Another RP service provider

[Hauk]

Despite the higher prices from RJMRP and Redeye, they do have a much greater selection of materials, printing and finishing options, so though they may not really be applicable to our small part needs that we are discussing, they could well come in handy for larger items, or work related items........especially since it has now been shown that converting a Google SU file through CAdSpan to an .STL, will print with no problems from these companies.

I think companies like RJMRP and Redeye also offer a sneak peak into what we can expect from companies like Print-A-Part in the future.
The future of scale modelling have never been brighter!

-Havard

[Chuck Doan]

For now, I will I will do a little sanding. Of course it would be nicer to not have to, but it looks like the pricing gets higher.

PAP was the simplest one I came across, and so far the cheapest for this kind of material/printer.

THanks for the efforts and info! Hopefully it can only get better!

[finescalerr]

One point we seem to have neglected is the suitability of various resolutions for various scales. For example, Chuck is working in 1:24 and is able to clean up the "jaggies" on his parts enough that they disappear. But what if the same parts were 1:48? In that case I would think you would need a cleaner, hi-res part if for no other reason than to avoid problems with the part's basic shape. Maybe that is the value of the "high price-hi res" alternative sources.

The downside, of course, is that you may pay $100 for a few rather tiny items and, financially, the tail starts wagging the dog. But it is something worth considering.

Russ

[Chuck Doan]

That is a good point. I was also wondering how well this would work in the smaller scales. I was thinking about doing some larger scale stuff again.

[Hauk]

That is a good point. I was also wondering how well this would work in the smaller scales. I was thinking about doing some larger scale stuff again.

I have some friends that runs a small Model railroading business here in Norway. They are making a lot of H0 casting masters on Solidscape wax printers. They are quite pleased with the results.

By the way, I asked them about what metal they had their masters cast in, and they told me that the jeweller that makes the metal masters f prefer to cast them in silver! How classy is that!

-Havard.

PS: Metal Masters from Wax Masters? For those not familiar with the lost-wax casting process a brief description of the process might be in order.

1. Print or mill a wax master. This master can give you only one metal casting. Fine if you need only one part, but for larger runs it is uneconomical to print a wax master for every part.

2. Cover the waxmaster with plaster.

3. When the plaster has set, you burn out the wax with a torch or in a special oven. Adios expencive waxpart.

4. Fill the cavity in the plaster with molten brass (or silver as my snobbish friends does!)

5. Smash the plaster mould after the metal has cooled. Hello metal master.

6. Make a mould from the Metal master in RTV rubber or something similiar.

7. With the rubber mould you can make as many new wax masters as you need. For producing larger number of parts, the casters often assemble several wax masters into casting "threes". Then it is back to step 2. again, plaster moulds.

8. Repeat cycle as many times as neccesary. If the rubber mould wears out, make another one from the metal master.

There are a bit more to it than this, of course. The process  involves dealing with multiple steps of shrinkage, for instance. Please feel free to correct me if I have got things wrong, I have only had a few brass castings made this way, and the actual work took place in Korea.

[marc_reusser]

Russ,

Without having my actual parts to see, I think when using PAP in smaller scales (1/48 and down) your best uses would be for the base shapes/solids/parts of something. EI. tank car bodies, loco side or saddle tanks, tender shapes, diesel critter hood shapes, diesel truck cabs, maybe even things like sand/steam domes in 1/48. etc,......basically things that you would then finish detailing with styrene or PE parts. (FWIW) this is pretty much the approach I plan to use for the 1/35 stuff)

This is actually not so different from the way things already are whendealing with resin castings in the smaller scales, so many are poorly cast or poorly/incorrctly/out-of-scale detailed, that you have to shave off all of the details and strart over......so doing the base form in PAP is not very different, except that instead of removing and sanding, you are just sanding .


Marc

[Fred H.]

Well, we'll see! I'm going to make a few small C&S steel underframe parts using the CNC milled alternative thru RJMRP. I'll keep ya'll posted.

Examples:
- Centerbeam to crossbeam (two I-Beams) casting.
- Draft gear pocket.
- Coupler lift brackets.
- Brake wheel top/bottom brackets.
- Sidesill cast supports.
- Bolsters!

Don't cuss me out if I've got the names wrong! (But feel free to correct me!) See original C&S blueprints.

Fred H.

[SandiaPaul]

Fred,

where did you get the C&S drawings?

Paul

[Travis]

Hello everyone!

My name is Travis Serio and I am one of the lead project managers for RJM Rapid Prototyping. Fred contacted me and told me I should get involved in this wonderful community. Hopefully I can answer some of the questions many of you have regarding various forms and styles of high resolution rapid prototyping.

I see that many of you are utilizing print based technology from an Invision HR and of course for some scales this resolution is more than adequate and for other scales it is not adequate enough. This is where we come in. We push to go to that next level of resolution and detail in the RP world. As many of you know we are focused heavily on Jewelry manufacturing and prototyping. The jewelry industry is perhaps one of the most demanding industries in terms of resolution and accuracy on a small scale. The surfaces have to be mirror finished and intricate stone settings require features that can be plus or minus .001".

I have attached an image of three spheres which should help illustrate the resolution differences between what most of you are probably familiar with and what we produce. All three spheres are 15mm in diameter. The Purple sphere was produced by us at RJM on a modified Viper SLA system. The Blue sphere was produced on an Invision HR at its highest resolution and the Clear/White sphere was produced by an Eden 333 on its highest resolution (Red Eye).

[lab-dad]

Welcome Travis!
Will be excellent to have "an inside source" in our ranks.
I am sure we will all benefit from your presence.
Just for giggles how about a price comparison of the three spheres/materials?
-Marty

[Chuck Doan]

Welcome, thanks for stopping by! My only experience has been with the Invision machine. I would also be interested in the general cost differences in the process for similar parts.  So far I have been using the parts directly as opposed to using them as masters for castings, so I would have to weigh the cost differences.  I think for master use, a higher price can be tolerated.

[marc_reusser]

Travis,

Welcome, and thank you for your time, information and examples. Very much appreciated.

The differneces are quite clear. I too would be interested in the same questions posed by Chuck.

When I went to your site it was quite obvious that your services and results were geared to a higher quality market than the hobbyist that needs a few parts here and there  . ...as well as somone that is more well versed than many a hobbyist will be when dealing with .STL files. (neither item being a negative).....what confused me, was that your .STL verifier seemed to pick out some errors (lapped components) and noted the pricing would likely be higher.....while the PAP and Red-Eye verifier did not seem to flag this. Would you mind if I asked some questions re. this in regards to the project I tested, so I can better understand how to adapt my files for use with your services?

Re. pricing; though your base price was higher, which is well justified by the obvious quality difference, I would have been OK paying it, but as Chuck mentioned, for parts that were to be directly used,...and though I understand the reasong and need for this......I felt deterred by the additional min. charge cost.

Thanks again. Look forward to any additional light you can shed on the printing subject/process.


Marc

[Travis]

Thanks for the warm welcome. I've tried to drum up some more photos of things we have done that might be along the lines of what you guys are doing here, or just simply show the scales we are typically working with.

I can sort of answer Chucks question on pricing (I hope).

I guess I should start by addressing the fundamental differences between our SLA and Printer based Jet technologies.

SLA uses a laser to build parts from a photo resin. The printer based technologies you guys seem familiar with also use a photo resin but layers printed instead of cured in a vat. Traditionally printed parts have a lower XY resolution due to the fact that the material is being deposited by a Jet or print head and the resolution becomes fixed based on the size of that droplet (how small of a square can you print before its just a circle).

SLA is traditionally higher resolution because it uses the diameter of the laser beam to harden the part as the beam passes over the surface level of the resin tracing the outside features of the part. In our case, we have taken the existing SLA technology and modified it slightly to use smaller layers and have a slightly smaller spot diameter. The result is much higher resolution with the trade off of part size. It takes us about 3 times longer to build parts than a standard SLA machine and thus is more costly to keep the machines running.

As for the pricing per part it definitely varies from geometry type to geometry type. Parts with more area and volume and more complex surface areas tend to have the highest prices as they require the longest draw times and consume lots of laser time. You can expect most of our parts to range between $30 - $300 depending on their size and features. I would imagine that by the time you got to a $300 part you'd most likely be large enough to utilize the printer based technologies that can provide a suitable resolution for the job.

Some of our other machines also utilize photo resin technologies but instead of lasers they use DLP chips much like those in DLP televisions to project a mask onto the surface of the photo resin. These machines can achieve some very stunning XY resolutions that are unmatched by any other technology in the RP world today, but have a harder time building bigger parts that have big planar surface areas where peeling of layers becomes problematic (we can delve into that later).

For now I have dug around on my PC and attached a few more photos I've dug up to illustrate some more of our work. We've been doing a lot miniature soldiers for a company that makes miniature battlefield replicas for museum's and collectors (1st Virtual Productions).  Lately we've been doing a lot at 1:300 scale but have built them as small as 1:500 scale. The average height of a 1:300 character is 7mm from base of the feet to the tip of their bayonets on their rifles. Many are done in separate pieces, cast in silver or brass and then hand painted and assembled.

[Travis]

more photos

[JohnP]

Hi Travis,

The examples look good for a master for multiple castings where the cost is spread out per piece. Very nice detail on the garden building.

Would it be more efficient to divide a larger part into smaller sections and later bond them? Would that avoid the higher costs of a more voluminous part?

I admit to ordering a couple parts from PAP. I'll have to get an estimate from your company next time too.

Thanks for stopping in,

John

PS Marc, perhaps you had small overlaps that the other systems could not duplicate so their programs didn't care?