57-10-51 Inboard Diagonal Strut Fitting Construction
In this posting here were just going to go through the process of manufacturing 57-10-51 inboard diagonal strut fitting.
This is just kind of an inside look into what takes place during the manufacturing process of some of the components on the aircraft.
The drawings on the builder database are PDF files that are used both by the builders or the assemblers of the aircraft as well as during the part manufacturing process.
The PDF file gives and in context orientation of the part for the overview of where the part is used As well as a detailed three view drawing for manufacturing purposes.
Once again we remind you every time we post something on one of these postings that the drawings are only updated on the builder database and not on these postings.
Once we have designed a part in solid Works and produced the drawing files we will create a PDF file that goes to the builders database and to the manufacturing database.
Working directly from solid Works into a add-on program called solid cam we will generate the toolpaths G code for The CNC lathe.
We will run several simulations to develop the most logical process for manufacturing the part
In these three pictures here we can see three Screenshots of the simulation in progress
On the left side of each of the screenshot you can see the eight different machining processes that take place in the manufacturing of this component.
Once we are satisfied with the simulations and solid Works we will then export the G code with a few more modifications over to the CNC Lathe.
We transfer of the G code file from the office computer onto a USB drive.
Plug the USB drive into a laptop that is temporarily set up by the CNC lathe.
Then using an USB to serial cable Connector transfer the information into the Mitsubishi controller.
Once in the lathe we will have to double check the tools that are needed for this process to make sure that they have been indexed properly.
The G code includes a positioning of the cutoff tool which is the first tool to be used To be used as a guide for inserting the aluminum stock material into the chuck at the proper depth.
The chuck is a hydraulic shock which is manually operated by foot pedal on the floor. We simply press the panel and the Chuck opens up, we slide the material to the index position. And pushed for pedal one more time and the hydraulic chuck holds material in place at 300 psi.
The first step in the turning process is to use the cutoff tool to face the part to be exact dimension.
Normally during this process there will be high-pressure coolant spraying on the part which would cause us not to be able to see what’s going on so we’ve turned off the coolant for these series of pictures
After we’re finished with the parting tool the Turret backs up and automatically changes the tool to the next tool to be used.
The next machine process is to use a center drill to start a pilot hole for the drilling process that will come next.
Next we will step up the drill size and boar down into the backside of the part internally.
This is a step drilling process Where we drill down approximately .1″ at a time then retract the drill bit fully which will allow the coolant to spray into the hole removing any remaining material before the next plunge into the stock with the drill bit.
This is called Peck drilling.
After only a few parts you can start to see the chips pile up in the bottom of the chip conveyor.
We’re not currently running the chip conveyor because were dumping the barrels of chips that fill up fairly quickly.
In this picture here we can see the chip conveyor has started and it’s moving the pile of chips on up the auger leaving all of the coolant behind and dumping the chips into a barrel.
Once we have bored the center of the part we can now use a 1 inch in the mill with radiused tips to bore the backside of the fitting.
This is also done in a peck drilling pattern this time cutting about .020″ at a time.
This requires a lot of coolant to cut this aggressively.
The next step is to use a 3/16 inch drill bit to drill the through hole.
This is the hole that the eye bolt will be attached through that provides the connection of the drag strut from the forwards far to the inboard section of the rear spar.
The next step is to The outer profile and simultaneously deburr the edges as this tool-path takes place.
The party is nearly finished and at this point where using the parting tool to cut the front face and separate the component from the aluminum stock material.
This path will cut almost through the stock material and then retract
Slow spindle speed to about 400 RPM
We then engage the parts catcher which fits just directly under the part.
We turn the cooling off.
Then the parting tool will cut through the rest of the part separating it from the stock material.
The fitting will then fall into the parts catcher.
The turret with the cutoff tool will then back up to the indexing position for the next part.
The spindle will stop.
The coolant will stop.
And the machine waits for us to once again re-position the stock material and push the start button.
After opening the chuck with the foot pedal we reposition stock material to the index point.
Remove our part from the parts catcher.
And start the process over again.
If we forget to remove the part from the parts catcher it will automatically retract and throw the part into the door for us to retrieve at a later time.
Parts will be set aside for the next machining process.
A look at the internal through whole board from the backside of part.
Parts will be dimensionally checked with a micrometer and visually inspected for flaws.
Total machining time for this portion of this component is about 15 minutes.
In fact as I’m writing this blog post the machine is running in the background and it has a very distinctive sound when the parts catcher engages to catch the part.
That gives me about two minutes to the end of the cycle and lets me know it’s time to go out and re-position the material once again.