What Holds the Joint Strike Fighter Together?

What holds the Military’s new fighter together? The answer to that is adhesive bonded fasteners by Enfasco. Yeah, thats right we’re talking GLUE here. I’m sure those glue specialists would prefer I use the term “Adhesive!!” I bet you’re wondering what possibly could one of these things look like? Here…

Stainless Steel Fastener

I came across these while looking for an innovative solution to mount a product we’re working on to the hull of a boat. After talking with the application engineer over at Enfasco, it is actually pretty common to use these in the marine world. Apparently NASA also used them in the space station.

Base of fastener

What makes these so incredible isn’t that they are an adhesive fastener. It is their patented fixture which holds the fastener to the bonding surface and the fact that it is disposable. To apply one of these you first squirt some adhesive onto the base. Next, you will remove the paper backing on the double-sided tape of the fixture. Then you place the fixture onto the surface to bond to and push the upper part of it firmly. The fixture uses live hinges that cams the entire fastener to the bonding surface and applies force until the adhesive is cured.

On the left is the fixture before “set” and on right is fixture as its received. If you look closely you can see the live hinges which work nearly identical to the live hinges on your shampoo bottle lids (or catchup).

Live hinges of fixture at rest before being applied to surfaceLive hinges cammed down to hold position

If you ask nicely Enfasco will even sell you a very convenient bonding kit that comes with all the necessary supplies and is one time use. This is great for the reason that it leaves no clean-up to worry about. This kit comes with the following:

  1. Acrylic adhesive (other types available)
  2. A solvent wipe to clean both bonding surfaces
  3. Scuff pad to rough up the bonding surface before adhesive application
  4. Popsicle stick for stirring and applying the adhesive
  5. Mixing pallet to stir and apply from

Adhesive Kit

Here are the instructions to install these:

Instructions

If you are interested in purchasing any of these you can get a hold of Enfasco over at their webpage. They have all different shapes, types, sizes, and materials.

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5 Neat Ideas for Your Product with a Printed Circuit Board

  1. If you are using a 7-segment display or an LCD that is circuit board mounted this idea may be perfect for you. Instead of using a harness to connect the display to the main board, solder the display board directly to the main board.  Design the board so the copper conacts run all the way to the edge of both boards.  Next, solder the two boards together at a 90 degree angle. Make sure to place some mechanical pads with vias for support and to prevent the pads from pulling up.

    Render of attaching two PCBs together at 90 degrees

  2. Leave off headers for programming and debugging (serial ports and usb ports) and instead use edge card connectors or spring pins and a custom PCB to mount them to. The expense of the custom pcb is much less than the reoccurring cost of the extra headers and connectors that are not used by the customer.
  3. Card Edge Connector

  4. Reconsider design reuse when it comes to schematic design and board layout. With more and more devices going wireless there is a need for a transmitter and receiver. Typically these are actually both transceivers. In many cases, the base station has a similar layout to the transmitter. Consider building a module that has all of your radio (or similar) components on it and soldering it down to your main board. This not only saves you money when it comes time to have the boards built, it also saves you from having to design two separate boards. Additionally, with the wireless revolution, if you are building small quantities consider using a COTS radio module as they are much cheaper than spinning your own (in low qty’s). Furthermore, they work without much work (usually)!
  5. Bluetooth Module

  6. If you have the space, a well designed 2-layer circuit board can perform as well as a 4-layer. The most important thing to consider is cost vs time. The 4-layer board will cost nearly twice as much as the 2-layer which is significant at any purchase quantity. However, the 2-layer board may require a few more prototypes to get right, especially if its a transceiver.

    Application Schematic

  7. If you are designing the schematic or you are hiring a consultant to do it consider leveraging work that someone else has already completed. Many manufacturers publish application notes that have a reference schematic which has been tested and documented. Typically these designs work very well and require zero to few minor modifications. This will save you a lot of time and money in the long run. Additionally, these same companies have application engineers (usually the guys who designed the reference schematics) who can answer questions.

Whether you are working on a board design or conceptualizing a new product, give us a call. If nothing else, we might be able to point you in the right direction and save you some time.

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Taking the Delonghi Magnifica Apart

The story starts off with me noticing that recently while pulling shots of espresso, the espresso machine has been getting slower at extracting the shots. I adjusted the grinder about 30% and that seem to have fixed the problem. Because the grinder is a conical burr grinder it shouldn’t get clogged. However, I wanted to take it apart to clean it and see how it all was put together. I didn’t get a chance to take the grinder apart because it had more parts than I wanted to deal with on a Sunday morning. I did however snaps some good pictures which you can see below.

Inside front of machine with tray and carrier installed

This is the machine after the front door is opened. You can clearly see the carrier and its release tabs (red).

Inside front of machine with tray and carrier removed

I have removed the carrier and the drip tray with the used espresso puck container and set it aside. As you can see, it gets pretty messy in there however it is easy to clean out.

Rear of machine with pump and carrier motor

Besides awfully messy wiring (came like this, i promise), there are two things to note in this picture. The first is in the middle of the machine you’ll notice the 15 bar pump which has a label on it. This pump is the main pump used for pulling shots. Then a bit lower and to the left is a large motor. This motor is what drives the carrier up and down. It is large because it is used to drive the carrier into the tamper in compress the grinds. It appears as though there is some mechanical advantage happening here but I didn’t determine how much.

Inside right side of machine with heater and water filter

Here we have the right side of the machine. On the top tucked underneath you’ll notice the very shiny aluminum block. This is the heater and serves two purposes. The water is heated here and the radiated heat is used to heat the shot glasses which are placed on top of the stainless steel plate. Also, on the bottom of the machine there is a small water filter that connects into the tubing from the water reservoir (not present in this picture). It’s nice to know they added such a simple yet potentially product-saving item. It’s incredible how many products out there cut corners in these areas. Sometimes it’s only one little item that was overlooked or vetoed by the accountant that kept it from receiving “excellent” reviews. I’m happy to state that this Delonghi Magnifica is not one of them and I have been thoroughly satisfied with it. On to more pictures…

Combined brew head and tamper

This is the brew head where the magic happens. When the carrier comes up to this location it presses (tamps) the grinds and brews the coffee all at once (genius). The red o-ring is there because this brewing head actually slides down into the carrier. This provides the seal to hold in the very high pressures used when pulling espresso shots. See the next image for detail on this part of the carrier.

Combined brew head and tamper

This picture is looking down into the top of the carrier. This is where the brewing head resides when pulling (pumping) a shot of espresso. At the bottom is the metal grate which acts as the filter. It keeps the grinds captive while allowing the espresso through.

puck flapper

This picture shows how the puck slapper scrapes the used espresso puck off into the bin. When you empty the pins the pucks are surprisingly very well intact and easy to dispose of. In the summer, we use them in the garden as fertilizer.

Main circuit board

Lastly, we have the circuit board. Upon close inspection they’re using a microchip microcontroller and several mosfets for heater and motor control. With just a cursory glance the circuit board looks quite nice and well designed. My only gripe is the messy wiring seen on the rear of the machine. It’s so easy to throw in a few ties and makes all the difference during servicing and troubleshooting.

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Easy No-kink Hose

We’ve all been worn out by cheap kinky hoses. So you’re leaving for work and notice that your flowers are dying and need to throw some water on them real quick. You go to drag the hose out to where you need it and then run back to the house to turn it on. After cranking on the faucet you run back to the end of the hose to water the flowers. Pull the trigger on your nozzle and….. nothing.

There are many different ways to skin a cat as there are to make a kink resistant hose. Here is a neat one I came across while disassembling the coffee maker for a one-on-one cleaning session. I didn’t get to what I wanted to clean but I sure got some cool pictures.

Spring inside small tubing

Notice a small spring is used within the hose. It starts prior to the arc in the hose and ends shortly after. This provides internal support that keeps the hose from kinking. In this case they’re simply using it because they have a tight radius to bend around. In some cases this method can also be used to prevent hose collapse under high vacuum. Typically you would use a hose designed to withstand the vacuum, however sometimes these problems don’t creep up until the products hit the production line.

If you can appreciate things like this then we may be the right design house for you. On the other hand, If you’re really on top of your game you’ll tell us that we should appreciate a better design instead of a quick fix like this! :) Either way, we’d love to talk. Give us a call or fill out our easy inquiry form.

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Inside the Delonghi Magnifica Espresso Machine

So here we have a Delonghi Magnifica super automatic espresso machine. This is one beautiful piece of machinery. I’m not saying this because of its aesthetic characteristics but because of how well it performs. After using a manual machine with a blade-type grinder to make espresso every morning, upgrading to a super automatic is like a dream come true!

Many espresso/coffee purists would say that a super automatic machine is akin to taking a Geo Metro and putting tires from a Ferrari on it hoping for Ferrari-like performance. I disagree. When you consider the quality of the result combined with the time/hassle savings, it becomes a no-brainer.

Down to business… Check out this first video showing the basic brewing of a shot of espresso. It shows what a “good” shot should look like with the crema on top. I muted the sound as its rather uninteresting.

Next we have the video with the door open. Those clever guys over at Delonghi spared no expense when it comes to fault detection (door switch, water level, used espresso puck level, mineral buildup counter, etc). As a result, a paring knife was used to overide the door switch. I will go into more detail in the up coming days as to what does what.

Here is what’s happening in this video:

  • The carriage (black plastic with red tabs) is moving from its brewing location down to its home position. We also call this the dump position. This is the position where it dumps off any pucks of ground espresso. If you watch the video closely, you can see the flapper moving away and slapping the buck into the bin (there is no puck yet but if there was, that is what it’d do).
  • Now the carraige moves up to the grind location. The grinder will grind beans (after user selects serving size button) found in the hopper on the top of the machine. The grinds will fall out of the grinder and into the top of the carriage.
  • The carriage now moves up and to the right. When it does this you’ll notice after it stops, it moves slightly up again. It is actually compressing (tamping) the grinds into the carriage. Typically, on a manual machine this is done by hand with a tamper. Because this machine has a combined brewing head and tamper, it is able to stay at location after compressing the grinds to brew.The machine will immediately start the pump to begin the brew cycle. It does something called pre-brewing where by it wets the grinds down and waits a few seconds for them to saturate. This allows for a better shot of espresso. After the grinds are wetted it will execute the remainder of the extraction. In this video you’ll notice that the shot has an awefull lot of crema on top. I found it interesting myself how much more there was when the door was open and the espresso was falling straight into the glass instead of through the machine’s shoot. I believe I may have my grinder set too fine and will have to check into it.

Combined Brew Head and Tamper

  • After the extraction is complete, the carriage returns to the lower position and simulataneously ejects the puck of spent espresso grinds.
  • The carriage returns up to the grinder to wait for you to request another excellent shot (or 2) of espresso.
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