Dont know where to post this (Rapid Prototyping)

[SrGilberto]

Hi all,

I've been tasked to pick up the manual and learn rapid prototype plastic modeling. We have a Stratasys FDM 3000 modeler. I work for a company that has had a lot of lay offs and (guess what?)... The only guy that knew how to use the machine got laid off. We are about to move our company and I have been afraid that they would sell or discard the machine since know one knows how to use it.
Well, I've told the boss I'd like to read up on it and learn it and so he's tasked me to go do it.

I've not found a rapid prototyping forum on the eng-tips site. Can anyone direct me to a forum regarding rapid prototyping/plastic modeling?

Thanks for any help,
Gil

 

[Demon3]

I worked a little with Stratasys a few years ago developing new rapid prototyping materials with them. It worked well.

The Stratasys system prints a thin wire of molten thermoplastic (polycarbonate and ABS are the common ones, polyphenylsulfone of the more expensive machine). It can also print a layer of a second polymer which can be dissolved away in water (this layer is printed in between moving parts to stop them from sticking together when you print the polymer).

You should not need to know much to use it. I haven't used it but I know that it's supposed to be just like printing to a printer only in 3D. You get in your 3D file and press "print", it does the rest. Maybe someone who knows more can explain in more detail. I'm sure Stratasys would be happy to help you. They make their money selling you the printer cartriges (spool of polymer strand) and they aren't making any if you can't use the machine.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[SrGilberto]

Thanks, Chris for the return.
I will contact Stratasys because right now, I'm having a bit of trouble. The last guy that ran the machine left the filament in the machine and it's been there for months. I'd like to restore the machine to the configuration as if we had just purchased the machine. I'm sure that means no filament loaded. So I have to remove the filament from the head and remove the spool of filament. According to the manual, when the machine is running, I press "Unload" then go to the rear of the machine and open up the "dry box" containing the spool. Then hit the "Unload" button a second time and then unwind the filament back onto the spool. This worked fine for the main filament. Now I'm trying to remove the support (secondary) filament, but that procedure is not causing the support filament to release from the head (or perhaps the tip).

If you can help with any ideas about how to get the support filament unloaded I'd appreciate. But I will also try to contact Stratasys.

Regards,
SrGilberto

 

[Demon3]

Hello,

The filament is melted around the tip so I can't imagine it will every release. It will be glued there. You cab break off the sold filament and rewind but there may always be some solid stuck in the tip. This is not based on experience but my understanding of how the technique works so you may need a pinch of salt.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[IRstuff]

I'm not sure why removing the filament is necessary. The deposition tip will simply melt the filament has necessary on the next job. Removing the filament means that you'll need to load the filament on the next job, which may require you to disassemble the tip and completely clean it of all residue.

TTFN

FAQ731-376

 

[Demon3]

Right.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[SrGilberto]

I'm currently cleaning the machine. I'm trying to learn as much about it as possible. It's okay if I remove the filament, because I need to learn how to install/re-install filament. It's all a learning process. I ended up breaking the filament from behind the head/liquifier, and then I was able to re-coil the filament on to the spool. Then I removed the head/liquifier and took it out of the cabinet. I was able to turn the motor gears in such a way that it backed up the filament that was still between the rollers. After removing the remnants of the filament, I've cleaned the whole head, removed the tips and have cleaned the machine. Now, I can just start from scratch and re-install the filament, and begin my next phase of learning, and begin to do the tutorial projects.

Regards to all,
SrG

 

[CelticEng]

SrGilberto
It sounds like you are getting somewhere.When the machines have been sitting idle you need to purge the head. The tips are best thrown away and replaced with new ones. If you remove the tips and load the filaments until they start to flow well.
With regard to the support material inspect it closely to ensure there is no moisture in it. You will see bubbles in it when it has moisture. It is possible that the roll of filament may be damp if it has been sitting in the machine for an extended perios and if so you are better off to throw it away and start with a new one. Never open the foil bags they are stored in until you are ready to use them.

When you find the material runs well remove any pieces that hang out of the head. Replace the tips. Use a heat resistant thread lubricant to ensure the tips can be removed easily next time.
Then load the new material until it flows evenly from the tips. (One at a time) Once again pay close attention to the support. As you have already found out it is very brittle and is prone to dampness.

You have to touch off the material tip each time you start off a job on the foam (make sure you start off with a good unused piece of foam or an unused area.) Hit modeler and bring the tip slowly down to the foam and embed a few thousands. You can use a shim of about 20/25 thousands between the support tip and the foam (with the modeler tip down) to check yourself. Eventually you will be able to do this visually.This ensures that you have set your Z-0 (zero) You have to hit (zero) I think. (it's been a few years since I ran the FDM 2000.)Then it should home itself in the center /rear of the machine.
Run a calibration box if you can figure that out and measure and inspect the wall (should be the same size as your tip, i.e .010" for a .010 tip)The wall should be centered/lined up evenly on the layer of support.
When you add your parts to the box /window in the software and send to modeler. It should be able to take care of itself after that. Just make sure nothing overlaps and that when you set zero in the machine (usually the front left corner) that you have enough room as indicated in the software window. The front left corner of the foam should be the bottom left corner of the software layout window.


If you need more help feel free to post your request. Where in the US are you located?

Good Luck