“EMG-6 Shop Notes” is a day-to-day accounting of what’s going on in the shop with the EMG-6 Electric Motor Glider.Hello
January 29, 2016 Upgrade to the EMG-6 Blog
We have just recently added the capability to be able to automatically convert email responses into blog posts. This will greatly enhance the transmission of information as we regularly get the exact same questions asked over and over again. In addition we have added a tab called Q&A at the top of the blog for easy access to all of the future posts related to questions asked by the general public and customers. Link to Q&A Page
January 27, 2016 Aircraft Spruce Now Stocking the EMG-6 Streamlined Struts
Aircraft spruce is now stocking the streamlined struts used On the EMG-6. Although aircraft spruce will be our only outside supplier for the streamlined strut material, You can still purchase the streamlined strut directly from us if you are an aircraft builder and have a serial number. And of course EMG-6 builders will receive a substantial discount Over the Aircraft Spruce price.
January 25, 2016 Parts Manufacturing Continues
We’re just finished with a redesign of the rear spar attach fitting.
These parts are replacements for the Quicksilver parts that are no longer available.
We’ve taken the time to much improved the design and simplify the attachment process.
Because this aircraft incorporates a wing fold system the fittings on both the forward and rear spar have to be strong enough to withstand the constant removal and re-installation.
The rear spar attachment adapter tube is almost identical to the original to with some slight modifications.
It now requires much less machining as we have redesigned the attachment fitting on the fuselage to allow all of the holes in the attachment tube to be drilled perpendicular to the tube center axes.
we were able to accomplish this by redesigning the attachment fitting that bolts to the fuselage boom and aligning the attachment holes at a very specific angle which allows for the trailing edge sweep at 3° in conjunction with the 3° dihedral in the wing.
the part is only 3″ x 4″ and so is fairly simple to machine with our 3-D machining technology that we possess.
The weight of the part is about .3 pounds
And like with many of the CNC machined parts, we subsidize the cost of machining and pass on the savings to our aircraft builders to reduce the overall cost of building the aircraft.
January 23, 2016 Wild Weather in Corning California
This picture was taken by Matt Nolan after a major thunderstorm went through the area and dropped nearly 2 inches of hail in some parts of Corning.
The path of the storm moved to the area quickly, Some areas got more Hail than others, But there was multiple reports of hail damage to vehicles.
In the background you can see the storm moving south.
The water piled up quickly behind the hail and flooded all of our hangers.
From the runway looking at the offices at the Corning airport.
I’ve been in the area over 25 years and am never seen the runway covered like this. After all it is California.
The roadway in front of the hangers going to town. The road was flooded for several hours.
January 23, 2016 Design and Manufacturing of New Wings Fold Fittings (Part 2)
The second part of the wing fold redesign was the incorporation of internal straps riveted to the wing spar using 3/16 inch stainless steel pop rivets.
The primary purpose of these fittings is to align the spar and transfer the loads from the wing spar into the wing fold fitting.
The wing fold strap drawings have been added to the builders database.
These parts are manufactured from 1 inch x .25 inch 6061 T6 aluminum.
The wing fold strap is radiused on one side to be of the provide for a close tolerance fit inside of the wing spar reinforcement tube.
The blanks are cut off in the metal cutting bandsaw.
In this case here we had some stock material of 2024 T4 aluminum that were using for this first run.
They are cut into 6 inch blanks.
The setup on these is rather difficult because there’s not much to hold onto.
They are fit into the milling vise and extended out onto a platform attached to the bed of the milling machine.
During the most difficult segment of the Milling where we have to cut the profile through the entire thickness of the material in one pass it requires that we Cleco the fitting to the base and use a quick clamp to hold it down to prevent chatter during the cutting process.
Once we pass the heavy machining on the end of the fitting, the clamp and Cleco can be removed and the machine can finish up on its own without any additional support.
The wing fold attachment fitting and the wing spar straps shown in context on the table.
January 21, 2016 Design and Manufacturing of New Wing Fold Fittings
We have finished redesigning the wing fold attachment fittings.
These fittings will provide for a better wing fold mechanism.
The original wing fold Incorporated a U channel. The U channel was functional but the new design allows for a lower profile getting rid of the protrusion of the U channel.
The design is slightly stronger than the original you channel and is also slightly lighter.
We have updated the drawings on the builders database
The fittings are manufactured from 6061 T6 aluminum. Or optional 2024 T-3 aluminum.
The manufacturing process involves five machining steps using the CNC lathe, milling machine, and drill press.
We start the manufacturing process with 3 1/2 inch long to inch diameter blank rods of 6061 T6 aluminum.
Over half of this material will be cut away during the machining process.
The CNC lathe cuts the blanks down to a shape resembling the setting in this picture.
A holding fixture has been cut into the jaws of the machining device to hold the fitting during the next machining process
A cutaway of the base was manufactured to examine the fit of the 5/16 inch diameter AN bolt.
The base of the internal portion of the fitting needs to have the maximum radius without interfering with the bolt head.
In addition to having clearance at the radius the internal bore of the fitting has to have clearance enough to fit a standard deep socket for the installation process.
A 1/4 drive socket and ratchet shown on a dummy part.
The first profile undergoes a rough cut as shown here and then he finish cut for the final product.
Once the machining has been completed the component has to be fitted into a machine fixture in the jaws of the milling vise and the wing attachment hole precisely drilled through the fitting.
The first run of wing attach fitting shown here in their completed state.
Will next have to package and label them and then they will be ready for shipment.
January 19, 2016 Parts Sourcing
We are continuing to manufacture and find solutions to the parts that were previously been made by Quicksilver manufacturing. We continue making progress in narrowing down the outsourced parts. We have recently been sourcing aluminum extrusions and have come up short so far. One of the more hilarious quotes that we got was for a replacement extrusion. Minimum order was for a single 12 foot piece. Which isn’t really that much material. We would probably be able to make enough rear spar attach fittings for 50 airplanes but with machining costs it would make the cost of A set of rear spar fittings over $100 apiece.
We originally had quicksilver manufacturing between 25 and 30% of the parts on the EMG-6 and we have now narrowed that down to about 5% of those parts that we still have not yet been able to manufacture in-house. However we continue to narrow the gap on a daily basis and we should have all of the manufacturing capabilities in-house within the next couple of weeks to months.
January 14, 2016 New “How It’s Made” Video (Manufacturing The Wing Strut End Fittings)
January 13, 2016 More Parts Organization
We continue to organize the manufacturing and inventory process.
We are now making specialized fixtures to accommodate many of the odd shaped components which allows us to organize segments of the construction into areas construction.
On the shelf we have the vertical stabilizer components as well as the low drag router parts.
In this fixture we are storing the upper and lower keel sub assemblies.
All of the components are now organized into bins and a new system for inventory and inspection is in place.
Placards for each of these sub assembly areas now make it easier to locate visually.
January 12, 2016
We have been finishing up on the manufacturing of the new batch of wing attach fittings.
After the parts come out of the CNC lathe they are placed on the milling machine for the threading operation.
Once all of the components have been threaded the milling machine is reconfigured for cross drilling the attached hole.
After the first cross hole has been drilled by the milling machine the fittings are moved to the V block to align and drill the adjacent side hole through the fitting
Of the block is a little bit more efficient way to drill the second hole in the fitting.
And once the V block is set up and the milling machine has drilled the first hole correctly it’s extremely accurate method for drilling the adjacent hole.
As the next batch of fittings are completed they will be Inspected before being moved over to packaging and labeling and then put into inventory.
January 11, 2016 Parts Production Continues
The parts that we have been working on today are the Wing strut end fittings.
These fittings will be inserted into the streamlined struts and attached with a 1/4 inch bolt.
Each aircraft will require four of these fitting assemblies to attach the wing struts to the wing assembly at both the forward and aft spar locations.
We are mass-producing these components in the CNC lathe.
They are manufactured from 1 inch solid round stock 6061 T6 aluminum
The components are manufactured with the bottom of the fitting sticking out of the hydraulic chuck.
This allows us to counter bore the internal part of the component.
There are total of seven machining steps in the production of this component.
The aft end of the fitting counter board to reduce weight.
And the opposite end of the fitting shown here with the threads already in place.
The threads are machined into the Fitting after it comes out of the CNC lathe.
We are using a role forming die to produce the threads.
This allows us to control the thread fit to a very high degree.
As with most of these components the setup process is a substantial portion of the work and so we will produce a significant number of fittings in mass production before we transition the machines to a different component.
Each aircraft requires four of these fittings at the end of each wing strut where they attached to the wings.
January 10, 2016 Update to Landing Gear Drawings
We have done some updates to the landing gear drawing files and posted them to the builders database
Keep in mind that these drawings are not updated on this blog
Refer to the builders database for most current revisions of all drawings.
January 10, 2016 Back in the shop
Many of you may have noticed that we have not been posting on a regular basis like we have in the past. That is because we have been on vacation for the last 20 days. Something I’m required to do approximately every 14 months in order to keep my wife Carol happy and in support of the EMG-6 project. The good news, our next vacation is not scheduled until February 2017. We’ve spent nearly the entire day working on customer support and answering emails after having been gone for so long. We were able to come into the shop this morning and turn the CNC machines on and start jamming aluminum into them and have been producing parts all day long.
January 3, 2016 On Vacation Shipbuilding Competition