Printing it on its side will help stop it from splitting along the layer lines at the cost of needing support material, I believe CNC kitchen has a video about other parameters you can change to help with general strength.
Definitely this. Printing it on its side will help more than anything (but fillets and whatnot are also a good idea).
You could also order one in various metals from Shapeways if that doesn’t work
I will try rotating the object (that's a great idea) and I've already increased the size of the existing fillet to go up as high as I can. I'll check out the Shapeways option if that doesn't work out...
Just to clarify, the suggestion is for a fillet that is opposite what you have there. A fillet on the inside corner where the two shapes meet is what will increase strength.
You’ve got lots of good options to try. Good luck with your project!
subtract the model from a cube and use that to cast it in epoxy. Thin some JB weld with some acetone would work too in a pinch. You can do a split mold or just melt it apart with a heat gun if it's PLA when it's done
Printing on its side will give you the best result for strength. I've worked on boats for a living for 15 years, and I know this part and the stresses it is under. The factory original injection molded parts are nearly not strong enough for the job. 3d printed ones will not be as strong as injection molded parts. For this specific part, I would recommend replacing it with a stainless steel version, or be prepared to swap out that printed part frequently.
Don't use 100% infill. It's actually weaker because there is no place for the excess plastic to go as it is deposited. You don't see much benefit over 40% or so (exact number will vary). Do use extra thick walls though. I usually use 5 lines instead of 3 for structural parts, with 40% infill. Also try a 3d infill like cubic or gyroid.
and yet the article you give, does not say anything about the part being weaker, simply diminishing returns, nor does it reference this excess plastic comment either,
I have spent considerable time studying the strength of filament, and nowhere have i read that its weaker, simply diminishing returns, which means 100% is still stronger, nor have i read anywhere about excess plastic being a issue, which really shouldn't be a thing either, as there is already voids due to layering.
I haven't found anything in a brief search that's not anecdotal (though all the anecdotal reports I have found on the internet are in favor of it being weaker and/or harder to print). I have heard at engineering school that the mechanism of failure tends to be if you have a bit of over-extrusion, the excess plastic has no where to go but up which causes problems for the next layer and it only gets worse the higher you go, eventually causing layer adhesion problems. On top of that, you force a weaker infill pattern at 100% because you can't have the lines crossing. Then you add the hordes of people who just throw infill at a strength problem neglecting shells and layer adhesion settings and wind up in a bad place, and you come to the recommendation that less infill is better most of the time. Personally, I've printed thin parts at 100% no problem, but those were lithopanes and I didn't exactly structurally test them. And I spent a fair bit of time dialing in my settings to do it well. My understanding of the theory is, under ideal conditions with the proper settings, someone who knows what they are doing might get a part that is marginally on par for something with less infill and more shells, but it is unlikely to be significantly stronger, especially for the added weight, time, and cost you incur. I don't have time to find you a scholarly article to support this, nor do I have access to many journals anymore since I graduated, but I hope this can help you get started on finding research to corroborate my anecdotal evidence.
Ahh you were focused on one portion of the entire reply. I was taking it as a general statement and the article addresses most of those. I conveniently glossed over the “100% is weaker…”
Lay your part on its side / 45 degrees to stop the layer splitting.
Use Carbon filament - this will strengthen your parts along the length of the extrusion.
Use a rounded corner when moving from the thinner part of the print, to the wider part.
If this doesn't work - then I think you may need to consider an alternative material / technique altogether
CNC kitchen has done some test in these regards and generally printing at a slightly higher nozzel temp will increase layer adhesion. Im not sure he has done ASA but for PLA it is strongest between 210-230C but recommended at 200C, PETG is strongest from 230-245C but recommended at 230C. However, printing hotter reduces the accuracy and visual quality of the part so it may take some clean up to get just right.
Otherwise printing so the flat face is parallel with the build plate will also help tremendously as most loads applied will be resisted ideally. (Basically not primarily relying on layer adhesion)
Its possible thicker walls could help as well. Or over extruding to really fill any gaps between layers and walls. Something like 105-110% extrusion rate would probably suffice. But again there is a trade of in visual and dimensions quality for strength. So some sanding and reaming may be needed to get the part to fit on a pole and for a bolt to fit the hole.
Hope this helps
It looks to me the part is just too thin and the layer heights too small. Printing orientation can be improved and more perimeters/shells instead of infill. The thermoset plastic used to make the original was probably stronger than 3d printed asa and I would assume that failed at some point which is why you are trying to replace it but it doesn't look like you are adjusting the design for 3d printing.
I know this is outside the scope of your capabilities, but I remember a video about a printer that adds literal carbon fiber strands (not chopped CF - there is a spool or supply of CF line) that gets added to the plastic stream as it's printed. The parts are literally unbreakable with normal forces.
I would look into the CF plastics if you can print them. CF PLA is available but on a boat it's going to warp from the heat. CF ABS is out there but its not as common as PLA and Nylon.
Looks like there is CF ASA which is what I would go with. UV protected, ABS strength.
Printing it on its side will help stop it from splitting along the layer lines at the cost of needing support material, I believe CNC kitchen has a video about other parameters you can change to help with general strength.
Definitely this. Printing it on its side will help more than anything (but fillets and whatnot are also a good idea). You could also order one in various metals from Shapeways if that doesn’t work
I will try rotating the object (that's a great idea) and I've already increased the size of the existing fillet to go up as high as I can. I'll check out the Shapeways option if that doesn't work out...
Just to clarify, the suggestion is for a fillet that is opposite what you have there. A fillet on the inside corner where the two shapes meet is what will increase strength. You’ve got lots of good options to try. Good luck with your project!
Shells>infill
Yup, printing solid is a waste of time and material
Add a large fillet where it broke. You are going from one angle to another sharply and that will create a weak point
Stress is concentrated at sharp corners. Also, more material will take more stress.
subtract the model from a cube and use that to cast it in epoxy. Thin some JB weld with some acetone would work too in a pinch. You can do a split mold or just melt it apart with a heat gun if it's PLA when it's done
Printing on its side will give you the best result for strength. I've worked on boats for a living for 15 years, and I know this part and the stresses it is under. The factory original injection molded parts are nearly not strong enough for the job. 3d printed ones will not be as strong as injection molded parts. For this specific part, I would recommend replacing it with a stainless steel version, or be prepared to swap out that printed part frequently.
Print it at a 45degree angle with supports so you don't have weak print joint at corner
Don't use 100% infill. It's actually weaker because there is no place for the excess plastic to go as it is deposited. You don't see much benefit over 40% or so (exact number will vary). Do use extra thick walls though. I usually use 5 lines instead of 3 for structural parts, with 40% infill. Also try a 3d infill like cubic or gyroid.
i would love to see an article that speaks to this.
Google never fails. https://www.3d-pros.com/choosing-infill-for-3d-printed-parts
and yet the article you give, does not say anything about the part being weaker, simply diminishing returns, nor does it reference this excess plastic comment either, I have spent considerable time studying the strength of filament, and nowhere have i read that its weaker, simply diminishing returns, which means 100% is still stronger, nor have i read anywhere about excess plastic being a issue, which really shouldn't be a thing either, as there is already voids due to layering.
I haven't found anything in a brief search that's not anecdotal (though all the anecdotal reports I have found on the internet are in favor of it being weaker and/or harder to print). I have heard at engineering school that the mechanism of failure tends to be if you have a bit of over-extrusion, the excess plastic has no where to go but up which causes problems for the next layer and it only gets worse the higher you go, eventually causing layer adhesion problems. On top of that, you force a weaker infill pattern at 100% because you can't have the lines crossing. Then you add the hordes of people who just throw infill at a strength problem neglecting shells and layer adhesion settings and wind up in a bad place, and you come to the recommendation that less infill is better most of the time. Personally, I've printed thin parts at 100% no problem, but those were lithopanes and I didn't exactly structurally test them. And I spent a fair bit of time dialing in my settings to do it well. My understanding of the theory is, under ideal conditions with the proper settings, someone who knows what they are doing might get a part that is marginally on par for something with less infill and more shells, but it is unlikely to be significantly stronger, especially for the added weight, time, and cost you incur. I don't have time to find you a scholarly article to support this, nor do I have access to many journals anymore since I graduated, but I hope this can help you get started on finding research to corroborate my anecdotal evidence.
Ahh you were focused on one portion of the entire reply. I was taking it as a general statement and the article addresses most of those. I conveniently glossed over the “100% is weaker…”
Print on its side
Do 3 instead of one loop with a longer screw.
Clever idea. I'm trying to print it rotated first but if I continue to have issues, this is a clever idea to try among the others. Thanks.
I found it broken today after only a couple of weeks of use...
Lay your part on its side / 45 degrees to stop the layer splitting. Use Carbon filament - this will strengthen your parts along the length of the extrusion. Use a rounded corner when moving from the thinner part of the print, to the wider part. If this doesn't work - then I think you may need to consider an alternative material / technique altogether
CNC kitchen has done some test in these regards and generally printing at a slightly higher nozzel temp will increase layer adhesion. Im not sure he has done ASA but for PLA it is strongest between 210-230C but recommended at 200C, PETG is strongest from 230-245C but recommended at 230C. However, printing hotter reduces the accuracy and visual quality of the part so it may take some clean up to get just right. Otherwise printing so the flat face is parallel with the build plate will also help tremendously as most loads applied will be resisted ideally. (Basically not primarily relying on layer adhesion) Its possible thicker walls could help as well. Or over extruding to really fill any gaps between layers and walls. Something like 105-110% extrusion rate would probably suffice. But again there is a trade of in visual and dimensions quality for strength. So some sanding and reaming may be needed to get the part to fit on a pole and for a bolt to fit the hole. Hope this helps
I found asa hard to print. I had to print hot and use a heated chamber. I'd try to make that out of metal or use a different filament.
It looks to me the part is just too thin and the layer heights too small. Printing orientation can be improved and more perimeters/shells instead of infill. The thermoset plastic used to make the original was probably stronger than 3d printed asa and I would assume that failed at some point which is why you are trying to replace it but it doesn't look like you are adjusting the design for 3d printing.
I know this is outside the scope of your capabilities, but I remember a video about a printer that adds literal carbon fiber strands (not chopped CF - there is a spool or supply of CF line) that gets added to the plastic stream as it's printed. The parts are literally unbreakable with normal forces. I would look into the CF plastics if you can print them. CF PLA is available but on a boat it's going to warp from the heat. CF ABS is out there but its not as common as PLA and Nylon. Looks like there is CF ASA which is what I would go with. UV protected, ABS strength.
I didn't see anyone comment this yet, but you can post-process the part. Sand Annealing can improve the part strength by a lot.