What’s the recommended or best filament to use for a building driveway garage entrance corner bumper protector? BL TPU95 seems too plasticky and does not sufficiently absorb energy from car impact.
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The answer to your question requires a lot more information.
- What is your objective? Is it to protect a fixed object or the vehicle?
- Is it intended to be a single-use crash attenuator or a sturdy guard against wear and tear on the corner of a structure?
- Will it have to absorb impact or simply momentary abrasion?
- How long do you expect it to last?
- Physically, what dimensions do you expect the final part to look like?
- How do you expect to mount it and to what kind of surface?
All of these questions and likely more would help in aiding you on some recommendations. If I were to hazard a guess from the limited information provided, a 3D printable substitute for the object you show in your image is likely not a practical approach but there are methods to achieve the same objective if we knew what that might be.
Also, a link to the object you’re trying to emulate would help. That might answer most of the physical property questions you are asking.
A corner bumper protector on a concrete wall, driveway into a building garage. That is the use-case and objective and market product example.
All other points are secondary and can be whatever aka are irrelevant. Just need basic ideas and thoughts on which filament you recommend.
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Well, you asked, I offered, but if there is no desire to answer any of the key questions, then I’m afraid I can’t help. Good luck. Consider that there is more to the choice of filament than just the material; it also depends on how the internal structure is designed. One can create a very hard material with TPU, but an equally flexible material can be designed using PETG if one knows the methods. However, since it’s such a hassle to provide key information, good luck.
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Is it to protect the car from scratches or the wall from damage ?
For the car I would go with TPU95, or if that’s too tricky with plain PETG.
If the protection is meant for the wall the issues are totally different.
At work we have one of THOSE corners…
Must be cursed or such as it really is not hard to avoid it.
Never mind all the bright yellow paint on it (flour) nor the three big signs reminding people to stay on the DRIVEWAY and to not use the lawn when turning…
Anyway…
We tried various commercial and home made solutions to keep the brick layer out…
In the end we settled for shaving the corner at a 45 degre angle and to cover it with 5mm stainless steel corner that has the missing bit of the wall added with a 10mm plate.
It looks badly scratched and has a few dints now but the wall won’t mind.
Some drivers did not like the measure though after seeing what it did to their cars or vans…
Did you know that you can hard PU corners for not really that much money?
Usually a 50 or 100mm profile.
Drill holes as required and rest assured the stuff will tolerate a lot of physical abuse while not causing and scratches on paintwork.
If you buy those in bulk, cut them and smooth the cuts it will come cheaper than printing them in bulk quantities…
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Hard to improve on the @Olias answer. But keep in mind that wall thickness and fill % plays a HUGE role in how TPU responds to impact and/or feel. When I print TPU, the infill is never more than 5-10%.
Also not mentioned is whether the model will be exposed to sunlight. UV light can play havoc with many of the filaments.
Thanks for the responses and input!
Goal is to print instead of buy a corner protector bumper guard. These corner bumper guards protect both the wall and car. Sizes up to max limits of X1. Is to be used outdoors, exposed to UV and the elements.
The best commercial solutions are rubber based as best at absorbing energy on impact. My question is which material is best at absorbing energy without breakage? Infill suggestions for this use-case?
TPU is what you want to use or another filament from the TPE family, there are many shore hardnesses depending on how much you hate yourself. 82-95a is the most popular range for FDM printing and 95a is one of the easiest to print the lower the number the softer the material but it comes with the problem of being harder to impossible to print. Have a look into shore hardness to get up to speed.
Depending on how you slice your print will depend on the properties it gives, so if you print 95a with thick walls and high infill it will be solid whereas if you have thin walls and less infill it will be a lot more flexible.
It’s the filament for the job, you just need to design and slice the part in a way so that it gives the required properties.
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AFAIK, polycarbonate will absorb pretty much whatever force you throw at it like it never happened. If you doubt it, try beating a piece of Lexan. You might scratch it, but you won’t break it. I have a 3 foot wide sheet that’s just 5/32" thick, and even after scoring it multiple times, I can’t even bend it enough to snap it. So, in terms of a literal answer to the title question, it would be hard to top it, without getting into glass fiber or carbon fibers. Presumably those would be even more resilient.
Less extreme: there now exist flexible PLA’s… Not sure if it meets your criteria, but maybe worth giving it a try?
Do a simple test with PETG:
Print a few short strips that are thick enough for the purpose.
Try to print them upright so the layer lines go around the corners.
For the first use three walls and a 25% triangular infill.
Print another one with 3 loops but a 10% gyroid infill.
Last but not least - repeat the above using just ONE wall loop.
Place on some old brick and grab some things to give those strips a good whacking…
Please don’t use the kettle or other things your wife might find vital…
You will find that PETG is quite sturdy while barely being able to cause scratches.
You need something soft and leave rough edges on the print in order to cause a scratch.
Depending on the number of walls, their thickness and the type/density of the infill you get a lot of room to play with…
IF you would print in some translucent or transparent PETG you could even include some LED’s for the night…
For TPU the options are nearly limitless though.
Many different types, including foaming ones allow for any hardness you like.
For the daily drive I would go with PETG and call it day.
For that Lambo I would go with a soft TPU modelled like a honeycomb to give it some thickness and lost of forgiveness before anything vital is stopped by the brickwork…
But then again - I might just go to the local hardware store and buy some silicone corner protectors in the child safety department for 5 bucks.
Placed where the car would have a chance to meet the corner and Bob’s your aunty 
Soft materials will just pass the impact force through to the corner in a small area, so the wall structure is still at risk. Protecting the wall requires a hard, low friction material, such as steel, that can spread the force over a larger area. Smooth, hard plastic might reduce paint damage, turning scratches into scuffs as the car slides past.
Anything you can print on a Bambu printer will be well under 360mm long. Fastening to the wall will require an adhesive and/or many holes for fasteners. Both methods will cause permanent changes to the structure. Holes near a corner will weaken it substantially, so the material would need to be fairly wide, 100-150 mm per side.
Many times 3D printing is not the solution. The effort here would probably be better spent on driver training.