Category Archives: RepRap 3D Printer

Enclosing your 3D Printer

September 27, 2013 Zac Leave a comment

With my 3D printer dialed in and tuned up, I was still having issues with the temperature on the heated bed and parts warping. I determined that this was due to external air currents in the room. I had been considering building a permanent table for the 3D printer and added an enclosure to my design to eliminate the effects of drafts on printed parts. The enclosure is nothing fancy, very low tech in fact. It is a corner framed box made from 1/4″ luan plywood with sliding plexiglass front doors. It has handles and easily lifts off for maintenance and upgrades.

The table is made from 5/4 pine lumber I had cut a few years back when the electric company cleared power lines along the property. It has a full width drawer that slides out fully. I needed a place to hold the tools and parts used to maintain the 3D printer in tip top shape. The small shelf in the back keeps the power supply and other wiring off the floor for better airflow and cooling of these units.

For now, my 3D printer is driven by a computer and it has a nice new workstation courtesy of my good friends Mark and Michelle who donated the computer desk to the cause. I also use this computer for development and programming of other projects like; Tetro the quadroped robot and Filastruder the filament extruder that will feed the 3d printer filament made from recycled plastic, and other cool things I’m not ready to leak to the public at this time. 🙂 Have no fear there will be blog posts on tetro and filastruder as I find the time.

Adding the enclosure required some necessary additions to the printer. First was lights on the print head. I used to not understand why people would put lights on their print head, but now I get it. When it’s running it’s important to monitor filament laydown and in the enclosure it’s pretty hard to do so without the lights. I added three high brightness LEDs aimed at the print area to the left side of the x axis sled.

I used 12V SMT LED light strip which is readily available from online suppliers to light the entire enclosure. The above photo shows the strip attached with a pressure sensative adhesive strip to the inside front of the printer enclosure. The 30″ of light strip provides more then enough light for the enclosure.

Above photos show the effectiveness of the LED light tape. Left photo lights off, right photo lights on. A worthy addition to the printer.

What’s left to do to the printer before it is done? My next steps will involve some changes to the control interface and enclosing the electronics that drive the printer (seen in the above photo). These changes will turn my 3D printer will be a true stand alone machine with an LCD display, control interface via buttons and dials, and an SD card reader. This will eliminate the need to have the PC running or even connected to the printer for operation.

around the house repairs and DIY fixes, RepRap 3D Printer

Using 3d printed parts to fix broken things

September 10, 2013 Zac 8 Comments

Everyone has a bunch of items around the house that are in need of a new knob, button, clip, etc. Having a 3d Printer makes it easy to take care of these small repairs. One might argue that it’s not worth the cost, but is it really? Most parts needed for household repairs only use a few grams of ABS plastic when printed. Given the relatively low cost of the filament, there is no where you could buy replacement parts (even if you ignore gas or shipping costs) at even 2x the cost of making one yourself. I strongly suspect that in the future replacement parts will be printed on location rather then producing extras during a production run, cataloging, storing at a warehouse and then shipping them to a consumer with a broken item. It’s far easier and cheaper to email a part file then it is to deal with logistics of supplying replacement parts.

I have had the same fan since I was in college. It is made by Duracraft, and of the free standing, oscillating type. Over the years I’ve walked into it or knocked it over vacuuming a number of times. As a result, all of the small clips that hold the two halves of the wire fan guard had broken. This was the perfect time for a repair with a 3D printed replacement part. I took some measurements, quickly drew up the part in my favorite CAD software and printed one out. My first version was not quite right, so I made some slight modifications to make it perfect. In my design I included beefing up the strength of the clips by adding a little extra thickness to the part in critical locations based on where the originals had failed over the years. Printing out 5 of these small clips my fan is once again good as new and I am safely protected from the spinning blade once again.

My repair clips for the fan are better then the originals, cost about $0.90 each in terms of filament used, and now my fan has been saved from being prematurely thrown out while it still has many more years of life left in it.

Similar to my Duracraft oscillating fan, I had broken the power button on my Rival High Performance Mixer years ago. I was still using it regularly but while making cupcakes one morning for a party, I realized I was sick of hurting my thumb every time I used my kitchen mixer. I sat down after the cupcakes went in the oven and by the time they were done baking I had designed and printed the white slide button you see in the above photos. It’s ergonomic, comfy and WAY better then the sharp bit of metal that was sticking up prior to my repair. I seem to recall the original was the same blue as the “power plus” buttons on the side but I can live with my white 3D printed replacement.

Once again, a useful household item was repaired at almost no cost for the repair part. I doubt there’s even $0.30 in the tiny button I designed and printed for my Rival High Performance Mixer. I expect to make lots of tasty things in the future with this great little hand mixer.

This last one will make all of my friends happy. My peanut car (aka a 2005 Ford Focus) has had a broken window crank for years. Originally broken on my side I swapped the broken one to the passenger side of the car. I never really had issue with the broken crank, but everyone who rides in my car complains (or at least comments on it). I did buy a replacement HELP! part at one point but it broke after only a short while. I decided it was high time I fixed this as I was in a repair things mood and I drew up a replacement knob for the window crank, printed it out, and installed it. It works better then the original part. It is likely stronger then it as well. ABS is a great material in terms of strength and impact toughness. The original had some flimsy polystyrene snap connector. I used an M4 bolt and washer to attache the knob in my design. Someday I may even paint it black to match the rest of the car.

In closing, 3D printing is not just for printing toys, or prototyping new designs. 3D printing can be used to cost effectively provide replacement parts for common household items. I read a paper recently that the Navy was retrofitting high end 3d Printers that can print in metal aboard all of the ships in the US Fleet. This makes a lot of sense logistically, as they no longer would have to stockpile critical spare parts. I can foresee that companies will someday offer replacement part .STL files directly to consumers to be 3d printed in the not to distant future. With 3D printers now available at Staples and soon to be in every home much like an inkjet printer I feel this day is assuredly not to far off.

RepRap 3D Printer

Upgrading your 3D Printer – x-axis improvements

August 29, 2013 Zac 1 Comment

After my initial excitement of having a fully operational 3d printer waned, I used the printer to produce parts to upgrade itself. Making itself better, stronger, faster than it was before. (How cool is it that the printer can make parts to upgrade itself??) Mass of the moving components limits the speed at which they travel and increase printing time. Inertia has to be compensated for in acceleration parameters as well. In short, less mass equals faster printing. The primary goal of printing replacement parts was to reduce weight of the moving components, the x and y axis sleds. The Z axis moves very little and the mass is much less significant. This post focuses on the x axis upgrades. The above photo shows the x axis sled with side by side comparison of the original (on the left) and the upgraded (on the right) components. The left side is the original proof of concept machined aluminum bearing mounts and cross brace. The right side shows the upgraded 3d printed LME8UU linear bearing mount with a skeletonized machined aluminum cross brace that also lowers the print head slightly.

As you can see more clearly in the above photo, the 3d printed ABS plastic bearing mounts are considerably smaller then the original CNC machined aluminum design. My plastic bearing mount raps around the bearing 20 degrees beyond 180 on each side for positive retention and due to the flexibility of the ABS snap over the bearing with a perfect fit. The plastic mounts remove 18g of mass from each bearing. The skeletonized cross braces come in at 8 grams in aluminum vs 36g of the original aluminum parts. I did print them in ABS at 2g part weight, but they were a bit too flexible and I was concerned with heat from the making them softer still.

The upgrade of the linear bearing mount and cross brace resulted in 128g of mass removed from the x axis moving components. Also the bearing mounts applied a more uniform clamping pressure on the bearings then the CNC machined design, that when over tightened resulted in bearing drag. As is often the case when building something, you design and build using the tools you had on hand. I always planned to replace the machined bearing mounts. My original CNC machined aluminum bearing design was accurate but bulky, ugly, and heavy.

Above is a rendered image of my LME8UU bearing mount design. The mounting holes are tapped M3 after printing and 10mm between centers. Here is a pdf technical drawing showing the dimensions : LME8UU bearing mount technical drawing. I have added the linear bearing mount to Thingiverse.com as an STL and IGES file for others to use. Here is a link if you want to print your own 8mm linear bearing mount for a project: http://www.thingiverse.com/thing:142243

All was not 100% perfect with the bearing mount upgrade, I did not consider the limit switch contact points when designing them. I added a small aluminum plate using 2 of the 3mm tapped holes to solve this minor oversight. Eventually I’ll add a physical feature to the 3d model and print new bearing mounts for the two limit switches. My original purpose in designing these LM8UU linear bearing mounts was as a universal part so that I can use them in the future for other projects.

Along with the weight reduction I moved the wire support to a more centralized location on the back side of the sled. I felt this would help reduce strain on the wires during the repetitive movement along the x axis. I orient my parts when printing such that the bulk of the printing travel is done by the x axis. All in all, these improvements along with other upgrades (to be shared in future posts) have gone a long way to increase my printers speed, reliability, and aesthetics.

RepRap 3D Printer

Things you can print on a 3D Printer

July 21, 2013 Zac 2 Comments

So you have a 3D Printer, what do you print with it? First, a bunch of test prints with whatever 3D model files in .STL format you have on hand. STL is the format used in most 3D printing software. I found a bunch of great files to print at http://www.thingiverse.com/. This post is to share photos of the things I’ve printed.

Above you see my post card display stands. I designed these myself to show off some of my most recent post card collection additions. I love post cards, and have every one I’ve ever received. My dream is to one day, when I’m old and grey, scan them all front and back to then share a lifetime of post cards via a website.

This was an early test print part. It’s a link of cable chain. Cable chain is used to route wires to machine components moving linearly.

I labeled each print with a sharpie to keep track of the changes. At this point I was simply trying to get the machine to print decent layers at slow speeds. I think I’m up to XI or XII now.

The above pic gives you an idea of how the cable chain links work. I’ll post more on this when I’ve added it to the X axis of the printer so you can see it in action.

Maker faire robot printed as a test. I was still struggling with pauses in printing at this stage. Turns out the pauses were caused by fragments of Virus software I thought I had completely removed. It’s challenging using Windows OS to run a real time machine. Eventually I’ll have all of the printing done from an SD card directly on the printer with a small screen and some buttons for an interface eliminating the need for a computer when printing.

I printed this cool Iris box as my first larger print. I had some issues printing and this is where I realized you have to use different parameters for larger prints.

I ended up printing the iris shutters twice. The first set (seen on the right side in the above photos) printed out but because the parameters were not correct they were rough, bumpy, and did not work with the iris mechanism. You can see the second set (on the left) are much more uniform and flat.

Everyone needs at least one Minion. This guy has become my 3D printer mascot.

Above shows the largest part I’ve printed to date. It’s a hopper for my filament extruder project. I had some issues getting it to stick and had a couple of failures. After it passed the half way point I added some high temp tape to hold it down and make sure it didn’t lose adhesion to the build platform.

Above is my nearly complete filament extruder. This will allow me to recycle plastic into filament to feed my 3D printer. I have about 20-30 lbs of black abs waiting to be ground up and fed into this when it’s done. Those are commercial resin pellets you see in the photo. I was testing the auger’s ability to feed the pellets as well as test if there was any jamming at the hopper feed to the auger.

A multi part robot I printed out for my Nephew who is coming to visit me soon. I’m using ABS filament for these prints and ABS is readily solvent welded as well as thermally fused.

For my niece, a hello kitty cookie cutter. It needs a little sanding but this should make some very cute lil kitty sugar cookies. She likes to make cookies and I like to eat cookies so we make a good team.

And of course there are the experimental prints like this propeller where each one is printed with a different parameter. I record all of my experimental settings, data, and conclusions in a lab notebook. Keeping a well organized lab notebook and project records is the secret to project success. This set of experiments was targeted at settings on printing larger thin wall parts. Two conclusions were drawn from them, first the ideal print speed for this type of part and second that reducing the extrusion temperature results results in better print quality. This part had no purpose but a friend who is a HS teacher asked for some parts to use when teaching his students about 3D printing so they are going to a good cause, the education of the future generation.

There are many other objects I have printed, both successfully and less so. I guess that’s enough for my first show and tell 3d printed objects sharing for now.

Projects by Zac

Category Archives: RepRap 3D Printer

Enclosing your 3D Printer

Using 3d printed parts to fix broken things

Upgrading your 3D Printer – x-axis improvements

Things you can print on a 3D Printer

Sharing some of my projects and what I've learned along the way