Qidi Plus 4 Closeable Ventilated Riser

                                               Qidi Plus 4 ventilated top riser

Update 11-10-'24 : Added 2 files, see below

Update 16-10-'24 : Added an explanation for the Foam template file, see below

I recently bought the new Qidi Plus 4 printer and experienced a clog caused by heatcreep on the second print. As the Qidi interface display tries to remind you with each print that you should leave the door and glass top open when printing PLA or PETG, I still forgot to do just that. 

I decided I was going to design a ventilated riser unit with closable grates, to prevent such an occurance to repeat itself.

 Designing was pretty straight forward and this is the result. Since it took me a good week to design, test print and finalize the uploaded models, this model is for sale and not like my other stuff for free. A man needs to eat and pay his bills too once in a while. 

I have been printing with the prototype on the printer for a week now and with both PLA and PETG I have the door closed and the glass top in place. All grates are open and during long prints, 22+ hours, the chamber temperature never reached above 40C. 

I also made a small modification to my extruder where I added a small air duct for better directing the cooling air at the hotend heatsink. This has already proven itself while printing without this ventilated riser unit. A few times while printing PETG I experienced heat creep, with door and lid open. Turns out the fan for cooling the heatsink is poorly placed and didn't have much effect in preventing heat creep. With this modification I no longer experienced the PETG heat creep issues. You can find the small air duct here. I recommend installing this small modification on your Plus 4, even if you are not using this ventilated riser unit. 

                                                                    The Build

All the parts can be printed on the Qidi Plus 4 and the parts in the .3mf files have been arranged for the Qidi Plus 4 buildplate, so you do not need to rearrange the parts. There is also no need for supports while printing this design. The .3mf files are project files, made in Qidi Studio slicer. After loading the files you can adjust every setting to your own specifications or simply use mine. It is important however to do your own calibrations of your desired materials, since these can differ quite a bit from brand to brand!! 

If you use my settings, the build requires about 1200 grams of PETG to print everything. 

Well dialed in filament and printer settings make printing this model a breeze. So take some time to find the best settings for your chosen filament and printer settings

It took me a few days to dial in my most used filaments on the Qidi Plus 4.  I found out the tolerances can be pretty tight with this printer if it is well dialed in! 

All the parts fitted really well. There are some areas you might need to use a file here and there to make edges a bit more angular. Some areas and wall loops are small and printing with a round string of plastic will always create some small rounded edges. This is nothing major, so the build should be pretty straight forward. 

You can follow the photos in this upload in the order they are presented, to get a good idea of steps to follow and what to do. The 6th photo shows the only tools I used, including the piece of PETG filament that I used as connecting dowels for some of the parts. 

                                              Test fit everything before you apply glue!!

Before you start glueing the front main and rear bodies together, clean the inside between the walls where the grates will slide. The opening is 3 mm wide and the grates are 2.6mm thick so they should slide easy. I found however, that because the area on which the grates need to slide was printed in bridge mode, the surface can be a bit rough, so sliding didn't go very smooth before cleaning the inside. Using a small file or some sandpaper might be needed to clean that bottom area up a bit. Just test if the grate slides in completely from the top and can move freely from left to right. When the grates are correctly placed, there should be about 1 to 1.5 mm clearance between the top of the grate and the top of the main body.  I needed to keep the tolerance in width verly tight here, because you don't want to have stuff rattling around when the printer is busy at full speed. 

Once every grate can slide freely in the main body, proceed with the glueing of the separated grate parts and follow the rest of the build steps.

On the tenth photo, where you need to connect the 2 front main body pieces, keep something behind the inner holes, so the filament dowels won't be pushed in to deep. This way you don't have difficulties with cutting the dowels in between the front and back wall! I used a file and when the glue was dry, I used the file to clean up the small protrusion from the dowels in between the walls. Make sure that the 2 front parts combined leave an opening of 7.9 to 8mm, ideally the same width as the rest of the openings in the front wall. 

If this gap is larger, the grate will not close off the holes properly on either the left or right side when it is in the closed position!

Connect the combined main back with the front and again make sure everything lines up correctly and the left and right grate can move freely front to back!  

                                                Test fit everything before you apply glue!!

Continue to assemble the top parts by following the order of the photos. When the top is fully connected, test fit the top onto the main body. It should snap right onto the main body, but you can add some glue if you want. Since the parts are going to be stationary, I didn't use glue between the top and the main body. The glass lid will provide some weight to keep everything in place, but you can always opt to add some glue anyway.  

In order to get enough clearance for the filament spool, I also needed to make a riser for the excisting spool holder. Remove the small black piece from the back of the printer and attach that to the riser block with 4x M4x20mm allen bolts and 4 regular M4 nuts. The original bolts that held the spoolholder can be re-used to attach the riser block to the printer. Once secured, you can slide in the spoolholder into the original piece. In the future I might make a different spoolholder, but after having tested this setup for over a week now, this works just fine. 

I made an optional glass top grip, with my “3D Mad Mesh” designer name. This will require you, if you know how, to do a multi color print. This can be done with a single filament printer, you can use google if you wish to learn how to do this. The grip is attached with the original hardware used for the standard grip. This is of course completely optional!   

                                                    Test fit everything before you apply glue!! 

I used cyanoacrylate glue for the whole build. Make sure your parts are clean and grease free for best adhesion. Slightly roughing up some surfaces with grit 180 sandpaper might provide a better surface for adhesion.  

     I will keep updating this text when I remember things I might have forgotten to mention!

 If you have questions or run into problems, please message me and I will answer as soon as possible to help you out!

Update 11-10-'24:  

• Added 2 thin strip to fit onto the lower connector. I noticed there is a gap of missing foam on either side of the lifting handles. This piece will fill the gap and add extra strength to the lower connection between the front and back lower ring. 

Update 16-10-'24:  

• The foam cutting templates are meant as a template to cut something like Moosgummi or Craft or EVA foam in perfect fitting shapes to put in the top of the riser. This foam is where the glass top will sit on instead of the bare plastic. I bought a pack of the coloured foam with sticker backing, that way I didn't need any glue to attach it. 
• Instead of buying foam, you can also choose to print the templates in TPU and glue that to the top sections. In the slicer use the scale feature to add some thickness to the models to get to your desired thickness. Remember to unlink the chain box or you will scale in all directions instead of just the Z direction!! 

Print settings: 

• Printed with PETG
• 0.4 nozzle with 0.4 wall thickness for outer and inner walls. Other thicknesses, like infill set to 0.45
• 0.2 first layer and the rest 0.25
• 20% grid infill
• For the filament holder riser block, I set an object modifier to print it with 8 walls and 25% infill

Hardware needed: 

• 4x M4 20mm allen bolts 
• 4x M4 nuts