3D Printing Parts

[techtownmayor]

It all comes down to the type of machine and type of plastic used. A cheap FDM machine using PLA will print something that will probably fail in a year. A mid-grade printer using brand name ABS should be able to make a part that’ll last for years. 

Sadly, if there is one thing I’ve learned from my own 3D printer, it is that it never prints as fast or as affordable as you wanted 🙂

Good luck!

[olivero]

I believe it.

My plan is to get the Monoprice Ultimate 3D Printer II, using PETG and I’ve printed a sample in ABS with someone else’s and it comes out nice, I just plan on making it indestructible.

It’ll still be cheaper than $3.50 a piece I hope. If I can keep the part under 100 grams then it’ll be cheaper, I’m looking at about 40 grams including supports and that’s with the part modified for extra strength.

[olivero]

Here’s a picture of it printed in ABS with about 10-15% infill.

[techjoeb]

So the problem with 3D printing any parts is knowing if the plastic has 2 very basic requirements:

1. Is it food safe. Will it be OK if a customer ingests those pieces of plastic? If the answer is no, you leave yourself open to all sorts of liability issues. 

2. Will it put up with the temp? Most ware-washers will start at 140 degrees F and go past 180F. Most 3D plastic will soften at those temps. 

[olivero]

Hey Techjoe,

That is a good point and one that I have considered. PETG is considered food safe and depending on how the final product comes out, it’s either food grade or not.

PETG has a heat deflection temp of approximately 65*C – 80*C depending on who you ask. 

I would think considering that the machine is designed to bring objects to 160*F +, the peg will have to resist at least 160*F but I don’t think it’ll get much hotter than that, the PEG itself is plastic so it’s conduction is going to be low and it will be exposed to those higher end temps only for a short period of time and then end up back in room temperature for a little and then back through.

Once the object hits the heat deflection temp it then becomes flexible but I think it would take some effort for the entire part to hit that temperature.

But I won’t know till I try it.

[techtownmayor]

A great article listing 3D filament with food grade approvals is here: https://3dfilaprint.com/filament_overview/food_safe_filaments_print.htm

Of course, the whole “approved” vs “cleared” debate is really complex, and too often, a company will make claims about their products they can’t back up. 

BTW; what a fantastic topic! There is very little information out there about 3D printed food grade parts, so I’m sure this thread will be a great resource. 

[olivero]

Awesome, good information on there, there’s definetley a lot of options, just a question of which ones will work best on what printer, seems like some of them require a specific kind of printer with more than a heated bed and all metal hot end.

Yeah, it’s amazing how little information there is, seems like occasionally and end user will post something about it somewhere but there’s really not a lot of info.

When I do get the printer in with the PETG I’m sure I’ll find many, many reasons to use it and I’ll be able to do a lot of perfecting and testing.

[ectofix]

Olivero, we have eight Hobart flight machines.  Our labor efforts to keep up with replacing broken flights is ridiculous.  

Once you settle upon what type of plastic to use, I suggest installing just a limited number in a location that you can easily track them down so you can closely monitor their durability over the long haul.  I recommend that before making any huge investment in the additional materials and time to make/install a bunch of them.

Those flight have a rough life – not only in temps approaching 200° and harsh chemicals, but also by the abuse they incur by the stewarding folks cramming dish wares into them for 12-18 hours or more a day.

[olivero]

Ectofix,

I know, it’s ridiculous how many of them break, the main thing will be making sure that the PETG can survive the temps, that’s really my main concern as I can keep modifying the design of the Peg to make it stronger but if the plastic won’t survive the temps then it just won’t work at which point I’ll have to find another material.

I want a 3D printer regardless as I’m sure it’ll come in handy for all the little things that break where replacing the whole thing is the only way to fix that little part.

[fixbear]

The selection of a plastic material is quite complicated. It involves not only food service and temperature,  but also environment and chemicals that it will be exposed to as well as the big de grader, UV.  Consult with the makers chemist to get the best one for your application.  It’s a ever changing industry with new compounds coming out often.  The US Navy has now gone to having a printer on board all ships to cut down on parts inventory.  But those level of printers are problably out of our price range.