Black High Definition Acrylate For Sale To Shoppers / Updated Guidelines

Its finally time, you can now set Black High Definition Acrylate for sale! Hurray!

Before you do, check out blog post announcement here, and the updates to the Guidelines here.

New Guidelines are:

0.7 mm thick and supported wires should be a minimum of 0.8 mm thick for wires less than 35 mm in length.

We recommend making your wires 0.1 mm thicker for every additional 20 mm in length over 35 mm to ensure we can post process it without breakage.

Walls under 5 mm in length should be a minimum of 0.5 mm thick. For every additional 20 mm in length over 5 mm, we recommend making supported walls 0.2 mm thicker and unsupported walls 0.25 mm thicker.

For hollow models we added a requirement of at least 2 escape holes with a minimum diameter of 6 mm each per interior cavity.


Questions? Comments? Product photos of what you'll sell? Fire away!


Final note: we're gearing up for the shopper facing BHDA launch in a few weeks. Right now this announcement just targets shopowners, so don't stress but so this is a great opportunity to get your shop ready and let us know what you'll be offering so you can be part of the gift guide

The guidelines seems somewhat crazy for me.

+ 0,2 mm for each 20 mm length?
Even quite small H0 train model is around 20 cm long => 2,5 mm wall thickness?
The same in N 1,5 mm wall thickness?

Competition is ok with 1 mm thickness in any length of wall.

Everything over 1 mm is too much for hollow fine scale models ...
I hoped for compatibility with FUD/FXD, this is not very usable for me.

Hey @czhunter these are recommendations based on what will eliminate the warping of some geometries. Not all models warp but when they do its often due to insufficient wall thickness.

Feel free to make your models 1mm thick for now but overall, the larger your model, consider making them thicker to prevent warping.

Great news.
Acrylate will force me to use variants for pWSF and Acrylate. Any recommendation how that can be achieved best?

Hey @woody64 thanks!

can you give me an example? that could probably be something we could add if its just a Variant type: material, Variant options: BHDA, WSF type of thing

I have to make variants for WSF and BHDA since it have different design ruels. In princible that maybe a Topic that for materials which have different design rules you may Need a variant (i.e. wall size, sprue size, ....)

How much more in cost will it be to compared to WSF?

All my models were rejected during the pilot phase. Is there any reason to hope that this has changed, or are those of us with sprues and undercuts still pretty much screwed?

https://www.shapeways.com/model/upload-and-buy/4794657
https://www.shapeways.com/model/upload-and-buy/1395548

These two items are designed for different materials.

Woody64

@Andrewsimonthomas: I'm confused. We've always had the ability to upload a model and allow it to be ordered in a variety of materials. What Woody is very astutely getting at is that the rules for designing in BHDA are so dramatically different than for the other plastics and resins that you really can't use one for the other. It gets to be even worse if the SW techs are screwing around with our models by canting them at bizarre angles; I had a model rejected last spring because it was four parts connected by a sprue, even though the sprue and all four parts were designed to sit flat on the print bed, alleviating the need for support columns. That still wasn't good enough, apparently.

So far, I haven't seen anywhere that SW has addressed the problems and shortcomings with BHDA that were brought up in the pilot thread last spring. Not that any of my items will ever likely be printable in BHDA, but it would be nice to know that SW was listening and at least trying to resolve some of those problems.

I has also to fight with rejections (due to the placement of sprues). I need 7 iterations to find the actual solution (hoping that it holds now, otherwise I have lost a lot of time, money, a blender script explicitly written to generate this sprues and the chance to improve sells with this promising material ). The real pity was, that none of the SW engineers was able to help taking a look on the production need for this material AND on the item need (where can the sprue be placed without damaging the item after cutting). I simple had to guess what the problem may be. The type of connection I'm using now must have been also seen by somebody from the team familiar with the production process, the material needs and looking on the item what's possible and what's not.
I'm really horrified that after some time once more a rejection cycle starts destroying all the efforts I've put in.
(I think for pWSF I had to change it 3-4 times. Imagine what sort of fun that is for more then 100 items. And how many rejections and lost of sales I had before I was able to exchange the majority of the supporting sprues to the actual guilty design lines)

Maybe I'm not the target since my sales are to small (based on item size). But please SW help your shop owners sorting such kinds of questions out in both interests (decreasing the production costs for SW and designers and increasing the sales for both).
Means: address the shop owners which were interested in this material and have a certain quantity of sales which are interesting for you and tell them exactly what they have to change that production works best and is in-line with the item needs!!!! (see all the rules/experiences shown at the begin of the post)

Comparing to WSF does not really make sense - it is going to be somewhat more expensive than FUD on average I would guess (slightly cheaper per ccm, but parts need to be thicker) and you get all the fun of solid break-away support stalks under overhangs etc. that the powder sintering or multijet acrylics processes did away with. (Even the industry-grade Stratasys FDM printers seem to be using a dissolvable support material nowadays)

@javelin98 @woody64 I think we have to look at this material (and some others as well) a little differently than we have in the past.

Our goal is to make this material, as it is, the best that it can be. When we're approaching the guidelines we want to give clear and specific ideas on what we're confident we can produce, what we're confident won't be rejected or what won't have quality issues down the line. Those guidelines may mean that not every model can be produced in this material, and thats okay right now. We want to be able to make the models we can produce really well.

Once we're up full speed on the material we can look back and see what we need to optimize for next. In both your cases, thats batches of parts attached by sprues. That might require a totally different solution than DLP processes and we should consider it from that perspective. lets not try to fit square pegs in circle holes.

Andrewsimonthomas >

I think this aproach - that not all materials are suitable for everything, and some materials are suitable maybe only for very small amount of projects - is understandable.

But then you have to change the pics on material page for better understand what is this material good for, and what not.
From four pictures, i guess two are according new guidelines unprintable (forklift and loco - and what is worse, they are basically "made of sprues" - the kind of model you don't like) one is not suitable (iPhone case - for that size you would nee quite big wall thickness an you get fatPhone in the end) and just the astronaut is the type of model, that is this material very suitable for.

Maybe such an easy explanation dumb modellers like me need to see.

Great news!

I've retired the detail plastics in my shop and replaced them with the bhda versions.

Hurraaa: it seems that the item is gone to product stage and on the way to the customer (although having connectors). I'm excited to hear what the reaction there will be.

Hello,

Did I mis something? Several shop owners, including RAILNSCALE, have been testing this B-HDA material with very different outcomes. We had one vehicle printed three times. Each individual print appeared different. See here: https://www.shapeways.com/forum/t/new-material-black-high-definition-acrylate.39421/page-11

The results are so far not conclusive. Several questions were raised to SW. What kind of print quality can be expected? What can I tell my customers what to expect? How big are the expected deviations? And in which cases do we talk about a misprint?

Below you find our findings, based on the 3 prints. Which of these findings are confirmed?

1. Potentially B-HDA has a very smooth surface quality that matches the surface quality of injection moulded parts. However the other print shows almost as much sharp edges as FUD. Appearently the printing proces shows a lot of deviations. So, it should be a plus. But not always! The inconsistiancy in print quality is a big concern;

Question 1: What surface quality will SW guarantee?
1A. Entirely smooth without ripples
1B. Anything between the extremes we've seen can happen and are part of the proces

2. We mentioned that B-HDA does not require elaborate cleaning. The second print however was sticky. Not sure whether this model can be painted properly;

Question 2: I assume the sticky surface was a result of improper UV curing. Will SW guarantee sticky free surfaces?
2A. Yes, all B-HDA prints will be free from sticky surfaces
2B. Anything between the extremes we've seen

3. For painting purposes a brighter colour (white, bright gray) would be welcomed;

Question 3: Will other colours become available?
3A. Yes
3B. No
3C. Maybe in future

4. The dimensional quality of FUD is better. All B-HDA parts were warped, in different ways. Warpages seem to be a B-HDA feature.

Question 4: Will geometries that are in agree with the design guidelines be free of warpages?
4A. Yes
4B. No, this is part of the printing proces. So basically designs that made out of multiple parts that should have a tigtht fit are not suitable designs.

5. B-HDA does require the removal of support material with knives. This removal is not only labour (cost) but adds inconsistency and damaging of the B-HDA parts.

Question 5: What does SW consider acceptable manual damages?
5A. If a customer complains, he will allways be refunded
5B. Cutting damages are part of the proces. These imperfections cannot be avoided.

All 'A' options would mean that B-HDA will make it to our shop too.

I'm looking forward to your answers.

Regards,
Maurice
RAILNSCALE

Expecting the first customer feedback very soon ....

Do you have any proposals how to deal with different design caused by material design guidelines via variants?

one of my customers received the first batch, but he reports problems with the fitting. Which means that the inner ring is to tight (he has worked with the knife to put it on the heads but you see that the helmets are sitting to high).
That means that there is a scale problem which was also discussed during prototyping. How is your advice on that and what shall I say to the customer?

Hello Woody,

Well you show what we consider the real problem with this nice apperaing Black HDA: the geometrical tolerances are not good compared to FUD/FXD.
The 3 prints we had showed all different sort of defects. That's why we -although the material looks so nice (sometimes!) - are not prepared to offer our products in this material yet. We really do not want to go into the direction where our customers have to be the guinea pigs. It will quickly result in a bad name for us.

That's why we've raised the stated questions above. SW so far did not answer these yet. Which is a bit surprising, because I think they really want to push this material.

Regards,
Maurice & Joris
RAILNSCALE