I ran across something that I am seriously considering printing – a 3D printed lawnmower that looks like a Roomba. The mower is printed using a simple design and uses Arduino boards that are easily programmable. I’m not a great programmer, but I am assured that the Arduino motor and board programming can be tackled by a beginner to do simple path and reset maneuvers. The body and wheels and even the blade seems so simple and the looks of the mower, dare I say it – sideswipes you since it is kind of cute. Of course it is a lawnmower, so remember that this “cute” also has a blade that cuts things with so appropriate caution should be taken when starting this project.
I ran across the notations on the Ardumower on several websites and the concept was developed by a German aeronautical engineer (there is definitely a pun or two here; rocket scientist cuts a new path, or even rocket scientist mows down traditional lawnmower, etc., etc., etc.)
Andreas Haeuser has several designs that he has done in 3D printing, but the lawnmower really caught my attention. Perhaps it is because I really hate mowing in 100 degree plus heat during the summer or maybe because I like the idea of building a tool that saves me labor by using a 3D printer. The best of both worlds – cool 3D printed application and saves me sweat and time – looks like a winner of a project.
In looking for some YouTube videos of the mower running, I discovered that there is a whole group of remote control and automatic lawnmowers out there that have been 3D printed. Some of the designs look a little iffy for the tough conditions demanded by my large yard, and most require the perimeter wire method of controlling the area to be used. However, there are some users that just simply put down a couple of 2” by 4” boards across areas where they don’t want the mowers to go and set the devices for bump and change direction to get the lawn cut.
These mowers are supposed to do the work while they relax. Note that paths that the mowers cut is a bit more random that you get with a human powered mower, but since they are supposed to do the mowing a few times during the week, the patterns are trimmed out as the mowers work over time.
Some designs use metal blades that they get from hardware stores but I like the idea of using a 3D printed blade with the hope of avoiding cutting off my sprinkler system heads in some areas that the surrounding dirt has been washed out by the downpours in the area recently. And I think that I can use a printed blade that has some weight reduction features to cut down on the amount of materials used while actually giving the blade better reinforcements and impact resistance.
My husband, who patiently nods his head at most of my ideas on things that we could print, got interested in this application and actually made the inquiry of how much materials it would take and how many parts we would have to print to make one. So, I think that he is considering the merits of experimenting. But in the meantime, I’ll hang onto the riding mower and put off that purchase of the hand mower just so he can buy into the concept…
If you would like to see more information on similar lawnmowers done with 3D printers – visit YouTube and see the videos (there are over 200 of them) regarding: “3d printed automatic lawnmowers” If you would like to learn more about one of the most popular printers to do these type of lawnmower parts and more, visit our website at www.engatech.com/products. I would suggest taking a look at the uPrint and the Dimension1200es machines as well as imagining all the things that you could do with a printer.
I am always on the lookout for 3D printing in unusual situations and in conjunction with National Maker’s Week this past week; I was looking at the Smithsonian’s 3D printing site. I have to say there are definitely some things that I want to print out from the site including fossils, statues and more. But what most intrigued me was a 3D rendering of Abraham Lincoln.
The Smithsonian has two life masks of Lincoln that were donated by the families of Clark Mills, a sculptor form the 1800s. The family donated a casting of the “life mask” of Lincoln to the Smithsonian in 1811, and this particular mask was done shortly before Lincoln’s 56th birthday in 1865. Life masks were a common practice done in the mid 1800s to showcase the face of a living person.
Lincoln always strived to be visible to the public during his time in office, and this is shown in the worry lines and gaunt features in the mask.
What was interesting to me was how my reactions to this type of portrait of this incredible leader were very intense. I am used to seeing pictures and paintings of the great leader who had such an important role in American history, but I had not seen the 3D scan of the President before. The 3D scan made him very human, very tired and very real to me.
Looking at the picture of the scan, I thought of my own grandpa. He shared Lincoln’s bony features and somewhat tired demeanor and I thought about how the Civil War must have changed Lincoln in so many ways. Compare the look on this 1865 mask to one that was done earlier in Lincoln’s life.
Volk was a sculptor who was doing a statue of Douglas and wanted a “matcher” for Lincoln after the famous debates. Lincoln sat for Volk in 1860 when his political star was rising but prior to his run for President. For a week, he went to Volk’s studio and sat for a plastic casting to be made of his face, in between court dates where he was the attorney working. This was before he rose up to be a national politician and had not been nominated for a presidential candidacy.
In five years, Lincoln aged so much. The above image is a 1917 copy from a bronze casting given to the Smithsonian in 1888.
I encourage you to explore the site at http://3d.si.edu/browser and find out a bit about the models and technology. There are STL files to download and information to be shared. Check on the last view in the series below – so life like.
I’m been a bit nostalgic for my days of relative leisure as a child with building blocks, Lincoln Logs and Tinker Toys and what came to me was that I’ve always been a maker in my heart. My all-time favorite toy growing up was Tinker Toys and spent hours upon hours with the stocks and couplers making everything from full size pedal cars to fantastical wings and buildings. I didn’t’ have rules on what I could build and what it was supposed to look like, but all in all, the structures went up, the cars were created and the “stuff” fueled my imagination and house with all sorts of objects.
I grew, and in a few years graduated to my first industrial arts course in junior high and the joy of drafting. Mr. Murray was a great teacher as we $learned about the details of drafting, how to show hidden features, putting down to paper an isometric view in addition to standard front, side and top and if needed back view. He explained us the need for careful notations on scale and units, as well as how to add details and views on features that needed an “exploded” inset drawing or even an additional drawing. I loved that class with all the things that we did ranging from drafting to fabricating plastics parts (I still have the acrylic candle holders and console bowl I made) as well as leatherwork, simple soldering and more.
From industrial arts we moved up to vo-tech classes in high school which at that time were a required series of courses that all students in the high school took. Ranging from welding to typing and culinary arts, those courses help many of us have part time jobs in college and after school as well as kept our education grounded into the workforce. I thank heavens every day for a well-rounded education in my small town and the dedicated teachers I met. I actually used my set of Tinker Toys to make a model for a public speaking class once. But, when my parents were cleaning out the misc. items before they moved to what would be their last home, the Tinker Toys finally were given away to another family with children. I didn’t think much about it then, but I missed those worn sticks and wooden round couplers years later when I was trying to explain a design with an interior feature to a co-worker. By then, CAD was mainstream to manufacturing and everyone had abandoned drafting and the drawing for electronic files and 3D views.
But then the reality of always using an electronic drawing came home to mass production – mistakes happen. Hidden problems were not as apparent in an electronic drawing or even a 2D hard copy drawing without having a physical model in hand. Hence the 1st article requirement was born. The 1st article was required on many projects where a physical part had to be produced first before high volume mass production could start. Hugely expensive, since the production part had to be tooled up, the 1st article became the dreaded stop to development and commercialization in many new parts because of the delays and the resulting “engineering changes” after the review. I remember the anxious days of review and holding my breath as a committee looked over, measured, evaluated and then signed off. As an engineer and application specialist, I used to hope that marketing didn’t review because they ALWAYS wanted more bells and whistles. The additional features from marketing meant an engineering change, more time, retooling and drove the tool costs to the sky.
Then prototypes using SLA, SLS, FDM, urethane castings, and more came about. Design reviews were so much easier and collaborative manufacturing became the normal mode for new projects. Reviews of what the part would look like, how to tool for features that could be a problem, agreeing on designs, compromises on details – all of these areas of communicating and review prior to high volume production were now enabled and normal. We took sturdy prototype parts beyond design reviews to functional testing for wind, handles them in focus groups for marketing, used them in trade show mock-ups, traveled with them for sales samples, and took 3D Printing with hybrid manufacturing/machining into new territory where legacy tech and new tech made money.
Enter the Maker Movement – where people wanted the power to make pieces and to indulge their imagination by making a physical part using 3D printing. A whole new group of participants got to use tech and creativity to do one off designs, creating new ways to satisfy needs and manufacturing low volume product without expensive tooling. Those opportunities have continued to grow and printers for the hobbyist continue expand. You only have to look at Kickstarter, attend a Makerfaire to see so many low cost Maker Printers. In the meantime, The President includes 3D printing as an emerging technology and the industrial arena sees prototyping and design verification via 3D printing is now being required by many industries and markets.
But to me, it all really started with that cylinder box of Tinker Toys. We created, we built, we tore it up and rebuilt and then we did all over again with Tinker Toys. That low tech that we never saw as a path forger would evolve to a 3D printer used today. Overall, the basic purpose still remains the same between the Tinker Toys box and the 3D printer – to express what we can imagine with a physical part.
And you know what – I never really did outgrow Tinker Toys. Occasionally I’ll see some at a garage sale and you can’t help but start messing with the pieces. And just like 3D printing, you can’t help but think about what you want to do with the technology.
Engatech hosted a plant tour and presentation at the Coleman Associates/HTC site on the 10th in Houston Texas. The event was full with standing room only. That led me to think about other times we have done “outside” events and reflect on trade group meetings where we have done plant tours. Overwhelmingly, plant tours are the most popular event that local interest groups hold. Having gone to my fair share of them, I wanted to get some background on why we all frock to going thru a plant with a group when we wouldn’t be caught in the same room with many of the attendees at these events on a normal day. So let’s go over some of the science behind this.
Per the Harvard Business Review, in general there are three reasons people like to take plant tours.
“There are three primary reasons for taking a tour: to learn, to assess, and to teach. Although those objectives overlap to some degree, they lead to very different types of tours. Learning tours are undertaken by people who believe that an operation has a feature or an ability that is valuable; they want to find out precisely what that ability is and how it works. Most often, the goal of a learning tour is to bring back the knowledge acquired on the tour to replicate the capability. Assessment tours are undertaken to determine how well a plant is doing either along an important dimension of performance or in terms of its ability to fulfill its role in the company’s operations strategy. Teaching tours are undertaken to pass knowledge from the visitor to the plant being toured. The three types of tours demand different questions and focus on different parts of the site.” (Upton, Harvard Business Review.)
The most plant tours are the one where I go to a plant to learn about a capability and to interface with knowledgeable experts at that site. This allows me to determine whether the technology is something that I want to consider without identifying myself as a prime target for a pitch. It is a relatively risk free way to doing a “look see” without having to interface with a company’s sales department or give away too much information when I am evaluating. The same reason that I take plant tours applies to why I go to the Texas State Fair and look at cars (for out of state readers – trust me on this one. If you go to the State Fair of Texas, which is the largest state fair in the USA, you want to see the car displays.) By going to a “display” I can see the tech, access the information in a risk free environment where I am a part of the crowd, and get to find out more info and even ask questions without being singled out.
So why does being part of a group seem popular in assessing tech? Because you can ask tough questions and the answers are perceived by the recipient as being less biased and more truthful in a group setting away from the “sales call.” I can ask by-standers and other attendees their opinion, perhaps even get some insight that I can’t get from the literature or a website. Often I can gather tribal knowledge about tips and techniques on hardware or in use processes on the plant floor from tours plus get to observe the comfort of the operators when they are using the tech or software. Plus I can do this without as much of an influence from the vendor on what answers I am being given or what I observe.
This shift goes along with the shift in sales development seen during the past 10 years as internet searches become the preferred means of gathering information versus face to face meetings and trade group conferences. Going to a plant tour offers a chance to go behind the scenes a bit to find out how the tech works in real life and get reviews from users all at once. The current thinking about the sales process is that prospects have gotten over 80% of the information used in making a buy prior to the final transaction and the trade show, showcase, plant tour and internet search are all part of the prior research. Prospects now are better informed, have a better idea of the features and benefits prior to a sales call, and want specifics on performance, pricing and solutions before they interface on a one to one basis with a sales professional.
To get in touch with our sales professionals – look at our website and call our offices. 866-499-7500 or contact firstname.lastname@example.org. We do our homework so you don’t have to worry about all the details. With our local base and community ties, we understand the local manufacturing environment, issues, and want to help.
Next month Engatech is sponsoring our Houston 3D Printers User’s Forum on July 19th from 8:30 to 11:30 a.m. at the New Horizons Learning Center in Houston TX. I wanted to give you a little background on how we set up the timing and speakers, plus give you a few details, and finally, why going to the meeting is a good idea.
When I first starting developing the 3D Printer’s User’s Forum (also known at the 3DPUF) I looked at the trade and seminar events for 3D printing that were on the national and international stage and reviewed what each of the events contained. Overwhelmingly each event, ranging from AMUG to Rapid to TCT, had a large amount of educational content as well as the opportunity to network with peers and vendors. The events were and are great, and they give a lot back to attendees including some of the best networking I have experienced. (I absolutely suggest going to AMUG or RAPID if you can.) However on the downside, each event costs a lot of money to attend, requires travel with hotels and meals, plus a large time commitment. Going meant you had to be away from your normal work for days. The investment on the part of attendees is huge.
Looking at the outlay for these large national meetings, I started exploring whether there were local or regional groups that did 3D printing educational and networking events in the areas where Engatech serves. While I had started a couple of Meet Up groups to give people a chance to informally socialize and compare notes on 3D printing, the Meet Ups were mostly social groups loosely organized and most members were not users as much as just interested in the tech. In polling clients there was definitely an interest in a more technical program with “user conditions.” Potential attendees didn’t want to travel to a hotel, the event needed to be short, focused and inexpensive and no more than a day. That sounded like a good blueprint for the basics. I got to work on making the vision happen.
I came up with the 3DPUF. While the 3DPUF is not on the scale of an AMUG or RAPID, I and the Engatech team strongly believe that being a 3D printing leader in the region means also showing the way for the kind of discussions and sharing that these meetings represent. Engatech sponsored our first 3DPUF in March in Dallas Fort Worth as a “prototype” event to judge response, examine what went well and how to make the program even better. I was pleased that the Dallas attendees gave us outstanding reviews with a couple of suggestions on the structure as well as topics. With those changes in mind, we started planning 2 more of these educational and technical events – one for Houston and one for the Oklahoma/Northwest Arkansas communities.
The programming and topics are those which have been requested by users. Included in the Houston event will be 6 speakers on 6 topics and they will cover information that attendees will not be able to hear anywhere else. Included will be sessions on “Change in 3D Printing; Trends and Market Reactions,” as well as a comparison of basic differences between processes. Other presentations will include: “Materials and Machine Selection”, “Scanning and Converting Data to 3D” files, expert tips on Catalyst and Insight for FDM, using free on-line resources for file creation and conversions as well as new machine and materials from Stratasys. Of course part samples will be available and a light breakfast will be served for pre-session networking.
If you would like more information on the Houston 3DPUF and to reserve a seat click here.
We anticipate that the event will be full, so don’t hesitate to register. I am also lining up speakers for the Fall OK/AR event, so if you want a topic, don’t just think about it – drop us an email with your suggestion. Have an area that you are an expert on – give me a call and let’s talk. You can send suggestions to email@example.com with the subject line “3DPUF topic” and we will see about lining up experts and more speakers.
As promised during last week’s blog posting, we are talking some more about thermoforming tools produced by 3D printing.
A 3D printed thermoforming tool can take advantage of Stratasys build style to build in the vacuum channel and eliminate the need to drill out pin holes and vacuum feed areas for tooling. So you have the option of building in several ways to make the tool. Each way has some advantages but each is going to be different.
If the part needs to be fairly smooth on both the outside and inside of the shape, using a solid surface with a more traditional hole pattern where the material is drawn down by the vacuum until the tool may be the best bet. The part build style can be modified to have a spare build interior to maximize the draw (vacuum sucking the plastic sheet against the mold) while keeping the traditional solid surface. The holes can be built in by the use of the CAD program to the surface so that the need for post build finishing and drilling is minimized.
For addition, modification of the surface and fine tuning the vacuum, (as an example for areas where the sheet is difficult to be drawn into a crevice feature) the area can feature more holes in the solid surface walls. In some cases, the tool can be built with no skin so that the sheet draws down onto the open lattice surface where the part is open. This technique Is particularly useful when using a vacuum table for a quick prototype of the shape or for thin gauge applications for food packaging. The ability to pull the vacuum can be modified by using different sparse build styles and in some cases having an internal channel for vacuum channeling. There are many academic papers regarding the design of 3D printed vacuum forming tools, numerous white papers and technical bulletins that speak to design and “how to” tips when developing these tools.
Whether the choices are to create the tool with a solid surface and designed in holes, use sparse build on the interior, have a built vacuum manifold in the bottom of the tool, or to do a simple shell with holes, the possibilities of using 3D printing is endless in this application area. A couple of notes of caution, food packaging including clamshell disposable containers that are thin guage thermoforming may be subject to FDA registration rules. When In doubt on whether your application should be registered with FDA such as blister packs, thin gauge thermoforming, disposable food containers, or cosmetic packaging, always consults with experts on packaging regulations.
In general, thermoplastics sheet used for thermoforming can be used with any of the tools printed from the filaments that come from the Stratasys standard stock. For even more detail and glass smooth surfaces, PolyJet tools can be used with build in vacuum channels and pin holes.
For more information about thermoforming and how 3D printing can improve your bottom line, contact Engatech at firstname.lastname@example.org or call our offices at 866-499-7500.
Often the terms of vacuum forming and thermoforming are used interchangeably but the processes may actually be different for different professionals. In general terms, thermoforming refers to any process where the plastic is in a sheet form,is heated to soften and then placed into a mold. Thermoforming is a generic term nowadays and usually includes vacuum forming, pressure forming and twin sheet forming to form a coverall type of generic molding.
Within each process there is an incredible amount of tribal knowledge and tips and tricks; too much to cover in a blog posting. As an example, the “art” in developing a good thermoforming process may involve knowledge of snap back boxes, pre heats, female versus male molds as well a large scale sheets, draw down ratios, custom heats and more. Because of the complexity, we will stick to the basics in this blog posting today – vacuum forming and pressure forming 101. We will leave twin sheet thermoforming for a different time.
Vacuum forming is taking a sheet of thermoplastic and heating it up to soften it in preparation for molding. The softened sheet is positioned over the mold in preparation to be sucked down onto the surface of a mold. Afterwords, the formed sheet is removed from the mold, allowed to cool and then readied for further finishing. The product is trimmed and any secondary operations are completed prior to shipment.
In pressure forming, the sheet is heated and positioned the same as in vacuum forming, but a second piece of tooling (or box as some call it) with positive pressure is used in addition to the vacuum to push the sheet into the shape. Secondary trimming and additional operations are the same as in vacuum forming. The softened sheet prior to shaping may be stretched prior to the operation in order to get a better wall thickness distribution particularly in areas where the sheet will be stretched over the mold.
Each process has advantages. In vacuum forming, the pressures are lower and the overall costs of molds and set ups are usually lower. The process is ideal for larger parts and runs of less than 10,000 pieces.
Pressure forming on the other hand allows for more detail and surface texture to be added to the resulting part. Some claim that the walls are more uniform with less thinning in corners. Differences in cost are highly dependent on the processor and equipment.As far as which process is better for each part that is mostly a factor of design.
One option to consider in either process is using 3D printing to quickly produce a mold. FDM 3D printers allow you to choose your part density and by selecting a sparse style you can 3D print a prototype mold/short run mold quickly & cost effectively. This “quick to completion mold” opens up opportunities for low volume production, quick turn runs, verification of design and custom vacuum patterns for hard to draw areas in the tool.
Another aspect of using 3D printing is building a pattern for a traditional aluminum sand cast thermoforming tool. The pattern can be scaled up easily in the printer software to compensate for the shrinkage ratios as well as eliminate much of the hand work and polishing needs. With fewer skilled pattern makers working today molders need to find alternatives to patterns made from wood or resin board.
3D printing is the next stage of mold building evolution. Design moves from concept to CAD to mold directly using a 3D printer. This month we will be exploring thermoforming using 3D printing as well as blow molding tooling, but if you need to hear more NOW, we have a couple of options for you. Tune in for our webinar on June 9th at 9:00 where we will do an overview of vacuum forming and blow molding tooling done with 3D printing. You can register here: https://attendee.gotowebinar.com/register/8238370521790898948
You can also contact our offices for links to white papers, technical papers and case studies. Call 866-499-7500 or email email@example.com and we will be happy to share information about this technology with you.
Rapid Prototyping Remains the Largest Use of 3D Printing Since the 90s.
Engatech Application Engineer Barbara Arnold-Feret summarized the use of 3D printing in the 2010s as going “back to the future” but also sounded out new paths for the technology at the DFW “3D Printers and Pastries” breakfast held this morning in Grapevine TX.
She presented to a small group of industrial users of 3D printing, where she detailed that 3D printing remains the technology of choice in developing rapid prototypes of new design.
“Over 80% of all uses of 3D printing remain in rapid prototyping, where the technology is used to prove out design, fit, form and function. While we are seeing growth in tooling and end use parts, the first parts usually printed on new machines are to prove out a design or new idea.” – Barbara Arnold-Feret – Engatech
Citing new machines and materials in the market for 3D printing, she noted that the industry continues to look for faster production, stronger and more durable materials while lowering the cost of making parts via additive manufacturing. She said the recent introduction of Carbon’s and HP’s new equipment has caused speculation within the industry watchers on what the next move will be for leaders such as Stratasys.
Problem: Support material was not printing.
Background: A Connex 350 machine continued to have failed builds after cleaning, purging and troubleshooting. Examination of the machine revealed that the support materials were not being dispensed in each pass of the head, and the machine was stopping the builds.
Assessment: Troubleshooting for possible head starvation issues and clogged nozzles in the print head.
Fix: After troubleshooting and a review of configuration files, it was determined that the support heads needed to be replaced. Further questioning of the customer noted that the machine was in a hot environment where the materials and machine were regularly exposed to temperatures over 85 degrees F on a daily basis. Recommended temperatures for operation of the machine and storage of the materials noted that the storage temps should be between 15 °C and 25 °C (60 and 77 degrees F) and the room where both the machine operated and materials were stored were usually above 85 degrees F during the nights with excursions to above 95 degrees F ( 30 – 35 degrees C) on a regular basis.
Conclusions – elevated temperatures contributed to early head replacement due to materials reacting to heightened temps over a long period of time while in storage and in the machine.
A couple of my friends asked about quick tips for finishing up FDM parts so they are smooth and polished looking. I was more than happy to help, but thought that perhaps our industrial users may want an overview of some hints.
First, Stratasys sells finishing systems for FDM parts that include vapor polishing (where acetone vapor smooths the surfaces) and has a referral network to vibratory tumblers and media blasters for other types of smoothing besides sanding. Power tool sanding equipment ranges from Dremel tools to palm hand sanders, but many users complain power tools take off material far too quickly for careful finishing, so most tend to tick to hand sanding.
The parts that adapt to hand finishing best are parts that have a long area of “plain” features. For example, a part that is shaped like a cup would be ideal for hand finishing since there are not small cracks and crevices to try and dig into with a small tool to smooth out. The sides can be smoothed out and if desired, the part can be finished by painting.
First off, remove any support material that remains from the build. If the part will be painted later, you want to print in a color that is as close to your final color as possible. For example, if you intend to have a blue part, print the part using blue filament and after finishing paint in blue. You will find that your part may need little paint in those cases. Starting with your clean part use coarse grit sandpaper to knock off any obvious edges and defects and gradually move down to the fine grit sandpaper. (Start with coarse then move to fine line so – 100, 240, 400, 600, 1500, and 2000 and so on using what you have on hand.) If you have a perfectly flat surface that you are wanting to sand, a sanding block out of balsa wood keeps uneven pressure from your fingers from causing a divot on the surface. Between changes of sand paper washing or blowing off the surface with shop air will allow you to check your progress.
Once you have finished sanding and are looking for the final touches, you can polish the part with a plastic buffing compound. Note that if you are using a wheel or Dremel pressing too hard may cause heat build-up on the part surface. If you intend to paint the part, the part should be washed to remove all traces of grit, dirt or oil.
When painting the parts, make sure that the paint selected is compatible with the type of plastic you are coating. And, thin coats are much easier to control for gloss and drips than attempting to do a thick coating and short cutting the process.
On PolyJet parts, because of the superior surface finishes, you usually do not sand for finishing. On occasion, sanding is used to prep the surfaces for paint, but usually you don’t need to smooth and polish the surfaces. Ensuring the part is free of oil and dirt by washing is a good insurance policy to help assure paint adherence. Some customers prefer to paint matte surfaces and build with this finish and some gloss, but most are not painting. If you have the new J750 machine for PolyJet parts – decoration and painting is not needed – you can get the CMYK colors in and throughout the build by using our latest machine. Logos and colors can be transferred from VRML files and 3Dpdf files into the build data and the 3D printed parts look and feel like the product pieces.
Want more information on the J750 click here.