No more un-supported parts. Thinner walls and wires for everyone. FD & FUD

This is my first post on the forum, but I have been pulling my hair out with several designs, trying to meet the print guide lines, while still maintaining detail and accuracy using FD and FUD
If I am correct, and if the process could be approved I think everyone could be a winner.
What I am suggesting is that in a situation such as in this picture,



there are several problems.

Complexety of the sprue. Time involved in design and checking.
Which also adds to the file size.
Sprue being larger than the part/ wire it supports.
Sprue removal by the customer, risking damage to the part.
Wasted material.
Low density packing of parts.

If I understand the process correctly, the completed piece would then be heated to remove the support wax.
Re-packaged at considerable expense in materials and transportation charges. In a container considerably larger than the part and surrounded with foam pellets, to withstand the possible g force loadings, and other handling damage.

Would it not be more sensible, to do away with the sprue entirely.
Group the pieces more closely together and then surround the parts in a printed container. Printed at the same time as the parts.

This time leave the support wax in place inside the printed container. Pop it in a jiffy bag and send it off.
Although the container adds to the cost.

The advantages are we can print smaller more detailed parts.

I would think virtually zero damage to parts while handling or transport. All the other arguments against thin walls and wires.
Substantially reduced packaging and transportation costs.
The customer bears the cost of heating the part to remove the wax. This is if the container can be separated from the print run before usual heating/ wax removal stage. If this is not possible it does not become a problem as the parts become consolidated again when cool when you leave the wax in.
The customer no longer risks damaging the smaller parts while removing them from the sprue. Simply heating and cleaning the parts as normal before post processing.

The cost of the printed container is largely offset by the removal of the sprue, and the other added benefits far out way it.
Plus you get a free box and some candle wax.

Does this seem feasible.
I would think a simple tick box should do it. "Wax on / Wax off".

Naturally the container forms part of the customers upload.

Here is one I made earlier, before it occurred to me to remove the sprue.

I am slightly confused as to what you're asking for. Do you desire to have the container be free?

You already can accomplish exactly what you're asking for.. simply put a closure on the front of the box that the customer has to clip open, and put a 2x4mm drain hole in the bottom.. They'll get the whole assembly.

Now, if you're asking for the container to be free.. that is a decision for Shapeways to make, but because of the amount of material consumed, I bet it won't happen.,

I'm sorry you miss understood my little joke. Obviously the customer pays for the container, which is actually useful after you have received the parts, rather than the short sections of chopped up sprue.

Absolutely do you not want a drain hole in, as the whole point of my suggestion is for the wax support to act as the protective medium during handling and transport.

And so considerably reducing the cost in production, packaging, transportation, damage, and customer breakage.
Also removing the restriction applying to unsupported parts.

Does this make sense.

It also allows a greater packed density.

You simply let the customer gently heat the container in hot water until the parts can be removed. Followed by the usual wax residue cleanup by ultra sonic bath or however.

The extra cost to the customer for the box is negligible due to the greater packed density. The volume of the box being not much greater than the original sprue. But as the parts are supported at all times until they reach the customer by the wax, there is no need for the extra thickness on, what were unsupported parts wires, and walls. The supported minimum thickness can be used thought out. There is no need for the customer to cut often thin parts from equally strong or even stronger sections of sprue where breakage can occur.
The cost savings to Shapeways in packaging and transportation should obvious. Even the possibility of one less operation, and reduced energy usage.

I had thought of Shapeways supplying standard or custom sized containers of the most suitable/cheapest material, at the customers expense, but transfering the part after printing is basically where you are now, and loses the advantage of the part being supported at all times.
As you can see from the pictures, I had origionaly considered paying Shapeways to package my prints in custom injection formed cycle puncture repair type boxes. Same problems as above.
KISS.

I think you could do this already, if you really wanted to... For at least FUD - not sure about FD - creating a very small, basically non-functioning "escape hole" is allowed, as the trapped opaque wax can be used for skeleton-like effects with the transparent
acrylics. The drawbacks as I see them - nobody at shapeways could check if the parts were printed correctly,. the customer would
have to pay for the box as well - which would probably need rather thick walls to be useful, somebody would have to pay for the non-trivial amount of wax used up, parcels would probably be noticably heavier, and shipping would probably become very messy
if the wax gets any chance to melt and ooze out.

Hi. all very good points. I had all ready realized that it would be impossible to check the contents inside the box. Only Shapeways knows what percentage are bad prints, and I would guess any print errors would show on the box as well.

As for thick walls, I would think the opposite would be true, as the wax would not only support the parts inside the box, but also the box walls.
You mentiond seepage, and I think I remember a temperature for the inside of cargo holds being stated some where. Is this above melting point for the wax. If so, then I would suggest that the box is printed totally sealed with an indentation to run an opener/craft knife around.

It would be simple for Shapeways to issue a scalable template to the required spec the same as in wall and wire thickness requirements.
I have no idea what the cost of the wax support material is, or whether it is an expensive formula, but I suspect it is relatively cheap in comparison to the plastic/acrylic feed stock. In the volumes I am thinking, the weight would be trivial as well, and certainly less than the currently used card board packaging.
I think the customer would be willing to pay the slightly higher prices for the convenience, and extra accuracy.

Going back to the first point, I would not have thought that the print run requires an operator by the machine at all times. Do you have anything like video recording of the print for any future disputes or error checking.

I still think it appears to kill a lot of birds very easily. But I am very new to this tech, although I have many years experience in manufacturing and design.

I'm sorry that I seem to have missed the point about the "non-functioning escape hole". Is this required for thermal expansion, or possibly unpressurized cargo holds.
Is there a land or sea route.

Following on from this, the next logical step is to remove the stacking/placement of the objects inside the container, from the customer. This can obviously be automated, and I expect you already use a similar scaled up version to arrange your print runs anyway.
This would ensure maximum density of packing.
Minimum support wax required.
Minimum size surrounding container.
Minimize errors in overlaps.
Maximizes machine output.
Minimize energy usage.

Simply upload the collection of parts "file" separated. Let software arrange the islands/ shells, tetris wise.

As I mentioned earlier, another major factor would be the reduced packaging. This should also offset the increased cost of wax and surround.

The "non-functioning escape hole" is just the usual hole in the surface of hollow parts that is required for them to be actually treated as
hollow by shapeways' software - just that for FUD it can be so small that it does not actually allow removal of the support material.
So nothing to do with shipping, just a construction trick to get a hollow part with the support wax still inside.

With print runs taking something like 24 hours at least for some of the materials, I doubt they actually keep an eye on their printers all night long - nor would anyone review any full-length cctv coverage just to check if every single print layer landed where it belonged I guess. So much easier to just look at the finished pieces unless people start taking your advice to order everything in aspic.

Have you checked yet what just your typical container alone would cost in FUD ?

Hi, yes I have been trying to think of ways to not only improve the product, but reduce the cost all round.
I have just received my order for 50 1/72 hand rails, conventionally sprued, in SWF. They are excellent, and while this is the wrong material for this process, the actual size of the complete sprue was half the size of a small match box. It arrived in packaging half the size of a shoe box.
If this had been in FUD, and I omitted the sprue, the printed container could have been half, possibly a quarter this size again. Also avoiding the necessity to accurately cut, and re trim from the sprue.
I understand now what the non functioning hole is for. This must be a very simple task to inform the software that the container is in fact hollow, and not a solid object. But until then I noticed that Shapeways put the print in a sealed plastic bag in any case, If it did happen to ooze a bit.

I had hoped for an official response from Shapeways, by now, as I have customers waiting to purchase my kits.
It is very frustrating to have parts rejected at the printing stage, dispite getting through the automated checks.
Also having to constantly increase the thickness of parts when as you can see from my pictures in the shop they have been successfully printed in the past.
I presume the arguments for thin sections are the difficulty in handling the parts while removing the wax, and in packaging prior to shipment.
This method avoids all of those problems, and the parts are protected during transport encased in the wax matrix. Making damage almost impossible until the point where the whole container is crushed. A simple "jiffy" type bag should suffice vastly reducing shipping costs, also impact on the environment.
This method helps to make the process competitive with injection molding, and resin manufacture, while approaching photo etch for level of detail in some areas.
As a quick test, I took my original sprued kit, and removed the spure, rearranging the parts and encapsulating in a box with the non-functioning hole.



Volume 2.12 cm3.



Volume 2.12 cm3. using minimum supported wall thickness for the box.

As you can see, I'm not very good at tetris, and there are large voids which could be reduced by spending more time arranging the parts. Or better still automating the process.
Beating the original volume.
If I increase the box wall thickness to 0.6, despite the fact that the walls are not unsupported, the volume becomes 2.73 cm3. Adding 2 dollars to the cost, while reducing the postage and packaging by as much as 8 or 10 dollars.
Could we have some thoughts from Shapeways.

I know one argument against this would be the possibility of damage while the customer is trying to open the box, perhaps cutting through and damaging the parts inside. This is a simple design problem, and the one that springs to mind is the method of opening a can of beans without a can opener.
Have a raised lip like a tin can, and remove the lip by rubbing on a flat piece of sandpaper until the whole lid is detached. No need for a knife.
As for the aspic argument. The parts are not delivered totally clean, and they always need further cleaning to remove the residue wax, so this is no more of a problem in reality to the customer than now.
As for not monitoring the print process. With the cost of data storage what it is, and a simple cctv setup, and the ability to simply type in the time stamp, this is another non problem, although it does add to overheads, so may not be deemed worthwhile.

It does seem to me nonsensical, to use time and energy applying a support material. Using more time and energy removing this support material.
Replacing it using more time and energy, to replace it with a far less efficient and costly support material.
Go figure, Kiss.

And so on to the final problem. How to identify several similarly sized and shaped boxes separated at the end of the print run when the contents cant be seen.
As you can see, I have created a range of name plates. My original intention was to include these attached to the sprue to enable ease of handling during post pro.
All that is needed is an ID printed on the out side of the box. Whether this can be left to the designer, or applied by Shapeways I don't know.
It could be included in the specs for the template I suggested earlier.

I see that this whole method would actually simplify if not remove 3 production stages, and while radical, and counter intuitive, seems to me to be the way forward.

I understand that I could already order the kit like this as it stands, but would probably still face the restrictive minimum unsupported wall and wire thickness limitations, where this problem no longer exists, and still receive the order in half a shoebox.

I do hope we can all win here.

ps, I did mention impact on the environment.

Bogey, Eco Design.

I'd say try to order this, and see how it goes. As far as the parcel size is concerned, it probably does not make sense for shapeways to keep tens of different boxes in stock just to have an optimal solution for anything from matchbox to furniture. (Shipping may even impose a lower limit on parcel size for
efficiency). And environmental impact of your proposed solution may even be worse if it has individual customers disposing of wax instead of a single industrial facility that actually recovers a large fraction of this support material for reuse (and probably has more elaborate disposal procedures in place
for the remainder than just pouring it down the drain)

I totally agree that Shapeways probable keep a small range of box sizes.
I am also talking about FD and FUD.
How large are most parts ordered in those materials.
This gives the option for Shapeways to use padded envelopes instead.
In the range of 50 orders delivered in the space previously taken by one.
There is the fact that the average customer wont have the same facilities to recycle the wax that Shapeways has.
Factored against aviation fuel, delivery van fuel, and bubble wrap and card board.
You could collect it and cast your own candles.
As I said, the customer still has to clean the parts to remove residue wax in most cases.
Even if the customers, just, as you suggest tip it down the drain, the above points would far out way this.
Then there are all the energy saving points I made earlier, combined with the increased density of the print run.
A big limiting factor in sprue design is the ability be able to cut the part free. This means the parts usually have to be spaced far enough apart to get a craft knife in, reducing density.
I am starting to repeat myself, but throw in:- Finished parts. No need to rework. Removing bits of sprue, and re-enforcement.
No handling damage. While cleaning or transport.
The customer has the motivation, leisure time, and space, to remove the delicate parts from the wax without having to meet deadlines, or the danger of a six inch model of the star ship enterprise suddenly landing on top of it. Or would it be a tardis.
Etc.Etc.

There is one last point, in that the customer would not have be in, or make special arrangements to receive the delivery.

Double checking again, with my last order. The printed hand rails.

As ordered and delivered.



The figures.

50 1/72 Hand Rails.

Material 1.15 cm3

Bounding box volume 12.6 cm3

I think this gives a packed density around 9.12



With the new method



55 1/72 Hand Rails. note 5 extra hand rails.

Material 1.51 cm3 Exchanging the sprue for a box has required an extra 0.28 cm3 after the extra hand rails are subtracted.

Bounding box volume 6.91 cm3

The packed density this time is 21.85

5.4 cm3 of wax. What price?


As you can see, not easy to pack tightly together as they are wires with larger ends. But I got 5 extra hand rails in an area half the volume, and avoided all the other problems. Again, I got no where near the minimum separation distance of 0.05mm.

After searching the net, and while I'm not sure exactly what print machines Shapeways use for FD and FUD, it seems that the support wax is a lot more expensive than I had anticipated, but still not prohibitive.
It seems to be in the order of half the price of the Acrylic polymer.
The one advantage that this manufacturing process gives us over other processes such as injection molding, is the ability to produce a finished part which requires no further rework, dimensionally.
The requirement to meet the minimum bounding box size, and sprue parts takes away our one advantage, and the added unnecessary production steps, with the resultant over sized protective packaging makes us even more uncompetitive due to the inflated transport charges.
I know this method would not suit, or even be desirable for all objects, but a quick scan through Shapeways shops shows the huge number of products that it would suit.
Add in the ability to have parts printed in the thinner sections, the leading and trailing edges of scale aircraft wings etc, without the risk of damage.
I have been looking mainly at the 1/600 scale, and am struggling now to compete with injection molding on wire thickness.
If my method was accepted, 1/700 would be possible, and the model makers who have been looking at 1200/2400 scales would be able to greatly improve their detail.
I certainly wouldn't expect to receive the wax for free, giving even more incentive to achieve the highest possible packing density.

In a nut shell.

All this is assuming that Shapeways reuse the wax. If it is only used once and disposed of, we are already paying for it.