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How to deal with the proliferation of 3d printed nonsense?

BoxcarPete

Stainless
Joined
Nov 30, 2018
Location
Michigan, USA
Worst offender I ever saw was a 3D printed vise. Pictures actually looked pretty nice, until you started noticing details like the 60° threadform instead of ACME like every load-carrying lead screw for the last 120+ years. If he did the 60° profile to avoid using support between threads, that's even worse: it means the deposition layers are in the axial direction. Congratulations! You've designed the primary load-bearing member of your assembly as an anisotropic column with its weakest direction directly along the load-carrying axis!

Edit to add: That is just the worst example I've seen. Most people who are dinking around with printers don't sufficiently understand the mechanics of the end result enough to design around its shortcomings. Those people produce junk as a result, even if they bother to clean it up.
 

Garwood

Diamond
Joined
Oct 10, 2009
Location
Oregon
In the spirit of this thread I should mention that about a year ago I bought some small 3D printed replacement parts from an ebay vendor. The seller's photos of the items looked pretty good so I decided to buy them. When I opened the package I found misshapen blobs that barely resembled what was advertised. The seller refused a return (by trying to ignore me) so I opened a dispute. I eventually got my money back but it took persistence.

In my view part of accepting 3D printed stuff as a valid source means taking a hard line with the chiselers who sell junk. A lot of people see it strictly from a financial point of view and would rather just chalk it up to experience than waste valuable time fighting these crooks. I view fighting them as not only community service but also as an investment against future cheats.

I think we can agree on that. And that's part of my frustration. There's this kind of overwhelming support and lots of leeway for people 3D printing products for sale and nobody that I'm aware of making real stuff gets that kind of pass.

I have seen some pretty nice pro printed casting patterns. I don't see much of any nice looking products sold by these ecommerce 3D printing small businesses. It all looks rather shitty to me.

Maybe I need to lower my standards. You know, blaze around parts with a 2" indexable and .250 stepover, drill all the holes 1/16" oversize or just use the same drill for everything. I could make junk and people would probably buy it, many of them not knowing a difference if it fit and could be sanded to look OK.

Why should the 3D print folks never be called out when they make stuff that looks like shit?

It's not a hobby when you are selling it for a profit.

Is there a surface finish gauge for 3D printing like we use for metal? Is that a thing? If it isn't maybe it should be.
 

M.B. Naegle

Titanium
Joined
Feb 7, 2011
Location
Conroe, TX USA
We've talked about getting a printer in our shop for a little while. I think it helps to keep up with innovations, even if the first renditions are rough, but don't jump full in with both feet unless it's best for your product and your customer.

A lot of the product we make is old school castings and mild steel parts, because that's what they had at the time these machines were new. In the last 20 years we've changed a lot of parts to be made out of tool steels instead as they of course last longer, but with that innovation we've also considered the effects of those hardened parts on their surroundings. Do we want a $20 indestructible shaft to wear out a $2000 cast frame?

Some parts we're considering printing are complex shaped fluid reservoirs that were in the past made from cast bronze, iron, or aluminum, and they've always been prone to corrosion (water based fluids inside), so for the last 10-15 years we've made them from stainless stock welded together. Works perfect and never corrodes, but it looks terrible seeing this weldment thing compared to the curvy castings of the rest of the machine. The optimal solution would be to cast them from stainless, which is still an option though it would be more expensive (less manual labor than the welded ones though), or we might try printing them from plastic. My concern though is how many of our customers would see this pretty plastic piece on our machine that used to be metal, and think we're cutting corners, even though it's actually more of an improvement, So in the end you have to look at it as a complete package. Like the posts above about parts that are never seen or customers that don't care, you have to consider the overall image and reputation of your product.
 

William Payne

Aluminum
Joined
May 29, 2016
Having read all the posts I must say the people buying and making cheap basic 3d printed parts are probably not the customers most people want anyway if you are in the manufacturing business.

There are legitimate good uses for 3d printed plastic parts, someone has mentioned patterns and such.

Anyone making plastic parts in high volume is injection moulding them. 3D printing is as slow as a snail in comparison but has an entry cost within reach of the average person.

Metal sintering however is absolutely a viable means of production as there are things you can do with that that you just can’t otherwise easily do.
 

Bill D

Diamond
Joined
Apr 1, 2004
Location
Modesto, CA USA
A re-run episode of Counting Cars, there is a choice between 3d printed red tail light lens and the originals.
It would cost $100 to make two 3d copies.
It would cost $1000 for two original pieces.

The Count went with originals.
I. think i saw that and I feel he made mistake. He got aged parts that may be brittle vs newly made stuff of modern plastic. This assumes the new stuff is made of good approxiate plastic.
If this was a 1970's Volvo amber turn signal lens it would a no brainer go with modern plastic that hopefully will not fade to clear in the sun.
Bill D
 

triumph406

Titanium
Joined
Sep 14, 2008
Location
ca
. The optimal solution would be to cast them from stainless, which is still an option though it would be more expensive (less manual labor than the welded ones though), or we might try printing them from plastic.

You could print the part from one of the filaments made for wax investment casting. Give it too a wax investment caster to make a part using the 3D print to replace what would have been the wax in the past.

Of course not likely to be cheap, but by 3D printing the wax you could add some interesting shape to the part
 

dgfoster

Diamond
Joined
Jun 14, 2008
Location
Bellingham, WA
We've talked about getting a printer in our shop for a little while. I think it helps to keep up with innovations, even if the first renditions are rough, but don't jump full in with both feet unless it's best for your product and your customer.

A lot of the product we make is old school castings and mild steel parts, because that's what they had at the time these machines were new. In the last 20 years we've changed a lot of parts to be made out of tool steels instead as they of course last longer, but with that innovation we've also considered the effects of those hardened parts on their surroundings. Do we want a $20 indestructible shaft to wear out a $2000 cast frame?

Some parts we're considering printing are complex shaped fluid reservoirs that were in the past made from cast bronze, iron, or aluminum, and they've always been prone to corrosion (water based fluids inside), so for the last 10-15 years we've made them from stainless stock welded together. Works perfect and never corrodes, but it looks terrible seeing this weldment thing compared to the curvy castings of the rest of the machine. The optimal solution would be to cast them from stainless, which is still an option though it would be more expensive (less manual labor than the welded ones though), or we might try printing them from plastic. My concern though is how many of our customers would see this pretty plastic piece on our machine that used to be metal, and think we're cutting corners, even though it's actually more of an improvement, So in the end you have to look at it as a complete package. Like the posts above about parts that are never seen or customers that don't care, you have to consider the overall image and reputation of your product.
The solution to the conundrum of classic heavy metal vs plastic for your, in my opinion, very cool sewing machines may be found by the customer. Make up one fabricated stainless reservoir and twenty plastic printed ones which can easily include the machine logo visible to the user. Price them fairly based on your cost. I'm thinkin that SS one will be on your shelves for a while.

Easy to make up some new SS ones, if I'm wrong. Either way that printer will get use. For a basic but very serviceable first printer I would highly recommend the Prusa over the Ender or the myriad of "Off Shore" knock-offs. The difference is the Prusa works out of the box, is unusually well supported by user groups, extensive online documentation, and live chat help provided by folks who speak English as their first language, and will, based on track record, continue to be supported with very reasonably priced upgrade kits as this open-source printed continues to improve and evolve. A comparable knock-off with what looks on paper like it has the same work envelope and print speed will cost 300 less. But, you're largely on your own now and in the future....

Denis
 

turnworks

Cast Iron
Joined
Dec 12, 2018
I think the 3d printing has just given more tools into an engineer's toolbox. Or maybe it has opened up the box they have to design within thinking of if it can be made.

Might be way off.
 

rons

Diamond
Joined
Mar 5, 2009
Location
California, USA
I. think i saw that and I feel he made mistake. He got aged parts that may be brittle vs newly made stuff of modern plastic. This assumes the new stuff is made of good approxiate plastic.
If this was a 1970's Volvo amber turn signal lens it would a no brainer go with modern plastic that hopefully will not fade to clear in the sun.
Bill D
He didn't make a mistake because his reputation is on the build of the car. And the plastic parts are new old stock in perfect condition.
 

edwin dirnbeck

Hot Rolled
Joined
Oct 24, 2013
Location
st,louis mo
I'm becoming disgruntled at the proliferation and general acceptance of 3d printed low volume retail products.

I appreciate, respect and compliment the concepts and creative uses of materials. But I'm really struggling to bite my tongue with full grown adults marketing products that look like god awful shit and people actually buying the stuff.

I feel like it's an erosion of craftsmanship when things that could be made very nicely and affordably through any number of manufacturing processes are 3d printed, look like cheap fuck and folks actually by into it and support that.

Am I out of line with this?
Traditional die cast plastic and metal "stuctural" parts are ugly AND loose half of their strength because one side is allways open,exposind the ribs. IN THE NEAR FUTURE,designers will be able to design MASS PRODUED PRINTED PARTS.The parts will be made to funtion,with no consideration given to parting lines, core pins. ejecter pins ,sand cores , or "how you gonna machine that". Parts will have STRAIGHT walls, real hollow cavities ect. This will happen.Edwin Dirnbeck
 

dgfoster

Diamond
Joined
Jun 14, 2008
Location
Bellingham, WA
This thread began with complaints about crappy printed parts. And earlier in the thread I pointed out that the person printing a part can, if they understand the material and printer settings, greatly affect the quality of the printed part. For instance, polycarbonate filament, though a bit tricky to print, allows printing parts able to withstand impact and bending forces better than same part made with the ubiquitous PLA filament. And ABS withstands UV better. And printer settings have a big influence on print quality (and print time).

Here are two PLA prints of the same part made on the same printer but with settings changed to optimize print time and also differences in how the print was supported using printed "scapholding" to better advantage in one case vs the other. Much like machining a steel part, alloy and machine settings make a big difference in the end result.

Top surface of low resolution print
Printed lower es1.JPG

Under surface low res print
Printed lower res.JPG

Top surface of higher resolution print
Printed higher res1.JPG

Under surface of higher resolution print.
Printed higher res.JPG

The higher resolution print takes twice as long to print as the lower resolution one. If the vendor is into pumping out parts as fast as possible without regard to surface finish, which settings is he likely to make?

Denis
 

whateg0

Aluminum
Joined
Mar 24, 2009
Location
Wichita, KS
Seems that a lot of focus is on FDM parts/items. The surface of the stuff I print on the Mars or Saturn is wonderful. Not perfect but way better than any FDM stuff. We still use the ender 3 for a lot of stuff but anything with intricate details gets printed on a SLA.
 

michiganbuck

Diamond
Joined
Jun 28, 2012
Location
Mt Clemens, Michigan 48035
there are things that can only be 3d printed.
I think there is a future for 3-D printing, and have a stock position in Vjet. (voxeljet AG) a German outfoir in 3-d printing.
 
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Strostkovy

Stainless
Joined
Oct 29, 2017
If it's just the poor quality that bothers you, go look at a metal fence or a school desk chair. The welds are dog shit, but people don't notice or care. Same with soldering in consumer products.
 








 
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