I have purchased an AM8 kit off of eBay from RatRig (https://www.ratrig.com) in Portugal as there does not appear too many alternatives in Europe let alone the UK. This was shipped quickly and arrived in less than a week, a month before Brexit so no customs/borders issues then. I could have purchased the extrusion, screws and captive nuts separately in the UK but the total cost worked out significantly higher.
The RatRig kit has the 7 basic extrusions (using V Slot 2040 tapped with 5mm holes) cut to length and sufficient nuts bolts and brackets to assemble the standard angle bracketed AM8 frame.
However I thought that the drill-through design of futureismaker looked stronger than just using the angle bracket joints provided in the RatRig kit so I decided to make those modifications first. Crosslink has a couple of good Videos on how to do the AM8 Conversion and they can be viewed here:
Crosslink's Video Part One: https://www.youtube.com/watch?v=MSE7Gt9jKu8
Crosslink's Video Part Two: https://www.youtube.com/watch?v=010-FF42ACU
The AM8 conversions are documented here
Pheneeny's original AM8 Conversion: https://www.thingiverse.com/thing:2263216
Quick Link to the build guide by Pheneeny is here https://cdn.thingiverse.com/assets/18/96/c9/fc/38/Build_Guide.pdf
Futureismaker's AM8 Drill Version printed parts are here https://www.thingiverse.com/thing:3721764
The Y Belt Upgrade/Conversion is documented here
I have used a modified version of DruckiMCDruck's Y Belt Upgrade https://www.thingiverse.com/thing:2970681 to use a toothed GT2 pulley with integral bearing that I had already purchased to upgrade the original A8's X and Y axis idler pulleys. But to be honest it would have been a lot simpler and quicker to have just used Pheneeny's first time out.
Warning! If you are going to be making the AM8 Drill Version - Make sure you are looking at the right image before starting to drill ! The AM8 - horizontal Y Belt Upgrade shows the front and back bars as being connected inside the side rails and not to the end of the side rails as per the AM8 Drill Version which I am building. So I now have some spare holes on some of the bars!
Whilst the above all provide STL's for the printed parts the details of the slicing and the printing of them is not that clear. Specifically what filament materials are suitable, the depth of layers and infill density. I have to assume that the best orientation for strength has been chosen in the provided STL's as I certainly would not have chosen to print the Z motor holders in the that orientation as a simple rotation would completely remove the need for supports.
Fortunately none of the printed parts are near to the hot end or hot bed; and at 60mm/s none of my motors have ever exceeded 35°C. So from a temperature perspective PLA or PLA+ (with a glass temperature as low as 54°C) would still be safe for the initial build.
For now I have printed the Z Motor Mounts using normal PLA at 195°C/55°C with 0.3" layers, 4 line borders, and at 20% infill this took 3 hours at 60mm/s on the A8. I also printed the Y-Rod_Holders using a fresh reel of no name PLA+ (for increased strength) at a reduced layer height of 0.25" and 20% Infill. This was the first time that I had used this filament type, and the prints exhibited marked corner turn up (elephant feet). I have since bought some eSun PLA+ that seems to be far less susceptible. However I eventually discarded the PLA+ Rod Holders in favour of the Aluminium Rod Clamps that came with my extended Y Rods.
The changes that I have made to the thingiverse designs are:
The two Z Axis top supports contain a holder for a 8x22mm anti-wobble bearing which I am totally against using as they can cuase binding on teh threaded lead screws. So these can be simplified. These holders are also fixed - so I have split them into 2 parts to allow for manual adjustment to get them true.
The Z Axis Motor mounts were printed rotated to remove the need for supports
I have ordered some kitchen cupboard parts to strengthen the frame.
Some Hafele corner gussets from eBay these steel parts to hold the base frame square.
A pair of 192mm (7.5") straight metal braces (HAFELE DOOR PANEL CONNECTING PLATES) on each of the verticals. These needed a 3mm kink hammered into them at the lower end to get around the Z_Motor_Brackets.
I have had to raise the Print Bed to accommodate the taller Aluminium Y Rod Holders.
I have separated the Y_Axis_EndStop from the Y_Rod_Holder to enable me to move the location to suit.
The AM8 is screwed down directly to the IKEA LACK table top base, and I have attached the supplied rubber feet to the bottom of the table. The table provides a flat base and using it simplifies getting the X Rods horizontal prior to levelling the Print Bed. If you have flexible rubber feet on the frame base then you have no idea if the X carriage is level with the bottom of the printer base.
The problems I encountered during the build are on the next page AM8 Build Issues.