Looking for more information (specifically equipment and materials) on SLS/SLA. . .

I'm trying to get Selective Laser Sintering and/or Stereolithography into my shop, but I don't even know where to start finding out about this stuff. . .

. . .does anyone know who makes/sells SLS/SLA equipment?

What about materials? Does anyone know if thermoplastic polyurethane elastomers are suitable for this process?

Thanks!

Hi atomicjoe:
Do you have any experience with the capabilities and limitations of each of these processes?
Probably the best way forward, if you are undecided, is to model up a test part, and have a company like Quickparts run it for you in the competing processes, then interrogate your samples to see how they perform for the criteria you care about.
Using a 3D printing bureau is also a good way to answer your question about what materials they can run with these processes; just ask them and they will definitely tell you.

3D Systems makes SLA machines and EOS (among others) makes SLS machines.
You should be able to get good information from them with a couple of phone calls.
Be prepared to spend a good chunk of money on these systems; they're in no way comparable in price to FDM machines like the Makerbot or even the Stratasys machines.
You're going to drop in excess of $100,000 for a stereolithography machine unless you can find a used one or buy one of the Formlabs machines.
There's one with a blown laser for 18 grand on Fleabay right now; it's an old machine that's been around for 14 years at least; it has floppies for the software and shows a maintenance report in one photo with an entry date of 2001.

I looked into the EOS direct metal laser sintering machines a few months ago...just north of 700 grand.
I'm told SLS machines are around a third of the price of DMLS machines, so figure in the $250,000.00 range for a top of the line model.
I really don't know what the used market is like in machines like these...as always, Google is your friend.
Cheers

Marcus
Implant Mechanix – Design & Innovation - home
Vancouver Wire EDM -- Wire EDM Machining

Thanks for the input Marcus. . .I have no idea what the limitations of the processes are and only know the capabilities of what I have seen in magazines (mostly high-end hot rod/muscle car stuff).

Our shop doesn't really have an application right now that would benefit from DMLS, but I definitely know we have an application for SLS assuming the surface finish, material, and precision necessary are there; off the top of my head I don't even know what the tolerances are for the parts I'm thinking of so I definitely have some more research to do, but I didn't even know where to start looking to find good information on this.

Thanks again for the info!

Joel

Hi again atomicjoe:
A thing to keep in the very forefront of your mind with purchases like this, is to determine how you intend to recoup your investment and then make money with a technology like this one.

Pretty much every 3D printing process outside of fused deposition modeling (FDM) is expensive to get into.
They will come down somewhat in price as do all things tech, but there are some pretty hard limits on how much you can cheapen technology involving motion control, lasers, and stringent material handling requirements, so I'm less hopeful for the kind of radical cheapening of machines that the FDM process enjoyed.

The other thing to note, is that companies like Quickparts have a really slick setup for getting you your stuff quickly, predictably and cheaply (although you may dispute that last contention a bit when you get a quote).

The point of all my blather, is to make the case that you need to keep a machine like this running almost continuously to make it profitable, and you're competing for business with companies that have a huge infrastructure advantage.
If you want to splash out for this kind of gear, and hope to do jobbing work on it (taking all comers instead of using it for your own in-house processes) you need to find a way to compete on that turf, and it's about so much more than just having the toy.

My own experience makes the point: I paid only 12K for a used Stratasys Uprint Plus (about half price).
I cannot consistently get work to put on the table because it's not my core business, so I won't put in the effort to make it as easy for my customers as Quickparts does: so to Quickparts they go for that service even though they're otherwise loyal customers of mine.
Now, I still get enough work (barely) to justify having the machine on my floor, but it's no moneymaker; it's a convenience for me and for customers who come to me for design work.

An engineer buddy of mine just bought a Makerbot for $1500.00, and it makes pretty nice prints, but he apparently has to fart about more than I do to get it going and to keep it going.
I can't afford that; I've got to keep busy doing what I do.
But he's competing on the same turf as I am, and you would be too, if you hope to do jobbing work on your machine.
His investment is a tenth of mine: my investment is a tenth of what yours would be.
He's your competition, as am I.

A last point; almost nobody cares what process was used unless they have very specific criteria for their parts.
Don't fall into the trap of thinking that your machine will be recognized and rewarded as better just because it cost more.

So think hard on what you actually want to do with your new machine, and invest accordingly.
I'd rather eat my shorts on a $1500.00 experiment than on a $250,000.00 experiment if this new wish of yours doesn't pan out.
If it can be made to fit your needs, go with FDM as a start and move up from there.

Cheers

Marcus
Implant Mechanix – Design & Innovation - home
Vancouver Wire EDM -- Wire EDM Machining

Thanks again for the input Marcus. . .our use would be strictly in-house. I thought it might be a cheaper (over the course of time) alternative to injection molding by getting rid of molds, mold repair/replacement, and reducing set-up time to make parts by going to direct digital manufacturing vs. setting up a mold in an injection molding machine and then molding parts. We do the same parts over and over, but they are usually small runs of parts at one time before we tear down and move to another part.

Hi atomicjoe:
I'm not sure you can make the economics work out compared to molding; the energy use to make a single printed part is high compared to molding, the material is expensive compared to molding resins, the maintenance of the equipment is expensive compared to molding and the time required per part is very high compared to molding.

However if you're talking about a continuously evolving set of parts that would require costly continuous fabrication of new tooling, you'd have a good candidate process with 3D printing provided you can get the physical properties you need from a printed part; unfortunately, TPE's are likely to be pretty challenging in that regard.

I don't think you can get the molecular crosslinking you need to get a truly elastic part from laser sintering, and you'd likely have to accept compromises in other physical properties like UV stability, tear strength, colour stability and on and on.

Have you considered working over your current processes to make them better?
For example, if you're finding a significant cost burden with mold repair, can you commission better quality molds?
Can you standardize your mold bases and clamp systems, cooling hookups etc etc to make them go faster?
Can you accept carrying bigger inventories of popular parts so you don't waste money on having everything JIT?

For the cost of bringing a 3D printing process on line and validating the process to your part requirements, you can do an awful lot to optimize what you already have.
If you're looking at a budget of a quarter million or so, you could justify a massive inventory of conventionally molded parts, and you'd know exactly what you have made.

I'd consider 3D printing only if the following criteria can be met:
1) modest physical property requirements; no big stretches, no high cycling rate, no harsh environment, no stringent cosmetic criteria etc etc.
2) relatively complex parts which would take expensive tooling to make
3) low total volumes (under a couple of hundred parts or so??) and fast part obsolescence
4) no aggressive production schedule

Geez, I sound like a real 3D printing hater; I'm really not, but this application doesn't sound like a great fit to me, even though I know very little about what you're trying to do.
So don't take what I'm saying as gold plated and incontrovertible; I may be way off base (but I don't think I am)
Cheers

Marcus
Implant Mechanix – Design & Innovation - home
www.vancouverwireedm.com

Another thought: I just browsed a web page for the new Arburg Freeformer that's coming out soon.
It's a glorified 3D printer but among its claims to fame is that it can run TPE's,and uses the same granulated feedstock that a conventional molding press uses.
It deposits droplets rather than a filament; the resolution is comparable to an FDM printer, and it is intended to be a production machine for low volumes.
It's worth a closer look I think, even though it suffers from many of the basic shortcomings of any other 3D printing process.
No definitive pricing information but apparently the gossips say somewhere in the 100K range.
MC

Thanks for the input again Marcus. . .sounds like you might be right; might not be a good fit for what we need, but that's why I had to ask. I had next to knowledge about the process(es) or capabilities before this.


Thanks again!!!

Hello Joe, Let me give you my case scenario. I wanted to have a part injection molded. I have a annual part useage of 400 pieces. The mold was going to be $10,000.00. I found some places that did aluminum molds at 3500 to 4000 dollars. Piece price for 400 was $2.25. The part was a 4oz shot of ABS.
I 3d printed the pieces with my 1500.00 printer. Used silicone rubber for the molds. I pour 2 pieces at a time with 2 molds.
The first parts I designed in cad come to find out needed fillets for strength. So I lost 2 molds about $80.00. Redesigned and printed the parts,they work great now. I get about 50 pieces out of 2 gallon kit of castng resin. Cost is 105.00. Generally cast while I'm internet cruising,every 30 minutes cycle new parts. As strong as injection molded part no. Haven't had to replace a broken part yet. But not having to re machine a mold is a huge money saver for me.
Just nice being able to print a part and have it in your hand to see just how big it really is.