Problems with Micro Swiss All Metal Hotend (Wanhao I3)

Micro Swiss All Metal Hotend

If you follow the blog you know I have a 3D printer, a Monoprice Maker Select v2.1 to be exact. Over the holidays I received the Micro Swiss All Metal Hotend Conversion Kit for the Wanhao I3, I got the one with the slotted cooling block, which I’ve seen recommended. The original cooling block uses a set-screw against the thermal barrier tube. The slotted block doesn’t use a set-screw instead it is slotted and you clamp the tube in place. Much better heat transfer.

I watched a few videos, read and followed all the directions, as well as I follow a few groups for 3D printing on Facebook (tons of useful info there!) and I have seen tips here and there. But I ran into problems with my install and could not find the information I needed anywhere. I even asked the groups and no useful answers really. As I said I followed all the directions and my issue came in to place with the 1.7mm of space you are supposed to leave sticking out at the top of the cooling block. I did this (a lot of videos they just eyeball it) and this turned out to be my problem.

When I first tried to assembled it all back together the custom lever plate I had printed and was using would not fit. The thermal barrier tube was sticking up too far. I use a printed lever bracket for the extruder. This bracket allows me to print flexible filament (which I have not yet). The stock plate leaves a gap that the filament can squish through, I have switched to this a while back. The bottom of the plate is flush on the custom one. The stock plate there is a rise, about 1.7mm it looks like.

I initially thought simply this plate wasn’t compatible and was going to just find another. So I installed the original plate instead. (After writing this post and searching for the links to accompany it I discovered there is a Micro Swiss version of the back plate that I was using. This will sit flush with the 1.7mm rise the instructions say to leave, but this still would not have solved my leveling or screw hitting problem.)

But that didn’t work everything was way too far away from the heat-bed. I tried to re-level but I could not get close enough. Also, the cooling fan I use was now hitting the bed screws that stick up slightly (all more reason to recess the screws!). Something was off and didn’t fit right.

At my wit’s end and feeling frustrated I took a break and left for the day. I came back later that night to hit at it again. This time I started wondering about the aluminum lever plate Micro Swiss sells and what the bottom looked like. Is it flush or does it have a rise and require the 1.7mm extra?


I Googled around and looked at images and it turns out the machined lever plate they sell is flush, just like my custom plate I was using. So I decided to forgo the instructions and remove the 1.7mm rise and make it flush so the plate will sit on it. Fifteen minutes later after reinstallation (for the 3rd time) and I was printing. After making the tube flush the plate now fits, my bed now levels and the cooling fan no longer hits the bed screws. So fuck the instructions, they caused me grief and didn’t work.

Not sure if this is a one-off install or if this is standard for using a flexible filament plate or the machined Micro Swiss plate.


TLDR; The original instructions say to leave 1.7mm of the thermal barrier tube sticking out of the cooling block. This will only work if you are using the stock extruder lever plate that came with the printer. If you are using the machined lever plate from Micro Swiss or a custom printed flexible filament plate from Thingiverse you may need to forgo the instructions and make the thermal barrier tube flush with the top of the cooling block. Read above for more details.

This may just be a one-off install YMMV.