AO-100 Mod - Print Height Increase and Easier Front Access

First, tip of the hat to Seesoe who made me realize we could significantly increase the printing height on the AO-100/101 by making a few new printed parts and keeping everything else stock. Quite an easy mod for someone like me with limited tinkering experience.

I was set to making his upgrade, but after a few months’ use with my AO-100 I decided I wanted some more changes.

  • I wish the extruder was more accessible. The two top horizontal aluminum extrusions get in the way.
  • The front slanted frame is in the way when I want to take pictures or record video.
  • Only new printer parts should be necessary, and possibly some more M5 screws and t-slot nuts, everything else should remain stock.
  • Ideally keep the X and Y axes as they are, basically I do not want to take the whole printer apart (otherwise I could make a mini-TAZ out of it)
  • Make non-destructive changes, i.e. no t-solt cutting so I can revert back to original configuration if it does not work as planned.

I like the few notable recent RepRap designs like the Mendel90, the Prusa i3 and the MendelMax 2.0 because the build area is totally accessible from the front and the sides, and the extruder is in front of the vertical frame. The TAZ has pretty good access too.

With that in mind I’ve made a preliminary design. (sorry for the animated gifs - thought it would be useful but three in a row is a little annoying… :unamused:

I’ll admit I’m a little concerned with the rigidity of the upper smooth rod attachments. I don’t know if they will flex. From the center of the smooth rods to the front of the vertical posts there is 85mm.

When I’m farther along in the design I will upload the FreeCAD, STEP and STL files to GitHub.

Suggestions are welcome.



I would also be VERY worried about the Z smooth rods being able to wobble…mostly in the X direction. It is only the stiffness of the printed part that will restrict that motion.

can you move the Vertical extruded pieces closer to the rods, or perhaps on the opposite side? (user side). i know you will lose some of the accessibility, but the front will be kind of like the TAZ then.

remember, the whole point of the vertical aluminum structure is to keep those smooth rods stiff. the closer you can get the aluminum to the end of the smooth rod, the stiffer it will be. (since aluminum is much more stiff than ABS)


Thanks for your input.

Putting the vertical t-slot at the front won’t give me much gain, they will still be distanced 65mm from the smooth rods. Otherwise the X-carriage would hit them.

I think I need to put the vertical extrusions outside of the frame for it to work. Putting them right in line with the smooth rods would allow me to put them very close to the smooth rods, but they would be outside the base by quite a good amount.

It looks like I cannot do this with the extrusion sizes I have, I would need to source new longer extrusions.

I will think about it further.

Something like this…

Could you angle the currently vertical extrusion pieces forward some, so they are maybe 70 to 80 degrees. This would put the top connection point closer to the smooth rod ends but maybe still allow for your increased travel.

I can’t, the vertical extrusion pieces are distanced 85mm from the center (were the smooth rods are aligned) because otherwise the rear cooling fan will hit them (look a the third gif in my original post). If I put the cooling fan at the front, I can bring the vertical extrusions to 65mm from center, this is still not enough, plus this will hide the hot end.

What’s a pity is the frame would only need to be 10mm wider each side (20mm total). Then I would not have this problem.

Simply put:

  • the X carriage is too deep
  • the frame needs to be wider so the x carriage does not collide with the vertical extrusions

I guess my choice is either make Seesoe’s print increase mod and live with the lack of accessibility of the frame design, or make a completely new frame with sourced extrusions and salvage motors and electronics. I would probably need to go with a vertical x carriage like the TAZ rather than an horizontal one.

if you could just add some metal triangulation pieces to the plastic parts you have designed now, it would help. I notice there is one piece of aluminum left over…cut it in half and use it. Or use threaded rod or something.

Yeah, I thought of that… But that would be an ugly hack… :wink:

I’m more and more thinking I should do this properly. Build the whole frame, then only when it’s complete, transfer the hardware and electronics to it.