Printing at Last

Not posted for a while.  Had been waiting for my new controller board to arrive, which is now installed.  Have now got past the testing stage and am finally beginning to print of 3D objects.  However I still have some minor tweaking to get the printer calibrated correctly and also need to install a secondary fan on the Hot End carriage in order to cool of prints as they are being printed.  From what I've read this improves the quality of prints.

Printing is a bit hit and miss at the moment as I am trying to figure out how to correctly calibrate/commission the printer.  Will just need to research more thoroughly what's out there on the RepRapPro Mendel.  Overall though I'm fairly satisfied that I'm heading in the right direction.

Update a few days later...

Used up my first 100m of filament.  Doesn't sound fantastical, but so far I've printed 3 Iphone cases, a snowman shaped cookie cutter, a pair of tweezers and lot's of calibration objects.  In order that my filament does not get tangled as I have to leave on floor I printed out a filament spool holder that attaches to the printer  All the time I'm experimenting with different settings and learning new things as I go along.  Right now I'm printing out parts for a 3D printed actual working clock that will tick!

That's my 3D Printer Project build now complete.  It has been great and I would recommend it to anyone who is interested in making stuff! 

Well, thanks to all for taking the time to visit my blog.  At some point I may post again, but for now all the best.

Jason



Some first prints.  Iphone case at top went wrong!

Broke It :( Fixed It :)

1 Still on Board 1 Pin Broken

It was all going so so well.  I was just at the end of testing the electronics prior to commissioning and something bad happened.  This is a lesson learnt.  Try to identify for sure what a component is before you do something to it.  The last part of testing the electronics is to adjust the potentiometers on the controller which reduce the power to the stepper motors.  The instructions tell you to turn them gently anticlockwise fully and then turn clockwise by 45 degrees I think.  Well, me, with a big pair of long nose pliers turned what I thought to be the potentiometer anticlockwise.  At the time I thought it was little stiff, and started wondering if I was doing the right thing.  The component started to come away a little, alarm bells started to ring in my head.  It was becoming loose.  Too late, I'd broken it.  Of course I was simply forcing a capacitor (not sure if it is a capacitor, but looked like something I could turn) of the board and not adjusting the tiny little potentiometer screw to the right of it. 

Spent ages thinking I could solder this thing back on, but the little leg was only a millimetre and a bit big, and was not easy to offer up, wet the solder and keep in place.  Did manage it once, but then couldn't force the component back on again.

Now a delay to my build.  Suppose I could test all the other bits out, but I'm thinking that maybe I will have to get another controller board or RepRapPro may offer some advice.  Perhaps it's possible to source another identical component or equivalent and solder back.  I don't know.  I've emailed them and dropped a post of on their forum, but as yet no reply.  So am in limbo.

After some thought, a workaround, cool!

A few hours later and I've carefully started to master the Pronterface software.  All connects up fine by USB.  Can connect to printer and send commands.  Interface starts become useful and is no longer just an unknown.  So, full steam ahead.

All Axis's and Heated Bed Complete

Whoops... Previously I had published a post with the above title or something similar and it took me a couple of hours or so to write up.  Got this great new App on the Iphone where you can do what you can do from a phone rather than a PC.  Brilliant I thought, got some text down and uploaded it to my blog area.  At home later I finished the blog and included some decent photos of progress so far.  Also put some explanations in, as I was thinking that I was using too much jargon again.  Even sprinkled in some jokes to make it a bit more entertaining.  Spent some time polishing it off and then published it to for all to see.

Checked on my phone later in the evening using this little app and it was telling me that I still had it in draft form.  Okay then, I don't need that, so deleted the draft.  Somehow that deleted my blog as well!  Never mind.  Lesson learnt.  Here's one photo of the progress thus far.  I'll wait now until I've finished all frame and axis work and write up fuller account before I start the electronics stage the build.

X Axis Carriage Assembly

I've decide not to update my blog every time I tighten a screw.  Instead I will update whenever I've completed a section.  That way I won't bore you too much.

Comments have been made saying that I'm not explaining things simply enough and thinking about it, unless you are familiar with all the terms, some references I make will not make sense.  So then, what's all this X, Y and Z stuff I keep going on about you may ask.  Well, in 3D printing everything works in 3 axis's unlike a normal printer that only works in 2 axis's, the X and Y. For example, looking down from the top onto a printed piece of paper everything is printed in one plane, the X Y plane.  The print head of a normal printer moves about the X axis and the paper itself is moved a fraction at a time in the Y axis.


The X Carriage holds the extruder

When looking at a 3D printer from the front, the X axis is movement from left to right or right to left.  This is done by movement of the actual print head (Hot End or Extruder) which is mounted to the X Axis Carriage and runs along 2 smooth rods.  All of which I have just finished tonight.

The Y axis is the movement of the The Frog Plate which supports the heated bed where the 3D object is printed on. The build of this was described in an earlier post. The heated bed moves front to back or back to front along the Y axis assembly also on 2 smooth rods.

The extra dimension for a 3D printer is the Z axis.  The Z axis movement starts at the bottom just above the heated bed and moves a fraction of a millimeter at a time upwards as each layer is printed.  All 3 of these movements happen at the same time to build a 3D object and are controlled by little electronic motors.

Hope that's shed some light on how a 3D printer works a little.  There's lots of other technologies not covered yet, but I'll try explain what's what when I get to them.



Idle end of X  Carriage cracked

As for tonight's work I have made some mistakes.  First of the X Carriage itself had dozens of nuts, bolts and washers.  Once it had been built I had 2 nuts and one washer left over!  Like building something from Ikea.  That meant I hadn't read the instruction properly and had to review everything I'd done, count all the items and compare what I had made with the pictures on the Web.  Got it all figured out in the end though.

The smooth rods I used were the wrong length.  I had used the smooth rods that were supposed to have been used for the frog plate or Y axis.  Needed to undo those and swap them over.  In the process of me doing so meant re-inserting them back into the X Carriage ends.  Using too much force cracked one of the printed parts.  It's still intact, but I hope I can get away with super glueing back as it is not completely broken and won't be weight bearing when in operation.  Fingers crossed.  I can always print out a new part once the whole thing has been built.

Assembled X Carriage

One last mistake I made was not to de-burr or round off the ends of the smooth rods enough.  As I needed to insert these rods through bearings more than once, they caught the inside of one of them and popped out a couple of the tiny little ball bearings that were inside.  This should not matter too much as all the others are are held firmly in place with the smooth rod inserted.

Y Motor Assembly

The Y motor moves the Frog plate backwards and forwards as you look at the printer.  Was a little tricky as I had there were no pictures showing how to set the belt pulley, but I was able to see how that was done by looking at picture of the fully assembled frame.  I need pictures!  There is a worded description of how to fit it all together, however it's full of unfamiliar component names at this point, so I just figured it out logically from the picture and good reasoning.  The printed belt clamp holders have rough kind of serrated edges on one side and I thought that that was due bad resolution on the printing, but no it was all in the design.  The serrated edges are designed that way to grip the belt when tightened down by the bolts.

The second part of this motor assembly is the little black micro stop switch you can see above towards the top middle third of the picture.  This will halt the travel of the plate to stop it from hitting the edge when moving back and forth.

Finished The Frame

Completed Frame with Y axis Frog plate

Got a couple more hours in on the build last night.  Finished the frame assembly.  Was keen to make sure that I did have all the angles correct.  So it was off down two flights of stairs to the kitchen again, and the flat work surface.  Shimmed up back two legs with 4 bits of paper to get the spirit level indicator correct. Did the plumb weight technique on the vertical Z smooth bars.  I'd done this before and had it mostly right, but now it was off by a mile! My partner uses the same computer room to do her web surfacing, mostly the MSN website (she hasn't figured out how to change home page yet) and browsing for yet more holiday bargains.  When she does this she likes to get comfortable, meaning putting her feet up on the table.  I asked her if she had touched the frame and she said "Oh... yes well, I did try to put my foot through, but then saw that there was a bit of cotton in the way".  That was my plumb line.  Why would she try to put her foot through the frame? I thought to myself.  Anyway, she had only twisted one of the bottom U clamps through 180 degrees.  It was loose, so didn't matter, put it back and all was well again. Politely asked if she could be more careful next time she goes up there.

Smooth rods in and tightened off. The next stage is the Y axis frog plate. Think this is the bottom part of the heated bed support and will have a belt clamp to driven by one of the stepper motors. The motor was put together with it's supports in readiness for mounting somewhere. Next was frog plate, so called, I think, due the laser cut shape in the middle that resembles a frog. This piece was easy to assemble with the bearings and clamp fixings. It was longer to go through all the plastic bags to find the parts that were needed than to build it. The belt will attach to the clamps and is driven by the motor and will move the plate in the Y direction when all is operational.

If you are interested in seeing some time lapse build videos.  Some are short and some are long, but it will give you an idea of how things went together.  They are shot at one frame per second and viewed at 30 fps.

Frame Assembly

Assembly of the frame is now compete

Last night I managed to complete the frame assembly of X Y and Z axis.   This was good because now I could see what the whole assembly would look like. I'd put the some of the nuts on the wrong way round on the screw bars.  I needed to twiddle them off, turn them around and twiddle them (satisfying feeling... twiddling) back on again before hand tightening.  The distance between the plastic parts on the triangle Z axis is 290 mm and 273 mm between the horizontal X and Y axis.  The kit included a handy little measuring template with these various distances marked on it.  I am now at step five the frame assembly. This is the part where you slide in the smooth rods on Y axis (heated bed) and Z axiz (up and down motors).  Now for the important alignment part. The Z axis smooth rods have to perfectly vertical and squared to the X and Y axis.  To do this I shall opt for lengths of cotton and blue tack acting as plumb weights advised by author of the Mendel build instructions.


Down to the kitchen work surface which is meant to be flat as hell.  Cotton, Blu Tac and a spirit level used here. I'm happy as I can be that I have now got everything square and level.  Not shown in the picture is the smooth Z rods.  The Z rods will be where the two lengths of cotton are.