Question about 3D printing

  • Hey Guest, We've had to cancel our 2020 Summer BushMoot PLEASE LOOK HERE for more information.

Tony

White bear (Admin)
Admin
Apr 16, 2003
22,036
631
49
Wales
www.bushcraftuk.com
Hey, I read the thread on the printed match case and I'd like to know more about the properties of the plastics in regards to heat, I like the idea of having a 3D printer for making the odd thing but life conspires against me, but it won't always!

So, obviously, the printer works by melting the plastic which is then formed into the shape desired, once the plastic has cured is it more resistant to heat or just the same as it was in its raw state?

So, say I want to make a handle for a fire poker, or a spoon say, is it feasible or should it be avoided if the plastic has any chance of getting hot? I'm not talking about putting it in the flames, but boiling water say...

Also, is it impact resistant? Although I expect that it's dependent on what plastic you use. I read in the other thread the bit about knife scales etc, how well would they stand up to the rigours of outdoor use?
 

nunzionuk

Full Member
Nov 29, 2010
863
2
Essex, UK
www.nunzionuk.net
From what I've seen/found. Once the filament (the Ink for the 3D printer) has been used, it has a lower thermal resistance than before use. With most having a melting range of 140c to 180c, so would be fine in boiling water, like most plastics, but would melt over a naked flame.

If you want to make a handle for a fire poker, you'd be better off looking at silicone, which you can make the molds for on a 3d printer, with abs or pla.

Hopefully that helps.
 

C_Claycomb

Mod
Mod
Oct 6, 2003
5,588
661
Bedfordshire
https://all3dp.com/2/is-pla-food-safe-what-you-really-need-to-know/

"A team of experts out of James Madison University (JMU) went on a mission to test PLA for various conditions and to evaluate how safe it was. They tested PLA under different temperatures and durations and using common ingredients found in food.

According to JMU 3SPACE classroom, the scientists discovered that “PLA is Generally Recognized as Safe (GRAS) when used in contact with food.” Their results are published in the 1995 issue (volume 33) of the Food and Chemical Toxicology Journal.

Despite their research findings, JMU warns of the dangers of PLA, which can be contaminated by hot ends of 3D printers. The potent mix of chemicals and heat used when printing and processing PLA pose a health danger. In addition, the coloring in PLA signifies the presence of an additive that is not food safe. Another concern is that PLA 3D printed materials have tiny holes and cracks that can accommodate harmful germs and bacteria."​
And,

https://all3dp.com/1/food-safe-3d-printing-abs-pla-food-safe-filament/

Materials:
https://all3dp.com/1/3d-printing-materials-guide-3d-printer-material/
https://www.3dnatives.com/en/plastics-used-3d-printing110420174/
https://www.3dhubs.com/knowledge-base/fdm-3d-printing-materials-compared


Some would probably work fine for knife scales, maybe not for a hidden tang, but there would be some that might be good for that too. No way I would trust plain PLA for that though, maybe for the full tang, but I can get better fit, finish and appearance with wood or Tufnol, and not have any worries, and do it in little more time than modelling simple scales and 3D printing.
 

Tony

White bear (Admin)
Admin
Apr 16, 2003
22,036
631
49
Wales
www.bushcraftuk.com
K, so it's useful and will be fine for lots of applications (more than I thought actually!) Still has lots of limitations though... Good point on time Chris, although I suppose that if you were repeating a process it would be quicker after the design side of things was done.
 

nunzionuk

Full Member
Nov 29, 2010
863
2
Essex, UK
www.nunzionuk.net
Wow.. i didnt know there was so many different types of filament!

3D printer is pretty much a, if you can think (and design it), then it will do it.. I've only have very basic things printed so far (mostly work related things, like cable management clips)

I saw the 3d printed matchbox that someone posted on here, that looks pretty cool.
 

C_Claycomb

Mod
Mod
Oct 6, 2003
5,588
661
Bedfordshire
....
3D printer is pretty much a, if you can think (and design it), then it will do it..
This is a common misconception, or maybe such a gross simplification as to be misleading. You could say something similar about CNC machining, and while designing for and setting up a CNC milling job is hugely more complicated and time consuming than designing for and setting up a 3Dprint / FDM job, getting a good 3D print still requires knowledge of the technique's limitations. Same as carving wood, or any other making process. I have seen more than enough parts either fail to print correctly because of printer problems, or because the design did not adequately account for printer capability.

The most forgiving additive process is SLS with an unfilled nylon powder. With that you get a uniform surface finish, do not need to consider support structures, don't need to worry too much about the print head dragging the model out of position on tall prints, and the material is fairly isotropic, and you can machine it to adjust fit.

I see a lot of this 3D printing stuff as solutions in search of problems. Although I make stuff and have repaired or replaced a number of things in both my home, and my parents', I can think of very few where a FDM part would have worked, mush less worked as well as the wood, Tufnol, polycarbonate and metal that I used.

For the cost of the machines, I advise caution before going out and buying one lest it turn out to be no more than an expensive and little used toy.
 
  • Like
Reactions: Broch

Toddy

Mod
Mod
Jan 21, 2005
35,497
1,617
S. Lanarkshire
Himself has one, and Son1 has two.

They are 'useful' for folks who want specific bits made quickly and easily, if you have a design or are good at designing stuff yourself. That said, there are masses of free patterns available on the net, but if you're after something that's not available, you have to design it.

My two have made bits for electronics, parts for a tremendous number of bits and pieces, like replacement screw caps, widgets, even a mini loom, loads of N gauge and OO gauge stuff for me, as well as 12th and 24th scale.
I have match cases, Christmas ornaments, fancy wee boxes, etc., made using the printers.
There have been more than a few pieces that didn't come out as expected though, so it's far from perfect, and it can be incredibly frustrating. I just leave Himself to it and keep out of the way when it's being less than helpful.

On the whole I think of them as fun tools to footer around with.
Would I suggest you get one ? hmmmm, yes, just speak to someone like Himself first, and don't bust the budget on it.

M
 

Janne

Guest
Feb 10, 2016
12,368
2,257
Grand Cayman, Norway, Sweden
I find the 3D printing technology incredibly interesting, but will never get a machine as I am 100%, totally useless when it comes to computers.

:)

I think some people just do not have the mindset for certain things.
 

Gary Elson

Full Member
Feb 27, 2007
206
188
55
Bulkington Warwickshire
Hi
Here’s my two pennoth worth
I teach engineering to some 200 students most of which will use a 3D printer in some way to provide components for final year projects
Yes it has limitations prints do fail mainly due to poor models produced at the CAD stage we use Solidworks
BUT it is far quicker process than CNC machining will produce accurate sizes I reckon to about +\-= 0.2 mm
It is still relatively new technology and prints are getting better all the time with the associated development of materials
These are far from “toys” and are already revolutionising areas such as bio medics and rapid prototyping
However like most good design choosing the right material or process is all part of the iterative process
Just saying !
Gary
 

Jared

Bushcrafter (boy, I've got a lot to say!)
Sep 8, 2005
2,534
99
47
Wales
3D printers melt PLA at over 180°C. Though has the glass transition temperature is as low as 60°C, so any thin or fine detail will slowly get lost.
Printing in ABS will be better, as it's glass transition temperature is 105°C.

Also reminds me of this guy... lost pla casting sword hilts... pretty cool.

https://imgur.com/gallery/qDcyq18
 

Robson Valley

Full Member
Nov 24, 2014
8,285
1,383
McBride, BC
Every once in a while, we get a "feel-good" piece of news. Usually, it's a squib of a story about some Brit
in a back garden shed with a 3D printer who has developed innovative prosthetics for people.
Always the Brits, always ahead of the R&D game.
 

C_Claycomb

Mod
Mod
Oct 6, 2003
5,588
661
Bedfordshire
All the mention of toys after I warned against the risk of making a hasty purchase makes me think people misunderstood what I was saying.

People buy all sorts of things that are meant as tools so that they can tinker and play with them, without ever needing them to do real work. There is plenty of gear that we buy because it is shiny, looks interesting, and is shown in use by rugged adventurous types in far flung exciting places. The reality though is often that it doesn't really suit and after getting patted and ahh-ed over it gets put away and used little, maybe just because the opportunity to really work it was never there in the first place.

I also have a certain amount of concern about the creation of more plastic waste. Do we really need more plastic Christmas ornaments and funky flower vases? Yeah, some of the plastic is meant to biodegrade, but not all of it will do. Also, if you wanted a plastic pot or some sort of box, before your printer, you might have re-used a pill bottle or found some other item to re-use, whereas post-printer you can make a brand new item, maybe needing to make it more than once in order to get it right. This is a two edge sword, you can use printed parts to keep things going that would otherwise be thrown out, but other things may not be re-used because it is quicker or more fun to print brand new. 3D printing carries an appeal for the instant gratification gene.
 
  • Like
Reactions: Woody girl

Tony

White bear (Admin)
Admin
Apr 16, 2003
22,036
631
49
Wales
www.bushcraftuk.com
Interesting stuff, it would be good in the future if you could get plastic waste and repurpose using the printing machines.
I like the idea of it, but I doubt I'll invest enough time to make it worth having one, I wish I had someone around here though that had one, I might have a play then...
 

Woody girl

Full Member
Mar 31, 2018
2,613
1,731
61
Exmoor
All the mention of toys after I warned against the risk of making a hasty purchase makes me think people misunderstood what I was saying.

People buy all sorts of things that are meant as tools so that they can tinker and play with them, without ever needing them to do real work. There is plenty of gear that we buy because it is shiny, looks interesting, and is shown in use by rugged adventurous types in far flung exciting places. The reality though is often that it doesn't really suit and after getting patted and ahh-ed over it gets put away and used little, maybe just because the opportunity to really work it was never there in the first place.

I also have a certain amount of concern about the creation of more plastic waste. Do we really need more plastic Christmas ornaments and funky flower vases? Yeah, some of the plastic is meant to biodegrade, but not all of it will do. Also, if you wanted a plastic pot or some sort of box, before your printer, you might have re-used a pill bottle or found some other item to re-use, whereas post-printer you can make a brand new item, maybe needing to make it more than once in order to get it right. This is a two edge sword, you can use printed parts to keep things going that would otherwise be thrown out, but other things may not be re-used because it is quicker or more fun to print brand new. 3D printing carries an appeal for the instant gratification gene.
I am trying to go plastic free. It's not easy as plastic is everywhere and in everything. We take it for granted and throw it away without thought. Trying to repair items is commendable and I'd like to see somewhere in each town where stuff could be repaired rather than thrown away. So in that respect a 3D printers would be useful. But nowadays I look for gear without plastic if at all possible. The next thing I think about is could I repair it myself if it broke. Or could I repurpose it in anyway. One simple change is wooden coathangers as at worst they are firewood when broken.. what can you do with a plastic one.? This was brought home to me when my plastic 10yr old spork broke and I needed a new one. The old one had to go in the bin as there was no possible use for it in any other way. I now have a metal one. It would be good if there was a way to reuse the plastic you throw away in the machine but sadly most plastic is sent to burn as it's not recyclable.
 

Woody girl

Full Member
Mar 31, 2018
2,613
1,731
61
Exmoor
Then there is the knotty problem of what to do with the plastic bit you are replacing... bin or what? Does it realy solve the problem of plastic waste or merely reduce it.... and every tiny bit of plastic you throw away gotta go somewhere . Into that lovely fresh cod and chips you fed your kids for supper last night?
 

Janne

Guest
Feb 10, 2016
12,368
2,257
Grand Cayman, Norway, Sweden
I am just as concerned and nerdy about plastic waste as most of us have become lately, but to be frank, it is not us that pollute the seas much.
Read something about 5 rivers polluting the seas most. One in Africa and the rest in Asia?
I do not recall 100%, it was a such depressing read.......
 
  • Like
Reactions: Woody girl

Woody girl

Full Member
Mar 31, 2018
2,613
1,731
61
Exmoor
Look in your bins! I put ALL my plastic waste in the recycling bin one week it all came back. It was an experiment to see how much they'd sort and take. So when I sorted it out properly 80% went into landfill rubbish bin.