Your multitasking priorities approach to advancing the completion of the two planes is very sensible. I really enjoy your videos and they are very useful for much more than building airplanes.
Hello Mark, many thanks for the very interesting insights into the restoration of your Pitts! Your surname also piqued my interest because a small settlement near my home town is called “Penzenstadl”.
I just discovered this channel about a year after it was posted..It was recommended to me on my Sparcraft wings to replace the nails that hold the aluminum leading edges on with tiny wood screws instead.When you start flying hard acro with it the screws won’t come loose like nails do. that’s one way to tell how hard an S1 has been flown,by “Nail Pops”
SuperFil is the absolute greatest lightweigh epoxy filler ever created by man. It sands smooth as easy as butter, and feathers out like nothing I've ever used before. It is worth it's weight in gold as far as I'm concerned!!
i bought a pitts s1 10 years ago flew it 2 times then did what it is meant for. i hung it in my hanger as a big model airplane im sure it still runs and is still flyable since it was recovered 3 months before i bought it. paid 10 grand for it from a estate sale. engine if i rmeember correctly has only 6 hours on it. but i pickeled it drained oil and gas and hung it up in the rafters of the hanger. pretty sucker but they are all painted the same. red and white with a sunburst. makes the best hanger toy still looks nice i put on like 15 coatss of carnuba wx i winch it down ever 6 months and dust it off lol i do have the annual done once a year..think i missed this year. found another one cheap also will buy it and hang it on the wall of the hanger they do look cool hanging around lol
Nice on the superfill! Bondo only belongs on cars, not airplanes! I use hotel keycards for epoxy also! I believe the fabric tester you are talking about is the “Maule tester” and the poly fiber manual says that test is NOT to be used on poly fiber coverings.
You’re testing the bottom of the wing which will test to a higher test number than the top. Maule testing is typically done to the top of the wing which due to exposure, uv, etc will reveal the worse fabric and its number
Mark, do a search on Sparcraft wings. They can have issues if flown hard. I would most definitely use a boroscope inside the leading edge to be sure that the nose ribs are intact and secure. I recently saw one at a contest that the nose ribs had folded over and allowed the aluminum to flatten in the airflow. There are fixes recommended if the airplane will be flown in competition. Best, Mark Too
Aren’t the Sparcraft wings an upgrade from a different company? This is an E model (kit) so I wouldn’t think these are Sparcraft wings. Unless that’s what they used in the kit? Either way, prob still a good idea to put my scope in there and take a look.
@@KitplaneEnthusiast The story goes that a set of wing plans went home in somebodies lunch box and the Sparcraft wing was born. The vertical webs/intersections have not proven to be adequate for Advanced/Unlimited type aerobatics. The proposed fix is to glue a 1/4” piece of spruce on both sides of the vertical to support them in compression. There is a large quantity of info on the BPF and in the Technical Tips manuals from IAC.
Sparcraft wings are most definitely NOT an upgrade. They were considerably more economical to build. I can tell you from personal experience they are not as strong , especially when being flown hard as truss type factory ribs. There was an “improvement” done to later Sparcraft wings involving a capstrip on the ribs that strengthened them considerably. As was mentioned, do some research.
When i had my shop, we used the Maule tester. If I remember we set it to 55 pounds. But, the instructions were to remove the paint in the area to be tested. We would use MEK or acetone and remove maybe a quarter sized area. If it passed we would re finish the area.
Great to see the condition of the airframe is so fine. Two things, Maybe avoid exposure to MEK for removal of the adhesive and go with something like Goo-Gone. The fabric was in excellent condition. That failure by fiber separation is by design, retaining maximum integrity. Had the fabric degraded, the fibers would fracture.
Thanks for the video! Just a couple comments I'll through out there... I see nylon zip ties on the cross bracing in the wing. I've seen them get brittle over time. Many plastics get brittle after decades. I'd replace them with black ones while the skin is off. I like black ones because they hold up well against sun light (UV). Though not an issue inside the wing, you never know what else you might use them for. Are the bearings in the bell-cranks sealed type? If not, grease may have more staying power than spray oil type lube. A couple things I've heard over the years about lubes... If it spins, oil it. If it slides, grease it. Oil is better in dusty environments (oil gets reapplied and flushes out the dirt). Grease is better in clean environments. That Pitts looks to be in great shape! Thanks again.
@@KitplaneEnthusiast I just had this discussion this morning with a friend who rebuilt an RV-6. Basically he did just what you are doing. He learned from the FSDO and DAR that had he declared the airplane salvage and turned in the existing AW cert. He could then have reapplied to the FAA as a new/rebuilt airplane with a new tail number, (I guess you could probably reregister the original tail number). Then he would be able to get the Repairman's Certificate based on it being a substantially rebuilt plane. It is worth looking into.
As it turns out, if you are carrying a sheet of aluminum under your arm and bend over as you go under a high wing, the back corner of the sheet will come up and slice through the fabric like there is nothing there. Guess how I know...
G,day Mark from Sydney Australia. The integrity of the fabric on that Pitts is fairly good. Being thirty years old, is it Dacron; or some polyester? 🌏🇦🇺
I hate those metal wing wrap leading edges. Pitts still does that at the factory (Aviat). Lots of issues like denting and nails protruding loose over time. Glued wood wrap is the way to go which makes the wing stiffer as a whole and so much stronger. Metal does not add strength. Metal is an old technique.
Why are you damaging a perfectly good airplane? UA-cam likes? That airplane doesn’t even have 100 hours since it was last restored and you’re cutting the fabric off? Then you get bored and try to sell it to somebody who actually values the airplane. Shame
Your multitasking priorities approach to advancing the completion of the two planes is very sensible. I really enjoy your videos and they are very useful for much more than building airplanes.
Well done Mark, thank you!
Very interesting for sure - many thanks
Hello Mark, many thanks for the very interesting insights into the restoration of your Pitts! Your surname also piqued my interest because a small settlement near my home town is called “Penzenstadl”.
Mark, thanks again for another interesting video. Lots of work to occupy your time.
I just discovered this channel about a year after it was posted..It was recommended to me on my Sparcraft wings to replace the nails that hold the aluminum leading edges on with tiny wood screws instead.When you start flying hard acro with it the screws won’t come loose like nails do. that’s one way to tell how hard an S1 has been flown,by “Nail Pops”
You had to push harder than I thought. That is some tough covering.
SuperFil is the absolute greatest lightweigh epoxy filler ever created by man. It sands smooth as easy as butter, and feathers out like nothing I've ever used before. It is worth it's weight in gold as far as I'm concerned!!
It really is good stuff. I’ve used it on every plane I’ve built. Ever notice how the white part smells like dead fish? Lol. Man it stinks!
i bought a pitts s1 10 years ago flew it 2 times then did what it is meant for. i hung it in my hanger as a big model airplane im sure it still runs and is still flyable since it was recovered 3 months before i bought it. paid 10 grand for it from a estate sale. engine if i rmeember correctly has only 6 hours on it. but i pickeled it drained oil and gas and hung it up in the rafters of the hanger. pretty sucker but they are all painted the same. red and white with a sunburst. makes the best hanger toy still looks nice i put on like 15 coatss of carnuba wx i winch it down ever 6 months and dust it off lol i do have the annual done once a year..think i missed this year. found another one cheap also will buy it and hang it on the wall of the hanger they do look cool hanging around lol
Bravo.thenks
Your punch test was done on the bottom, try the top where the sun gets to it!
Nice on the superfill! Bondo only belongs on cars, not airplanes! I use hotel keycards for epoxy also! I believe the fabric tester you are talking about is the “Maule tester” and the poly fiber manual says that test is NOT to be used on poly fiber coverings.
You’re testing the bottom of the wing which will test to a higher test number than the top. Maule testing is typically done to the top of the wing which due to exposure, uv, etc will reveal the worse fabric and its number
Mark, do a search on Sparcraft wings. They can have issues if flown hard. I would most definitely use a boroscope inside the leading edge to be sure that the nose ribs are intact and secure. I recently saw one at a contest that the nose ribs had folded over and allowed the aluminum to flatten in the airflow. There are fixes recommended if the airplane will be flown in competition.
Best, Mark Too
Aren’t the Sparcraft wings an upgrade from a different company? This is an E model (kit) so I wouldn’t think these are Sparcraft wings. Unless that’s what they used in the kit? Either way, prob still a good idea to put my scope in there and take a look.
@@KitplaneEnthusiast
The story goes that a set of wing plans went home in somebodies lunch box and the Sparcraft wing was born.
The vertical webs/intersections have not proven to be adequate for Advanced/Unlimited type aerobatics.
The proposed fix is to glue a 1/4” piece of spruce on both sides of the vertical to support them in compression.
There is a large quantity of info on the BPF and in the Technical Tips manuals from IAC.
Sparcraft wings are most definitely NOT an upgrade. They were considerably more economical to build. I can tell you from personal experience they are not as strong , especially when being flown hard as truss type factory ribs. There was an “improvement” done to later Sparcraft wings involving a capstrip on the ribs that strengthened them considerably. As was mentioned, do some research.
When i had my shop, we used the Maule tester. If I remember we set it to 55 pounds. But, the instructions were to remove the paint in the area to be tested. We would use MEK or acetone and remove maybe a quarter sized area. If it passed we would re finish the area.
Thanks for saving this one. So sad to see them hanging from ceilings or hidden under layers of dust in a dark corner of the hangar.
Great to see the condition of the airframe is so fine.
Two things,
Maybe avoid exposure to MEK for removal of the adhesive and go with something like Goo-Gone.
The fabric was in excellent condition. That failure by fiber separation is by design, retaining maximum integrity. Had the fabric degraded, the fibers would fracture.
They were called Maule Tester..got 4 of them
Thanks for the video!
Just a couple comments I'll through out there...
I see nylon zip ties on the cross bracing in the wing. I've seen them get brittle over time. Many plastics get brittle after decades. I'd replace them with black ones while the skin is off. I like black ones because they hold up well against sun light (UV). Though not an issue inside the wing, you never know what else you might use them for.
Are the bearings in the bell-cranks sealed type? If not, grease may have more staying power than spray oil type lube. A couple things I've heard over the years about lubes...
If it spins, oil it. If it slides, grease it.
Oil is better in dusty environments (oil gets reapplied and flushes out the dirt). Grease is better in clean environments.
That Pitts looks to be in great shape!
Thanks again.
Good idea to replace the zip ties. They do get brittle over time so it certainly won't hurt to replace them.
Wished u gave a little more tooth to the shallows of ur putty fix… good job! Great Airplane.
Where can I get one.😎
Keep the updates coming!
The punch tester is only for certain fabric and finishes. Not, for example, used on ceconite with Poly fiber. They have their own tests.
enjoyed
Are those SparCraft wings? I rebuilt a set of wings for a friends S1 in the late 90's and it had Sparcraft wings and they looked the same as yours.
Are you going to declare the Pitts as Salvage? That way you can be the new builder/repairman for the airplane.
I've never heard of doing that. Explain how that would work. I'd love to find a way to get the Repairman's Cert!
@@KitplaneEnthusiast I just had this discussion this morning with a friend who rebuilt an RV-6. Basically he did just what you are doing. He learned from the FSDO and DAR that had he declared the airplane salvage and turned in the existing AW cert. He could then have reapplied to the FAA as a new/rebuilt airplane with a new tail number, (I guess you could probably reregister the original tail number). Then he would be able to get the Repairman's Certificate based on it being a substantially rebuilt plane. It is worth looking into.
As it turns out, if you are carrying a sheet of aluminum under your arm and bend over as you go under a high wing, the back corner of the sheet will come up and slice through the fabric like there is nothing there.
Guess how I know...
Is your Pitts wings a Sparcraft manufactured kit? I noticed the plywood ribs instead of stitca
You are at an airpark in Michigan??? 🥶
G,day Mark from Sydney Australia.
The integrity of the fabric on that Pitts is fairly good. Being thirty years old, is it Dacron;
or some polyester?
🌏🇦🇺
WD-40 is helpful to remove tape residue without harming most surfaces.
Would poking the top side of the wing produce different results (possibly more exposure to sunlight)?
Probably not. This airplane was hangared it's whole life.
Quicksilver makes a tester thats affordable.. tho i think the point is too sharp but what do i know. My plane is in pieces
I hate those metal wing wrap leading edges. Pitts still does that at the factory (Aviat). Lots of issues like denting and nails protruding loose over time. Glued wood wrap is the way to go which makes the wing stiffer as a whole and so much stronger. Metal does not add strength. Metal is an old technique.
No rib stitching? Interesting.
Everything was rib stitched. I cut the cord before pulling off the fabric.
No more excuses.....this plane was ready to fly ......
Fear?
How’s it feel to be the most ignorant person on the internet?
Why are you damaging a perfectly good airplane? UA-cam likes? That airplane doesn’t even have 100 hours since it was last restored and you’re cutting the fabric off? Then you get bored and try to sell it to somebody who actually values the airplane. Shame
Your ignorance and lack of knowledge shines brightly.