Visible Light / Near UV curable resins

Hey one question, how did you manage to get your LED source to collimate. As I heard from some optical engineers, in the DLP projectors the light souce has to have a certain shape (mostly a point source in lamp driven DLPs) to have a uniform exposure map at the projection surface. I do not know how this works in LED driven DLPs. Do you have some info in that regard?

The yahoo group is another hobbyist site like this one. I've seen a few projects start and then stall out.

[3dprinter.wikidot.com] is the test rig made from Erector Set parts? Reminds me of the 60's. [en.wikipedia.org]

[3dlprint.com] seems the farthest along.

[www.chemshapes.com] has stalled out again as well.

If you noticed I mentioned 385-390nm vs 200-365nm for the range of UV.

I fail to see the point of some of your comments, which seem rather dismissive.

Anyway, you are wrong. The furthest along is this guy:
[3dhomemade.blogspot.com]
He has ceased posting info on his build as he is planning to go closed source to sell kits. His reasons are his own.

You may scuff at what the yahoo group has published or, as so many others, not even bother to read some of the info that has been sourced there. But I wish you good luck with your project anyway.

Edited 1 time(s). Last edit at 12/28/2011 12:57PM by spota.

guys this will be a challege... i was browsing and found this amazin' 3d printer - they have used a cheap pico projector. check this [www.miicraft.com]

i can't wait to see your result guy... i buy resin from you guys..

more power.

This is interesting but a forseable result.
The pico machine has excellent resolution although a limited build area.
The cost of the printer is around 6000 - 7000$
Junior's printer kit is listed at around 4000$ and can easily replicate these results, an beats the Pico in build area size.
I still think that Junior and other DIY printers have the advantage here.

My 2 cents.

Okay I have kindly been pointed to the fact that the pico they are talking about is a *pico projector*, not the Asiga Pico 3D printer.

So ignore my previous comment, this is actually a new and interesting result they are showing!
Love the elastic polymer from the video...

Hello RepRap enthusiasts!

After years of dwelling among the 3D printing community and month sof arduous work sourcing providers and finetuning resin formulas, I am finaly done setting up a website that I will use as a platform to distribute my resins. You can have a look at:

[www.spotamaterials.com]

For now I have 2 resins available, a 3rd one coming shortly and a 4th still under development.

They are:
Spot-GP, a general purpose, low cost resin with good physiscal properties and excellent cure speed and low viscosity.
Spot-HT, same as above, but better physical properties all over the range: hardness, toughness, abrasion and chemical resistance
Spot-E: A flexible, rubbery and tough resin, soon to be available
Spot-IC is a resin aimed at investment casting uses, still under development.

All the resins above are made to be as safe as possible, with very low irritancy base products, with no volatile compounds (VOCs) and no Bispheno-A (BPA) or other known hazardous materials. I'm also trying to keep the costs low while selling packages of 1 and 5kg, and more on request.

Hope you'll like the results of my research!

Cheers,
Fernando (aka spota)

Edited 1 time(s). Last edit at 05/05/2012 02:50PM by spota.

Hi Fernando,

good to hear

I've delayed my UV-STL-development for two other, more urgent projects, but it's on the bench for May+June.

One of the following projects is about laser-applications for engraving and UV-curing, so fits perfectly

In June I'm job-changing to another company with a strong CAD-CAM background, so maybe some other related links too

---

Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Hey Viktor!

Seems like you have interesting times ahead af you.
I'm very happy for you and I know you'll have a good time!

Lookig forward to more input for your side.
I'll also have a go and post the news at the CNCEcke, as I have ventured to translate my web to German as well, I think people ther will appreciate

Cheers!!

I'm not familiar with the energy levels needed to trigger the curing process, but it might well be an alternative to use a laser LED on a cartesian bot (instead of a DLP). This would have the added advantage that not much would need to be reinvented (and it is way cheaper that a DLP).

Or am I missing something important?

Quote

Or am I missing something important?

A DLP can draw a layer in less than a tenth of a second. To reach a sufficient energy level you need to keep it steady for some time, but you're still in the range of few seconds.

A laser with mirrors can draw a layer within a second, because it's mirrors are extremely light and require minimal movement to draw a reasonable large area.

Now, do that with a cartesian bot, where you have to move at least half a kilogram over the entire surface.

That said, Mr. Hulls very first working stereolithography machine was a cartesian bot, too.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

... actually I'm moving the spot of a 200mW UV-diodelaser with my CNC-mill in XY, what's a really slow process, compared to a XY-scanner or a DLP-beamer ... but the accuracies are in the range of some microns, compared to some ten microns with the other systems.

But I have an XY-scanner system waiting until I'll have some spare time to bring it to work again ... and a 300mW UV-diode and a 400kW/100ps-pulsetime N2-TAE-laser, what's maybe interesting as UV-source for a DLP-mirror printer too.

Now I've begun my job at Delcam Germany, what's a CAD/CAM-software related company - so maybe some potential for synergy effects to/with Reprap? ... let's see

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Hi Viktor,

I presume your cnc mill uses threaded rods. Right? Belts can be much faster.

My point was that if you can show a frame with a layer's contour but you need to wait tens of seconds so enough energy is delivered to the resin, you can use a laser led in an aixiz housing (weighing about 20 grams) moved by a cartesian bot. Depending on the power relationship and the total area lit one or the other approach will be faster.

OTOH, it's been suggested above that high-power UV does not match well with DLP technology.

Definitely I'll stay tuned.

... maybe here interesting too ...

Found some UV-resin parts, that I've made some years ago - one of them in two versions: a complete solid body, or the same outer diameter with a hollow honeycomb-structure (images attached)

The dimensions of the cubic parts were 75x75x80mm, the solid was 348g, the hollow 130g.

The stability of the hollow part is excellent, it even withstands around 6years exposure in a mixture of mineral oil and fatty acid (ferrofluid) without remarkable changes ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

... and I guess the second point for hollow parts is that not only they are strong but they are also more cost-effective compared with a solid one. And the fact you can draw them more quickly if you use a moving laser beam does not hurt.

Just my two cents.

... the 'hollow' part was expensiver than the solid one, as the pricing was then made by total Z-height and after-finishing, not weight!

But for a DIY-approach the facts, that it will build faster and with less material, are true

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Profitable pricing scheme :-)

Hi all,
I have built a 3d printer, and am working on getting chemicals to make it work.
I have the recipe below but cannot find a supplier of Benzoilisobutylether (BIsoBE).
It seems to be obsolite.
!. can anyone recommend a supplier (im in Sydney Australia) or
2. An alternative recipe?
Thanks.

For 100g of final resin mix (RM)
3g of Benzil
1g of Benzoilisobutylether (BIsoBE)
1g of MDEA
Methyl diethanolamine is a clear, colorless or pale yellow liquid with an ammonia odour. It is miscible with water, alcohol and benzene.
Methyl diethanolamine is also known as N-Methyl diethanolamine and more commonly as MDEA.
0.5g of EDTA or 0.1g of Hydrochinone
complete to 100g with Polyester resin.
Cost of chemicals: 0.74

I would be very interested in purchasing some resin. I can't seem to find any on any website. What wavelength's are able to cure the resins you have available?

... take a look at spota's site: [spotamaterials.com]

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Hi

I find the resin for stereolithography. ( Viper si2 machine)
If you have the resin, please send us the quotation.

Thanks

hi spota,
i need a resin type for a 3d printer which works vis light range. dou you have some castable material available?
BR

Hello!

I just saw you PM with your request. I will answer you over there and we can discuss the details by mail.
As a general info, my resins work both in the visible blue as well as in the UV spectrum.

You can see details of the available resins here:
[www.spotamaterials.com]

Cheers!

Hi Fernando,

did you change the basic chemistry of your resins in general?

With your first samples I had excellent curing with 405nm but nearly no effect with 445nm @ much higher energies.

Haven't repeated this with the second 1kg-bottle, but will try this, when reassembling the 445nm-beamer ...

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Hello Viktor.

445nm is indeed in the extreme fringe of the activity of my prime photoinitiator. I do have an alternate one that works at 470nm and has a decent absorption at 445-450nm. But you have to take in account that this alternate photoinitiator is slower than th eprime one. But I have seen it being used in several resins used for DLP 3D printing, so it works.

I don't remember which photoinitiator I sent you, do you recall which it was?

Cheers!

... no further infos at hand - the three bottles were marked with #1 - #3. You posted me the specs in the emails and PM's, but it's no problem, as i'm using the resins in low quantities with 405nm, what's good working

... and have plans for 337nm and ultrashort pulses from the N2-TAE-laser

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

ah crap...

Back then I was testing several different resins and didn't name the samples very explicitly. But in the end I managed to evolve all the currently available products.

If they work well at 405nm it means you have the prime photoinitiator, which by the way should also work fine at 337nm. Actually you may need to be carefull with those zillion powered pulses or you'll cure the whole tank of resin in a pulse

... the pulses are specified with 400kW, but only 200ps long, so with 30Hz repetition rate it's something below 1mW averaged.

I have first to buy a bottle N2 and some armatures, so can take a while ... maybe faster, when finished the projects around 405nm ...

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I would be very interested in this also. As my username implies I tie flies. I have been searching for a visible light curing resin in both a thin and thick viscosity that will cure with a good led torch in the 365nm to 405nm spectrum. There are a variety of these out there already, Bug Bond, Clear Cure Goo, Tuffleye etc, but they are very pricey for a small amount. I would certainly be interested in these and may also be interested in purchasing in large quantities for resale as a newly branded kit if it works well. Would a light/torch similar to the following link be suitable to cure a resin of your design in fast period of time (5 seconds) or roughly how long would this take? Additionally, would thickness of rought 1 to 5 mm be easily cured with a like like the one below?

[www.lt-box.com]

Let me know what you think.

Eric

Hello Eric,

Theoretically this should work, but I have never tried to cure them with such torches. It is a matter of power, as the wavelengths you mention are very well suited. 3W in the window between 365 and 405 is actually plenty!
By thin and thick viscosity, do you know the figures or comparative liquids you are aiming for?

Also, I suppose water resistance is very important and a serious physical strength too. Is this going to be used in marine environments?

Cheers,
Fernando