The first layer of a 3D print is one of the most important. It sets the stage for the rest of the print. I relate it to the old adage questionably attributed to Abraham Lincoln, “If I had 5 minutes to cut down a tree, I would use two-and-a-half minutes to sharpen my axe.” I have been known to spend two hours or more calibrating that first layer of a printer to make sure that the results are repeatable and reliable for as many prints as possible.
If your Z height is not calibrated perfectly (or within a certain margin of error), there are two main problems that can occur:
Problem #1: First Layer Too High
If your first layer is too high, your print will not stick to the bed properly and will most likely pop off somewhere in the middle of printing, usually long enough in to the print time that you have stopped watching the printer but early enough to ensure a good amount of filament spaghetti or blob of filament on your hot end.
Problem #2: First Layer Too Low
If your first layer is too low, your hot end will drag through each previous layer. This not only creates an unsightly top layer but also will make your hot end prone to clogging very quickly. Additionally, your layers will be more smooshed, causing the filament to spread out to the sides of the nozzle and increasing the thickness of your designs, thus making fitted pieces very difficult to print.
BuildTak to the Rescue
I first saw BuildTak in a rather serendipitous way. Someone had just posted a new print of one of my designs on Thingiverse and I went on to check it out. On their build plate, below my printed design, was this strange black material where I expected to see blue tape or kapton tape. Fortunately for me, the label of the material was visible and I put my CSI “enhance” skills to work and was able to make out the words “BuildTak”. After some quick Googling, I found the material and started reading reviews. Everything I read was positive about the material so I decided to order some samples from Amazon to test on one of our Printrbot Metal Simples.
I had to cut a small strip off the sheet to make it fit on our bed and then I recalibrated the bed probe for the thickness of the sheet (it’s much thicker than blue tape or Kapton tape). We tested the new bed material during one of our field trips to the Tech Center and I was amazed how quickly we were able to pop the print off and start a new print without having to replace or repair blue tape. It was shaving a minute off of our print transition times (which is a big deal when you have 25 keychains to print in 90 minutes or less) and we were getting even more reliable prints than our printers with blue tape. Additionally, there were no bits of blue tape stuck to the bottom of the prints.
After the first two days of testing, I was convinced and I ordered enough BuildTak for all of our printers. You can get it from Amazon and I was getting 3 sheets for roughly $25. In theory, BuildTak will wear out and need replacing. I’ve heard somewhere over 100 prints is when it will need replacing. At this point, we are just about at 150 prints on the first printer I tested the BuildTak on and I don’t see a need to replace it. I’ll update this blog post when we do replace our first piece.
BuildTak does a great job of grabbing that first layer of filament and holding on to it. Even if your settings aren’t perfectly calibrated, chances are your print will still come off great. Plus, you get the added bonus of not having to re-tape every 10 prints or so. The material gives you more room for error on your first layer settings and you get better prints even if your settings aren’t dialed in to the micrometer.
In short, I’ve been really impressed with how much easier BuildTak makes it to get a good first layer. It gives you a much larger buffer for your “perfect” Z height and lasts longer than blue tape.
We replaced our first piece of worn out BuildTak after 1,277 prints.
I did some fun math to see how BuildTak compares to blue painters tape in terms of costs:
BuildTak roughly costs $9.61 per sheet. At 1,277 prints, that’s a price of $0.0075 per print.
Blue painters tape is roughly $14.65 for 60yds x 2″. I estimated that I can get 800 prints per roll of painters tape, that’s a price of $0.0183 per print.
Pretty small costs all around but I also think BuildTak saves time compared to blue tape.