Printing 2x6 beams

Hello all,

This is my first time posting, and i am looking for some thoughts from people who have extensive knowledge on 3d printing materials. My goal is to print 8' long 2x6 beams for a tent, the tent would need to hold up a canvas cover with a total weight of less then 60lbs. my real concern is what is going to hold up to strong winds and the stresses of being moved and set up over and over. i plan on finishing the pieces with a UV protective coating so sunlight is not a major concern. each "beam" would be composed of 8, 1' long printed parts affixed together with bolts.

what do you think the best material would be for this? (i was thinking ABS or nylon)
what are your concerns about longevity? (will these "beams" last 10 years assuming they will be outside less then 15 days/year)
how much infill would you recommend?

thanks for your help,
Cain.

forget abs. Not strong ebough and does not fare well if exposed to the elements.

Forget nylon as well, not rigid enough and length of nylon that long will be really bendy.

Okay - I hate the way nobody ever explains what they actually mean in imperial measurements.

Am I right in thinking you want to make 8, 1 foot lengths that are 6 inches wide by 2 inches thick ?

In what orientation will the beams be used ?
If vertical then nylon would probably work.

A 2 inch by 6 inch beam of almost any 3d printer filament will be sufficiently rigid fo the job.

Pet-g would work well, as would pla. 3d printed abs isn't great and really doesn't fare well outside.
If you can afford that much nylon, then it would work too.

what printer do you have ?

OK so my plan was to print 8, 1 foot lengths(not including a tongue for connecting them together) that are 6 inches wide by 2 inches thick (preferably not solid) that i would then connect together using bolts to create 1, 8 foot beam that is 6 inches wide by 2 inches thick. i would make several of these beams and connect them together in an A frame. i want to print the "wood" structure for a tent like this so that they are lighter and maybe even can come apart into 2, 4 foot lengths that would be easier to transport.

Attachment 13089

the beams that go horizontal i planned on printing "sideways" compared to the mostly vertical pieces so that i would have less issues with sheering. i worry that PLA will warp under the heat of the sun and stress of the canvas/wind. i figured the elements would be less important as long as i sealed the print when it was complete with a finish that is waterproof and protects from UV, am i wrong about that? but PETG does seem like it might make a good option.

I am currently using a Ender 3, but will be getting the SnapMaker 2 before i start printing this project.

Riiiiiigghhttt, now it makes sense.
For a tent like that - absolutely no problem. Plus it makes carving the patterns in part of the build process :-)
Painting them to look more woodlike would be a good idea.
Although a nice woody brown might work just as well.

Pet-g is the way to go. It can be a right bastard to get the setting right, and it doesn't print that fast - but get it right and it's ridiculously strong and less dense than pla.
Abs is awful outdoors.

Don't get me started on ender 3's - but if yours works - use it :-)

Didn't think the snapmaker had a particularly large build volume.

Don't understand where all this nonsense about pla is coming from. I've had pla things outside for years - in the english weather. Apart from the colour leaching slightly, they're as good as they were when they were made.

As far as infill etc goes. shells and outlines are what gives real strength.
So I'd probably go for something like:
5 shells, top/bottom layers and 40% infill.

scale down to test print settings.

Thanks I will give it a shot, do you have any recommendations for print settings in petg? I have done a few very small prints in petg but that is it. Also the sbapmaker 2 A350 has just over 1'x1'x1' print area

can I suggest you start thinking in millimetres :-)
It'll make you life easier in the long run as pretty much all the software defaults to metric measurements :-)

Ah hadn't looked at the new snapmaker. It's one of those printers that pops up on facebook ads.
so the new big one is 320x330x350.
Nice.
Good specs. have to admit it looks impressive on paper (well led monitor anyway)

1.6watt laser too - it'll struggle on some wood, but that's about as high as I've seen for an all-in-one machine. You won't cut anything but cardboard, but should engrave most things reasonably well - if slowly :-)

Tell you something else as well. We've never had a snapmaker owner on here. A reasonable indication that they don't go wrong often and the software works without leaving too many questions to answer.

Not cheap, but for an all-in-one hobby machine - not overpriced either.

Any idea when you'll get it ?

Ah - website says ships in march 2020.
So realistically, probably nearer november or december :-)

I'd suggest you start modding the ender 3, as you'll be using it for at least another year :-)

I ordered it on kikstarter with a delivery date of Jan 2020 so i am expecting the first half of next year(especially since they raised over 7 million dollars i would hope that helps keep them on schedule). also i am glad that someone with more experience thinks it looks like a good unit. it will be my first. the Ender 3 i am using is actually a coworkers, and i only have access to it at work. but it does have some cooling fan mods and a dual drive extruder mod. it can be a bit finicky but it works well enough for the small stuff i want to make at work.

the snapmakers modules are a really neat idea. Just a bit pricey for me :-)

Yeah, kickstarter money and how efficient a company is - are totally unrelated.

Given that this is their second go round, is encouraging as it means they are still trading :-)
Which for 3d printing kickstarters, is pretty rare.

engineers tend to make lousy accountants and budgeting isn't always done properly.

But fingers crossed :-)