Source: 1999 Beartracks, Bob Barrows

Bob,

Thanks for the note of 10/17 and yes, the struts arrived safely this time. The outer wrap had a small tear that didn’t penetrate to the metal.

I usually work on the Bearhawk between 10 am and 6 pm with the odd interruption to run into Kent (South of Seattle) to Boeing Surplus, a good resource for used tools, new aluminum and such. I just picked up a 61″ x 151″ x .125 sheet of 2024T3 for $185. I am cutting main spar caps, splice and filler plates and attachment plates from this. The savings more than justify the 225 mile round trip.

I have joined the local 430 EAA chapter, but have not yet met the tech counselor. I will have to get them over here soon as I am close to completion of ribs. The spar blanks are ready, caps, slices, and other necessary parts should be cut this week-end so that riveting can begin. The 1/2″ x 1/2″ angles need cutting to length and riveting too.

I took time out to turn a set of punches and dies out of firewood (Alder, Maple, Madrona) to form lighting hole flanges. The photos show a couple of them and the drill press used as an arbor press.

I am ready to order the remaining aluminum needed and the 4130 tubing. I want to talk to some of the other builders in the state to see if my buying plan is viable. I bought the first batch from Airparts in KS and enjoyed their rapid and professional response. Cost are reasonable too, in my judgement.

Enclosed is my check for next years Bear-Tracks, an enjoyable and necessary adjunct to the plans. I am having FUN! Mostly because of the loving support of my wife, not to mention Dan Donovan of All Form Welding, who has given me free run of his shop and Joe Ritter, who has made his shop (2 doors away) available as a good neighbor! Now – if I could just line up a good bucker. Best Regards,

Jack Piggott – #347 – Sequim, WA

Dear Bob and Mike,

Enclosed is my renewal check for Bear-Tracks and a photo of my Pile-O-Ribs. After finishing the ribs, stiffeners, attach angles I got got tired of forming aluminum and have been having a good time making some of the flat 4130 pieces for the wing hardware. I am hoping to run out of my last order of material about the same time I start my flying lessons in early ’99.

I do have one question for you – I’ve looked over the plans and newsletters and can’t seem to find any detail on the tail spring anywhere, other than how to attach it. Did you make the spring, or is it a salvage unit from a production aircraft? The reason I am asking so far in advance of needing one, is if time allows I plan on doing some parts scrounging while I am in the states and have been making a list of items to be on the lookout for.

After further examination of the new struts and the revised drawing, I think an additional thank-you is in order for making them available to your builders. I really was not looking forward to making and attaching the original design fittings. I’ve constructed a substantial crate to store my struts in so that they should be safe until I need them.

Del Rawlings – # 316 – Cordova, AK

Del,

Thanks for the photos of your wing ribs, they look nice. Regarding the tail spring, I used some that were found at the airport here. It depends some what on the tail wheel you use. Also if you can’t find one that will work – you can have it made at a local auto spring fabrication shop. I will be providing more information on this subject in future newsletters.

Also we are now testing a homebuilt tailwheel assembly we designed and built. If it continues to work as good as it has been we will provide drawings for same with spring details.

~Bob

NOTICE: In an effort to get builders to send in photos of their projects we have decided to try and bribe you guys! Starting with the October issue if you send in a photo of your project your name will be put in the running for a very nice BEARHAWK HAT! We do not care what stage of construction you are currently at – we would just like to see your progress. Even if all you have done is your wing rib form block send in a photo!

Bob, Well after many other projects finally out of the way #235 is under way! The shop is heated and finished, my first shipment of aluminum is here and I have started cutting out nose ribs. The aluminum sure is a lot cheaper when I buy it through work at wholesale prices. It is less than half what I’ve seen advertised for. Sorry that I missed you at Oshkosh last year, I was only there for 10 hours on a charter flight. I did speak to Mike briefly, sounds like it was a great trip to Alaska. If you decide to come look at some land up here (your dollar is still valuable) drop me a line. I’ve enclosed an international money order for the newsletter renewal.

Mike Guthrie #235 – Ontario – CANADA

Hi Bob, I have a question about building the control surfaces I hope that you can answer. What kind of a jig did you use while assembling them? I am trying to build the ailerons, but keep having to start over, trying to keep everything straight and aligned. Any kind kind of suggestion you can provide would be appreciated. We are almost done riveting the skin on the left wing.

Pat Fagan #232 – Pearblosson, CA

Pat, Good to hear that you are progressing smoothly on your wing skinning. We did not build a jig to align the flaps and spars. Find a perfectly level – flat table to assemble the flaps and ailerons. Start out by skip riveting the nose skins along the spar every 4 – 5 holes to keep the movement of the parts to a minimum. Check the fit to the wing and drill out rivets on the top side of the skin and re-cleco and c-clamp as needed. continue to skip rivet and rechecking fit until all rivets are in place. The pull rivers are to go in last. I think that you will find this method to work best with minimum re-dos on the rivets.

From the Internet:

On drawing 20 1 had not closely looked at the tube sizes. I thought that a larger tube slid over the front horizontal stab tube and was welded to it. Now I realize it is two 7/8″ tubes of different thicknesses butt spliced together. Is this the intent? For slightly less than 1 pound extra weight, I will make the entire tube out of the .049 material. This will have the added advantage of being more resistant to rock strikes. I had some nasty dings to patch there on the Maule that I rebuilt. Drawing 16 shows the airfoil shaped trim made out of 1/2 by 1/2 .032 channel, I am wondering what method you use to get a smooth bend around the nose of the airfoil? I have access to a shear and a 12′ brake at work now so I brought a 72″ x 18″ sheet of .032 4130 with me to make all the T25 channel pieces with. They gave me a bit of a hassle about checking it on as luggage on the company 737 but I got it here. In a fit of insanity I agreed to an extra week of overtime, so I am imprisoned at Prudhoe for 3 weeks this time.

Rod Smith #246 – Wasilla, AK

Rod, For the more punishing environment that you will be flying in it is OK to bump up the tubing thickness to .049 – the thicker tubing will be a bit harder to work with and you are adding weight back. Since you plan on a electrical system though the weight penalty should be negligible. As for the airfoil shaped trim piece, it is made out of 1/2 inch channel. Numerous “V” shaped cuts were made to make the bend for the airfoil shape. The notches were then welded together. This trim piece and allows for a tight fit of the windscreen so it is OK to file the welds flush. ~Bob

Bob & Mike, Enclosed is a renewal check for Bear-Tracks and the landing gear shock strut seal and snap ring kit. I enjoyed meeting both of you at Arlington and I am glad to hear that the whole Alaska trip went well. The opportunity arose for me to buy all the tooling and miscellaneous hardware from an RV builder who became ill and won’t be building any more airplanes. I also picked up a Scott tailwheel and other miscellaneous items. I’m real anxious to finish my shop and classic car projects so I can work on the BEARHAWK only.

Wayne Halliburg #266 – Centralia, WA

Hello Bob, Another year has come and gone and more BEARHAWK parts are being made. After a short slow down to add on to the house and other “little” things I am now back at work on my project. I spent 8 hours on a Bridgeport milling machine last week squaring and cutting to length all the web supports (1/8 x & 1/4″) for both main spars and next week I will do the same for the rear spar. We squared up the inner front attach plates and I laid them out and they went together easy, the jigs for the spars should be simple. I ordered the fiberglass wing tips from T.Q. Fiberglass.

April 12th will be 2 years into this project, but I’ve only got about 330 hours into it to this point. As for powering my BEARHAWK I’m leaning towards the Franklin 205 HP engine, everyone that I’ve talked to seems to think a lot of them.
I was glad to hear your trip to Alaska was a success and I enjoyed reading about your adventures in the newsletter.

Sonny Cilley #234 – Royalton, VT

Sonny, Good to hear that everything is going together so well. It looks as if you are keeping a good record of your build time and you seem to be right on track hour-wise to a 2000 hour build time. If you just find a couple of hours every day you will get more done than trying to work on it 8 hours on one day.
We found the T. Q. Fiberglass wingtips to be of first class quality and hope that you do to. Let us know how you like the quality and the service that you received. -Bob.

Howdy:

Just set up the jig for my wings today. Took the whole day to get everything square and level. Will spend next weekend finishing and fitting the fuel tank and determining where the holes for the lines will go and double checking the fit of the tank straps and then, finally, I will put the 1st wing in the jig.

I had, as did others, a problem with the aileron cable at the pulley located at the web splice that takes the cable down the wing strut. I solved the problem by clamping the bracket to a solid work bench with 2 LARGE c-clamps. Then I tapped the top of the bracket with a hammer just a bit in the direction that was needed. When I reinstalled the bracket and pulley, to my amazement it lined up dead on. It only took a small tap as the misalignment is very small.

Tim Neil – # 209 – Uniontown, PA

Tim: Thanks for the update on your wing construction – you should really enjoy the skinning process as it progresses.

Regarding the pulley/cable line up. I have investigated this problem and found that the bracket as drawn on the prints is not located properly. This condition has been in use on the prototype and has not shown a wear problem yet. Your fix sounds like a simple effective way to modify the bracket for the builders who have already made this part.

I will be working up an engineering notice on the bracket in the next issue of BearTracks. ~Bob

Mike and Bob,

Would like to thank you for taking the time to show me the BEARHAWK. I’m sending you the info I have on procuring alodine. You can order the crystals from a chemical supply house for approximately 30 dollars. It will probably last you a life time or divide up cost among people you know. Alodine is chromic acid and you can normally get it in clear or yellowing. I use the yellowing to verify coverage. I believe I found this info in Sport Aviation (August 96). 1 tore out the page and I’m no longer sure which aviation mag it was out of. If you have problems locating supplier drop me a line. Best of Luck

Chester Abbott Ocean Springs, MS

To BEARHAWK dreamers and doers,

I had the pleasure of spending the holidays with Russ (Erbman) and his family. I also had the distinct pleasure of helping with the riveting procedure on the rib stiffeners and the wing spars.

You must realize that I was trained (50 years ago) to SPRAY EVERYTHING WITH ZINC CHROMATE primer. I have seen the development of epoxy primers. In both cases solvents are needed for cleanup. I don’t care what anyone else says, I DO NOT want aircraft solvents around a house that my grand children (and their mother) live in.

I had difficulty reminding myself that the white parts were primed and not top coated. They were not green.

I may be prejudiced, but Russ did a beautiful job of spraying the parts. I was impressed with the working life of the primer when we were brushing a coat of primer on the mating surfaces and then riveting. The sealing of the edges between the cap strips was excellent for the initial seal.

In case you did not catch on, I think the Poly Fiber Primer is Terrific. I forecast that within 5 years after the commercial release of the primer, it will be the most specified primer on new designs in the aircraft industry.

Lee H. Erb, P.E.

Wow – Give you guys a little incentive and you really come through. We had about 10 entries for the BEARHAWK hat drawing. If you sent in a photo – your name got tossed in the hat (the very one that you could win). Mike drew the winning name on Oct. 12. The winner’s name is on the last page of this issue. We will do this again for the January 2000 issue – so send in those photos.

Bob, As per our phone conversation the other day I am sending you these questions as you asked to include in the newsletter.

1) There seems to be a 1 1/2″ – 2″ gap between the wings and the fuselage and I wondered how you went about covering it?

2) With the rear window frame, do you have the outside of the frame flush with the door frame and if so how do you get the window in?

3) On the plans it looks like the aluminum fairing on the landing gear legs only covers to the rear leg. Is the front section covered with fabric? Do you run your brake lines inside the fairing?

4) Could you give me the details of the tail spring, length of spring and height of fuselage from the ground?

5) Do you have your rudder cables run along the lower inside of the fuselage with fairleads and do you use a turnbuckle on each side?

6) How do you attach elevator and trim levers inside the the fuselage when it is covered?

7) How many inspection holes do you have in the wings and what areas and size?

8) By the photo it looks like you have a fairing around the top of the landing gear to fuselage, also top and bottom of the wing strut, are these all fiberglass?

9) With the strut at the front of the rear stabilizer is the top just flattened or is there a piece welded to it?

10) The lead balance weight in the elevator, did you mold the lead piece in place or mold separately and attach later?

Merv Hargraves – #362 – Queensland, Australia

Merv – Thanks for sending in the questions, and the photos of your project. In regard to your questions:

1) I used .025 2024 T3 aluminum to cover this gap. It is similar to the fairing used on a Piper Tri-Pacer or Pacer. Attach to the wing with screws.

2) The rear window frame is just slightly outside of flush to allow the window to slide in.

3) The gear legs are covered with fabric and the brake line is inside mounted on tabs to the rear leg.

4) The tail spring is similar to those used on Maule aircraft. 3 or 4 sections 1 1/2″ wide 1/4″ thick, with the two main sections about 16″ long. The fuselage is 18″ off the ground.

5) Rudder cables run inside fuselage until about 19″ in front of tail post, where they exit the fabric to connect with the rudder horn. I used four fairleads located at Sta C, D, F & H to support the cable.

6) Make an access cover 9″ x 8″ on each side of the fuselage at a location centered on the top longeron and about 2″ in front of the tailpost.

7) 1 used 6 inspection holes in each wing one at each pulley, aileron bellcrank, flap spring attach points, flap arms and the strut attach fitting on the front of the spar.

8) The fairing at the top of the landing gear is .025 2024 T3 aluminum attached to the T25 channel and the .032 fairing support with screws, use rubber edge material around the top of the fairing so as not to damage the fuselage fabric as the gear moves. The fairings at the bottom of the struts are fiberglass (see ad in the back of this newsletter to order).

9) The strut is just flattened, bent and welded around the edge.

10) I molded separately and cut to fit but it could be molded in place if you like.