The room temperature is around 24°C, and you’re using ABS with a 0.14mm layer height and a full infill (“solid”). The supports are set to “light,” and you have 6 layers for the top and bottom surfaces. You’re considering using normal supports to improve adhesion to the raft.
Given your need for high mechanical properties and the exposure to UV rays, it seems like Z-ABS and Z-Ultrat are the only suitable materials.
I understand your concern, especially with a gearbox case that will take over 30 hours to print. Trying Z-Ultrat is a good idea, but you’re not entirely confident in the result.
Printing large, thin parts can be challenging, and adhesion issues are common. You might want to consider a few strategies to improve your prints:
Enclosure: Create an enclosure around your 3D printer to maintain a stable temperature. This can help reduce warping issues with ABS.
Brims or Larger Rafts: Increasing the size of the raft or using a brim can provide better adhesion to the bed and help prevent warping.
Slow Printing Speed: Reducing the print speed can sometimes help with adhesion and reduce the chances of parts detaching.
Cooling: Adjust the cooling settings to minimize temperature differences between layers, which can contribute to wrapping.
Bigger Nozzle: If your 3D printer allows it, consider using a larger nozzle. A larger nozzle can lay down more material, which can help with adhesion.
Regular Maintenance: Ensure your 3D printer is well-calibrated, and the bed is level. Regular maintenance can prevent issues.
Experiment: It’s a good idea to try different combinations of settings, materials, and support structures to find what works best for your specific parts.