CAD Work Continues in a Busy Summer

Hello Everyone,

Thanks for stopping by to check up on us. Well, the busy summer schedule associated with the "day job" combined with summer family activities has kept me out of the shop for almost 8 weeks! Fortunately, for the time being, there is always CAD work to do. It gives me something to do while commuting, sitting on call, sitting in a hotel room and any other long periods of time I spend sitting.

Of course, the biggest news of late is covered in the previous post; The 6th Prowler to fly. I will update again after Bud's follow-on flights. Congrats again, Bud!

IN THIS UPDATE:
1. A New Addition to the Prowler Shop
2. Bryan & Todd visit Ray and his Prowler
3. AirVenture 2010
4. CAD Work Progress

1. A New Addition to the Prowler Shop - The newest news is something that I've been working on for a good part of the summer. I came across a gent that had a 3 axis CNC Knee Mill for sale in his garage about 10 miles from the Prowler - West shop. It had sustained some damage and was sitting on a pallet and hadn't run in several years. To make a long story short, I took a gamble, put in a low-ball offer and bought the mill. Turns out that all the damage was just superficial and visual, but did not affect the functioning of the mill in any way. The only 1/2 day that I've had in the shop since mid June was hooking up the mill and testing it last Friday. Here it is:
Happily, the mill works fine and will be invaluable in making Prowler landing gear parts (or any 3D parts) in the future. We weren't really ready to spend the $,$$$ for this right now, but I was able to get it at such a ridiculously low cost that I couldn't afford NOT to do it now. Another sizable learning curve to conquer! Tally Ho.

2. Bryan & Todd visit Ray and his Prowler - In July Bryan and I both had some time off on the same day in the LAX area. Ray was available that day, so we drove up to see him. Bryan and Ray were able meet in person and it was cool to watch two guys that are very knowledgeable about Prowlers converse and compare their building experiences. Here's a pix from the visit:
Ray's airplane is moving right along. The day we visited Ray, he was just beginning the process of pulling many of the systems out of the cockpit to make room for riveting on the skins on the sides of the cockpit. He should have that done by now and be in the process of re-installing all of the systems. With that complete he will soon be tackling the engine and related systems. Here's a current pic of his panel:
It was a great day and we all enjoyed the visit. Thanks for hosting on short notice Ray.

3. AirVenture 2010 - One word universally sums up AirVenture this year - WET! It rained nearly 3 times the average monthly July rainfall for Wisconsin in the week just before AirVenture. There were large sections of KOSH and the EAA grounds that were not usable and were sectioned off so that planes, trains, automobiles and people wouldn't get stuck in the mud. It made for a fairly disorganized show this year, but the show did go on. It's truly amazing what EAA managed to come up with for alternate plans (on several fronts) to keep the show going, despite the weather. Here's a pic of an impromptu Prowler meeting with (L to R) Todd, Rick and Bryan:
The two highlights of the show for me this year were seeing two beautifully restored airplanes that have never been at any airshow before. This first one is a VERY RARE Royal Navy Spitfire (Carrier Version)!! Yep, with folding wings and a tailhook! There are only 4 known to exist like it in the world, and this is the ONLY ONE that is flying in the entire world! The restoration on this airplane was the best that I have personally ever seen. This is an absolutely gorgeous warbird:
The other airplane was "Kathleen" a newly restored F4U Corsair. My personal favorite. If I could have any plane I wanted - the Corsair would be it! This one is owned by a former TWA guy who bought it from someone out of a jungle in El Salvador in the early 70's. It was restored by Airpower Unlimited in Jermoe, ID. It's a beautiful aircraft:
All things considered, it was a great time. Then again, the worst day at AirVenture still beats any other day of the year - period!!!

4. CAD Work Progress - I think I can safely say that I have about 2/3 of the Prowler parts CAD'ed out. Each part is actually drawn 4 ways: First - a standard 3-view of the part; Second - a flat pattern drawing of the part; Third - a plasma tool path drawing; and Fourth - a 3D view of the part. In addition, I then take the individual 3D part drawings and put them together into sub-assembly drawings (where appropriate). Here is an example of all of the Radiator parts gathered together into a 3D drawing (with one side off):
The colors are there for contrast to distinguish one part from the next. To date, here is the status of CAD work for the Prowler Sub-Kits:
Completed - Vert Stab, Horz Stab, Elevator, Rudder, Center Wing Section Main Spar, Outboard Wing Main Spar, Torque Boxes, Center & Outboard Rear Spar, Center Wing Components, Outboard Wing Components, Radiators, Ailerons, Flaps;
Remaining - Main Landing Gear, Fuselage - Cockpit, Fuselage - Aft, Tailwheel Components, Engine Compartment Components.

At this point, I am hoping to finish the majority of the CAD work by the end of the year. Once that is complete, we will start using the CAD info to begin making parts for our airplane. From this point on, when we make a part for our airplane, we will be doing it using the same processes that we will use in production later.

That's it for this update. Thanks for stopping by.

Another Prowler Completes 1st Flight!!!!

Congratulations to Bud Tedesco on completing his 1st flight! Bud reports that he and Prolwer N12BT took to the skies on 30Jul2010. Bud says the plane flies great and is very light and responsive on the controls.

Here is a video of Bud starting his Prowler before the first flight.


This is the video of his first flight. Right after the initial lift off you will see the airplane appear to sink back toward the runway. According to Bud that was intentional as he was going to set the airplane back onto the runway because of a "funny" engine sound. But the Prowler moves so fast that he realized that he was out of runway, so he again powered up and pulled back on the stick to continue the first flight. That sink apparently caused a few gasps back with the ground crew. He didn't really mean to scare anyone, and there wasn't anything really wrong with the plane.


Here are the YouTube links for these videos. You may find these have a little better quality:

http://www.youtube.com/watch?v=ZB1Ce1esYVc
http://www.youtube.com/watch?v=yJJrCm1tLec


Bud's gripe list from the first flight includes:
1. Oil pressure - seemed to be be fine before flight @ 65psi, but he noticed it was around 15psi during the flight.
2. A heavy left wing - will most probably be fixed with some simple rigging changes to ailerons and flaps.
3. Engine running rich - Bud is going to dig into the books and see if he can adjust the mixture linkage and mechanical fuel injection system to get a better setup.

He also reported that the flight controls are very responsive and you don't have to actually "move" the flight control to get the desired outcome - just a simple "pressure" will do.

Once again, Congratulations Bud!!! This is a monumental accomplishment. You should be very satisfied. Great Job.

I'm also WAY overdue for a Prowler Blog update. I'm going to try to get to that ASAP. Until then I'll be working the day job and dreaming about our first flight. Thanks for stopping by.

We Had Pop In The Shop Again!

It's hard to believe it's been 3 months since my last update! The end of March signaled the annual spring trip where Grandma & Grandpa stop to see the grandkids on the trip home from snowbirding in the southwest. It's great, because Prowler gets the benefit of having a retired Iron Worker in the shop that has spent an entire winter in an RV without welders, grinders and cutting torches. We got a lot done - but I think he thought he was a job foreman again! Here's the list of topics in this update:
1. Sheet Metal Brake Update
2. Grinder Bench Fabrication
3. Plasma Torch Mods and Update
4. CAD work
5. Bryan's TW Strut
6. Forks for the Tractor
7. 30" Shear/Brake/Sliproll Fix
8. Next Update

The balance of the time since the last update has gone into working the day job and hasn't allowed a lot of time in the shop. On with the update:

1. Sheet Metal Brake Update - By far, the majority of the shop work in the past months has been working on the 8’ sheet metal brake. Here’s what it looked like after the restoration of what we initially got.
After completing this restoration of the existing parts, work began on the new parts that would be needed to build the missing top clamp. Using ideas from pictures of this same brake found on the internet and combining those with ideas from other existing designs (and a few of our own ideas), we came up with a plan. These are a few of the parts that were designed and machined to create an eccentric system that when rotated (by a handle) will create the lifting force to lift the top clamp (so the material can be slid into the brake).


Here are those same parts cleaned up and installed on the brake. When the round part facing outward is turned, the bolt is lifted upward (because it is off center). The other end of that bolt is welded to the upper clamp of the brake. Below you can see where the handle was welded onto this eccentric plate.



Here’s a pic of the long top clamp pieces being installed onto the end plates. There is a piece of a steel beam (upside down “T”) that you can see one side of in this picture. That beam was cut lengthwise by our Prowler Plasma system. That piece of upside down “T” iron is what the rest of the upper clamp assembly was built around.

Here are a few pix of the almost completed brake. It still needs to have some “tweaking” done and also needs painting. Notice the stiff-backs that were added to the upper clamp assembly and the counter-weights that were fabricated for the folding leaf (to assist in bending the material). These were all missing when we got the base unit.


2. Grinder Bench Fab – As mentioned in an earlier post, we got this carbide grinder setup for free (for getting the sheet metal brake out of the gent’s backyard). The internal motor had burned out, but someone had modified it and set it up to be used with an external motor. The cabinet that it was mounted in when we got it was trash, so we pulled out the good parts and installed them into a new bench. There will eventually be several other bench grinders and buffers installed onto this bench so that all of these tools will be organized into a single, movable work station.



3. Plasma Torch Mods and Update – Because we built a new torch height control system for our plasma setup, the distance that the torch head actually stands off from the gantry and carriage had increased by about 5 inches. You can see the amount of stand-off in this pic.

That caused a problem with trying to cut long pieces in between the structure of the plasma table. Even though there was 8’-4” of space between the frames of the table, the torch could not travel far enough to the left to use all of this space in between the structure of the table. So, we had to extend one of the rails that the gantry runs on. It really amounted to cutting about 6 inches of this rail system off of one end of the table and mounting on the other end. Then moving the X axis gear track to the left the same distance. In this pic you can see this new extension piece after it was cut off the right end of the table and added to the left side of the table (and the gear track moved).

The problem is now solved and we are able to cut in lengths up to 8’-2”. As mentioned above in this post, we used the plasma torch to make one of the parts for the sheet metal brake. We cut an “I” beam in half the long way to make a “T” shaped part. The torch worked great and the part came out nice and straight.

Overall, the plasma setup is working really well. It’s also becoming more useful as we learn more about how to use it. We’ve gone from using 60A tips to using 40A fine cut tips and they work very well. So far we’ve only cut steel, but we’re going to expand into cutting aluminum sometime soon. Recently while cutting some parts for a friend, the auto height control system was proven to be working just as it should. It tracked around a long part maintaining a perfect cut height even though the material was warped over ½” from end to end.

Also, as we get better at processing CAD drawings into machine code (G-code) we are finding it quicker to make parts with the plasma setup than any other way. Hopefully this tool will turn out to be a great way to cut a lot of our parts. Speaking of CAD work:

4. CAD Work - Hundreds of hours are going into creating these CAD drawings of each part of the aircraft. Turns out that the easiest parts to draw are the ones with straight sides, angles, circles etc. that can be re-drawn from scratch. The parts we're currently working on are very tedious and time consuming. This is because they have curves that cannot be replicated in BobCAD. So the parts must be traced, scanned (with a large format scanner @ Kinko's) and then the scan imported into BobCAD. However, when the drawing is vectorized in BobCAD it does not become a clean, usable drawing. It's takes hours of cleaning up and detailing the drawing to get the shapes correct. Here's a screenshot of a recent part (center wing section middle rib#4):

Here's a close-up 3D view:

5. Bryan's TW Strut – One of the fun things we got done during this update period was completing Byan's TW strut. It was a very good project for us to learn "the ropes" on getting real machine work done. Overall, the project turned out great. Here's a couple pix of Bryan's Completed TW Strut.


Here's a couple of pix where he has it partially installed for testing the fit, etc.


Bryan said he was going to give us an A+ with extra credit, but we only ended up with an A+ because we had one bore that was just a smidge too tight and he had to file it out just a bit to get the bolt to go in. The new bore dimension is now noted on the drawing! Glad you liked it Bryan.

6. Forks for the Tractor – This project was not even on the agenda, but a set of forklift forks (with the rack for the forks) came onto Craigslist at a good price. We’ve wanted to have forks for the tractor, so we purchased them. It only took a little modification (and extension) to make them fit onto the tractor using the same pin points that are used to attach the bucket.



It works great! It will be very nice having the ability to lift shipments of 2024-T3 off of the delivery truck (someday).

7. 30" Shear/Brake/Sliproll Fix – In a previous post we showed this combination tool that we got at a great price. We’ll, the broken arm has been repaired and the unit now works fine. It still has to get mounted to a movable table or bench – but it’s now ready to work.


8. Next Update: In the next update we'll try to have a status update for each of the current builders. Bud should be close to his test flight. Chuck should be flying off his 40 hours. Ray has been testing hydraulics and electronics and is headed towards mounting his engine.

This update comes to you in the midst of the best landscaping time of the year in northern CA. Since we haven't had a green lawn in 5 years, the pressure is on (me) to get the landscaping and irrigation done @ the Prowler (West) homestead - before the ground dries out and gets so hard you can't drive a nail into it. So, there won't be a lot of shop work getting done for a while. However, the CAD work is portable and the day job provides time sitting in a hotel to work on that.

That's all for this update. Thanks for stopping by to keep an eye on us.

2010 Is Off To A Great Start

Welcome Back. Happy New Year, and thanks for stopping back to check in on us at Prowler Aviation. We are off to a really good start in 2010. Here are the bullets for this update:
1. CNC Jigs
2. Tailwheel Strut Fabrication
3. Airplane CAD Work
4. A Free 8 Foot Sheetmetal Brake
5. More Tools
6. Cabi Saves Kit #9 from the recycling SCRAP HEAP!!!
7. Bud's Airplane (Kit #16) Attempted First Engine Start
8. Chuck's Airplane (Kit #12) FLIES AGAIN
9. Ray's Airplane (Kit #10)

Here's the Latest:

1. CNC Jigs - We recently had to fabricate jigs for 2 parts that we have in the CNC process. To make production as simple, pratical, and repeatable as possible you have to find a way to hold the stock rigidly while the machine does it's thing. You also have to find a way to hold the stock without machine hitting something that it's not supposed to. So far we made jigs for the steel wing plates and the TW strut.

2. Tailwheel Strut Fabrication - is nearly complete. Bryan has asked to have a TW strut fabricated. His kit never had one and he's going to begin the fuselage soon and wanted to start lining up all the parts. So, as we've shown in previous posts, we did the CAD work for the TW strut and got the machining done. One of the steps in the process was CNC shown above (jigs). The bushing holes still need to be reamed and the bushing pressed into them - but the processes are now in place to make these parts in the future.

3. Airplane CAD Work - We've been working diligently on the CAD work for the airplane. We've finished the drawings for the Vert Stab, Horz Stab, Rudder, Elevator, Main Wing Spar, Outboard Wing Spars, Rear Spars, Torque Boxes. The measurements have been done for all of the Center Wing Framing Components and the Outboard Wing Framing Components. When the drawings are completed for these last two sections, we will have completed a CAD drawing for roughly 1/2 the airframe components. The next step in process will be to go back and assemble the individual components into sub-assemblies where appropriate.

4. A Free 8 Foot Sheetmetal Brake (Sort-of) - We got a line on an 8 foot sheetmetal brake that a gent in SoCal was giving away to a good home. It's not a complete sheetmetal brake, however, and needs a lot of TLC. The base of the brake and the bending fence are are what we've gotten, but it's missing the top parts that clamp the material while bending. With a bit of elbow grease and fabrication of some parts, it will become a servicable unit - for a lot less than purchasing one. So far we've taken possesion of the brake, transported it to the shop, taken it completely apart, stripped and sand-blasted all of the parts and then painted everything. The next time in the shop we'll get pieces all re-assembled and get a start of fabricating parts to build the top, clamping part of the brake. Here are pics of what it looked like on arrival:
Started the tear apart, cleaning, sandblasting and fixing:
Sandblasting (effective but VERY tedious and messy!): Painted Pieces ready to go back together:

5. More Tools - We ended up picking up a few more tools from the gent that gave us the sheet metal brake. One of the tools is a Tooling Cutter/Grinder. It's a machine to make precise angles to make and/or sharpen toolings for mills, lathes, etc. It was a good deal and it will be nice to have the capability. Here's a pic: Clean up and restoration of this tool is on the back burner for now. At least until we need to sharpen some tooling.

The other item we got was a 30" combination shear, press brake and sliproll. Here it is before cleaning: It was a great deal because it has one broken arm. Here it is after cleaning:Here's the CAD drawing for the Prowler Plasma to cut out a new arm. We should have it fixed up in no time. More later. One of the great things of building this company slowly is that we have the time to find these "diamonds in the rough" and polish them up. It saves a lot of $$$ - but it does take time. Since we are not in any huge hurry, we can use this process to position the company for financial soundness.

6. Cabi Saves Kit #9 from the recycling SCRAP HEAP!!! - Late last year Cabi completed tracking down the old Prowler Aviation's Kit#9. The kit had changed hands a few times after it had been purchased from George. Somehow Cabi tracked it to a local college that it had been donated to. It languished there for years and ended up stored in an old CONEX box container. The college was very close to selling it for the scrap aluminum value. Cabi got the kit for value of the scrap metal. What a deal! Nice work John. Here are some pix:












7. Bud's Airplane (Kit #16) Attempted First Engine Start - Got an email from Bud recently and he reported that he's attempted the first run-ups of his airplane. The engine didn't fire and after some investigation he found out that many of the silver solder joints on the fuel injection manifold had somehow become (essentially) closed off. So, he is in the process of making this right and we expect to hear good news from him soon. Here's a file pic of Bud's airplane from a visit last fall.

8. Chuck's Airplane (Kit #12) FLIES AGAIN - Last year Chuck was having engine troubles. The engine wasn't running real well, there were engine oil and water cooling issues - among other things. Chuck found a sharp fellow to help him tear the engine apart and find out what was going on. What they found was that one of the distributors was damaged and the engine appeared to be running in a severly "advanced" ignition timing condtion. This had badly damaged one pistion and somewhat damaged others. After many months of rebuilding, the airplane flew again in Jan. Chuck reports that the airplane flew well, the gear cycled well but the engine was not producing "linear" power. The engine ran great and "pulled like hell" at takeoff power, but as soon and the power was reduced, the engine power got "mushy" and difficult to control. He and his technician decided that there were some tuning issues between the mechanical fuel injection system, the supercharger system and the engine. They decided to remove the supercharger system from the airplane. After that, the engine ran great, the power was very controllable, and the airplane performed very, very well. Here's a pic of Chuck and his plane from a builder visit in 2008. In a later flight, the test pilot reported that the only remaining "gripe" was that at about 175 mph he ran out of elevator trim. So they will be focusing on getting the Horz Stab incidence set correctly in the near future. After that, Chuck says he will pay his pilot to fly off the 40 hours required to get the Experimental Certificate and then he will be putting the airplane up for sale. Stand by for more.

9. Ray's Airplane (Kit #10) - Is almost ready to get an engine - Ray reports being very close to completing the avionics installations in his airplane. He wants to get most of the wiring completed and get the avionics mostly complete before moving on to the engine and firewall forward. His goal is to get a good start on the engine mount and the the engine installed this year. Here is the most current pic we have of his instrument panel.
That's all for this update. More when additional info and time will allow. Thanks for stopping by.