Frage Some thoughts after assembling my 840

1) Wire length is a bit strange.

Some wires are just a bit short (I had to pull them with some force), and others were too long (the X-Axis wires are double length but that extra length is not used at all).

The kill-switch wires were really tight.

The smaller tube was very annoying. I had to pull the wires really hard at some point that I feared they would break.

2) The base board didn't fit so I had to sand it several times (the borders).

3) Connecting the wires was the last step and it was a hell. I had to sit on the floor and blindly insert all the wires. I hope it works. Haven't tried it yet. It would help if the board was placed looking to the ceiling and not to the floor.

4) Had to sand the work holders because the paint at the endings was thick enough to not let them move.

After all, these were minor problems, and once the assembly was done the machine looked really great.

I will agree with jvalencia and more for the 4 section i have sand the work holders to because when i tight The work holders they stuck, and i must sand the paint to work.

Had a similar problem with point 2) when assembling my 420. I found that it was due to a number of "pinch" points along the length of the aluminium extrusion on one side. Pinch points were at start and end of the track and another one in the middle where there was a slight "dink". Two minutes of light filing sorted it out and now base boards slide in well.

I haven't finished assembly yet and I have also found that the wires were too tight on the XZ module along with a few other minor issues. Checking on this forum (before registration) helped identify likely causes including washer issues.

I believe I have got the hang of the pre-tensioning which is very random and fiddly I must say. Nevertheless, a showstopper at the moment is that I cannot get the XZ module to run freely on the X axis track unless the FIXED track rollers are basically loose and the pre-tensionable rollers are NOT pre-tensioned.

So my problem is not enough play, rather than excessive play in the rollers. I suspect that I will have to remove some of the powder coating on the mounting holes; I have already done this on the adjustable rollers because the brass fixing nuts wouldn't move freely. Somewhat frustrating as others have expressed.

Other than cost reasons, I cannot understand why the orange end plates do not have a rebate milled into them to accept the aluminium track extrusions. This would align them precisely and avoid having to fiddle around ensuring that there is a consistent 1 mm gap at the edge!

Also, Rory of StoneyCNC has been very helpful with prompt responses to my questions.

Doug