Here are a couple (or more) of big item prints I have designed.
The tissue box I designed for my own office. The olive green one. Then I noticed a new but bare tissue box out in the music room where my wife provides piano lessons. Thus the white-ish box was born. When she noticed the new boxes, she immediately wanted several more made. Number 5 is on the Mamacetus printer as I write this. Print time per box is over 12 hours.
Next project is what I call a K-cup stackable pod rack. There are three here holding 27 pod cups. Less space by about 1/3 of the rotating wire rack I have been using and holding 3 more pods Another rack on top of these would equal the height of the wire rack. So 12 more pods in the same space. It's also a good excuse to design/print something.
Ordered a TinyFab ESP32 CPU to convert one of my Tiertime Cetus printers to Marlin gcode CNC operation. It is still in BETA so I am jumping in early on this.
The Tiertime folks have control software called UP studio ( V2 & V3) but it has always been a bit awkward to use if one wants total printer control. Their software is intended to out-think the user. I have made great prints using it but I have to compromise to using their quirks.
Just recently UP Studio (both versions) are refusing to display properly on my WIN10 computer, so time to try alternative control methods. Oh yes, on older hardware the the new UP Studio causes random print pauses where everything freezes and the nozzle drops a big blob. No fix in sight. Tiertime says to revert to older software... That's not a fix.
I believe the ESP32 indicates it is a 32 bit processor and that should make it pretty much state of the art as small CNC controllers go. Info says it is compatible with Simplify3D control software, which I fully understand how to use.
Apparently the ribbon cable shown attached (in the picture) is a connection for a LCD display and manual controller. I am learning as I progress on this project. I simply want to have standard gcode control for a starter.
From the TinyFab website I see they have a complete electronics swap out if I ever desire to go that far.
Cetus printers have one very significant issue and that is bed leveling. There is NO MANUAL leveling with stock Cetus. Heated bed is available (I have one) but the cable and cable sockets are a weak point as they are unable to carry the high current. For that reason I have my heated bed disabled to prevent fires. Yes fire. I have had one.
I am not going to spend a lot of T&E (Time and Effort) and money fixing everything with Cetus. It does work as-is and it does a good job for the original cost.
Will certainly report how the new CPU runs with Simplify 3D.
Just call it ASA. It is a 3D FDM printer filament. It is a plastic that is similar to ABS (Acrylonitrile Butadiene Styrene). Note they have arranged the triple name components a bit differently. The butadiene is missing and acrylic is first. What all that means is mumbo-jumbo chemistry to me. It does mean it has different properties.
ASA acts like ABS but is claimed to be stronger, more weather resistant and less subject to the effects of (UV) Ultra Violet radiation. Result, it should last longer in an outdoor environment.
That is why I bought my first kilo spool. I had a ham friend who wanted weather resistant plastic parts for a mobile radio antenna for his vehicle. I made some samples from ABS because I had some. Then I did research and discovered ASA and its better outdoor resistance especially to UV radiation.
I re-printed all the mobile antenna parts and then made end insulators for use with wire antennas.
ASA prints very well. Temps are high at the 250 C range. Warpage is far less than ABS. With good bed adhesion (glass + hairspray) I have been producing excellent parts.
My son-in-law asked for some parts made for a Yakimo bike rack on his automobile. I immediately recommended ASA rather than ABS for the parts since it would outdoors and subject to a lot of UV sunlight.
I had red, blue, and white ASA on hand. I suggested he could purchase a spool of black if that was the color he wanted for his bike rack. I now have black ASA on hand.
ASA produces a strong and rigid part. No flex in a thin wall can cap I printed in black ASA. Shown in picture with bike rack sample parts. I just a few days ago used red and blue ASA to reprint a mailbox flag I printed in ABS two years ago.
The ABS flag was structurally fine but showing a bit of color fade. The ASA replacement is a real world UV test in exactly the same location. A gave the old flag to my neighbor as it was perfectly useable. (No ABS from me in a landfill yet.)
In summary, I think ASA is a great material for printing. Parts are good. The jury is out on the UV claims, but I will accept the printed specs. ASA is priced higher than ABS and other “standard” filaments. Not an issue for me for the claims of better outdoor durability. ASA is for printing real application durable load bearing parts. Not decorative shelf Junque. :)
I print them four at a time but there is no time savings in doing multiples. The print time for four (one chair) is six hours. Total print time for all 36 pieces was 54 hours.
The material used is called TPU which is Thermal Plastic Urethane, a rubber material. Very tough and durable once it has been printed. Very good for this use.
I made a TPU (RED) case for my Apple SE cell phone. This too was a great application. I earlier posted some other red TPU prints in this blog. I now have to look for other uses for the TPU material.
Now that I have mastered the process for printing TPU, more projects with TPU will soon be underway.
The Cetus printers do not have any mechanical leveling of the build plate. It is bolted directly to the linear bearing with three small screws with no method of adjustment. What you have for level is fixed.
The leveling is done by using a four-layer raft and a four-layer base support on top of the raft. The first layer of the raft is 300% over-extruded and squishes out broadly. This heavy first layer and the buildup of the raft and support eventually results in a build surface that is parallel to the X and Y axis. Then the print is started on top of this level surface.
The result is the use of a lot of filament material to build a flat working surface. With a Cetus printer, one throws away a lot of raft leveling material at the end of the print.
The raft and support do not provide a nice polished build surface for the base of the print. The print bottom is always ruff like about #80 grit sandpaper. I usually “flame polish” the bottom to remove the little sharp points, but the surface is still quite a bit grainy.
I have installed a 3mm thick sheet of borate glass 200mm x 200mm using binder clips on the Cetus build plate. I simply tolerate the bit of non-level of the build surface. It is a bit larger than the 190mm x 200mm Cetus bed. I can live with a bit of overhang as well as the level issue.
I have to remove the ~5mm excess nozzle calibration height to get the nozzle low enough to print without the raft and support layers.
What I get is perfectly smooth bottom prints from Big MamaCetus! (*Read the first line above again.) I can stick some thin Build-Tac on the glass for TPU and PETG.
I am exceedingly pleased to be able to print without the raft. Some prints may still need the raft if I run into serious leveling issues on a big print. I have had no serious issues with prints up to 100mm diameter so far. First layers may be a bit thin on the high side but as long as the low side will stay attached to the build surface, the second layer evens out the height. I can not see this slight deviation in any of my finished prints.
Big MamaCetus is a MK3 with a heated build surface and the auto level probe. Early electrical problems have been resolved. (See previous posts.) I still consider the flexible power ribbon connected to the heated bed a weakness in design of the MK3. Careful protection of the cable must be maintained. I know to be careful.
The picture shows BMC printing a PETG cap and the glass build-plate with build-tac surface. Nozzle temp is 240C and the bed is 85C. 55mm/s speed. The print is excellent.
Using wax base filament for FDM printing models for Lost Wax Casting (LWC) master models.
3D Printing operation details will be published here. The casting and finished art will be presented elsewhere with links provided.