This basic electromechanical timer was installed in a low voltage landscape lighting transformer. It lasted a couple months short of 10 years. I opened it up to see and show how it was designed and why it failed. The clock motor was still working. The contacts got eroded enough over the years that they were no longer closing.
A good example of simple and low cost electromechanical product design.
Engineer LLC will be investing in it’s first 3d Printer shortly, so we have been shopping the web for the best candidate(s). There are an number of options for the low cost (relatively) reprap based designs available. Ranging from scratch build with used parts to ready to print fully assembled units. Here’s a sampling of what I have found on the ‘net so far.
PrintrBot is an interesting newer product line of supplies, parts and kits. With the commendable goals of bringing the cost of entry even lower and making kit assembly simpler for beginners. This venture was launched via what appears to be the most successful Kickstarter technology campaign to date…
There are quite a few vendors popping up with offerings in the mid range with kits and some with fully assembled products such as PrintrBot listed above.
And then there’s the Granddaddy of all commercially available derivatives of the open source “reprap machine” with a Geriatric 3 years in existence… “Makerbot Industries”
For our first unit, we will likely be going with the Makerbot Replicator MK8 with the dual extruder option. This one comes fully assembled and features the all important dual extruder to allow for deposition of water soluble support material. When support material deposition is available, the printer is no longer limited to making only objects that are self supporting during build. This makes the unit more competitive with much more expensive “Mainstream” FDM printers.
It seems that the 3D printing bug may be spreading to Engineer LLC. There is a growing wave of enthusiasm for low cost (relatively) 3D printers, particularly in the Fused Deposition Modeling (FDM) category. FDM is a process that uses a plastic Filament fed through a heated extruder head to print a model from a 3D CAD rendering. It’s really amazing how the capability of these printers has improved while the cost of entry has also come way down. The new developments have been spurred in large part by the open source project “reprap”. Learn more about how it got started here.