Showing posts with label RepRap. Show all posts
Showing posts with label RepRap. Show all posts

Thursday, May 31, 2012

The Stereo Microscope is My Friend

If there is a tool that I count on more than my stereo microscopes, then I sure can't think of one.  I find a low power microscope will tell me things that I just cannot validate any other way.

And, the performance and precision of a 3D printer is no exception.  So, for the first time, I was able to examine the prints from the cube under 10x to 40x and analyze the characteristics of printed surfaces.

My favorite test shape is an extruded triangle.  It has straight lines, flat surfaces and sharp edges.  It's perfect for analysis.  Most of you know that I already had a RepRap printer before purchasing the Cube.  And, I put its output under the same microscope a while back.  That's how I found out that that one of the rods that controls the up and down motion of the print bed on my RapMan was slightly bent.

Here's what it looked like at various powers from 10x to probably 40x.  This is an edge of a triangle.  Notice the regular pattern of hills and valleys.

Here is probably about 10x...

RepRap - Triangle Edge at about 10x

This is probably at about 20x...

RepRap - Triangle Edge at about 20x

This is most likely around 40x...

RepRap - Triangle Edge at about 40x

Now, in reality, to the naked eye, it is not as ragged as it appears under the microscope.  Remember, the layers are .25mm and that is VERY small.  You can feel it rather than see it.  And, I know that some RepRaps might not show this particular issue.  But, it is so common that it has a name.  It's called Z-Axis wobble.

So, now let's put the Cube print under the scope.

First, the same kind of triangle edge with the grain going the same way...

Cube - Vertical Triangle, Edge at 10x

Look at that smoothness!  That's remarkably flat.  So, what about other grain orientations in an extruded triangle?  The is the edge of a triangle with the grain in a slightly different orientation.  The first triangle was vertical and this one was lying on its side.

Cube - Horizontal Triangle, Edge at 10x

But, the really cool view is at the apex of the edge looking down on the extrusion.

Cubify - Vertical Triangle, Apex of Edge - 10x

What about analyzing other features?  Like a hole without support...

Cube - Hole in Wall, No Support - 10x

The bottom of the hole is on the left in the above picture.  So, now let's look at the same hole.  But, this time printed with support.

Cube - Hole in Wall with Support - 10x

This is very thin support.  But, I haven't tried to remove it.  So, I don't know how clean the hole ends up after the support is removed.

But, all of you know by now that I love the behaviour of Pentagon shaped holes.  They NEVER seem to need support!  And, look how clean they are at every apex!

Cube - Pentagonal Hole, No Support - 10x

Cube - Pentagonal Hole, No Support - 10x

And, let's begin to wrap it up with some up close and personal shots of the smoothness of the edge of a sphere.

Cube - Circumference of a Sphere - 10x

Look how smoothly that sphere's arc is.  That's beautiful.

And we will end our wrap up with a look at the edge of a thin-walled vertical column.

Cube - Wall of extruded Column - 10x

I don't know about you.  But, I think these images clearly demonstrate the capabilities of Cube to deliver precision prints  This is EXTREMELY important if the things you design require tight tolerances.  I plan several microscope to camera interfaces and it is amazing how precisely the center of the camera's lens must be aligned with the center of the microscope's lens.  There is no margin for inaccuracy.  I'm convinced that the Cube will finally allow me to achieve this goal consistently due to the straightness of the walls it prints.

I hope this is helpful and not confusing.  I really do this for myself because it allows me to work WITH what I have.  And, as it turns out, I have a lot with the Cube.  :)

But, there is a reason why I share it with you.  I want YOU to know that my enthusiasm for this little printer is based on cold hard facts and not just emotions.  People can be enthusiastic on no basis at all.  Admittedly, the initial enthusiasm that gave rise to the name of this blog was a gut level response based on years of dreaming what my perfect consumer 3D printer should be.  But, then it was deepened by my driving from the DC area to Rock Hill, SC to see one for myself.  I didn't have my microscope.  But, I could see that the objected printed out right in front of me was remarkably smooth and precise.  But, now I have the objective tools to validate or negate my gut feelings and, as you can see, my instincts seem right on target.  

Let's compare the green Cube output with the white RepRap output one more time...

RepRap (White) vs. Cube (Green)

The scope doesn't lie.  A picture really is worth a thousand words.

Thursday, May 24, 2012

Tomorrow, Tomorrow, Tomorrow...

"Tomorrow" has played a significant role in so many dramatic productions, from Shakespeare to "Annie".  But, today it's playing a significant role in the drama that is unfolding as the first true consumer focused 3D printer is released.  Tomorrow is the day that the Cube 3D printer is finally leaving the warehouses and being shipped to consumers all over the world.

So, what will be receiving when the delivery truck shows up at our doors?

First, we will be receiving one of the most precise and well designed 3D printers in the under $2,000 category... the new Cube 3D Printer.  This printer has something that most RepRap printers do NOT have... a heated bed!  This heated bed, along with something else that will be in the box, "Magic Glue", allows us to use tough ABS plastic instead of the PLA I've been using.  ABS has qualities that PLA just cannot match.

Cube 3D Printer

Secondly, we'll be getting the Cube software that turns any STL file into a printable CUBE "p-code" file that the printer understands.  It not only does the conversion. It allows you to re-size and re-orient the print object.  But, for me, the best news is that I understand that it also allows YOU to choose to print or not print raft and support.   That is a HUGE deal for me.

Cube 3D Printer Software
Thirdly, we will be getting a Wireless Interface built into our Cube that allows us to communicate from our computer without a wired connection.

Cube Wireless Connection
Fourthly, we receive an EZ load Cartridge, containing the ABS plastic filament needed to print your 3D objects.  I've already got a backup of items that I want to print, so in addition to the cartridge that comes with the printer I ordered a 3-Pack of additional cartridges in 3 different colors.

Cube EZ Load Cartridge

Fifthly, we will be getting a USB flash drive holding at least 4 printable objects so that we can begin using our Cube immediately after activating it!  But, that is not all.  Additionally, we will be receiving either files or links to 21 more print files.  I assume that these will be made available to us via the Cubify web site.  

And, of course, all the necessary power cables will be there for us to plug our new Cube in, turn it on, activate it and start printing!

So, to paraphrase Annie's famous song... 
Tomorrow, Tomorrow.  
I love you Tomorrow.  
You're ONLY a day away!
OK... maybe FEW days away when we take into account the time it takes to reach us.  But, tomorrow, for many of us, it will mean our Cube will be on its way to us.  And, THAT is GREAT news.

Thursday, May 10, 2012

DC Stop - Cube Impressions

The Cube came to DC yesterday on the Cubify Odyssey Tour.   It was great seeing Adam again and meeting the tour team.  I will be posting some images later today and talk about the day.

But, right now I want to focus on the most important things for future Cube owners that I learned yesterday.


Anyone that has a RepRap 3D printer can really appreciate how scary it would be to mount 5 RepRaps in a Nissan Cube (NOT a Lincoln Town Car by any means!) and driving thousands of miles over every kind of terrain and running them in every kind of weather.  As much as I like my RapMan, it shakes nuts and bolts loose just sitting on a table!

Yet, the Cubes have made that trip and every one are still up and running like it was the first day of the adventure.

It reminds me of the days in the infancy of the automobile where manufacturers would compete in  marathon automobile races to prove the reliability of the newfangled horseless carriage!  I find the Cube's achievement in reliable performance to be very impressive.


Changing reels of filament in a RepRap isn't a terrible ordeal.  But, it is way more time consuming than it is with the Cube.  And, there is a big difference in the process.  With the Cube it is a two button operation.... Unload and Load. 


Because most RepRap printers are kit built, they include a process for leveling the bed.  Any, changes to the framework of the printer requires re-leveling.  The Cube's design does away with the need for the user to level the print bed.


In an earlier post I show a mechanics gauge that I use for precisely setting the gap between the print head and the print bed.  Again, I check this fairly often to maintain the best prints possible.  The Cube handles this for us automatically.  Take the Cube out of the box and start printing.


It is no secret that the only aspect of 3D printing that is less than enjoyable for me is removing raft and support materials.  The software for my current 3D printer will not allow me to turn off the raft even though I know that the item should not need one.  The software that comes with the Cube does give us that choice.  The tour team was printing a number of items having no raft and they held perfectly while printing and were easily removed on completion.  This is no small deal to me.


One of the things that was mentioned to me, as I explained to Adam, how much I was going to enjoy being able to turn off the raft, was that the Cube uses a new and better support strategy that is more common to the bigger machines than to the previous lines of extrusion printers.  The result is support that is easier to remove than what I've been used to.

This is very good news.  When I post the images I took, I'll point out a picture that demonstrates at least some of the differences I noticed right away.  But, I don't know that I have any really good images of support materials that had to be removed.  I know how to force a 3D printer to need supports.  So, one of the first things I'll do is check out the new support strategy.  But, if what I'm hearing is as good as it sounds, I am going to be one happy camper!!


While in general, I am not wild about having a single supplier for consumer products.  But, the reality is that at least at first Cube filament will probably only be available through 3D Systems.  That's categorically a bad thing, right?  Wrong!

I have tried filament from a fairly wide variety of vendors for my RapMan 3.2.  While I have found some suppliers whose products work well, I have yet to find one, outside of Bit From Bytes whose materials will immediately work well in my 3D printer.  I always have to create a new material profile and fiddle with the settings until I get the filament for behave well.  And, in at least two cases, I've had to abandon the material because it clogged my extruder's head to the point where I had to take the extruder apart and was fearful of having to completely replace it.

Yes, I am certain that we're going to have to pay more for the filament that we might if there was pressure from 3rd party vendors.  But, I've got to tell you that having the assurance of high quality materials with no need to fiddle with material profiles is a lot more important to me than the slightly higher premium in material costs.  Plus, we always have to factor in the waste of continually having to expend materials in testing new profiles.

To me, having one source at this point is a GOOD thing... not a BAD thing.  It gets us working immediately and keeps us working longer with less difficulty.


I already knew this from my visit to the 3D Systems headquarters a few months ago.  But, it is worth pointing out both the compact size and the light weight of the Cube.  Don't be fooled by the light weight.  It is still one tough machine.  But, being able to put the Cube in my car and taking it anywhere I'd like is an enormous advantage over my current printer.  And, it's an advantage that I plan to use a LOT.


I love the look, feel and toughness of items printed in ABS.  Unfortunately, I do not have a heated bed for my RapMan and without a heated bed I find it impossible to print ABS parts without the dreaded warping that ends up in aborted runs and distorted prints.  The primary reason that the Cube is able to use ABS plastic is that the Cube's print bed IS heated.  Plus, 3D Systems has come up with a proprietary coating that they call "Magic Glue" that is used on the print bed to further prevent warping.  I watched as an item that I KNEW would warp on my 3D printer, because of it's size, was successfully printed without lifting up at all.  I'm looking forward to finally being able to use ABS for my printed items!


My current RapMan printer is quiet enough that it is run in our home over night without disturbing anyone.  But, the Cube is even more quiet than the RapMan.  I hadn't known to focus on noise in my visit to see the Cube the first time.  But, this time it was one of the things I knew I wanted to check out since I now know I want to print at any hour of the day or night.


A quick visit on one day isn't enough for a definitive review.  But, I was very impressed by what I saw.  They will begin shipping May 25th.  So, I should have a machine in my hands before June.  And, I can assure you that it will be run virtually non-stop just as my RapMan has been.  In the meantime I believe that I have enough information to be convinced that the Cube can go head to head with any RepRap printer and come out on top in everything but build size.  And, believe me, build size is NOT the most critical aspect for 99% of us.  I have yet to use the full build size of my RapMan and out of hundreds of items printed, maybe one or two have exceeded the print envelope of the Cube.  To me the Cube is a clear contender for anyone considering a 3D printer and will be my suggestion to anyone that asks me for my opinion unless they have some highly unusual requirements that suggest otherwise.