was a close fit, but I still couldn’t get them in by hand. I used a wood vice (wooden jaws) and carefully squeezed the bearings into place. This worked really well.

Now the long wait for the remaining parts...

Saturday, 7 January 2017

Core XY update

I have assembled what I can with what has currently arrived

The Z axis is in place and moving freely, even though It has no lm8uu clamps yet.
I haven’t cut down my Z smooth rods from the ordered 380mm to 340mm. It sticks out the top I don't mind that. 

The Y axis is in place. The rods from china where fractionally over 300 and had to be trimmed. This was time consuming, being hardened steel. 

Putting this together I am looking at the Y axis, if I was to lower the top X and Y tslot and put the Y axis on top, this would increase the Z axis depth quite a bit, for the same parts. I may try this after its done. Or maybe I'm missing something that not obvious yet.

Next I need to reprint my Dual bushing holders as my bushings will not fit.
I've found that most holes are too small and need drilled, luckily with 3 perimeters, this is not an issue. Some of the m3 nut traps are very tight and needed a bit of work to get them to size.   

I am still waiting on X axis rods, and a bunch of M3 screws and belts + pullies.
Lucky tomorrow most places are at least partially open after xmas, so I should be able to get the remaining m3 hardware.

Friday, 6 January 2017

Core XY

I decided it was time to try something a little different a core XY machine.

I've gone for a HyperCube 3D Printer from Tech2C

I decided to start this just before x-mas, a terrible time to try and get anything shipped, consequently I am still waiting for many parts to arrive.

This is more or less what has arrived thus far. 

And I've printed most of the plastics, and assembled what I could with the m3 hardware I already had.

Today, finally, the m5 bolts arrived

I have assembled the basic frame, this is still loose, needs tightened. 

Some of you may have noticed the aluminium corner brackets I am using on the XY plane are different from those listed. I had these left over from a previous project.

The listed brackets are the right hand ones.  As you can see they are quite a lot smaller than the ones that I already had. They are also 20mm wide. A fair bit more substantial than the new ones.  I don’t think this will cause any issues, but obviously cant be used on the XZ and YZ plane as other parts are butted up against them.  

I've also used a bunch of standard tslot nuts, as they are more substantial than the ones listed. These of course do need to be put in place prior to the ends being closed off. You can't add them latter like the new nuts.