More Production Capability Progess

Thanks for stopping in to check on our progress. Well, this is a BIG update - but the BIG boss was in town lately, and we got a lot done. Todd's parents recently made their annual spring visit to see the grand kids and Prowler also enjoyed some big gains from "Grandpa's" visit. As a retired Ironworker, Dad helped get several tools running, tuned up, and generally "shape the place up a little."

In this update:
1. Hydraulic Press
2. Bridgeport Mill
3. CNC Plasma Table
4. Builder Reports

Before we get started, just a few thoughts on where Prowler Aviation is today and where we hope to go in the future. In this update we will cover several facets of building our capability to manufacture parts for constructing our first Prowler. Our plan is to develop and use these processes to make most of the parts for our first company aircraft. By going through the aircraft one subkit at a time, we will eventually have the capability to produce most of the airframe.
Once that is complete, we will have the knowledge necessary to make the aircraft in (at least) one manner. From there we will be able to consider larger scale production and how we want to accomplish that. There will be many options and we will consider as many as possible to come up with a practical, economical, scalable and reliable way to produce airframes.

We plan to put one of George's engine designs onto our aircraft, but we currently do not plan to offer the engine for sale with the kit. We've decided to limit our scope (at least initially) to producing the airframe and save the firewall forward for later. We will also have (for the first time ever) complete, accurate and thorough documentation of the aircraft. This documentation will include a shop manual (how to build each subkit), the builder's manual system (how to assemble the subkits into an aircraft), a complete parts list spreadsheet, a virtual computer model of the Prowler, and a business plan.

That's the long term plan. If you've been keeping tabs on us in this blog, you'll see that we've made significant progress on several of these areas. Most of this update will discuss progress on the manufacturing of parts. Last summer we completed the "big sort" and did much of the parts list work. Modeling of the airplane's parts will happen as we make the parts for our airplane. The CNC plasma system is almost ready - as you'll see later in the update. The builders manual system will also be accomplished as we build the airplane, subkit by subkit. Two of the subkits shop manual parts have been completed and the rest will be done as the plane progresses. The business plan will be the last task to be accomplished.

Our airplane currently has most of the wing spar parts (center and outboard) made. The spar is currently waiting on the cutting of a few parts with the CNC plasma system. We have the vert stab subkit built. The current goal is to make up the horizontal stab subkit, get the needed wing spar parts made, get the wing spar installed to the wing jig and press out the wing ribs by the end of the year.

So, there it is. We hope this helps to outline where we are here at Prowler Aviation. On to the update.

1. Hydraulic Press - To reach the goal of getting wing ribs pressed out by fall - a press would be helpful. So, this past two weeks we fabricated the hydraulic pump unit and installed it onto the press. The hydraulic ram had been refurb'ed previously and the pump unit was hooked up to it. We added a 40 amp 220volt circuit and a motor controller and presto - hydraulic press. Here's the pic:
The hydraulic pump is only good for 1500psi. However, the piston in the ram is 5 inches in diameter and that gives an area of approximately 19.6 square inches. This gives almost 30,000 lbs of pressure from the ram. Spread that force out over an average part area of 300 square inches and it figures out to about 100psi. Should be more than sufficient to fold up some 0.040" type O aluminum. Next comes the learning curve associated with actually pressing out parts. In particular, keeping the male and female dies lined up with the flat blank that will become the part as the press does its thing. More to follow.

2. Bridgeport Mill - It took a while to get the mill cleaned up and order some parts needed to fix up the mill a bit. The most interesting was replacing some head bolts. One was broken and one was beat up a bit. The change was fun: We got the mill moved into position, hooked up with 3 phase power and have even used it already to machine some slotted holes into some brackets for the CNC table. The 3 phase power comes from a rotary phase converter. We purchased a phase converter panel from Wyn Phase Converter and Supply (http://www.wnysupply.com/index.cfm) and scavenged a 3hp idler motor out of an old air handling unit from the local industrial surplus place. We had a little problem with the delivery of the phase converter panel. Apparently some components shook loose during shipping and managed to beat-up the rest of the components in the panel along the way. Here's what it looked like at delivery: Not wanting to wait the time that would be necessary to return it and wait for a new delivery, we set out to put the pieces back together. With the help of screws, glues and bailing wire we got it put back together and installed. It turned out well. Total cost for the phase converter was ~ $200. Here's a shot of the final rotary phase converter install: Here's the mill pretty much ready to go:
3. CNC Plasma Table - This project has been a long time in the works, but it will hopefully be the centerpiece in being able to practically and efficiently cut parts for the airplane. We've determined that upwards of 80-90% of the parts for the airframe are made from flat pieces of raw stock. After a bunch of research we decided to pursue this process as a means to make our parts. After more research we found that to use a plasma system to cut thin material requires a system that can automatically control the height of the torch. This provides the best cuts, maximizes the life of consumables and prevents wasting raw materials. To that end, we needed to make several modifications to our CNC table and torch systems to get the best chance of getting good parts. We've covered most of these in previous updates and are getting close to the big "first cut." The latest mod was to replace the signal generator (2-D box) that came with the Torchmate system with a new box (MP3000) that has 3-D control and auto torch height control. In fact, it's digital torch height control that is fully integrated with the X, Y, and Z motions axises.This box also, however, requires the use of a new software control system to control the table motion. You can check out the box details here: http://www.candcnc.com/ Look for Digital Torch Height Control. The software is Mach3 and it is an open source software that CandCNC has optimized for use with it's MP3000 system. You can check it out here: http://www.machsupport.com/.

Overall, the modification has been pretty straightforward. The hardest parts were actually installing the Mach3 software and getting it to run on the computer (various issues) and getting the new MP3000 box to interface with the Torchmate supplied motor controller box. We could have just bought new motors, controllers, power supply, etc. from CandCNC, but in an effort to get the lowest cost system possible, we wanted to use as much of the Torchmate system as possible. With enough research and help from CandCNC we were able to figure out the correct translation of wires to get the two boxes to work together. A quick re-wiring of the female DB-25 connector in the Torchmate motor controller box allowed the use of a simple 25 wire parallel computer cable to hook the boxes together. The box and software are installed and the table is working in all three axis's We also installed the digital torch height control system, but so far the test has been unsuccessful. Didn't have time to troubleshoot further before having to head off to the day job for the week. More to follow. We also made several "tweaks" to the CNC table to improve the accuracy. These included adding bracing, re-mounting the X axis motor and shafting, re-meshing the X axis rack and pinion gearing, and adding more Y axis cam followers to support the new floating torch holder. Here's the slotted bracket mods to the Y axis carriage plate for the cam followers to be added to. All these mods have greatly increased the rigidity of the CNC table which will ultimately lead to much more accurate parts. Unfortunately, we didn't get a pic of the overall CNC table with all the new mods. We'll post one next time.

4. Builder's Updates - A lot to report here too.
Kit #1 & Kit #13 - Rick has updated his Prowler site and moved it to a new web address. Check it out here: http://www.prowlerjaguar.com/
Kit #5 - Currently owned by George Morse. It is still for sale. You can see pix of this aircraft on Rick's site (above). We did an engine run-up recently and all is running well.
Kit #7 - Bryan's work continues.
Kit #10 - Ray has installed all the autopilot servos, gotten a new hydraulic accumulator, and cut his instrument panel and cut holes in his side panels for instruments. On the last visit, we dissected and spec'd out the propeller spinner and the radiators. Thanks Ray, nice work!
Kit #11 - Ben has opted out of the Prowler program. Cabi is brokering a deal to purchase Ben's kit and ship it to a new owner in France! In the next update we'll be introducing the new owner. The Prowler has gone global!
Kit #12 - Ray sent the following update on Chuck and his Prowler. In Ray's words: "Chuck flew first flight #2 this weekend. He said the plane handled well and the gear retraction went right. Chuck said the flight only got around the pattern once, the coolant temp went back up to 240 again, just like the last time, and the low oil qty light flickered. George said he didn't have any ideas about the coolant temp, but the oil might be low, and raise the quantity to 12 qts instead of 10 because there is a lot of oil trapped in the accessory case and almost as much in the prop and gear box." We are happy for your partial success Chuck!
Kit #13 - See Kit #1 above.
Kit #14 - We just found the following comments that Steve left after a recent blog update. Here it is in his words: " Hey Todd and company, Thanks for the news. I was able to test fly my airplane #14 late last November and I'm happy to report that my cooling issues are solved. 1.6 hour flight, no squawks.I cut a 4" by 5" square hole near the back lower corner of each of the small removable cowls that cover the exhaust pipes and covered them with stainless steel louvers. These allow air to exit the cowl, which draws air through the forward oil cooler, around the pan and out, and also allows the hot air coming out of the supercharger waste gate to exhaust overboard. The oil temp stabilized between 180 and 200 degrees, and was controllable with the cooler door on the aft cooler.I'm now just waiting for good weather in the pacific northwest to continue flight testing. More news to follow in early spring." Congrats and thanks for the update Steve.
Kit #16 - Bud has been working on tailwheel issues. We're planning a visit to meet him and see the plane later this summer. We'll update then.
Kit #17 - As mentioned above, Cabi has been brokering a deal with Ben's former kit. He also a some exciting news that we'll be able to tell you about in the next update.
Kit #18 - WYSIWYG!

Well, that's it for this update. There is always more, but it's almost 11pm with an early 4:30 wakeup tomorrow. Hope you have enjoyed the new info. Thanks for stopping by to check up on us! Happy Easter to all.

Continuing to (Re) Build Production

Hello again, and thanks for checking back in on us. In this update:
1. Hypertherm Powermax 1000 Plasma Torch
2. Compressed Air Filter/Dryer
3. Floating Torch Holder
4. Bridgeport Mill
5. Builder Updates
6. The 25 Year Old Macintosh Plus

Here are the details:
1. Hypertherm Powermax 1000 Plasma Torch - After a long and patient search we finally located the plasma torch that we were looking for. We found it for sale on Craigslist in the Sacramento area. Hypertherm is one of the original plasma torch manufacturers and they make an excellent product. The Powermax 1000 has a great range of cutting capability with the current adjustable from 20 amps to 60 amps. This should give us the ability to cut thin 0.040 aluminum sheet all the way up to 1/2" thick steel plate.

The first order of business was converting the handheld torch to a machine torch set-up. Using some ideas from the internet this was a pretty straightforward conversion. It turned out very well at a much, much lower cost than purchasing a new machine torch and leads. A new machine torch setup runs $600-$800 and we accomplished this conversion for ~$20.

Now we just need to purchase some new tips and consumables for the machine torch. Hypertherm is making a new line of consumables that they call their "Thin Cut" tips. They have been having good success with these tips and they have apparently been getting good reviews from customers. More on that when we get the machine cutting some metal.

2. Compressed Air Filter/Dryer - Reading the forums about plasma cutting, it has become readily apparent that you have to have dry air to have good success cutting with plasma and to get decent consumable life. To that end we bought a desiccant air dryer, a filter, regulator and bunch of air plumbing to come up with this application. It's all mounted on a recycled teletype cart to provide an "all-in-one" place for the torch box, filter/dryer, and cords, etc. In addition to this setup, we spent a day plumbing compressed air to the other side of the shop to supply the air to this cart. Another day was spent running an 8 gauge 40 amp electrical circuit over to the other side of the shop to supply power to the plasma torch. 3. Floating Torch Holder - In preparation for adding the automatic torch height control, we need to have a floating torch holder. These are for sale online, but some cost as much as $1700. Using ideas gathered from several designs found online, we put together our own torch holder. Here are some pics of the assembly. Just before leaving for work this last time the UPS truck delivered the leadscrew and stepper motor that will do the Z axis movement. Here's a rough idea of how the leadscrew will be placed into the unit:Once we finish the torch holder the next step will be to purchase the auto height control electronics and software and convert our TM1 table to a Mach3 table. We'll still use the TM motor control box, but it will now be controlled by the Mach3 software. This setup will give us true, digital, full 3D toolcut path capability (and arc voltage height control). More to follow on this.

4. Bridgeport Mill - Since buying the company from George, he as been telling us that we need to have a mill. Well, recently a buddy called and said that he'd found a "smokin' deal" on a mill on Craigslist. To make a long story short, after renting a drop deck trailer and and putting in and 18 hr day (that included a trip to the San Franciso Bay area), we now have a gently used Bridgeport mill. While it still needs to get hooked up to 3-phase power (need a rotary phase converter) and we need to get the necessary tooling - we now have a mill. Overall, it seems that the mill is in great condition for the price - with just a few minor repairs (and a good cleaning) needed. So far we've spent a day cleaning the lower part of the mill, lubricating the ways, and getting the DRO (digital read out) to work. The DRO sensors were very dirty and needed alignment, but now work great. This tool will be invaluable in producing parts for our first aircraft and is a necessity for making the accessory gear drive and PSRU parts for the engine. More to follow.

5. Builder Updates - Our biggest news on the builder front is that we have had some great conversations with Bud Tedesco, the owner of Kit #16. Bud reports that he is almost completed but has a few items to complete before his first flight. He is hoping to do his maiden flight by the end of 2009. Here are some pix from Bud:

Great work Bud! We also got Bud hooked up with our Yahoo Prowlerbuildersgroup and look forward to learning a lot from him on building the Prowler. Congrats Bud and we are all looking forward to your first flight. Thanks for joining the group.

There has been a lot going on with all the builders recently. We now have had some kind of contact with owners of all but 5 of the original 16 kits that George produced. Recent info:

Kit #1 & Kit #13 - Rick is proceeding with his plans for his two planes. Check out his latest info here: http://www.rocket-boys.com/prowler.htm . Rick has gathered a great collection of Prowler info on his site. Check it out.
Kit #5 - Currently owned by George Morse. It is still for sale. You can see pix of this aircraft on Rick's site (above).
Kit #7 - Bryan Davies is still making good progress. His work lately has focused on several re-designs to address issues that George had made us aware of and issues from several builders. These include the tailwheel strut, a negative G mod to the fuse-to-wing junction, hyd cylinder attach brackets for the MLG. More to follow on these - but thanks for the great work on these areas Bryan!
Kit #10 - Ray is continuing to make great progress on his airplane. He's recently installed autopilot servo motors and is working on his avionics/panel installation. He just received his UMA engine gauges and reports that they are very nice units.
Kit #11 - Ben is in the process of gathering up all of the outstanding parts he needs after completing an inventory of his kit. He is working with Bryan to buy many of the parts he needs that Bryan has available. The rest we will be working on with Ben in the coming months.
Kit #12 - Chuck should have recently flown his airplane for about an hour. He was planning to do it in the next couple of days as reported by Ray. We'll report more when we hear about the flight.
Kit #13 - See Kit #1 above.
Kit #14 - Steve has fixed the issues with his Prowler that came up in the initial flights. He should now be able to enjoy flying the plane and the hard work that went into building it. Congrats Steve.
Kit #16 - Welcome Bud. See above.
Kit #17 - Cabi has been doing a lot of work on creating his drawings for using his plasma cutter to cut his wing spar parts. In a recent email from him he says that he was about to strap a Sharpie to his plasma table and test draw his wing spar parts to check them for accuracy. We'll report more on this later. On another note, Cabi will be part of a feature article in the March issue of "Flying". He is also going to be in a BBC production on the U2 which will air this summer in July. Keep an eye out for that. Nice work Cabi.
Kit #18 - These jokers can't seem to get anything done on their airplane. Seems that they've been blowing all their time and money trying to get some defunct kit airplane company going again. What are they thinkin'??

6. Macintosh Plus - When we got the company assets from George one of the items included was an old Macintosh Plus computer. By "old" we mean really "old." Do you remember "boot disks?" Well, there was also a pile of old 3-1/2" floppy disks. Turns out that there is some good info on some of these disks. Mostly it is just good "history" info that may someday be useful. In any event, we're spending any "extra" time we have (yeah - right) to print out these old files. Using this old clunker has given us renewed appreciation for today's computers. It takes about 15 disk swaps and 15 minutes to print out just one average sized file on the old Macintosh dot matrix printer. But, it's also kinda fun - like archeology.

Thanks for stopping by.

Happy New Year From Prowler - Big News!

As we begin 2009, we have some big news to share about Prowler kit and aircraft purchases.

In this post:
1. Purchase of kit #11
2. Purchase of the Red/White & Blue aircraft and kit #13.
3. CNC update
4. Builder reference pix
5. Builder Updates

Thanks for checking in and let's get started:

1. Purchase of kit #11 - According to our records, the "Old" Prowler Aviation produced 16 aircraft kits. These kits varied in completeness. Some were complete kits, several were not all that complete. In any event, kit #11 was a fairly complete kit owned by an individual in Prescott AZ. This kit was posted for sale on Barnstormers late last year and was purchased by Mr. Ben Armen. Ben is an airline captain living in PA. He as since taken possession of the kit, set up for initial assembly in Austin, TX, and has inventoried the entire kit. Ben has lined up assistance from old friends in Austin that will be helping him get started on his kit. Congratulations Ben. We look forward to working with you and assisting you in the building of your airplane.

2. Purchase of RW&B aircraft and kit #13 - As we previously reported, the second flying Prowler (Red, White & Blue aircraft) was owned by an individual in Jacksonville, FL. This person also owned kit#13. Mr. Rick Pellicciotti of Memphis, TN has purchased the kit, the aircraft and all of the Prowler parts and pieces from the JAX owner. Rick and his wife have moved all the Prowler "stuff" to Memphis and he has begun his inventory as well. Here are some pix of the move:

See Rick's website link (on the right side bar) for more information. We look forward to working with you and assisting you in getting your aircraft back together and kit built. We will post more about his plans once he gets his inventory done and has had an opportunity to come up with a game plan. Welcome aboard Rick.

3' Progress on CNC table - We have been spending a lot of time "burning electrons" on CNCzone.com (a great resource) and are getting a lot smarter about CNC tables and plasma cutting. As a result we have determined several modifications and options that we must add to our CNC table. The list includes: 1) add cable guides; 2) modify torch holder from a "manual" torch system to a "machine" torch system; 3) add an automatic torch height control system; 4) actually purchase and add the plasma torch to the table. Well, we took baby steps on this one and started with the easy one first:

Cable guides are now installed and table tested. No more wires hanging off the ceiling!! The torch holder system mod is up next. Here's the "manual" torch holder before removal:
We are investigating modifying this to a "machine" torch holder that will also be able to be used with the torch height control system. More to follow. Here's a pic of the current setup:

4. Builder Reference Pictures - Over the past several months we have had the opportunity to visit and work with builder Ray Seim. He has made his collection of Prowler pictures available to us for other builders to use as reference when working on their aircraft. These photos are of several of the completed aircraft and current kits at various stages of construction. It also contains many pix of single components being constructed which are very useful for builder reference. We have spent hours scanning and organizing these pix into a CD to distribute to our current builders. Many thanks to Ray for these photos, we really do appreciate this contribution. These will, without a doubt, be very valuable to our current and future builders!

5. Builder Updates - Here's a recap of the current builders that we have had contact with and the status of each aircraft:

Kit #1 (RW&B Aircraft) - Recently purchased by Rick and is currently being inventoried and developing a game plan to re-install engine and get the aircraft flying again.
Kit #5 - We recently discovered that George's 3rd aircraft appears to be kit #5 that was returned by a former owner. Airplane is airworthy, has flown, but is currently in "storage" and is for sale.
Kit #7 - This kit belongs to Bryan and has the wing almost completed. Bryan is getting ready to begin assembling the fuselage.
Kit #10 - This kit is owned by Ray and is in the 80% complete range. He is currently working on installing avionics and hopes to get the engine installed by the end of the year.
Kit #11 - This kit was recently purchased by Ben and has been moved to Austin, TX where it has been completely inventoried. Assembly will begin over the next several months.
Kit #12 - This kit is owned by Chuck and has flown. He is working on taking care of some issues and preparing another round of test flights.
Kit #13 - This kit was purchased by Rick at the same time that he bought the RW&B airplane. This kit is (in his words) "the 75% complete and 75% left to go phase." Inventory is underway and he will have a plan for this kit in the future.
Kit #14 - This is the airplane owned by Steve and has flown it's maiden flight with some follow on test flights. At last contact, Steve said he was working on some cooling issues and would be flying it again soon. That was late last year and we need to check in on Steve again soon.
Kit #17 (Sort-of) - This aircraft is being built by John "Cabi" Cabigas. We are calling this kit #17 since John purchased many left-over inventory parts as well as the engine and landing gear from George prior to our purchase of Prowler Aviation. His aircraft will be a collection of these parts, parts that Cabi is fabricating himself, and possibly some from us. Since it is still following George's techniques we are including it into the "Old" Prowler Aviation kits - as we are also doing with our kit.
Kit #18 - This is the kit that we are building. As mentioned above, we are including it in the "Old" Prowler Aviation kits since we are also using some left-over inventory parts from the old Prowler as well as our own parts that we are fabricating using George's techniques. Once we are actually set up for production - we will most likely switch to using some new kit numbering scheme. More to follow. We have a vert stab sub-kit that is being assembled and the wing spar is in progress. Total work probably represents less that 5% complete.

That's the latest and greatest. We work full time on this project when we're not working the "day jobs" so that we can get this company back up and running. We appreciate your keeping tabs on us and your support. Have a great 2009!

THE PROWLER GOES DIGITAL

The topics of today's post: We've got a CNC table, Builder Contact.

CNC Background - After building the sub-kit for the Vert Stab recently, my focus in NorCal has shifted to getting the wing spar (center section and outter sections) into the wing jig. While Dave is back in FL practicing his riveting so he can start the vert stab assembly, I have run into the need to fabricate several steel pieces for the wing spar. Faced with the prospect of having to hack these parts out buy hand or trying to get set up to do these parts with a plasma cutter - we opted for the later.

If you recall, I mentioned in a previous post that John "Cabi" Cabigas is also building a Prowler. In fact, here's a link: http://prowlerjaguar.blogspot.com/ . Cabi bought a CNC plasma torch a while back and I contacted him about making some of these parts. Turns out, he had already modeled several of the parts that I need to have made. One of the biggest pieces is the wing attach plate that is bolted to the center wing spar and us used to attach the outter wings (at the spar). These are the pieces shown on the right here:

We found a day we both had some time and I went to visit him. We spent the better part of a day trying to flatten the "learning curve" on using his setup. The parts are still being worked on, but after seeing his machine work I realized that this is the way to go - when it comes to producing Prowler parts.

Buying The Table - Dave and I discussed this topic for some time, weighing the pros & cons. In the end we decided to pursue getting out own CNC plasma set up. We started looking at the different companies and their machines. We found that their systems vary wildly in both cost and capability. Cabi has a PlasmaCAM system. It's a good system that comes standard with many features that are options with other manufacturer's systems. In the end, we were leaning more toward the Torchmate system. We were going to purchase a new 4' x 12' TM1 system, but found a used 4' x 8' system for sale in Fresno, CA. After nearly a month of negotiations, we purchased the used system. Turns out, it was very well built, it was hardly even used, it was fairly priced, and it is expandable to a 4' x 12' system. Here are some pix:

The table came with the computer setup, but has had the hard drive reformated and a new operating system installed. The monitor has been replaced with an LCD monitor. We still have a lot more work to do before this becomes a useful tool in the Prowler shop. First off, we still have to purchase a plasma torch for it. I have been trying to learn how to use the software and I'm having some modest success. I have modeled my own "sample" part using the Torchmate CAD software. I have exported this file from the CAD software as a .dxf and then imported it into the Torchmate software that actually runs the machine. This software converts the "sample" part .dxf file into something called "G-code" which is what actaully makes the table move in the correct way to cut the part.

The Production Plan - While we were discussing the purchase of a CNC plasma system, we reviewed the parts breakdown of the Prowler and came to the determination that upwards of 95% of the basic airframe parts for the Prowler are made from 2 dimensional patterns. These parts are then either bent up into shape, or are in some way welded or attached to other pieces to form a larger part or assembly. So, our goal is to go forward and use this system to build our first airplane with the result that when we finish we will have modeled each part of the airplane for future use. Essentially we need to turn each of the patterns in these boxes:

into one of these (a sample part file in Torchmate software):
When we get ready to make another airframe, it should simply be a matter of putting the metal in the machine, pull up the files, and hit enter. Without having done any in-depth research, the hope is that we (using our system and Cabi's system) will be able to satisfy our production requirements - when we get to the point where we can start selling airframes.

Builder Contacts -
Ray Siem - We have stopped by again to visit Ray. He has made some significant progress on installing the systems back onto his airframe. He has installed the fuel and hydraulic systems. His main and tail landing gear are installed. He is in the process of making final decisions on his instrument panel and systems. Compare these pix with ones from a previous post:

Ray has an extensive collection of pictures that he has taken while working on his airplane. His pix are a collection of shots of George's , Chuck's, and his airplane. They are a great reference for building one of these airplanes from scratch. We are in the process of scanning all these pix into data files for computer storage.

Chuck Westcott - We have a meeting sked with Chuck for Tuesday, Nov 25th. He is based at the Salinas, CA airport and is planning on the second flight of his Prowler just after Thanksgiving Day. We hope to be there when it happens to learn as much as we can and document the occasion. More to follow.

Bryan Davies - Bryan's mother has passed away recently. Our sorrow and condolences go out to you for your loss Bryan. He has had to put the Prowler on hold for a while while he works on settling his mother's estate.

Steven Rogers - We (including Bryan Davies) had planned to go visit Steve in Sept, but had scheduling problems. Once Bryan is ready to go again, we will work out trying to schedule a visit to see Steve. We are really looking forward to the visit Steve!

That's the big stuff for now. Thanks again for checking in on us.

VISIT TO A BUILDER, WING SPAR PROGRESS

The topics of today's post: A visit to a builder; building a drill press bench; and progress on our center wing spar pieces.

Builder Visit - One day last week while sitting on-call Todd took a trip to visit a another Prowler builder. He went to see Ray who is building one of George's original kits and lives near Thousand Oaks, CA. Ray has been working on his airplane on-and-off for some time now, but the quality of the work is astounding. His precision and attention to every detail is producing the best Prowler we've seen so far. Here is a pic of his airplane fuselage in one of his garages:

The airplane is actually much closer to completion than it looks here. This is because most of the rest of the airplane parts and systems have been completed, fitted, removed from the plane for painting and then stored in one of his many shelves of boxes. He is hoping to finish the re-assembly of all the components to the airplane and have it out of the jig within the next year.

Ray has been already been a wealth of information about this airplane and provided us with much more insight about the aircraft. After talking with him, we found out that another builder has flown his Prowler. Chuck is also a builder of one of George's original kits and is in the San Francisco Bay area. We look forward to getting together with Ray again many more times. Great work Ray!

Center Wing Spar Progress - Now that Dave has a sub-kit to keep him busy in his shop, Todd has had some time to work a little more on the wing in his. If you look back in the posts, it been almost a year since we cut out the pieces for the center wing spar. Hard to believe that this much time has gone by, but now we're making more progress. After cutting with a metal band saw, the edges of all the spar pieces are left with a fairly jagged edge, so they needed to be trimmed up. Here's a pic from last year's post: Also, the pieces were scribed to the pattern and then cut just outside of the scribe lines. This leaves enough material to file down the edges to a smooth finish. Turns out this represents a lot of filing. So, on to a better way.

Sometime after cutting out the spar pieces last year, we mounted a router under one of our building tables and fitted it with a 3 blade, carbide tipped router bit with roller bearing on the end. This provides for a technique to clean up the edges of our spar pieces (raw stock) and make them match the patterns exactly.
Here's how it works:
1) Mount the router and put it in the straight cutting bit;

2) Cut two 1/4" spacer strips for each pattern. One spacer strip goes under the entire stack and provides room to have a counter-sunk bolt head. The other is to provide room between the roller bearing (that rides on the pattern) and the actual cutting part of the bit . This keeps the pattern a good distance from the cutting edges and prevents chewing up he pattern. See pic in item 4 below.
3) Drill selected holes into the raw stock using the pattern/drill guide:
4) bolt the "stack" together and adjust the router depth to get the correct height for the pattern to ride on the roller-bearing: 5) Make a ba-zillion tiny bits of aluminum foil and end up with the whole stack looking like this:
The next item to work on are the bearing blocks. They are rectangular blocks that surround the bearing and are clamped under the wing attach brackets.

Drill Press Bench - A small side project that needed to be done was to create a long bench with a drill press attached for drilling the numerous holes that must be drilled into each wing spar piece. A long bench is need to provide support for these floppy pieces of stock while being drilled. This was the solution we came up with:
By mounting the drill deck (table) under the bench top the drill can just penetrate into the bench top and (most importantly) the head of the drill press is now height adjustable above the bench top buy loosening the drill deck handle and adjusting it.
Make sure to square the head of the drill press to the bench top. We used a tri-square and make adjustments (shims if necessary) to get the press square to the bench top in both directions. It has worked great.
Another side project that is getting more and more necessary is a hardware/parts bin rack. We found an old bread rack dolly for $10 and have begun modifying it for parts bins.

Contacts - Todd and Bryan were supposed to go up to Seattle to meet with Steve who has the 4th flying Prowler this weekend. Unfortunately, scheduling issue came up and we weren't able to coordinate. We are going to try to resked the visit for sometime in Oct.

Thanks for checking in on us.

VERTICAL STAB & MORE

Welcome! Or, if you're keeping tabs on us, Welcome Back!

Well, we're managing to get another update done - and it's only been weeks, not months! But, that's because things are happening! Here goes:

Inventory & Parts List - It's taken several months to complete, but we now have a fairly accurate and fairly complete inventory of all the "stuff" we got from George. We have organized this information into a set of Parts List spreadsheets for the airplane. We now have one comprehensive document that contains information about each and every part of the airplane, what its name is, what it's pattern or template is, what it's material specification is, etc., etc. There will be changes, additions and subtractions to this set of documents as we progress, but it is a baseline to start from. Amazingly, this had never been done before, and until now all this information was scattered about in various places - or just didn't exist.

One of the biggest challenges was going through all of the old documentation and finding items that were represented as one part, but were actually made from several different parts and pre-assembled. For example, there is a short shaft that the gear are mounted to. It is "anchored" in the torque box and protrudes through the wing spar. In the old documentation, this was represented as one item. It is actually made from 8 different pieces of raw stock. For production, this information is important to know because it will affect material ordering, etc. Now we will be able to tell exactly how much 4130 (0.063) sheet steel is required for one airplane, for example.

During this process, we also accomplished two additional tasks: 1) matched up any left-over inventory with the patterns that they came from; and 2) divided all the inventory, parts, patterns etc. into seperate boxes (for now) for quick reference. So, we now also have a fairly accturate list of inventory we got from George in the sale and now know where to find it!
Vertical Stabilizer Sub-Kit - Armed with the new spreadsheets, we now have an idea of what inventory items currently exists in each sub-kit and what we will need to fabricate to complete an airplane. The first sub-kit on the list was the vertical stabilizer. Turns out that we had all but about 4 parts we needed to pre-assemble this sub-kit. As mentioned in the website, Todd is the "Production Guy" and Dave is the "Assembly Guy." The vert stab sub-kit has been produced and is now in final assembly. Dave will be doing a major over-haul on the assembly manual as he completes each sub-kit. So, in the end we will have a completely revamped builder's assembly manual.

The parts which needed fabrication included the vert stab skin, a mid-rib, a forward spar and a small angle clip. We used a vacuum bagging technique to fold and crease the skin, a break for the spar parts and the old fashioned "bang it out" technique for the mid-rib.

George came out to help get us started and guide us through the "jigging" process the first time.

Once that was done we drilled the skin and built a crate to ship it to the "Assembly Guy" - Ah, I mean Dave. Now it's on to the fabricatiion and pre-assembly of the horizontal Stabilizer sub-kit next.

Materials For the Plane - Over the past several weeks we have been sifting through the newly created spreadsheets and determining materials that need to be ordered to complete the first two groups of sub-kits. This material has been amassed and is now holding down a bench in the production shop.
This is the steel sheets, steel tubing, bearings, hardware, etc., needed to assemble the Tail Group Sub-Kits and the Wing Group 1 Sub-kits. Hard to believe, or maybe not, that including shipping this pile of stuff represents over $1K worth of materials. In some cases there is enough material to make more than 1 airplane, but some things have to be bought in a minimum order - so that's what ya get.

Contacts - We have contacted a few gents recently that are currently building, or have built a Prowler. In fact, we are going to visit Ray in the Thousand Oaks, CA area to see his project tomorrow (Sunday, Sept 14th). We can't wait, as he sounds like a really nice fellow. We have been very encouraged by some of the information Ray has given us with reference to the airplane, and several folks he's been involved with for the past (nearly) 20 years who know the Prowler and have information about it. We're sure we'll have a lot of info to put into a blog post after meeting with him. Much more to follow.

Also, as mentioned in an earlier post, we have been in contact with Stephen in Seattle area who has a flying Prowler. Bryan and Todd are going to visit with him on the weekend of Sept 20th. This is sure to be a major event in the process of expanding our knowledge of this airplane. Steve is an engineer in the field of airplanes and should have a lot of pertinent information to help us. Much more to follow here as well.

Thanks for stopping by. We'll try to get a post out after meeting the two fellows and tell ya what we found.