Feedback request for upcoming FDM Quality Guidelines

[MadBuggyofDoom]

Hi all, newbie here, been lurking as I’ve got a cheap CTC machine I’ve had for a week and been playing with/upgrading, anyway, couldn’t resist weighing in on this one - I used to run a CNC mill for prototyping parts, and there’s no way in hell I’d agree to a 1% tolerance on most small plastic parts, especially ones made hot on the machine, even though I could hold far closer tolerances than that on the machine, why?
Well not only do you have shrinkage to deal with, but if the part relaxes over a few days whilst in shipping, absorbs some moisture whilst it’s sat in their workshop for a week, or you live in a place much colder/hotter than the customer, the plastic parts could have moved out of tolerance just through natural growth/reshaping. You could have a 1% change in dimensions just through normal room temperature water absorption rates alone on such as Nylon going from dry printed back to it’s more normal 2-6%

If you’re going to specify a 1% tolerance you really need to spec out whether that is relative or absolute, and at what temperature and humidity, and explain to the customers that their parts are going need to sit in a room with a controlled temperature and moisture level for a couple of days to stabilise so you can measure them accurately. Otherwise you’re going to have some real issues guaranteeing those tolerances on FF production parts which have all manner of internal stresses just from the way they’re formed, not to mention varying crystallinity not just from surface to interior but also on the filament skin to core. That’s not even taking into account any creep that might occur on the part later on depending on how and where it’s stored.

[Enza3D]

Thank you for articulating this so clearly, much better than I could have!

[PepCo_Parker]

Agreed. This brings up great points I hadn’t even thought about. It’s a shame it seems like it will just be ignored by the developers, I hope I’m not the only one who was even more upset to see that email rolled out completely ignoring our questions and concerns. Still a real lack of response on 3D hubs part.

[Perry_1]

It is really bad form to request feedback on a guidelines, then release the guidelines while still in discussion. It certainly sends a signal that 3dhubs is not listening. Especially when there are really a shortage of replies from 3dhubs for the things being discussed. It implies you asked for feedback to make the hubs FEEL like they have some input, but don’t really have input. With so many of your customers discussing it, and 3dhubs just implementing it during that discussion, it surely seems like you are not listening to your customers. I would like to remind 3dhubs that their customers are the 3d printers, NOT the folks that order the prints. Those are OUR customers. Many that we bring to 3dhubs on our own. Many of OUR customers ask us to work around 3dhubs, but I always push them TO 3dhubs, because the interface, software, and my payment protections are all worth the fee. But make no mistake, I am the 3dhubs customer, not MY customer, who ultimately gets the print.

Serious mistake here in handling your customers, asking for input while implementing the guidelines during the input phase.

I asked what the purpose of the new guideline are, and what problem they are trying to solve. This is key to me liking or not liking the guidelines.
I think the wording is still bad.
Several folks have asked for specific responses from 3dhubs in this discussion, and have not received it.
Folks are interested in how they handle ABS and Nylon prints, that can easily change size by over 1% due to shrinkage or humidity.
Several people asked how the guidelines might be enforced, and how the measuring could be verified.
Some folks stated they felt that they were not being listened to, and this was reinforced by a lack of response by 3dhubs to them.

All in all, I am for the new policy, but this is truly bad form, and a serious mishandling of the situation here by 3dhubs and their customers, in my humble opinion. I am all about increasing the quality of the 3d printing that is going on out there. I have customers who have brought me prints from other hubs, and I am shocked at some of the quality of the prints. So I am all for some better rules. That is not what I am talking about in this post.

It is hard for me to understand how during an ongoing discussion, 3dhubs could just go ahead and implement.

[Enza3D]

I think you and @Vienna3DPrint have hit the nail on the head. 3D Hubs has forgotten it’s role in all of this. The reality is my customers will come and go with me, especially if I discount 12.5% from my prices if they place orders outside of Hubs. Like you, I try to keep all my orders through 3D Hubs, with the very small exception of those who need to pay by other means (which is common with younger students). Hubs is supposed to be what Etsy is to their shops; Etsy just provides a site and a gateway, the shops do all the rest. Etsy does not own the customers, the shops do, and if the shops leave, so do the customers. It is very much the same here, but 3D Hubs seems to have forgotten that, or doesn’t care anymore because they got their funding.

Either way, the entire handling of this situation has left a very bad taste in my mouth, and I am very displeased to say the least.

[PepCo_Parker]

From what I’m reading here, it only strengthens my opinion on this as I see I’m not the only one operating this way. I too have requested to do deals outside 3D hubs but I push people to use it for its interface and organization. The way you guys put it is exact. The hubs are 3D hub’s customers, not the people buying parts! Unless they want to hire their own massive sales department to replace all us hubs I suggest they start listening. Until now I’ve not had reason to look into other platforms, and I’ve promoted 3D hubs a lot. This may incline me to look elsewhere to do business.

[Vienna3DPrint]

Hi

Well, that´s all a good intention, but poor execution. Why ? Because since now I was on the lower end of the price range. I could do that, because I have a full time job (that provides me and my family) and offer my 3D print services in my spare time. Therefore I asked my customers if they want to remove the support material themselves (to get the prints faster) or if I should do it (and they would have to wait a little longer). Often I didn´t even charge the support material for smaller prints. Only for bigger objects with a lot of support and time taken to remove it, I charged a small additional amount. You could say, the time spent for it was for free. Because average EU/US hourly rates for labour would be like twice to five times of the value of the print (guessed…)

It was good that the people could choose, because often they wanted (or had) to improve the print by sanding, painting or other methods. Now this choice is gone. And due to the nature of the producing machine (desktop home use) and method (FDM is the least accurate!) it will cause only disputes printing with non-dissolve-able support material. That makes it about impossible to use a single print head machine.

On the one hand it would be the logical next step for me to upgrade to a dual head machine. On the other hand it will make 3D prints MUCH more expensive for 3D hubs customers. Water dissolve-able support material costs 3-4 times of PLA filament. The dissolving takes about 12-24 hours (if I am correct). Higher and high priced hubs may print already that way and will keep their high price. But the possibility for cheap and fast prints (with customer removing the support) is gone with the change of guide lines.

That is NOT supporting the spread of 3D printing.

I don´t even want to speak about tolerances. It´s quite the same as with 2D prints. What kind of quality can you expect from a €/$ 50,- Printer ? People are then disappointed. Prints are not seamless, have wrong colors, are washed-out, a.s.o. You still have to invest at least 10-20 times more for a decent quality.

So, how can you expect extraordinary results from a €/$ 800,- 3D Printer ? (This average price is a guess. You might have better statistics).

A really awesome FDM print needs a CAD model that considers the abilities of the used 3D printer. It has to consider physical laws. The 3D printer has to be set up in terms of even and balanced print bed, correct space between needle and bed for the chosen resolution, prepared (sticky) print bed, correct temperature for the used filament. The slicer have to be tuned for optimal feed, speed, calculation of the g-code. The filament have to be of good quality. Maybe stored in costly ways (vacuumed). The print environment can have a big impact on the printed results (temperature control, humidity). And maybe more I haven´t considered here and now.

It makes the impression that DIY tools should reach top-professional high end industrial standards.

I don´t want to say that the aim doesn´t impress me, but now the vision has to meet reality.

It is not possible, for a reasonable price, to fulfill the announced standards. If you want the requirements to be met (seriously), then the hub must charge hours of pre processing with a lot of information transfer. Maybe some information is not even available because the customer has also only the stl file. Very often the stl is not water tight. So you need additional tools to repair it. Then, to finally meet the tolerance, a couple of prints (which blocks the machine naturally) to maybe recognise that the tolerance CAN NOT be met. And you can only tell after the support material is removed.

All that costs the hub time and money.

A small 10x10x10cm object could cost likely more then €/$ 250,- if requirements must be met.

This results in three bad things: High prices for FDM 3D prints. Less orders and revenue for hubs. Less profit for 3D hubs.

I would strongly suggest to not activate the guidelines for FDM by Jan. 5th, 2017. Rethink the role of 3D Hubs as a broker between clients and maker.

Refine the platform to be able to choose between instances of print quality. Collect and present possible print outcomes for customers. Not for hubs; they know them just too well.

Thank you and happy new year.

[cobnut]

Sorry @PepCo_Parker I wasn’t replying to your post.

[PepCo_Parker]

lol no worries I was just adding to your post

[cobnut]

@PepCo_Parker

I’ve actually got an interesting example of the dimension problem right now. The part has a shaft running through the middle and the part itself needs to fit tightly inside a tube, so both the inner and outer dimensions of the cylinder need to be spot on. The client has provided dimensions, but I’ve included what happened on printing (see attached).

Some of the dimensions are OK - the flange at 0.07mm too high is irrelevant for this model for example. The major issue is with the internal diameter that should be 15mm and prints at 14.4mm. I’ve corrected this in the model and it now looks OK, but what’s important here is that all of these dimensions of the printed part are within the 1%/1mm guidelines, even though as printed first time the print was effectively useless. (note, I know some of the dims don’t add up, I’ll put that down to variations in printing thickness and/or lack of coffee).

@Robin3D how should we deal with prints like this? Should we charge more for dimensional accuracy beyond the guidelines, how do we charge for modelling, measuring, testing, etc.?

[Vienna3DPrint]

Please just place somewhere in the guidelines: All services are based on best effort by the printing hubs.

That will not put an end to complains, but release the pressure from hubs and puts everybody on the safe side.

Thank you

[Q_Scott_Kaye]

There should be an option for the customer to select removal of support material or not and have it priced upfront. Also, support material needs to be factored in the price at the start as often times I have parts that have more support material than part material! Finally, customers who choose to print at 200 microns for cost reasons seem to expect 100 micron resolution and may complain.

Maybe there should be two tiers here. Professional hubs with$10K plus printers who can produce professional results and charge for it and Hobby Hubs with Hobby level machines that produce good quality but not at the level of the Pro hubs and charge appropriate prices.

[PlastiPrint3D]

Unfortunately the price of a printer rarely gives an indication of the quality of the print. I have seen prints come off 100k machines that are good for nothing but the bin and incredible prints come off a well tuned £300 printer.

Unrealistic customer expectations is another wonderful discussion point. Unfortunately with the perception of 3D printing in the wider world that it can do anything and is instantaneous it’s a real issue to bring home the reality to a customer.

[Sean_Houlihane]

I understand that its important to provide a consistent expectation, and maybe the solution is to agree deviations from the spec in advance, but I feel this adds unncessary cost to some parts.

I recently printed a structural part (to hold a lens) which has a 5cm long un-supported beam. With a support grid at 5mm intervals, this printed fine using PLA on a cheap FDM printer (as evidenced by a repeat order). I don’t think I’m able to print flat overhangs to the specified quality, even if I used 100% support - and there is a risk that aiming for a directionally consistent print will lead to poor orientation choices.

[Robin3D]

@PlastiPrint3D @rkelly @John3d @PepCo_Parker @Enza3D @cobnut @Perry_1

Hey guys,

First of all, Happy New Years! I hope you all had a great holiday period. My apologies for the delay in my response, I also had some time away from 3D Hubs and 3D printing because I was spending time with my loved ones.

I can tell this topic is quickly going into the direction which we feared already when we started this entire project. I can completely understand that these guidelines can come across as intimidating but please understand that they are not meant as such. The reason why we started this project to begin with is because me and my fellow admins came across orders where the quality of prints that were delivered to customers were far below what the average Hub prints creating a terrible experience for customer and giving FDM printing a bad name. The FDM guidelines have been created to set reasonable expectations for both Hubs and customers.

From the very start of this project we set out to create guidelines in co-operation with our Hubs. That’s why I created this thread 2 months ago before any guidelines were created: Talk Manufacturing | Hubs.

Afterwards, we created a first draft that we send out to a first selection of Hubs and asked them to give their feedback/suggestions directly on the Google Document we created. Once we took all their feedback we created the version that you see now in this thread. After a week I saw almost nothing but positive responses and we went ahead with the implementation of the guidelines which will go live in a couple of days.

Now, the main issue that I see is the topic of the dimensional accuracy. I am still completely open to suggestion on how we can formulate this differently. The guidelines are not set in stone and if we see something is not working as intended, we can change it.

Please know that I am reading everything you guys have to say and I really appreciate all your input. I hope that I’m correct when I say that your concerns show me that you care about 3D Hubs and what happens to this platform.

If you have any additional concerns about 3D Hubs as a whole, you can always reach me through robin@3dhubs.com

Best,
Robin - 3D Hubs

[Robin3D]

@Perry_1 I hear you, what exactly feel uncomfortable to you? And do you perhaps have an idea how we can tackle this for you?

[PlastiPrint3D]

Here’s a simple idea, make the guidelines optional. Rather than forcing hubs to abide by them, allow hubs to opt in or out similar to the student discount option. Have another badge or make it a searchable option for customers.

My issue with this and some other things that 3D hubs does is that there is no way to opt out. It’s forced upon us which instantly puts me on the defensive.

[Sean_Houlihane]

One reason that ther may have been a delay in feedback is that people might have read the guidelines, and felt they had an interpretation which made sense - then later came here to read the detail (or made a print for a specific purpose) and realise that the context can have a big impact on exactly how the guidelines are interpreted.

Sure, use these guidelines as a benchmark, and require a hub to agree to deviate. Under the guidelines, this part Dial Gauge holder for Anet A8 by tsh2 - Thingiverse is impossible for me to make. See the surface where support was removed on the square at the bottom, all untidy, but quite functional. It didn’t occur to me on first reading of the guidelines that you intended to block me from offering parts like this.

[Vienna3DPrint]

Hi Robin

Do not reduce it to the accuracy. The mandatory removal of the support is another unsolved issue.

Until now I charged either nothing for it, because the object was small and easy to remove, or for support material as it was like 50% of the print, or both: support and removal. Sometimes the customer wanted to remove the support himself.

What now, if the customer wants to remove the support himself ? (To safe money)

It´s quite unfair to raise the overall price, because that affects support free prints also.

Should the hubs, regardless from the wishes of the customer, charge the removal of support (and remove the support anyway) ?

I also just removed the support. I did not tweak the print. Some objects are just crazy ! On big objects it really took several hours just to basically remove the support. With sanding and what so ever finishing this process may take days.

Which customer is willing to pay for it mandatory ?! Well, some want the support removed, but others not.

And as mentioned before: This guideline will make it very hard for single head printer hubs to continue to print with support.

3D hubs may improve the overall quality, but also raises the overall price for 3D prints.

bye, Tibor

[JothamB]

I have no issue with setting standards for surface finish and supports and such. What does concern me however is how tolerances are set so high that even ABS plastic shrinkage could potentially put my part out of tolerance.

+1 on optional dimensional tolerances with a searchable badge

+1 on setting standards for surface finish and removal of support structures.