It's finally "done", the 701 wing repair/extension was completed a couple of nghts ago, but I'm just getting to the blog now. Here's a quick update of what happened Thursday night to finish it off.
Off the table and to be prepped for storage. Ron and I will add some plastic sheeting wrap over the ends to keep any birds out while it's stored in the barn.
I'm so glad to be done this repair/extension, but I can't deny how much I've learned. Now the table is clear and I can focus can be on building my 750!
Stay tuned more to come!
Once again, I find myself disappointed that I haven't been keeping my blog up to date. Almost a month has gone by - if you've been following along, thanks for staying with me.
The last couple of weeks have been busy in the shop, I can honestly say I think we are coming to the end of the 701 wing repair/extension. It's been a very VERY long road, but worth every minute learning how to read Zenith blueprints, bend metal, plan ahead and correct mistakes (both my own and those of the original builder).
In my last blog post, I mentioned we were going to try using the router to cut the 040 thick aluminum sheet. I have to cut 3 strips that will be bent to make up the corner supports of the horizontal tail frame box, and using the bandsaw or scoring method would be difficult at best because of the size.
I laid out the 040 sheet on the table. Unfortunately, I didn't take any pictures of the set up, but essentially I planned to use the same method as I used for cutting the nose skin slots - a long straight edge to guide the router along.
What I didn't expect was the router bit to snap immediately on contact with the aluminum. Frustrating as I was very careful in set up, feed speed, etc. In the pics below you can see it snapped up close to the shank, not down by the tip where it contacted the aluminum. I'm guessing it can't handle the stiffness/thickness of the 040 despite cutting the 016 very easily:
I decided to put this testing away for now - I'm going to have to obtain a replacement bit anyhow. I'll do some more reading/research to see what I can do to improve my chances. I'll have to get back at it soon, I need these pieces for my tail, the first thing going on the bench when we're done this 701 wing.
Back to the wing.
Using the same method as the inboard nose skin, straps and wooden strips are used to bring the skin down tight to the spar and nose ribs. It actually wrapped a lot easier than I thought it would, but careful even tightening of the straps was key.
With the skin in position, I used the hole duplicator and matched the nose skin holes to the spar. Surprisingly, the rivet hole spacing is correct - at least the original builder got that part right.
With the bottom of the nose skin secured, we flipped the wing over to get at the top side. Same process here, straps, blocks and careful tightening.
If you look at the picture above, it's clear I need to trim the wingtip nose skin. It's a complicated curve, even more so than the upper and lower wing tip ends because it also curves from top to bottom to form the shape of the nose.
Adding to the challenge is that the original fiberglass wingtip can't be installed yet as we are using it as a template negative mold to make more.
So, how to cut the skin to match the wingtip nose, without actually installing the wingtip nose? There are a couple of things I can look at for reference.
First, the other wing for this 701 is in much better shape and the wingtip is still intact:
Unfortunately, I'm not going to take the nose skin off the good wing, just to make a template for the wing repair. We also can't assume it's correct - remember, it came from the same builder!
Second reference, the plans! Only problem here though is the plans reference measurements from the last wing rib to various points on the nose skin curve, where X is the distance from the spar line, and Ynose is the distance from the last rib to the point on the curve:
Seems simple enough, but we've added an extension and added two more ribs. So where to measure from, hmmmm.
With the skin in place, I marked the skin where it overlapped the upper spar cap - essentially this marks the end of the upper spar cap and is the X=0 point in the table above.
The nose skin was removed again - clecos from both sides, straps, blocks, and all (the skin had to be deburred anyhow). Now that I had a good X=0 point, I measured back from there 505mm, simulating where the outermost wing rib rib would have been. I made a scribe line from top to bottom at the 505mm mark, then marked out each of the X points. From these I could now mark each of the matching Ynose points on the curve.
To make the line a smooth curve, I connected the points with a french curve drawing ruler. Once i was satisfied I had the measurements correct and the curve was a smooth as possible, I used hand snips to carefully cut away the excess skin. I left it a bit long as it's always easier to trim it back once the fibreglass nose is in place.
Before putting the nose skin back on, I ran a pair of wires from the root to the tip, leaving enough to work with at both ends and correctly labelled. The wires are secured firmly (but not tightly) to the nose ribs by a dual wire tie standoffs.
The other thing we wanted to do before fastening the nose skin permanently, was to rivet in a backer plate behind the wrong slot I had cut. This backer will give us a surface to place body fill putty in the slot.. When it dries, the holding rivets will be ground flush and the nose skin sanded smooth.
The wing skins go back on, the straps are tightened again and the skin lines up perfectly. Clecos are added, and the final riveting is completed on the lower side of the nose skin. The wing finally looks substantially complete!
The next step to finish was to replace the damaged lift strut pickup support bracket. I made a new one out of 032 (the original builder used 025), drilled and clecoed for fit
So, what's left to do? Finish installing the fuel bay cover and rivet the upper side of the nose skin. The upper wing root skin will be done once the wings are installed and wing incidence/dihaedral is set (more on that later).
Very happy to see this wing going away for storage by the end of this week.
Next up, my horizontal tail. Here are the frames for two other 701's Ron is working on. I'm getting my parts gathered and will be building my tail alongside these ones:
A productive couple of weeks. Hopefully my followers here will finally get a chance to see me working on my airplane. I wouldn't be able to even begin without the skills I've learned here on the wing repair/extension. I'm very thankful for the opportunity to learn - that's what it's all been about :)
Been a while since I posted, but the new job is taking up most of my days and weekends are escaping us because now the outdoor work around the house begins. Excuses aren't welcome, but the grass doesn't stop growing.
Much earlier in this blog (my first post actually - click here) I spoke of all the work my mentor Barry Morris and I put into trying to promote and develop the South River / Sundridge Airport. Unfortunately, Barry passed away before seeing the local municipalities get their acts together on this important community asset.
I honestly thought all was lost regarding the airport. Three times the municipality almost sold the property to non-aviation interests who wanted to turn it into a number of non-aviation purposes. How disheartening.... however....
I'm ecstatic to say the property was sold to a couple of business men that are enthusiastic aviation people who want to continue to develop the property PROPERLY as a municipal airport, including paving a runway and installing lighting. "Build it and they will come...." is a quote from the 1989 "Field of Dreams". How perfectly appropriate!
On the 12th of May, the new owners, in conjunction with COPA and the local flying club hosted a fly-in pancake breakfast. Ron, his wife Donna and I attended and joined the fun.
Over 40 aircraft from all over southern Ontario attended, it was wonderful! The new owner couldn't wipe the smile off his face! There are a bunch of photos on the airport Facebook page. I was way to busy chatting with friends to take a bunch of pictures but here are a few:
Of course one of the more interesting planes that arrived was a newly kit built Zenair 750 STOL, just like I'm building. Spoke at length with the owner who has about 80 hours on the airframe after completing it last year just south of us in Emsdale. The biggest thing he recommended was keep at it. There is a ton of stuff he still wants to do cosmetically (more paint, etc) but he's having way too much fun flying! He let me sit in it too and I'm even more convinced that I've made the right choice :)
The chance to see another completed 750 was a real good motivator!
The 701 flap repair is almost done. Some final trimming to be done, but the skin wrapped real nice and the joining patch turned out real smooth. Happy to be moving on to building my own flaps shortly and not fighting with other people's mistakes.
Ron has never been very happy with the pinched trailing edge design of the wings and flaps on the 701. The original builder (as I've been saying all along) never really paid attention and the trailing edge isn't nearly straight enough. The pinched rivets called for in the plans really add a lot of drag too.
The plans in the 750 model I'm building wraps the skins forward to the spar, making the trailing edge much cleaner both in appearance and more importantly aerodynamically. Every little bit helps!
To clean things up, we'll be adding a trailing edge strip and attach it with flush rivets. Here, we're fitting the trailing edge "cover". The first one worked real well, I'll add a picture when the one is done.
We plan on building flaps and slaps at the same time for three new 701's and my 750 and new slats for this repaired 701. This sounds like a ton of work and it is, but there are huge time savings because they are dimensionally the same, meaning we only have to set up jigs once.
I spent a couple of hours the other night bending my slat ribs on the forming block. The 750 slats are identical to the 701, so I didn't need to make my own forms for this. The only adjustment needed was one tooling hole on the tail end which is different:
So they turned out ok, but will need some clean up. Not a big deal, but not a nice as I would have liked.
Next up, finish skinning the 701 wing extension. Here is a graphic of what I have complete and ready to assemble (highlighted in blue). Lots of stuff ready to be bent still.
Thanks for reading :)
I had every intention of spending the entire day in the shop today. I'd taken the time last week to mark specific "shop days" on the calendar - days that are set aside for the shop and my build. A discussion with Brenda and our girls regarding my build led us to an agreement that these days are next to untouchable on the schedule so that I can make real progress this year. Obviously if something special comes up that can't be scheduled somewhere else my shop day can be compromised by moving it to another day, but the goal is to maintain a regular shop presence.
So, I discovered that "something special" can also includes those days when I physically can't go. Today was one of those days.
Last night at Natalie's Scout meeting, I tried to prove that I could still play volleyball like a 20 year old. A "I-used-a-could-do-that" type of thing. Needless to say I slept poorly last night and felt like I'd been run over by a Russian cargo plane today, so I missed the shop.
After some rest and feeling sorry for myself, I decided I didn't need to go over to Ron's and could at least get something done here in my own shop.
I pulled out something simple to work on - the flaperon rear ribs. These are simple flanged parts, really just smaller versions of the elevator rear ribs I made before (see my previous blog post here).
It starts with lining the forms up on the metal template. Unlike other templates, due to their size they don't have bolt holes for the forms. Just line them up and place the entire sandwich in the vice:
The soft faced dead blow hammer is used to gently form the flange over the edge of the form:
Turns out the flanges are a bit wider than the thickness of the form. With the short top-to-bottom height of these ribs, I had to devise a way to protect them when I inverted the form to bend the opposite flange. To do this, I added two blocks on each side. One of them had a small groove cut in it to make room for the opposite flange but still enough area to hold the forms:
As per the plans I need 8 left hand and 8 right hand rear ribs and I made a conscious decision to do only six right hand ones first in case I mistakenly made a right hand one when making the left hand ones. Hate to end up with extras - that would mean making replacement templates for each one I screw up. It's easy to see how this could happen, glad I thought of it ahead of time. Good trick to remember for later when I start working on all the wing ribs!
It's amazing! With a bit of attention to detail, I managed to bang out 16 flaperon ribs, all of equal dimensions and quality. Really cool.
16 complete ribs.... not bad for a day I didn't feel up to doing anything :)
I also got a new 14 tooth-per-inch blade for my band saw. Installing the new blade was challenging, but I learned on YouTube how to properly set the tension and blade guides for my model. Once I make some of the rougher cuts on the plate aluminum using the big industrial saw at Ron's shop, I can use my fine tooth band saw to make the final cuts.
I've said it before.... a little shop therapy goes a long way :)
p.s. Photo credits to my daughter Natalie.... thanks for making me look good!
One of the things that I'm really enjoying about being in the shop working on airplanes is it gives me a great way to decompress from work as a 911 dispatch supervisor.
With new technology arriving every day at work, it becomes very difficult to champion change as a team leader in the communication centre. We're all feeling a bit overwhelmed and morale at work isn't the greatest right now. I think too that we all feel we were robbed of the summer as the leaves are already changing here in our part of northern Ontario. Winters tend to be fairly sedate (we don't use the "Q" word - that's how you summon death and mayhem in emergency services) and as a result nightshifts feel longer. It's no fun going to work in the morning when it's dark and coming home when it's dark.
Going to the shop for some plane therapy helps, so that's where I headed tonight.
I made working on the 701 wing extension a priority tonight as Ron wants to get that finished up so we can concentrate on both my 750 build and finishing off his Scout. Once they are complete I'll be able to get some stick time in both while we fly off the required post inspection hours. We're aiming for spring and that should be around the time I'll need use of the workbench for my wings and fuselage.
I've been working on the wing tip extensions. We decided to extend them by 18 inches and this requires extending the wing spar caps as well. These will be extended out to the tips, giving a much stiffer extension that what the plans call for.
Here I'm using the rivet pitch guide to centre punch mark the rivet hole locations.
After marking, and using the drill press to make the holes in each of the upper and lower cap angles, I backdrilled each of the spar cap extensions through the spar web extensionm adding clecos as I went to ensure the spar web cap remained in the correct place.
Take it all apart and debur all the holes on each piece (my new tool works great for that!). Then reassemble with clecos and test fit in position at the end of the wing spar. Perfect fit, tight and level!
Fit the front side spar web extension doubler and back drill through the web. Disassemble, debur, reasemble for final fit:
I've made the spar caps match the angle of the spar tips. Really like how they look and how they will secure the tip skins:
Great progress tonight...... not bad for 3 hours of therapy :)
Those that know me also know that I tend to stew on things. It's a trait I've always had and as I grow older, I've tried turning the energy that is wasted away worrying about the little things and more towards solving the problem or fixing the mistake. It doesn't always work, but sometimes, with a little thought and time to ponder it does.
I got to thinking about the Rear Wing Root channel that I made the "oops cut" on last week. Looking over the plans, not all is lost. I'd already made the flange end longer than what the plans called for. Beefing things up in this manner is an accepted practice. This larger flange means that I still have room to correct my mistake and salvage the piece.
Here is the damage I did. You can clearly see where the cut extended beyond the relief hole:
By trimming the flange end a little bit narrow and creating a new relief hole, I eliminated the bad cut and still met the requirements for size on both. The corrected mistake is shown on the top in this picture and my second proper length "no damage beyond the relief hole" cut at the bottom:
Once I dressed and deburred the edges of the entire piece, off to the bending brake we went.
Unfortunately, I went a bit far with the lower edge. It ended up with a full 90 degrees of bend, but needed to be less than 90 to match the curvature of the wing skin.
No big deal, I just made up a jig to bend it back a bit (you can't undo bends in the brake). The key is to bend it all at once to maintain a consistent edge on the flange. You can see in the next picture that I placed the channel on the workbench and used a two-by-four and C-clamps to secure it. Ron has an excellent flanging tool just perfect for adjusting things (painted red):
Worked like a charm... my oops is no more!
Fit up seem good. Plenty of room for new rivet location and flange matches top of the rib:
Next I worked on making a new wing root attachment bracket to replace the damaged original. This required cutting thick aluminum with the band saw, a new experience for me (although I've cut wood many times on the bandsaw). It went well. The secret is to cut the piece out slightly larger, allowing room to sand/grind the piece smooth to it's final dimension:
Next up will be to make a replacement forward wing attachment bracket and the new wing root spar doubler that we discovered was missing on the original build. Luckily we have a traceable template for this:
With each repair and new fabrication I'm making, I'm getting the courage up to start bending and shaping metal for my own plane. I CAN do this!
Yesterday, I called Zenair HQ to inquire if my plans had been shipped yet. I spoke with Kaitlyn who confirmed my package left their facility via U.S.Postal Service Air Mail on Friday afternoon.
Today, using the tracking number she provided me, I logged into the USPS web-portal and discovered that as of Monday morning my package was somewhere in the bowels of the USPS International Service Center in Chicago. Further reading reveals the ISC where all outbound mail from the U.S. goes to be sorted for distribution. I also read that it can be a bit of a black hole and there are many reports of stuff going missing, never to be seen again.
Thankfully when I checked a couple of hours later and my package was showing as of Wednesday morning as being in Canada Customs. I'm normally more patient than this, but Canada Post and their postal workers union are deep into a nasty labour dispute with both sides threatening strike/lock-out action by midnight tonight! At this point I hoping my plans wouldn't end up stuck on some conveyor belt or parked truck.
Knowing that web-portals are sometimes slow to update, I took a chance and called my local Post Office (love small towns). The lady there confirmed for me that I indeed had a package awaiting pick-up!
Brenda was kind enough to drop by and pick it up for me (I was stuck at work). When I got home, it was waiting for me. To be honest, I kinda thought it would be a bigger box, but happy nonetheless it has arrived safe!
Opening the box explained a lot. The plans are curled a bit on one end to fit a standard shipping box:
A fully numbered and complete set of plan drawings and folder with builder resource information including a CD of assembly photos. Really nice stuff.
Who's a happy guy?
Today was supposed to be about cleaning.... but I also managed to get past a recent roadblock that has been keeping me awake at night!
Today's first step was to remove the oil gallery plug from each side of the engine block. I've read that on 50% of engine cores these never come out, but both of mine came out easy with a 1/4 inch extension on a ratchet:
Next, I filled a tub with hot water and Simple Green (just like the head studs a few days ago). This is the case half that didn't have any studs remaining. I wasn't sure I'd be able to fit the second case half in, but at least I can get started on this one:
While this was soaking, I decided to have another go at those two stubborn head studs. So far no amount of PB Blaster or gentle persuasion has convinced them to move even the slightest. A couple of days ago (see my last blog entry) I added a little of "home brew" mix to the studs.
I had the time today to give another try at removing them. I didn't expect 48 hours would be enough time for it to soak in the ATF and acetone "home brew" mix but WOW! They came out very easy with very little wrenching! The "home brew" worked AMAZING!
Now I've got the best chance to install all the head studs even and properly and stop worrying about two that were only partially into the block. Very cool!
By this point, I was ready to get started on cleaning the case halves. Just to prove that I'm actually doing something, Brenda took some photos of me scrubbing away some grime:
Both halves somewhat complete, a quick pressure wash to rinse off the dirty water and drying in the sun:
They look great, but as they dry I notice some spots that will require some more cleaning attention. Lots of spots that are hard to get at with a scrub sponge, I'll have another go with a toothbrush and maybe the Dremel tool and a 3M wheel. I also see a bunch of casting flash from the factory that needs to be removed to improve oil flow. It's surprising how little GM did in this regard.
I have some rusty spots that will also require some attention. I'll do some research on the best way to address this.
Good progress today, especially the last two head studs. Moving on!
Completed a milestone today with inventory. All parts catalogued, numbered and tagged using the numbering system from the conversion manual. Similar items placed in totes, totes numbered accordingly. All stacked and awaiting cleaning, measuring and disposition:
From top to bottom:
I've also got a bin full of associated hardware bolt, nuts, old gaskets etc.:
All of these were loose items in a pail and are typically filthy and rusty as to be expected from a 50 year old engine. They will need to be cleaned and assessed before making a decision on keep or toss.
Next step will be to build a parts cleaner.... stay tuned :)
What used to look like this:
Now looks much, MUCH better:
The biggest change is floor space. I'm no longer tripping over stuff to work on other stuff. Most of that is from better organization and better work surfaces. And a personal commitment to put stuff back where it belongs.... HA!
It's certainly not perfect. I still have some decisions to make on some of the smaller items and some stuff to get rid of (bonfire anyone?) I doubt it ever will be perfect, but it's a darn sight better than what it was!
On another note, I picked up a digital calliper on sale at Home Hardware during their no tax sale this weekend:
Like the dial indicator I bought a couple of weeks ago, this will be an invaluable tool to measure the engine components as I pull apart the core engine.
Off tomorrow to look at 2 cores that should be acceptable for conversion! Now I have space to work. Very motivating :)
Time until takeoff
Husband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane.