Late Updates

Sorry for the late updates, I haven't been updating this blog as much as I should, I have been throwing updates to the parts downloads themselves at http://www.thingiverse.com/thing:981105 and http://www.thingiverse.com/thing:990244

Check them out.

ROB-O Junior frame build

  And it begins......

  I picked up so series 10 aluminum extrusion from Amazon which is 1" x 1" square, I see a lot of people using series 15 or 20 (1.5" or 2") aluminum but after building my frame I have to say that they are mega overkill, I could stand on mine and not flex anything at all, maybe if I was going to make a printer twice the size.

  The t-slot aluminum is awesome to work with, it cuts pretty much like wood as it is a soft metal so it cut very nicely, they make nuts that fit into the slots and slide around and so you can position them anywhere along the channel but they are expensive $9 US for 25 and then $15 shipping which is outrageous so I used M5 nuts and bolts, I probably should have tried M6 but I couldn't find any at the hardware store and didn't want to buy 200 of something that I had to grind the edges off, all I could get at the hardware stores was 1/4" (grind it), M8 (way to big) and #8 screws (too small) so I went with something that I knew would grab but didn't need to be ground but they are too small to touch the sides and so would spin and would flop around in the channel so I printed some holders for the nuts, there were quite a few out there already but they all have the flats of the nuts parallel to the flats of the channel and they don't overlap that much so I could see over tightening the screws and it pulling out of the channel so I made some that the nut is turned so that it grabs as much of the channel as possible, I also rounded the edges for several reasons:

  1. Printers move faster along curves than they do corners.

  2. When printers do corners they can leave extra plastic as it pauses at the corners (on mine anyways)

  3. When printing without fans (I was using ABS as I have lots of it) the corners of things angled up REALLY start to angle up and if it comes to a point it will cause a bulge up at every corner.

  4. Less plastic made them print faster.

  I wanted some extra support in the corners of the brackets so I connected the tops then thought they would look better curved, then I was looking at it thinking "what a waste of plastic" and thought about cutting a triangle out but it wouldn't look very good and would give three sharp edges to crack at so I decided to cut circles out, it lessens the plastic used, is extremely strong, and looks pretty cool.

  I have a bunch of bad plastic from 3D Solutions, Hatchbox and others so I have been using it to print the parts then once R.J. is up and printing then I will reprint all the corners as it will be higher quality prints and in the colors I want, and may do them dual color, maybe black and silver, instead of wasting the plastic parts I have I will then give them to a colleague at work to build himself a printer then he can do the same and reprint them.

  Here are all the parts that I have cut or printed to make the frame and them being put together.

  The first corner applied.

  All put together.

Long overdue update

  I apologize for the silence the last few months, I have not been in a place where I could do much with the printer lately but I didn't let it go completely I have been designing replacement parts I have a new X carriage built and printed that should work nicely and have been working on the final version of the Y carriage/X carriage holder, I just made a few (I hope) final tweaks to it I just need to print them out now.

  I was going to rebuild the printers CoreXY mechanism and bought all the parts I needed to finally increase it's size to what it's final size was to be, a 2000 mm precision hardened steel shaft to cut to the right lengths, CoreXY plate water jet cut, aluminum bed (the middle of the plate), second head etc. but what if I got it all ripped apart and realized something was printed wrong and I doubt I would be able to get the old parts back together in a decent fashion to print again as it took me a week to get it to work last well time so I decided to buy some t-slot aluminum extrusion and make a frame out of it and put all the new parts into a second slightly smaller printer.

  I will use the "Bubblegum Printer" as I have been calling (held together with bubblegum and bailing wire) to make the smaller printer and then use the smaller printer to rebuild the larger printer.

  I have the aluminum and I SO wished I would have used it on the original printer, I wanted to but I couldn't find it at a decent price and so went with the L shaped angle aluminum and am so kicking myself, I finally found the extrusion for a decent price and it is cheaper than what I paid for the angle aluminum, ROB-O Printer is so wobbly without the sides, and I mean REALLY wobbly even with four rivets per corner two on each side and bracing, even with the sides it can still flex, I put the extrusion frame together and what a difference, it is rock solid and has no flex whatsoever it doesn't budge a fraction of a millimeter and is so nice and square, I used corner pieces I printed on ROB-O and will reprint them in the final color when it is up and printing as it will print SO much better.

  The X and Y carriage designs I have made are so rock solid and have zero play, zilch, none yet glide very smoothly, I had worked them out and printed the final X carriage (I hope) and some test Y carriages in may but have not had time to come back to them until now.

  I am going to call the new printer ROB-O Junior until/unless I can come up with a better name, I am horrid at names. ;-) It will have a build area of 9" x 9" x 15" tall, of course that can change as I build it as it is a work in progress, watch for build posts.

The Sapphire Rose

Could it really be the Bhelliom? I wish...
The design of the rose was by  PROCOPRINT3D at thingiverse.com he did an awesome job.

A Man that loves a Woman gives her a rose, a Geek that loves a Woman MAKES her a rose.

And with a little clear coat:

Lit up.

Jewelry Tree

I made Heather a jewelry tree last night, I wanted to link the model and give credit to the person that designed it but for the life of me I cannot find it on thingiverse.com now, the zip file was called "Tree of love" but I cant seem to find it.

Sanding glass

  I have been having a hard time getting things to stick on the glass, I was getting tired of using glue sticks, when it did work it made it almost impossible to get the part back off.

  I read that sandblasted glass beds work really well but I had no sandblaster to use on the glass so I had an idea of sandpaper and it worked well it took a bit of elbow grease, I should have broken out my palm sander and may do that for the other panes.

  The parts stick now, and how, if the glass is hot I cannot remove the PLA plastic at all, I tried... but as soon as it cools off the plastic pops itself off just like ABS does (ABS massively shrinks when cool PLA doesn't) I have not tried printing ABS on it yet but I bet it sticks just as well, whats more is that the printed part is still as smooth as glass even though the surface has been sanded, the scratches are so fine that the plastic does not pick it up.

Extending the bed

  I finally have the longer shaft to extend the bed, I bought a 60" long 12mm shaft and cut it into three peices.

  I got the old bed apart and found my issue with my bed never going to the same spot when I tell it to go to the 0 position, the right bearing had over a 1/4" slop in it, it was really bad, the guide shaft was really flopping around bad so I replaced it with one that I bought for the front corner for when I expand the bed size. 

  I put everything back together and when it would move up or down the left side would jam and skip (slam violently back level) as it moved up and down, I figured it was misaligned so I designed some new parts that will hold the shafts level with each other, I tried to print it out and it completely went wrong so much so that it jammed itself so bad that the power supply shut down.

  I was having a hard time dealing with some other stuff so I just shut it down for a few days, when I brought it back online and went to readjust the left guide shaft I could hardly move the left shaft, I really had to fight it to get it out of the bearing, when I finally got it out the bearing steely balls went everywhere, the bearing was destroyed so I had to replace the left bearing as well.

  I am glad I have been buying the parts I need to upgrade here and there so I had them on hand.

  The aluminium casing that holds the bearing is supposed to be universal so I thought I would slide a new bearing into the casing and be happy.... nope the hole in the casing is just a little smaller than the standard bearing size, figures, cheap Chinese made crap. That's what I get for trying to save a buck.

  At the same time I decided to put a bandaid on the current bed, the heated bed is just a thin fiberglass circuit board with a heating element pattern etched into it, since it flexes so much it is hard to level the bed so I saw a pain pallet at Harbor Freight for around eight dollars that was plenty big enough so I cut the rounded part off, cut a spot for the wires etc, got it under the circuit board and all was happy for a day or two until.... 

  I had to drill two holes through the heated bed to mount onto the wooden base as the wooden base isn't quite long enough and it was really close to the main power traces on each side of the board, I had no problem but the washers under the screws had ended up wearing through the epoxy on the board with all the bed adjustment I had been doing and it was now making contact with the main power traces on the bed, add a metal plate underneath that the screws go through and it created a short that every time I went to heat the bed would shut down the power supply, when I figured it out I put some non conductive material under the washers (cardboard) and it is good to go and is happy again.

  I now have the printer up and running after a week of it being non functional for a week and I am now able to print something 20" tall so I am happy with that.

  I think my next steps will be to replace the XY carriage and then replace the bed with the full size heated aluminum bed.

  

  More later.

Aut bed leveling probe idea

  I have already done a auto bed leveling setup on the current printer but it is not that great, since it is servo driven it is really far away from the nozzle and for some reason the firmware is having issues with it being so far away so as part of the new configuration of the XY axis mechanism I am incorporating a new auto bed leveling probe into the carriage/head design.

  I have some piano wire that I use for push rods in my model airplanes and I was goofing with a piece when I noticed that if I drilled a hole up through the heat sink of the hotend then I can have the probe really close to the nozzle, the wire is metal and is passing through the heat sink so any heat it picks up will be dissipated by the time it gets up to the top.

  So my thinking is to have a plastic collar at the top that the wire goes through and locks into that has a tab on one side to break the light beam of an optical sensor to be triggered, that will be encompassed in a spring loaded casing that when deployed a servo will push it down into place and then let it spring back up when it is done.

  More on this as I go and get it figured out.

Noisy Cricket from Men in Black

A fellow 3d printer junkie at work brought in a Noisy Cricket to work and I was telling him how important with PLA the fans were, I brought it in to work for him to have but he wasn't here so I am throwing up some pictures of it.

It needs a bit of sandpaper but not bad, it was printed with white PLA with 100% fan speed, nozzle size 0.3mm layer height 0.075mm, heated bed set to 70c
The noisy cricket design was found on MyMiniFactory.com and was designed by Darras Bertrand

Mounted the display finally

I finally quit procrastinating and printed out a holder for the display, it took me a bit to find one I liked as I didn't feel like designing my own, I settled on this one by Scott Mayson it worked out really well, before I installed the board into the mount I glued a piece of clear plastic that I use for windows in my model train buildings as a scratch/dust shield over the display.

It is SO much nicer to just twiddle the knob and push down on it to select things instead of picking it up, holding it in one hand running it with the other, setting down on a screwdriver, or the metal edge of the printer and shorting it out etc.

Thanks Scott for the cool design.

Cats, Hair bands, and Bottle Openers

Some things I made for Heather this weekend, I made her some cat figurines, a hair band, and a couple bottle openers, one for 2 liter bottles and one for gatorade bottles.
The hair band was designed by Jensa and is found on youmagine.com

Cat treat ball

I printed a treat ball that as you knock it around a treat falls out, I went to take a picture of it together but I didn't do it right off the printer and now they have hid/kicked it who knows where.

It prints in two halves, you line up the notches and snap it together to make the hole.

Ruby likes the treats but doesn't get where they are coming from.

Raven knows what to do with it though.

Ball inside a ball for the cats

I printed a ball inside a ball for the cats to kick around as a toy, Raven loves carrying it around and knocking it around, every time we try getting a picture of it she drops it.

Since it was just for the cats which means that I will eventually step on it in the middle of the night I just did a rough print and didn't really clean it up much.

It prints support material to make sure things don't sag.

Keeping out the moisture

Plastics absorb water believe it or not, Nylon is one of the worst, then ABS, then PLA, you can dry out the ABS and Nylon in the oven or a food dehydrator but the PLA tends to break down after the moisture absorption and then drying it out and printing, according to the studies I have read if you use PLA that has absorbed moisture that you only get about 33% of the strength out of the plastic that you would have if it was kept dry.

Now I don't mean soaking it in water, I am talking about it just pulling moisture from the air, I stole the cake cover from on top of the fridge since it has been almost 5 years since we have made a stacked round cake, then made an adapter for the side of it to connect a bowden tube between it and the extruder, and then from the extruder to the hotend so the only place it can pull moisture from is the opening in the extruder where it never sits long enough to pull any moisture from the air, I would have to let it sit without printing anything for weeks for it to affect it and it would only affect that small section, but without this system by the time I was 1/3 through a 2lb roll of filament that the rest of the spool would be pretty wet, nylon only takes 2-3 days to absorb enough moisture to affect the print so imagine it sitting there for a month as you are using the roll.

A mounting bracket for a moisture absorbent gel pack that I picked up from amazon, when the beads turn green you bake it in the oven until they turn orange again to recharge it, that will absorb all the moisture in the spool chamber.

Mounted in the top of the lid.

It is a bit overkill size wise but oh well, it will work well, I liked it for it's clamps, my original idea was an ice cream bucket but it was not quite big enough.

So the plastic filament is pulled through the tube off of the spool.

This is the extruder that pulls the filament from the spool and pushes it to the hotend, this is where the bowden tube really comes in, it acts like the brake/shift cable on a bike, both ends of the tube are attached securely then that allows the plastic to be able to be pushed through and be guided by the tubing allowing the hotend to move around and still be fed plastic.

I used a zip tie to hook the bowden tube to my wiring harness because other wise it will move/flop around while the plastic is pushed and pulled causing slop, it is the same reason your brake/shift cable on your bike is attached to the frame every so far.

Then it pushes the plastic down through the hotend, the fan keeps the upper portion of the hotend cool as you do not want the entire thing hot just the tip, if the plastic starts to melt higher in the hotend then it should then it starts to jam and clog, the aluminum block you can see under the fan that has the two red wires going into it is the heater block, that's the section that you want to get hot, that and the tip, then everything above that is to be kept cool if you want optimum performance.

Height test

  I decided to try putting the printer through it's paces and see how low it could go, I took it down to a layer height of 20 microns or 0.02 of a mm, so that means that to print something 1mm high that it will take 50 layers to get up to the 1mm.

  I printed these with a 0.3mm nozzle, I should have swapped it out for my 0.2mm nozzle, I may repeat the test again with the smaller nozzle just to see how it looks.

  With  the setup I did you could not see the detail with the naked eye as it was too fine, in fact I had to give it a black ink wash to get all the texture of the feathers and the lines in the log to be visible and still I had to zoom in all the way to see the detail, I didn't crop the picture because I wasn't smart enough to photograph it on a dime or anything so I wanted my index finger that is behind it visible just to give some sort of perspective.

Filament cleaner holder

I bought some foam filament cleaners but no real way to hold them etc. so I made a holder for it that one end will slide into the inlet of my extruder and has a spot to screw in a bowden adapter (more on that later)

I am putting up a bunch of pics to show how it comes out with support etc. so the process I go through when I pull it off the printer.

Extending the display cables

The display I bought for my printer came with reasonable length cables but they weren't long enough for my printer to reach the back so I took the ends off, took an old computer hard drive cable and made new cables so it can reach the front.