Wanhao Duplicator 7 Discussion (Page 2 of 2)

The finished print is made of acrylic. I would not allow a kid to hsnfle it as it could end up in their mouth and it is not known yet if their is any danger in that. When I say brittle, think glass. A kid would destroy a print made with standard resin.

Hi, looking to get one myself. been 3d printing FDM for about 4 years now, do it as a hobby and for work..

does the duplicator 7 require anything purchasing besides the resin?
i have heard that with SLAs the resin vats have a very short life span and cost about £50 a pop... really puts me off.

currently stuck between the peopoly sla kit  &  wanhao duplicator 7.. any thoughts or advice?

Carl should be able to give you his insight on the Wanhao Duplicator, but I can give you some information that should help you decide which way to go.

The Wanhao D7 uses a 5.5" LCD panel with a resolution of 2560 x1440, and UV light source.  It's what is commonly referred to as a Direct LCD printer.  The resin vat/tank sits directly on top of the LCD panel, and The UV backlight shines through the transparent/white screen, exposing the resin in one single pass.

The Peopoly Moai is a true SLA printer, which uses a UV 405nm laser to "draw" the image of the layer onto the bottom of the vat, thereby exposing and polymerizing the resin. 

Additionally, the Moai uses a tilting peel mechanism, that adds a lot less stress to the model as it's being detached from the build layer, whereas the Wahao and other units like it, simply pull the part straight up.  This can have a negative impact on the model, and either distort/stretch it vertically, or worse contribute to the model or parts becoming detached from the supports, and ultimately partial or complete print failure.

Each technology has it's strengths and weaknesses, but in general, a SLA printer should be capable of producing finer details, but both SLA technologies are capable of surpassing anything that an FDM can do.

The Wanhao is more compact, already built, and with it's dedicated software easier to get started.  However the Moai offers a larger build volume, finer layer resolution and potentially finer surface details, but it requires assembly and learning at least 2 pieces of software to get started.

With regard to the resin vat/tank, yes they are consumables. 

The Moai tank uses a PDMS layer that acts as the drawing surface.  The resin cures on top of it, and is also attached to the previous layer.  So as the build platform goes up, it needs to detach the model with the newly cured layer from the PDMS.  The printer tilts the vat to gently detach the print from the PDMS, then the build platform goes up, and so on. 

It is the PDMS layer that over a period of time becomes foggy and doesn't allow the laser beam to properly shine through and cure the resin.  when this happens, you usually get prints that lack detail, or fail partially or altogether.  When this happens, the PDMS layer needs to be replaced.  In most cases, people simply dispose of the vat and buy a new one.  Other folks, the DIYers, will re-coat the existing vat with a new layer of PDMS, which is a lot cheaper in the long run (I'm one of those that re-coats his vats to save money). 

Peopoly claims their tank can last 4 liters of resin.  I think that in reality that number is more like 2-3 liters.  Different resins have different exposure rates, additionally, finer resolutions will expose the PDMS to extra exposures/passes, so your mileage will certainly vary.

The WD7 uses sheet of FEPat the bottom of the tank instead.  I don't have enough information to tell you how long that lasts, or what the behavior is, so I defer to Carl for that.  In the long run, it should be cheaper to run the the D7 compared to the Moai.

Prices of Resins have come down recently with the introduction of new vendors like Apply Lab Works, 3D Resyns and now Peopoly.  I think this is a good time to get itnot SLA printing if this is something you ever considered before but though it was too expensive.

Hope this answers some of your questions.

Wanhao D7 is NOT an SLA printer.
No lasers there. Its LCD projection.
Just to clear things out for those who posted it under this category

Define the difference between DLP and SLA ?
DLP using projection via projector or LCD
SLA using laser that draws the image similar to FDM printer
Two are not the same.

Sorry Carl, but you're only partially right. 

While a lot of Chinese 3d printer manufacturers keep referring to their progeny as SLA printers, the reality is the term was originally intended for laser based devices. 

SLA was originally coined by Chuck Hull, who went on to to found 3D Systems.  His patent specifically described "a concentrated beam of ultraviolet light focused onto the surface of a vat filled with a liquid photopolymer". Aided by CAD/CAM software, the laser would draw the outlines of the object to be printed onto the surface of the resin, thereby polymerizing the area.

At the time of it's inception (early 80's) the technology predated the development of the DLP chips by almost 10 years.  By the time Texas Instruments manufactured the first viable DLP chips in 1997, 3D Systems was already working on their 2nd generation SLA systems using solid state laser diodes.

Anyway, you're correct that, today, SLA is is used to primarily describe 3D printers that use some form of resin polymerization, but to correctly describe the differences between technologies, additional nomenclature must be applied.  Below is a link that describes in detail the 3 different processes, as well as their correct naming:

http://theorthocosmos.com/laser-sla-vs- … -compared/

Hope this sheds some light on the technology and its nomenclature.

Chipmunk ?

... Alvin ???  Is that you ?

I'm no expert but I think the bed should be touching the lcd with the fep in between. It sounds like you did it right or close enough. Try playing with your resin profiles a bit. I thought my d7 was broken until I basically doubled the cure time for my print. That got me something solid and attached to the bed. Then I started working my way back down. There is definietly a learning curve even if you have lots of FDM experience.

My 1.5 came with a bare aluminum finish on the plate.

mine D7 Plus is is the same.
Its flat for sure, but seems like it needs holes so it wont suck on the film when pulling it up.

Carl I have a question.
is the duplicator 7 a good enough printer to do lithophanes using white resin.
I know i would have to stand the lithophane on edge because of the bed size.
Looking to print  lithophanes 100 X 100

thanks
Dale

Dear all,

I want to open a Wanhao Duplicator 7 Plus, and replace its UV light source (~405nm) with another light source with wavelength around 500 nm.  Do you guys have any idea if it is possible or not?
If its not possible, then what do you think if I want to remove the whole LCD and add my own Texas Instrument DLP with its own software and light source and lenses? Do you have had any experience of working with this printer after removing its LCD? Is it possible to use it like an open source device? Thanks a lot for sharing your ideas, if any.