Chapter 5 - In which I start to build the frame

With my recent delivery of components, I figured I could make a start on assembling the frame itself. I opened the wiki on the build page, and the visual instructions from Gary Hodgeson's site. I figured it would be best to have both sets open, so I could cross reference them if I got stuck with anything.

I picked up the first threaded rod, and got to work.

Some of the rods had burrs left on them from the saw. 

I had tried to find a big file to take them down with, but in the end resorted to a needle file. I filed off the burrs and rounded the edges a little to take off all the sharp edges.

I started the thread the bar clamps onto the rod, and they stuck. Having been built vertically to preserve their strength, the holes weren't entirely round, and had little nodules in them.

A little work with a half-round file soon sorted them out, and they slid down the rod smoothly.

I put the ends on, and set with length using a tape measure.

I started on the sides of the triangle,

And finished them off by adding the top piece.

I set the lengths of the sides with the tape measure, and tightened everything up. Once everything was tight, I checked the lengths again. One of the sides had moved by a millimetre or so, but was easily corrected.

With one side built, the other was done in a flash (ok, so maybe not a flash, but it was certainly quicker than the first one).

I started to build the front rods next. I found that the visual instructions had helpfully included the length of the rods when talking about the sides, but now only used a description. I got confused, and started to use the 440mm rods to build the front (they are labelled as "top / bottom" in the Prusa parts list, and the instructions said "top rod"). If I can work out how to do it, I'll submit a modification request along with anything else I discover.

I cross referenced the wiki build manual, and started again with the correct length rods.

One thing that the wiki mentions in this section is about spacing the front bearing. The nut and washer next to the Y axis motor carrier are there to space the bearing away from the motor. I checked the distance and alignment of my motor/gear in relation to the bearings. Whilst not perfectly aligned, I elected to keep the spacing nut in place, and make any adjustments by moving the gear along the motor shaft. The difference isn't that large, but if it becomes problematic I'll remove the spacing nut.

The spacing here is just rough, and the nuts are loose. Tightened up, the gear doesn't sit quite this far along the shaft.

I mounted the front to the sides - it's starting to come together!

The back rods were easier to assemble, as they are not connected to one another (and I knew which lengths to use this time...).

I fitted the back bars to the rest of the frame.

I finally used the top rods for their intended purpose, and mounted the Z axis motor holders. I adjusted the frame using the tape measure, and tightened up all the nuts. I also fitted the smooth rods, and the lower bar for the z axis ends. I have the smooth rods just about centred and the spacing set, but had difficulty with getting the bottom bar into the correct position. I think it is right, but will need more checking and adjustment when I come to work on the z axis parts.

And there I have had to stop, as the next part requires things that I don't yet have - namely glue and M3 screws. Also the British Grand Prix was just starting.

Next up: buying more stuff, and drilling acrylic.