Friday, May 31, 2013

USB memory stick and System power

Since the memory stick has to be constantly plugged in and out of the CubeX, it might not be a bad idea to plug a USB extender cable into the CubeX and then plug the memory stick into the extender cable. The extender cable is easily and cheaply replaced if it gets damaged from the frequent plugging in and out. -   Just a thought.

Since the CubeX does not have a real power switch, it is advisable to plug the CubeX into a powerstrip with an on/off switch. That way if something goes wrong you can quickly turn it off, also easier for power off, than unplugging.

Wednesday, May 29, 2013

For new CubeX users. - Getting started with your first Print.

(This is based on what I learned during my little frustrating initial start)
If you are just getting started with your new CubeX here is what I can suggest:

  • To avoid possible frustration or disappointment, don't rush into your first print. It is not just "plug and play", but it is not that difficult either once you know and understand the basics.
  • Take the time and read thru the User guide to get familiar: CubeX user guide 
  • Read thru the different posts of this blog, hopefully you find some useful information. For example Posts: "Successful 3D Printing - Part 1", "Initial Setup", and other Posts.
  • Start printing a small part first. You won't use much filament and get a quick result.             Here is a good starter model from Thingiverse: "Treefrog by MorenaP" It is a cute little frog that prints in 10 minutes (when scaled down to 50%). Make sure to use these print settings: PLA material, 0.25 layer thickness, Medium density, No raft, No support, No fine detail preservation. Scale part to 50 percent. Also rotate to frog model 90 deg. so its looking to the side when you set it up in the CubeX software. In this oritentation it will print nicer since the overhang under the chin of the frog is not facing to the front where the print start / knit line is. (see other post about "Part orientation.......").
  • File link: "Treefrog by MorenaP"     Or print some of the model files that came with the printer. You can scale them initially a little bit smaller for a quicker print time.
  • Print in 0.25 layer to begin with. I print almost everything is this layer setting. It prints fast and gives a nice finish. If you want to try out the 0.1 or 0.5 layer height, print smaller parts (like the frog sample above) so you get a quick idea about the difference and can compare.
  • Print with PLA first.  - ABS is a lot more challenging to print with. ABS has a lot higher shrinkage rate and parts tend to warp. It is challenging to get good adhesion to the print bed and perfect print bed leveling and z-gap is needed. So get good with PLA printing before trying out in ABS.
  • If you have a CubeX Duo or Trio, and want to print a multicolor part, make sure you have successfully printed in single color first. Check the User Guide, and see the post "Multicolor parts with CubeX" in this Blog for some info on multicolor printing and a suggested  test print file.
  • Have fun printing.

Tuesday, May 28, 2013

Z-gap. What is the proper z-gap?

The z-gap setting is quite important for optimum part adhesion to the printbed and clean part finish at the bottom surface.
It is a good idea to watch from the side and the top when the CubeX prints the first layer. Looking at the first layer print lines you can quickly see if your z-gap setting is ok.
The first layer should be a little smushed onto the print bed so you get good adhesion and no gaps between print lines.  A z-gap of just under 0.1mm should do that. Some use just a sheet of paper to check the z-gap.
If you print with ABS, you want your z-gap a little tighter, close to 0.05mm.
See the illustrations below:  (another CubeX user found them somewhere on the Cubify website, - thanks J. Andre!)

In general, this is what I do before printing:
  1. Select the "Home" button. This will move the print jet behind the print bed so you can do step three.
  2. Make sure the jets don't have any (not even a tiny piece at the tip) of filament left stuck on them otherwise it can affect your z-gap measurement.
  3. Hit the "z-gap" menu button and check or adjust the z-gap with the up/down button.
  4. Then print. 
Note: Always "Home" before setting or checking the z-gap. This has been most consistent.

See also Cubify website for z-gap setting suggestion.


Monday, May 27, 2013

Software version 1.03 available

A new software version for the CubeX is available for download.
Some bug fixes and improved zooming / move feature and auto placement.

Click the Download software for Windows button in the middle of the screen.

Friday, May 24, 2013

Dimensional accuracy - Part 1 - Small parts and features

All part were printed with PLA  (I will repeat the same once I get my ABS)
All Dimensions are in mm.  (0.1 mm = 0.004 inch) (1mm =0.04 inch)
Parts were measured as they come of the printer.
No cleanup done on the parts.
If there was a little bump on the corner or so, I ignored that for the measurements

See summary at the bottom.

Picture of printed test parts:

Some of the walls did not close on top. I have seen that on some other parts too.

Download excel file:  Excel file with measurements
Holes printed with part laying flat, gives best holes size results.
Holes printed with part on its side. Holes turn out slightly oval

Summary for PLA prints:
Overall the dimensions are very close to the designed dimension and are repeatable. - Quite nice for a plastic printed part.
  • The minimum wall thickness it prints seems to be 1mm. (I think that is a double pass. Would be nice if it would let you do single pass for even thinner features).
  • 1mm small hole did not print in the vertical direction, but somewhat on the part in the horizontal position.
  • 1mm small cylinder did not print. Seems to be too small.
  • Holes print a tad smaller. (Better smaller than larger so you can drill out to exact dimension for critial fit).
  • Horizontal holes print slighly oval.
These are all small dimension parts, I will follow up with a larger part dimension accuracy post.

Monday, May 20, 2013

Natural PLA Vase print

I like the look of the natural PLA.
Just finished printing this beautiful vase.
It printed super nice, no model clean up needed.
I just added a large round "helper pad" at the bottom for good print pad adhesion and stability. (it was needed since the bottom of the original model had only a few contact points to the platform)
Print settings: 0.25 Resolution, Hollow fill, No support, no raft. Fine detail not checked.
18h 19min, 128 gram

Here is the model file:
vase zipped file download

Sunday, May 19, 2013

Multi color parts with CubeX

Another CubeX user had questions regarding Multi color printing.
One of the questions was why do the colors assigned in Cubify Invent do not translate into the .stl file?
I have not done much multi color printing since I had not much need for it yet, but this is what I have learned so far: (please correct me if I am wrong).

Feature colors assigned in Invent or any other software can not translate into the .stl file. It could be a possible future feature, that in the CubeX software where you create the build file, you could assign colors to features of the part, but that might be difficult to do for the software depending how the .stl file was created.

Anyway, right now for multicolor parts, each color needs to be its own .stl file.
So if you create something in Invent, you export it into a .stl file which you then open with the CubeX software to create your build file which you put then onto the memory stick so you can print it with the CubeX.
In the CubeX software, you use the "Open Model Assembly" button to bring in each different .stl file. At this point there is no color assigned to the model yet. The software places the different .stl files in the same coordinate place. (on top of each other) Then you can assign what printjet/color for each .stl model to use.
For example this two color earth model. It consists of two .stl model files. One is for the "water". The other for the "land".
"Water".stl model

"Land" .stl model

Combined with colors assigned

Printed part.

If you are just starting out with multi color, print something simple first. Multi color parts take long to print because it has to swap between print jets. It takes especially long if you have multiple colors per layer, versus the traffic cone below were the colors are on top of each other and not within the same print layers.

This is a good sample part to start out with for multi color printing. Print in 0.25 resolution. You can scale it smaller for your first test print. You have to load the different "ring" files into the CubeX software, then you can assign the colors to the different rings.
If the "rings" on your printed part are not perfectly concentric, if they are just a little bit off, that's ok, I would not tinker with the offset calibration since there is some tolerance to it, if they are far off, then your printjet offset calibration needs to be adjusted.
Here are the files:
traffic cone ring 1
traffic cone ring 2
traffic cone ring 3
traffic cone ring 4
traffic cone ring 5


Thursday, May 16, 2013

Successful 3D Printing - Part II - "Why did the print fail?"

See also earlier post: "Successful 3D Printing - Part I".

 If you are just starting out, I would first print one of the supplied models:
For example: XXXXXXX      (will upload examples soon).

"Checking the model if it is printable"
This should have been in "Successful 3D Printing - Part I".

After I printed a few of the models that came with the printer, I went online to download a bunch of other models, for example from Thingiverse or other sites.
But not everything is suited or designed well for FDM 3D printing and modification and support structures are needed.
Thankfully some users post pictures of their print of a certain model so you can see how it might come out, but often you only see the 3D CAD model.
The CubeX software has a very nice feature that lets you see and scroll thru the Build file to see the layer build / slicing.
If you have model files where you have not seen successful 3D prints, looking / scrolling thru the build file can give you a very good idea if your print should come out fine or might have some issues.

I wanted to print a nice spider model and found one on
I downloaded it, build it in the software and started the print.  -  not so quick  !!  I watched the printing process for a few minutes and saw some problems.  - Abort !  Abort !!

Here is what I should have done before printing:

This is the model before building the print file:
Always keep in mind the printer prints layer by layer.
When looking at the model it is obvious that the part needs support structure since the spider body is in mid air. But you could think that the legs might be able to print without support, since the printer can gap small horizontal distances. So lets create the build file.

After you build the print file, first save the printfile (see File Management for file naming suggestion), then close the Model file. (You could also close the software and just open the Build file which does not contain the original model anymore). 
Now the Model file does not cover up the Print file and you see only the build file and, can toggle the print jets for Part, Support or Raft on / off.
When scrolling thru the build file with just the spider (jet 1) turned on, the problems become obviously. You can see that some of the spider legs are not touching the platform, the legs that are touching are so pointy an provide no support for an angled upward build. The thin sections in the legs tiny thin.
So in this case selecting "Raft" when building the part would not help for the legs were they start on the build platform. I opened the file in Cubify Invent and created a plane (blue plane, see below) at a level that intersects with all legs. Then I cut everything below that plane. That ensures all legs are touching the print platform and removes the pointy ends of the legs. Some models might not have a flat bottom surface, so you can either cut one like in this example or the part would need some other support structure.

Even now with the better bottom contact points for the legs, one should either use "helper disks" Helper disks zip file (see in earlier post about part lifting) and slide those under the spiderlegs to provide a larger contact and support area since the build of the legs is in an angle upwards and that little contact area of the legs only would not hold that angled leg once it is building up higher.
 Or you could design some pads in Cubify Invent underneath the legs.
These are just some examples how some of the issues could be addressed and solved.  In case of the thin sections in the legs, I don't have an easy solution to fix that, exept cutting the legs off and creating new ones with not as small sections.
 Where the legs bend around is another problem area. With the thin sections in those legs and the designed shape really cause problems. The printer can print over horizontal gaps, but only a small distance. In this case additional support where the legs curve around would be needed.
With the selected "support material" option, the body of the spider should print fine.
This all is just an example what to look for in a more challenging part for 3D printing.
In case of this spider model which looked great as just a 3D model but is not 3D printable without some rework and redesign. I would first look if I can find a better suited model for 3D printing or design my own spider model. 
So for most prints unless they are very simple and straight up, I scroll thru the build file and check for possible issues to avoid bad prints and disapointment hours later. 

Wednesday, May 15, 2013

Any Suggestions for this Blog?

Feel free to post comments or suggestions for this Blog.
Trying to make this Blog useful by sharing my experience with 3D printing and the CubeX as I am learning.
It's becomming more and more fun with gained experience. Have had a few mis-prints early on, but understand now better why and keep learning.


Monday, May 13, 2013

Part orientation and part scaling

Here is an example how the positioning of your model on the print bed can somewhat affect the print quality of your part.
Each print layer has to start somewhere, and it is usually at the front, and sometimes the print layer starting point can be visible.

The Owl that was printed in "Thick" fill was oriented facing towards the front (toward touchscreen) on the print bed.
In this case how the owl was positioned, one side of the overhang of the owl's beginning of the head, was right at the layer print start and it caused a "droop" of the filament.
See picture below.
I printed the Owl again but had it rotated 180 degrees on the print platform (z-position), so the owl faced the other way. Now with the layer print start at the back of the owl the over hang at the head of the owl did not droop.
See second picture below.

It's good to study your part a little and where critical features like overhangs or cosmetic features are and position it accordingly on the platform to get the best print. Often the "knit" line is not even visible, but I am making it a habit to be aware at least when setting up the model for the print build.

Holes in Parts
Holes in a part tend to be a little smaller when printed than the size in the model. The printed hole being a little smaller is kind of good because if the hole is critcal, you can just drill it out to the exact dimension. (Look for a post coming up soon with measurements of model vs print sizes).
Drilling and tapping in PLA should be done at very low speed so you don't melt the plastic.
If you have an option, position the part so the holes print vertically. If holes are printed horizontally, they can tend to print a little oval, especially bigger holes.

Part scaling.
Here are some examples what can happen if parts are scaled down too much. So features or gaps get too small and the part or portions of it might not come out so well.
I printed the Eiffel Tower in smaller scale than need to be for 3D printing and the details at the top of the tower became too small to print successfully. Overall the tower still came out quite nice, but I will print it larger the next time.
So it is always good to review your part when you build it in the CubeX software and look at the feature sizes also look thru the slicing after the build process if there are gaps or overly thin areas.
Many 3D models online are not specifically designed for 3D printing and might need support features or modifications, so it's always good to check if somebody else has successfully printed the part.

The Cuban Chain, is another example where I scaled the model down too much. I saw it already when looking thru the slicing in the CubeX software that the small scaled down version would have issues, but I printed it anyway for example purpose.

And here are just some more other fun prints:
The translucent Natural PLA is pretty cool. You can print multicolor with internal features or parts that will show thru.

Friday, May 10, 2013

CubeX 3D Printer Review and Test

 (Review updates are at the bottom of this post)

May, 2013     
So I had the CubeX trio for almost one month now. I created a blog to share my experiences which might help others, but also hoping to get feedback from other CubeX users.

My background is mechanical engineering, working on instrumentation and systems design in the medical field and using SolidWorks 3D modeling software a lot.

The waiting time for the CubeX shipment was quite long because it was a new product release, so I almost ordered a Makerbot Replicator X2, but the waiting time there was just as long.

Quite exciting when it finally arrived, so I got one of the first batches.

The setup sheet that came with the CubeX is too brief and does not tell all the important stuff to get started and print successfully, so reading thru the user guide is suggested. (There is an updated version on the Cubify website). And check out the “Initial Setup” post in this blog.
One of the internal packing straps seem to have come loose and the print bed got some shipping damage and flaw. Luckily there was enough useable print area to continue till I got a replacement part. The customer service was very quick sending the replacement part.  -thanks. The packaging seemed otherwise adequate, the strap must have just snapped. The shock sensors on the shipping box were all tripped, but I guess any shipping will do that usually.

Of course at first I just rushed immediately into printing something but got a bunch of spaghetti because I did not check the initial basic but important setup steps. (z-gap, wiper offset, etc.)

The system startup is very quick and the touch screen menu is pretty straight forward. First I did not like the touch screen so much because it required some force to activate properly, but after some usage it seems to be ok now.

The print bed leveling take a little practice, and the front leveling screw is covered by the large print bed, -but there is a easy workaround (see "Print bed leveling aid" post). Without this little modification, the printbed leveling is a pain.

The printer comes with a bunch of sample print files, some are pretty nice and some very basic. My first print was the Dino head which I scaled way down to not waste filament if something was setup wrong. But the print came out great.

The "Cubify Invent" modeling software that comes with the CubeX is quite nice. It imports STEP, IGES, SAT, and SolidWorks files directly and can fix or heal models. So I import a SolidWorks file directly and have Cubify Invent convert it into a STL. file. There are also several other free solid and surface modelers online to create, fix or convert models. I do wish the Cubify Invent software could import .stl files. Hopefully in a future version.

The CubeX software then takes STL. files and creates a build file with the chosen parameters.

In the CubeX software you can select the print parameters, (3 layer height/resolution options, Four fill options, etcc) also what color/print jet to use and scale the model. But overall very limited in print parameters compared to other slicer software.

So far all my prints have been with PLA, since the ABS was on back order, but should have it soon.

I have not found any reviews for the CubeX but have read thru many other reviews or blogs of other 3D printers, so I don't have a direct comparison.

Here are my overall general comments:

The CubeX is fairly large and heavy, but as compact as can be for the capable print volume size and the mass is probably needed to be stable.

The xy stage is very solid with large bearing surfaces.

The z-stage is absolutely wobble free with its flex mount for the drive spindle.

Overall solid, clean design and cable routing (except a cable underneath the unit that can get in the way of the power cord but can easily be tied away).
Very easy access to everything and to the print bed due to the large front and side openings and removable lid. Can always see what's going on when printing.
The print cartridges are nice and keep the filament protected, but they are a bit expensive. Many colors are available.

The filament is fairly easy to load.

Having the CubeX trio, I could print 3 colored part, but so far have only done one three color test print and two 2 colored parts. With the current software setup printing a part with multiple colors can take very long, especially if there are multiple colors in one layer. For example the two color Globe model where one color is water the other earth, compared to the traffic cone model where the different color rings are staggered on top of each other which prints a lot faster since only one print jet is heated and printing at a time, so when switching colors, there is a pause till the other color print jet is heated and ready to continue. This uses less energy, but takes a lot longer.
The $ difference between the CubeX Duo and Trio is quite high ($1000.-)
To me, I don't think I really need 3 color printing much and my multicolor print results have been not what I expected, but with the Trio, it is very nice to have always 3 colors or different materials immediately available for printing. Printing supports / rafts and parts with different materials or different colors takes a lot longer.
Choosing between the CubeX, CubeX Duo and CubeX Trio, I would go with the Duo and get the aftermarket heated print bed.
So far the printer has been reliable and robust. It prints very consistent. If a print comes out nice it will again the next time, if some challenging part prints with some flaws, they will be the same on a repeat print.
The supplied "glue stick" works quite well (once you figured out how to properly apply - see the blog post). I have not had any parts "lift off". Very happy with the glue, and it dissolves with water so it's easy to clean the print bed. Just put the print bed into the sink and rinse with cold water, the part will come off with a few pushes with the supplied spatula, then scrape the print bed with the spatula and running water and dry off with towel. - ready to go for the next print.
I really like how quickly you can go from power up to printing.

I power it up, (the print bed was already cleaned after the last print), There is no real on/off        switch so I have it plugged into a power strip to completely turn it off when not in use.
Hit the "Home" button.
-  Make sure the jets don't have any filament left stuck on them otherwise it can affect your z-gap measurement.
-  Only for larger parts I recheck the print bed leveling to ensure good adhesion over the whole part
Then hit the "z-gap" menu button and check or adjust the z-gap with the up/down button.
-  Properly apply the "glue" to the print bed area the print will be on.
Insert the memory stick with the print file and load the print file.
Make sure the glue is tacky.
Start the print.
-  The print jet will heat up and then it starts printing.

I usually watch the first layer to go down on the print bed properly, but which has rarely been a problem since having this setup routine.

The initial software had several bugs, none which prevented printing, but a little annoying. A new software update to fix the know bugs was shortly released, also with some added features like "draft" print and "hollow" print. The user menu and workflow was also improved. (yes, keep on improving).
The software interface is intuitive and easy to use. I like the ability to ability to scroll thru the slicing and see the print pattern. This is quite helpful to avoid misprints due to too small of features or to see if support for the part (overhangs) is needed. I have scaled models down in size for printing, but then realized looking thru the slicing that some features would have not printed because the scaling made them too small.

The build process in the software is quite fast, and it tells you the approximate build time. The given build time seems to be an approximation, since prints have taken shorter or longer than the estimated time. Longer prints have taken usually hours more than estimated.  It is still also good to use to compare the print time differences between different resolution settings.

There is a "fine detail" enable checkbox, which pulls the jet away from the part so the fans can cool the part before continuing, it can give better detail results, but will take longer to print. I have not played much with that feature yet. When I used it, I got more "fuss" on the part. Don't really care for that feature, also I could help on some models from the plastic getting smushy (too hot in small detailed areas).
Most of my prints so far have been in 0.25 resolution with various fill settings. The CubeX seems to be well tuned for this resolution, it prints quite nice and reasonably fast. (See 2 posts with pictures and settings of printed parts in this blog). Have done two prints with the 0.5 resolution, but the layer stepping was very noticeable and overhangs did tend to droop. I think 0.35 could be a better alternate resolution option. Since the 0.25 prints come out quite nice I have not experimented much with 0.1, partially because the print time is of course longer. The 0.1 did excellent and very detailed on the "hand" print.

The file transfer is with memory stick, but I wish it was wireless. I bought an aftermarket wireless memory stick, but have not gotten it to work yet, so I am swapping the memory stick between PC and CubeX, not too big a deal but still hope to get the wireless stick to work.

The printer has a jet wiper to clean the jet off before printing.
The possible print volume is quite large. Not sure if I need it that big, but it also gives me the option to print multiple parts on the platform in one process.

My print bed is not perfectly flat. It droops in the corners. So far my prints have not been large enough for that being an issue, but I would expect the print bed to be flatter.

Not plug and play, but fairly easy to use and low maintenance so far.

It is quieter than I thought it would be when printing. But for overnight prints I'll keep the door shut.

Customer support has been great and very responsive, even got email responses after hours or weekends.

Compared to what I have read on the other 3D FDM (fused deposition modeling) printers, I am happy with how consistent and solid the CubeX has performed printing with PLA.

Getting more familiar now with 3D printing and understanding the process and process challenges, I am hoping that there will be soon an "advanced user" menu available for the CubeX where advanced users can fine tune print temperature, more layer height options and selective support structure options.

The basic print options can produce quite nice prints (see in my blog) but more complex models might need some fine tuning and support features. That would be the case for any FDM 3D printer.

I printed some prototype mounts I needed for work and it is nice to have a part overnight. Even using PLA the mounts are working great. Mounting holes and counter bores are coming out great. Hole sizes print a tad smaller, which then can be drilled to exact dimension. Taping a tread into PLA was not an issue and the thread is quite strong. Just have to drill and tap slowly to keep the heat down and not melt the plastic.

I keep a log of all my prints in a excel sheet with part name, print time, part weight, color, etc.. So I can easily see the part cost and how much filament I have used.  The CubeX tracks and displays how much filament is left in the cartridge, but I want to compare and have my own tracking.

3D printing at home for the consumer is still very new and is definitely not plug and play (yet).
One needs to understand the print technology and printer setup well, to get successful prints.
There are many things/models that will print just fine, but one needs to understand the FDM 3D printing process and limitations. Not every shape is successfully printable. Some models need modifications, special support features or be split into multiple parts.
With all the 3D models out there and people posting their results, you can just pick the stuff that seems to work and you want to print.

The CubeX and the Makerbot Replicator ones, seem to be the most advanced and user friendly 3D printers and there are pros and cons for all of them. There was no user experience on the CubeX since it was just getting released, but there is a lot of info on the Makerbot, and some of the reliability issues I have read have pushed  me to get the CubeX, despite the Makerbot has more "advanced user" tweaking options and has been around for longer and a big user community that shares experiences etc . which will also happen for CubeX users.

The smaller Cube Printer has been available for over a year and has gotten good reviews for being solid and reliable, so I figured the new bigger CubeX hopefully displays the same quality, which it does so far.

With a brand new product, and as an early adapter I can't expect everything to be perfect right away and was happy to see a quick software update after release with already improvements and added features which I am sure will continue. I am looking forward to hopefully have more "advanced user" adjustment capabilities to get the most out of this solid 3D printer.

It is quite awesome to upload a model or designing a part and see it getting printed or have it printed overnight to see in the morning when you  wake up.   - It's like Christmas every day  :)

I will keep adding to this review or write a new one once I have done some ABS printing and more multicolor stuff.
After trying several ABS prints, I find that without a heated printbed, ABS printing is quite limited due to exessive warping of the ABS material. For ABS printing, I highly recommend the aftermarked heated printbed for the CubeX. See my other post about the heated printbed from GRM products.

Update Nov. 2013:
The hardware of my CubeX has been holding up well. There were a few little issues, but any needed replacement part was covered under warranty.
The cartridges have been troublesome (as you can see in my other posts). Even any defect cartridge is getting replaced under warranty, it needs a long term solution.
The software is improving and works very well for certain prints, but is overall not matching what the hardware is capable off.
The lack of for example, support adjustability, wall thickness adjustability, print speed, etc. limits successful printing capability.
With more adjustment options of course, more things can get messed up too, and I think Cubify is trying to keep it simpler for the user, but this technology is still far from plug and play and different parts often need different print settings that are not available with the standard CubeX software.
So several users are trying to get other slicer software to work with the CubeX, but some knowledge is needed to use those. Search the CubeX user group on Google for more info.
With other slicer software options the very good hardware platform can be taken advantage of without the standard software limitations to produce nice prints.

Thursday, May 9, 2013

CubeX ABS printing

I should finally getting my first CubeX ABS print cartridge this Saturday, so I am excited to try out some ABS printing. Stay tuned.

CubeX Blog Posts Updates

I am frequently updating and correcting prior posts as I am learning more, so keep checking them for updated info.

Wednesday, May 8, 2013

Some more CubeX 3D printed models

Here are a couple more prints with the CubeX.
Most of these are pretty small models or scaled down, so they can be more challenging.