This is not cheap, appears as it would save hunreds of hours high-performance-tape

[hogheadv2]

http://www.lamatek.com/catalogs/hvac/high-performance-tape.shtml

77 to over 100 pounds per sq inch tension, 49 to 79 lb sq in. Dynamic shear, static shear 65-97 lb sq in.
Put a panel in place and it's held. Half the rivets and cleos to deal with. A few to choose from, from what I see plan on $270 to $320 a box of 10 rolls. But if time is money, sealing joints and preventing chaffing and rivets getting loose this may be a fantastic investment. window seals, air ducts, So many uses come to mind. This company also supplies bump stops foam tapes , speaker feet, 2 sided foam tape for electronic installs.

Hoghead.:cool:

[Matt Gonitzke]

Surely you can't be suggesting replacing rivets on an aircraft with that, right?

[hogheadv2]

My plan may reduce rivets by 1/3. I am looking at once the panel is fit. No cleco's or just a very few would be needed. With careful one time placement. Pattern work around the panel / part [ drill, de-burr, rivet ] with a water proof bond.

*** This is not unlike the method used for aluminum boats, here in the North 40 year old boats beaten by the rivers and left out all winter, wipe out the leaves and serve to fish in the spring is a daily sight. BTW my 14 ft has 53" beam and weights 142lbs with three aluminum bench seats.

That kind of durability would comfort me in the sky.

[Matt Gonitzke]

This isn't a boat, it's an airplane. The stresses experienced by an aluminum boat are far less than those that an aircraft must be designed for. You have no hard data for the durability of the adhesive bond as it ages, nor do you have any idea how conservative or unconservative the data from their website is.

If you have a riveted joint in 0.025" 2024-T3 sheet, 1/8" AD rivets at 4D spacing, and you omit every 3rd rivet and put a 2" wide piece of tape over the top of the lap joint, you have a joint with at least 25% LESS strength than the riveted joint, and this is assuming that a) you are using the tape with the highest adhesive shear strength and b) the shear capability of the adhesive carrier material is greater than the adhesive itself, the latter of which is probably not a good assumption. If the material thickness is greater than 0.025", the strength reduction is even greater. You'll probably have a weight increase, too, as there's no way that tape is going to be lighter than 1/3 of the rivets in the joint.

Duct tape is for duct work. Not airplanes...

[jjhoneck]

I think Hoghead is talking about using this method to achieve an improved look for his panel, not for anything structural.

[brian_thomas]

> Duct tape is for duct work. Not airplanes...

3408

[Matt Gonitzke]

Brian, I figured somebody would dig up those pictures. The OP doesn't have a fabric-covered bushplane in Alaska requiring a one-time emergency repair. Totally different situation.

jjhoneck-

Perhaps he'll clarify for us, but when someone starts quoting strength data and says things like "that kind of durability would comfort me in the sky" it sure sounds like he's intending to use it for structural applications. Even if not, I'd hate to have somebody stumble across this thread and think it's ok to do something like that on a structural joint.

[hogheadv2]

This is a 2 sided tape, to join the parts and make a waterproof bond. The information page states it is intended to replace mechanical fasteners such as rivets, screws, spot welds....
***Sharing a useful construction method and unless it come from an aircraft manufacture every body here shits on it.
Apparently Experimental should be removed from the forum listings.... "Where can I get stuff for free?" "That will never work" is more fitting. for the Free thinkers here who are afraid to learn the math.

SilverTape® offers superior high bond strength and can replace mechanical fasteners like rivets, screws, spot welds and liquid adhesives on a variety of substrates. - See more at: http://www.lamatek.com/catalogs/hvac/high-performance-tape.shtml#sthash.odAcExoF.dpuf


http://www.lamatek.com/catalogs/hvac/tape-vs-mechanical-fasteners.shtml

[Frank Giger]

I guess it would all come down to application.

Heck, I've got some aluminum duct tape in my airplane build! I used it over the boxes I put behind the aileron hinges for a more robust seal to help stave off some drag.

Super industrial tape to help secure a panel? Depends on the panel. On my little Nieuport, the panel is a tiny thing of sheet aluminum that isn't really structural. Don't know on weight savings, though - one would have to weigh the tape versus the same in rivets; my guess it would be a wash.

Would I use tape to secure my cowling? Um, no. Nor would I use it instead of rivets for holding the hinges for my access panels.

Then again, who knows? Think of what the conversations were like when some joker said that the best way to attach fabric to an airframe was with a super new kind of glue!

[Matt Gonitzke]

This is a 2 sided tape, to join the parts and make a waterproof bond. The information page states it is intended to replace mechanical fasteners such as rivets, screws, spot welds....
***Sharing a useful construction method and unless it come from an aircraft manufacture every body here shits on it.
Apparently Experimental should be removed from the forum listings.... "Where can I get stuff for free?" "That will never work" is more fitting. for the Free thinkers here who are afraid to learn the math.

SilverTape® offers superior high bond strength and can replace mechanical fasteners like rivets, screws, spot welds and liquid adhesives on a variety of substrates. - See more at: http://www.lamatek.com/catalogs/hvac/high-performance-tape.shtml#sthash.odAcExoF.dpuf


http://www.lamatek.com/catalogs/hvac/tape-vs-mechanical-fasteners.shtml

You didn't even read my post. I ran the numbers and showed you why it wouldn't work. Sure, it can replace mechanical fasteners in things like ductwork. Just because their information page says something doesn't mean it's universally applicable to everything in existence...

[I_FLY_LOW]

This is a 2 sided tape, to join the parts and make a waterproof bond. The information page states it is intended to replace mechanical fasteners such as rivets, screws, spot welds....
***Sharing a useful construction method and unless it come from an aircraft manufacture every body here shits on it.
Apparently Experimental should be removed from the forum listings.... "Where can I get stuff for free?" "That will never work" is more fitting. for the Free thinkers here who are afraid to learn the math.

SilverTape® offers superior high bond strength and can replace mechanical fasteners like rivets, screws, spot welds and liquid adhesives on a variety of substrates. - See more at: http://www.lamatek.com/catalogs/hvac/high-performance-tape.shtml#sthash.odAcExoF.dpuf


http://www.lamatek.com/catalogs/hvac/tape-vs-mechanical-fasteners.shtml

Relax.. You should be golden..
As long as you don't use latex paint, or run car gas...

[1600vw]

All tape I have ever dealt with after time will fall apart. Leave it out in the sub zero and its even worse. Hangar conditions would ruin any tape I have seen.

[Matt Gonitzke]

More in-depth response than I had time for at 5:30am...

I guess I'll continue to be blunt; this is not a 'useful [aircraft] construction method'. Period. It will be both heavier and weaker than the riveted joint you are trying to 'improve'. Even at 0.025" thickness, the thinnest tape is going to make the riveted joint worse. Hogheadv2, once you tape the panels together, how will you deburr the holes after you drill them? The thickness of the tape creates a gap between the two sheets you are trying to join, which will cause the rivet to bulge between the sheets when driven, which is not acceptable because it further reduces the strength of the joint. Nothing is guaranteeing that the materials in your taped joint would allow the tape to load up to its rated strength before failing. There are FAR too many unknowns here to make this worth pursuing, not to mention the fact that it takes 10 minutes worth of calculations to determine that there is both an increase in weight and reduction in strength.

Riveted aluminum aircraft have existed for more than 75 years, and the method of construction understood better than any other aircraft construction method. If you find the need to worry about 'rivets getting loose' on a properly-designed aircraft, then your riveting skills need improvement. Experimentation is great, but there is no point to it when you end up with an inferior, heavier joint in the end. No need to take it personally, either. Take this as an opportunity to learn something and move on...:)

[Aaron Novak]

Relax.. You should be golden..
As long as you don't use latex paint, or run car gas...

You forgot " or use a harley engine ".........

[Frank Giger]

And please take into account that Matt isn't crapping on you; he's pointing out the weaknesses in using tape instead of rivets.

Caution and prudent risks are the watchwords of experimentation, particularly when one's life literally depends on making the right choices.

Heck, on my build I had to make a modification to fix some bad measurements so that the lower wing carry-throughs would fit. To say I did a poor job would be accurate - it wasn't the approach but the workmanship that had the potential for material failure down the road. The response from the group at the photographs was vehement on the fact that I had to remove the tubing, replace it, and make new gussets in the extreme.

It wasn't personal in the respect that they were critical of what I had done; it was extremely personal in that they didn't want to talk about me in the past tense.

That said, any part of an aircraft placed under routine stresses that a rivet would naturally become loose shouldn't be riveted in the first place; that's what they make bolts for!

[Victor Bravo]

Bonding aluminum aircraft structures, using any kind of glue, or any kind of double-sided tape, is definitely not something that you should be thinking about.

The ONLY examples of aluminum bonding on aircraft structures that have really worked, ever, are done in very complex machines owned by very large aerospace companies. No homebuilder can afford it, and nobody other than big aerospace can do this reliably and safely.

Small GA airplanes built in professional factories with special equipment have had a checkered result. The Grumman Yankee/Cheetah/Tiger are mostly OK using this method, but even they had well known problems and failures with glue, which have failed to some degree in several cases.

Homebuilt airplanes using bonded aluminum structure have a HORRIBLE record. The Monnett Moni and Monerai gliders have suffered more than one fatality because of bonding problems done by homebuilders. They manufacture only riveted airplanes now. The Schreder HP series of homebuilt sailplanes have had numerous failures but fortunately few or no fatalities because of this issue... but many of them have serious bonding problems.

The CriCri has had the fewest of the problems, but is still a risky proposition compared to riveting.

Now the aircraft bonding on all of the above was done with special aerospace epoxy adhesives, not a roll of any commercial carpet tape. The Hysol adhesive used in aerospace was tested to aerospace standards, and represents a known value.

To think that any industrial or "Home Depot" level tape product could be safe over time in aircraft construction is ludicrous. Remember the "Gorilla Glue" at Home Depot, where the package SAYS it is the world's strongest glue??? Airplane people did tests on it, and found that over time it loses a large part of its strength. So it might be fantastic the first few months or years, but then it gets weaker.

The double stick tape MAY be a fantastic adhesive... but it has to have independent field testing and data collection BEFORE you start using it as a structural bond!

[I_FLY_LOW]

What about the bonding agent used in the sheetmetal on automobiles?
That stuff holds up to a LOT of constant abuse, every single day.
Hot or cold, rain or shine.
Even when wrecked, it still manages to hold together.
Do they make an aviation oriented version of that?

[JoeB]

What about the bonding agent used in the sheetmetal on automobiles?
That stuff holds up to a LOT of constant abuse, every single day.
Hot or cold, rain or shine.
Even when wrecked, it still manages to hold together.
Do they make an aviation oriented version of that?

In my experience, adhesives used in structural automotive applications also use screws or rivets.
The adhesive bond is broken (during repairs) using a heat gun or propane torch (low temps).
The application of the expensive primer and adhesive repairs proper, and sometimes challenging, procedures.
I really don't think it would save construction time outside of an assembly line and it certainly would not be more economical, weight savings if any is marginal.

[tonycondon]

The Schreder HP-18 was a popular all metal homebuilt glider that had bonded wing skins...


Bonding aluminum aircraft structures, using any kind of glue, or any kind of double-sided tape, is definitely not something that you should be thinking about.

The ONLY examples of aluminum bonding on aircraft structures that have really worked, ever, are done in very complex machines owned by very large aerospace companies. No homebuilder can afford it, and nobody other than big aerospace can do this reliably and safely.

Small GA airplanes built in professional factories with special equipment have had a checkered result. The Grumman Yankee/Cheetah/Tiger are mostly OK using this method, but even they had well known problems and failures with glue, which have failed to some degree in several cases.

Homebuilt airplanes using bonded aluminum structure have a HORRIBLE record. The Monnett Moni and Monerai gliders have suffered more than one fatality because of bonding problems done by homebuilders. They manufacture only riveted airplanes now. The Schreder HP series of homebuilt sailplanes have had numerous failures but fortunately few or no fatalities because of this issue... but many of them have serious bonding problems.

The CriCri has had the fewest of the problems, but is still a risky proposition compared to riveting.

Now the aircraft bonding on all of the above was done with special aerospace epoxy adhesives, not a roll of any commercial carpet tape. The Hysol adhesive used in aerospace was tested to aerospace standards, and represents a known value.

To think that any industrial or "Home Depot" level tape product could be safe over time in aircraft construction is ludicrous. Remember the "Gorilla Glue" at Home Depot, where the package SAYS it is the world's strongest glue??? Airplane people did tests on it, and found that over time it loses a large part of its strength. So it might be fantastic the first few months or years, but then it gets weaker.

The double stick tape MAY be a fantastic adhesive... but it has to have independent field testing and data collection BEFORE you start using it as a structural bond!

[jjhoneck]

Glues CAN work for certain things.

Example: I attached my gear-to-fuselage fairings to my RV-8A with RTV. No screws, no rivets.

Of course, that's a nonstructural, 6-ounce, aerodynamic fairing -- not a wing skin.
:)

[rwanttaja]

Glues CAN work for certain things.


News to me.

Ron Wanttaja
1981 Bowers Fly Baby

[Victor Bravo]

The Schreder HP-18 was a popular all metal homebuilt glider that had bonded wing skins...

I mentioned the HP's in my post. I owned an HP-18 project for a short time, and the reason it was a project was because the skins had de-bonded from the ribs, and it was finally sold because of this very reason.

I have a friend who is a chemist and aircraft builder. He informed me that there IS a way to do structural bonding of aluminum. You have to use a SPECIFIC, PARTICULAR formulation of chemical treatment, which changes the chemical composition of the metal surface, which makes a surface that will bond to epoxy. But this is NOT off-the-shelf Alodine or Anodize.

And it is still not a 100% strength bond like wood and Resorcinol.

[jjhoneck]

News to me.

Ron Wanttaja
1981 Bowers Fly Baby

Heh. Just be sure not to post about it on certificated aircraft forums! You'll never hear the end of it.
:)

[jjhoneck]

I mentioned the HP's in my post. I owned an HP-18 project for a short time, and the reason it was a project was because the skins had de-bonded from the ribs, and it was finally sold because of this very reason.

I have a friend who is a chemist and aircraft builder. He informed me that there IS a way to do structural bonding of aluminum. You have to use a SPECIFIC, PARTICULAR formulation of chemical treatment, which changes the chemical composition of the metal surface, which makes a surface that will bond to epoxy. But this is NOT off-the-shelf Alodine or Anodize.

And it is still not a 100% strength bond like wood and Resorcinol.

Doesn't one of the current 4-place Bede kitplanes have the skins wrapped around and glued to the ribs? I think they are only physically attached at the trailing edge.

[Jim Hann]

Doesn't one of the current 4-place Bede kitplanes have the skins wrapped around and glued to the ribs? I think they are only physically attached at the trailing edge.
BD-4C, we have one going together in our Chapter. ProSeal I believe!

[Greg Wilson]

"if time is money, sealing joints and preventing chaffing and rivets getting loose this may be a fantastic investment. window seals, air ducts, So many uses come to mind." hoghead does not say to replace rivets in all applications or to even replace all rivets only one-third of them perhaps. The statement/question is one of possible time savings and other (sealing) benefits. There is NO structural reason for "mold-less" composite but it was great for Rutan ( He has stated the reason was simply time savings). Loss of strength is not a problem IF the joint still meets the design need. To those who insist that every thing must be "aircraft" quality by design decree, by a type certificated aircraft and pay an A&P to maintain it for you, don't say everything must be "approved" T.C.,PMA, TSO,etc. and then bitch about the cost as the reason to be experimental. Experimental-AB is to experiment,safely but experiment none the less. I have worked on "bonded" aircraft Grumman American and Lear Jets, yes they have problems but the "glue" still works. The Grumman has an AD requiring #3 rivets to be installed at a wide spacing to serve as a "rip-stop" on the trailing edge it does not replace the bonding for structural strength. Greg Wilson A&P since 1982

[WeaverJ3Cub]

Am I seriously reading someone advocating using tape to replace rivets and structural fasteners??? *facepalm

To the OP....for one, airplanes flex in ways that boats don't, so that really isn't a valid comparison. Just look at pictures of the Reno racer Czech Mate's wing flexing under the g load. Your average RV is subject to nowhere near that load for sure, but I guarantee you that stuff is still moving in ways you don't realize.

[hogheadv2]

Am I seriously reading someone advocating using tape to replace rivets and structural fasteners??? *facepalm

To the OP....for one, airplanes flex in ways that boats don't, so that really isn't a valid comparison. Just look at pictures of the Reno racer Czech Mate's wing flexing under the g load. Your average RV is subject to nowhere near that load for sure, but I guarantee you that stuff is still moving in ways you don't realize.

Really, your building a Reno Racer! Keep your eyes covered with the facepalm, while your at it plug your ears.
This may keep you from taking a comment intended for people who have sense to use materials in a safe and responsible manner. I'm really sure most of us are not looking past 9+ G's. If they are, this forum is not the place to find that kind of performance.

[Aaron Novak]

Really, your building a Reno Racer! Keep your eyes covered with the facepalm, while your at it plug your ears.
This may keep you from taking a comment intended for people who have sense to use materials in a safe and responsible manner. I'm really sure most of us are not looking past 9+ G's. If they are, this forum is not the place to find that kind of performance.

Why not? To me a forum is a place for those that know more, to share with those that know less, hence education and the swapping of ideas. The internet is already full of forums with a group of people that know little, patting each other on the back and telling each other how great they are. Lets not have another one please. When someone presents something that to the trained eye seems like a bad idea, they should be called out on it, and given reasons why its a bad idea. There is nothing wrong with tearing apart a bad idea, thats what engineering is, what was done here, and what homebuilding is about.

[Matt Gonitzke]

This may keep you from taking a comment intended for people who have sense to use materials in a safe and responsible manner.

How ironic. If you're so knowledgeable about aircraft structural design and analysis, how come you can't refute any of the flaws that multiple people have pointed out in your idea?

[CraigCantwell]

If you are set on using this stuff, I would suggest that you spend the bucks and have a qualified design engineer do a sample joint analsys and comparison for you. Placing a compressable foam based tape, that is equal to or thicker than your two pieces of sheet metal in the middle of a structural joint, simply screams poor design for aircraft.

If there was a product like this that would work well in the aerospace industry, we would be using it commercially. Also, look at the design guys that have hundreds or thousands of their desings built or under construction...you won't see any of them using anything like this in a structural application.

You might want to do a cost analysis on using it too. Not only the tape cost, but the chemicals needed to prep the surfaces for bonding.

Lastly, I can tell you for a fact that it will not be a time saver at all. The necessary prep work, the extra care in riveting and the fact that you will need assistance in placing skins of any large size will kill your progress. Also, should you make any mistake in placement or need to remove the skin, you run a high risk of damaging the skin or understructure during the removal. Once you get the hang of riveting, you can shoot hundred of rivets in less time than messing with this tape.

A couple of things I noted from their website....They give no performance information at low temps...Also, they tout this stuff as a shock absorbing material....just what you want (NOT...) in a structural joint for something you are wanting to be as failure free as possible. They also say that it is solvent resistant, but give no ratings as to what they have tested it against. Are you willing to bet your life that it wasn't attacked by the paint you used, that little bit of gasloine you spilled on the joint or by the little bit of oil that is runing down the crack? You do know that oil, gas, lacquer thinner, acetone and MEK all attack acrylics?

Food for your thought.......