Glue the Ungluable

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dhbarr

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Form follows function. It's an application where glue doesn't work, an application where we are trying to "glue the ungluable"

Hmm, seems like I remember a thread like that on TRF?

It's a real example showing the fallacy of this statement:
So if I glue two pieces of tissue paper together with school glue, then tug on them, the glue failed?
 

lakeroadster

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By that logic, fingers are not gluable, because gluing one's fingers to things (e.g. with CA) is a bad idea. And cars capable of driving at 80 mph on a good quality highway are incapable of going 80 on a residential street.

Perhaps the thread title should be "Bonding the Unbondable". I think it was abundantly clear from the OP that the subject is bonding, not suitability thereof.
You're just being argumentative, as you are well aware that different adhesives & materials are used for HP versus LP
 

lakeroadster

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So if I glue two pieces of tissue paper together with school glue, then tug on them, the glue failed?
No, the tissue failed. But what does that have to do with the topic at hand?

Here's the string of threads...
What glue would I use to attach a spring steel engine hook to a cardboard motor tube?​
You replied:
One of the more flexible CAs, but you'll still need to back it up with the over ring.​
I replied
Because the glue won't hold... that's kind of the point... Saying we can glue anything... may be true... but if it doesn't work.. what's the point?​
In the case you pointed out... the ring is taking the stress of the spring steel being bent.

So why are you posting about tissue paper?
 

jqavins

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Because the thread title, which only partly represents the actual thread subject, is a thing that allegedly can't be glued, not things that should or shouldn't be. Tissue can be glued, and when the tissues tear it is because the glue bond did, in fact, hold, proving the statement that tissue can be glued. Spring steel engine hooks can be glued to cardboard MMTs, and when the cardboard tears it is because the glue bond did, in fact, hold, proving the statement that these two materials can be glued.

The thread subject in full (beyond the few words of the title) is glue that will bond to polypropylene. The right question is: why were you posting about gluing a spring steel engine hook to a cardboard MMT in a thread about gluing to polypropylene (or other perhaps materials that are believed to be ungluable).

Try this experiment, in your head or with real materials. Take six strips of spring steel; some epoxy, polyurethane glue, and CA glue; and pieces of cardboard and tupperware (polyethylene, not polypropylene, but close enough.) Place one drop of each glue on each substrate then press the steel strips into the drops. Wait for full cure. then:
  • Pick up and shake the two substrates; see which, if any, of the steel strips fall off.
  • Tug very lightly on the remaining strips; see which, if any, pull off.
  • Pull harder on each remaining strip; see which, if any, glues remain on the substrates, which come off with the steel, and which take some substrate material along with them.
After considering the results, tell us again that you can't glue spring steel to cardboard.
 
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OverTheTop

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I have Loctite 401 (used frequently) and the 770 primer. I remember using it years ago to glue something difficult and having success with the combination. I still would not trust it in peel.
 

lakeroadster

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The thread subject in full (beyond the few words of the title) is glue that will bond to polypropylene. The right question is: why were you posting about gluing a spring steel engine hook to a cardboard MMT in a thread about gluing to polypropylene (or other perhaps materials that are believed to be ungluable).
I guess I'm guilty of not reading all the posts when I just jumped in?

Thread drift is a thing Joe. (See Post #8) Maybe you could ask a moderator to change the thread title, since it seems to be a touchy subject.

After considering the results, tell us again that you can't glue spring steel to cardboard.
Not cardboard, a cardboard motor mount tube.

What glue would I use to attach a spring steel engine hook to a cardboard motor tube?
I didn't think I'd have to explain that I'd want is to be successfull, and not rip the motor mount tube. Ruining the motor tube would be a non-starter for me.
 
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lakeroadster

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Or the first one. Or looking up what "can't" means.
You responded to the same post that I did initially Joe. You're the OP and you too were off topic.

I wonder what bonds well to ice. I mean, if it's kept cold and solid, with a smooth flat face, I'm sure there is something that would work. But what? It has to be something which can be applied and will cure (or dry) while cold. Hmmm. Construction adhesive for building igloos.
 

Ez2cDave

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I guess I should have caveated that with nothing we use in rocketry is unglueable..
Nothing ? How about PTFE ( Teflon ), Nylon, and that "milk jug" plastic that was used on ACE nosecones ?

Dave F.
 

DarthMuffin

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I looked up that stuff and cheapest I could find was about $60 a tube!

I might try some of this instead for PP.
FYI, I got to try the above linked adhesive last weekend on a PP nosecone to a PP-filament printed avbay. Worked great! Although it's 2 part stuff it's weird and not like an epoxy. Seemed to expand slightly like urethane glue and also dried out and left crystals where I tried a fillet.
 

Halvey

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Looked into getting some CA plastic primer for a foamie EDF that was on the table. Unable to get it at that time. I ended up using The Right Stuff to glue smooth plastics and nylons together, after a bit of roughing. It held up to some g-loading,,but eventually started to pull.

Also used a tube of Lord adhesives for bonding UHMW sheets together for a chain guide. 510 seems to come to mind,,but better to ask Lord Adhesives.
 

dhbarr

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I guess I'm guilty of not reading all the posts when I just jumped in?

Thread drift is a thing Joe. (See Post #8) Maybe you could ask a moderator to change the thread title, since it seems to be a touchy subject.
Not cardboard, a cardboard motor mount tube.
I didn't think I'd have to explain that I'd want is to be successfull, and not rip the motor mount tube. Ruining the motor tube would be a non-starter for me.
If I had a point, which I usually don't, it would be that this is a failure of the tube, not a failure of the glue. Hence mentioning a backing ring, and also my contrived example of school glue and tissue paper.

It just so happens, though, that circling back around to the top-topic.... I was chatting with a couple of church friends ( woodworker, boat guy ) and "Star Board" is a thing used on boats, and it's essentially just HDPE sheet. So all these folks have spent a LOT of money trying to figure out which adhesives work in this context, orders of magnitude more than we have in rocketry. And the argument threads are freely perusable online.
* G/flex 655
* 3M 5200
* Lord 7542 AB
* 3M DP-8005
* MarineTex FlexSet
* ChemSet 6105 / 6110

These last ones especially looks a little interesting.
 
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jqavins

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If I had a point, which I usually don't, it would be that this is a failure of the tube, not a failure of the glue. Hence mentioning a backing ring, and also my contrived example of school glue and tissue paper.
I thought that controversary was over, but since you've brought it back (why don't you give me a paper cut and pour lemon juice in while you're at it?) I'll say what I realized some time ago that I should have said in the first place:

Lake, I started the thread purely about material properties, and you brought up applications. We talked about the protein content of various flours and you brought up cake recipes. (Is that a bad metaphor? I suck at metaphors.)
 

dhbarr

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I thought that controversary was over, but since you've brought it back (why don't you give me a paper cut and pour lemon juice in while you're at it?) I'll say what I realized some time ago that I should have said in the first place:

Lake, I started the thread purely about material properties, and you brought up applications. We talked about the protein content of various flours and you brought up cake recipes. (Is that a bad metaphor? I suck at metaphors.)
SEE THE THING ABOUT RICE FLOUR GLUE IS
 

lakeroadster

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I thought that controversary was over, but since you've brought it back (why don't you give me a paper cut and pour lemon juice in while you're at it?) I'll say what I realized some time ago that I should have said in the first place:

Lake, I started the thread purely about material properties, and you brought up applications. We talked about the protein content of various flours and you brought up cake recipes. (Is that a bad metaphor? I suck at metaphors.)
Let them eat cake! What's a Meta for?

No worries Joe... I'm so past this.

As to my part in this adventure... I was spurred into action by this ludicrous statement....

Nothing is unglueable. You just need the right glue.
Later posts reigned the statement back into the corral of logic and proportion. At the time of this flurry of postings I was designing the tri-motor for my Mercury Abort rocket. On a different thread @BABAR had suggested the use of a motor retaining device, like a motor hook, due to the cluster firing multiple ejection charges and the pressures related thereto. The issue is the cluster doesn't lend itself to the use of a std. metal hook, since this is a minimal diameter design and the BT-50 motor tubes are all visible.

Mercury Abort Rocket Dwg Sheet 9 of 14 Rev 06.jpg Mercury Abort Rocket Dwg Sheet 4 of 14 Rev 06.jpg

If there was a way to reliably glue the hook to that BT-50H, that looked attractive and was reliable, wouldn't that be lovely? So I asked, tongue in cheek...

What glue would I use to attach a spring steel engine hook to a cardboard motor tube?
That's when things went south... mostly due to me not writing all of this ^^^^ to define the application, but writing all this would have mucked up the thread even worse.

But at this point.. muckapaloosa. :headspinning:
 
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Marc_G

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By that logic, fingers are not gluable, because gluing one's fingers to things (e.g. with CA) is a bad idea.
Just for the record, fingers ARE DEFINITELY gluable.

IMG_20211227_162319.jpg


And yes, I had debonder handy. No fingerprints were lost as a result of this gluing mishap (was CA impregnating some papered fins)
 

Halvey

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Ultra thin Ca is my Arch enemy. 1 tiny drop will run and spread for 10 miles, gluing the entire county to my worktable in one big mass.

Almost glued my eyelids shut once. Had dribbled some ca into a tight fitting seam. As i was observing the flow of glue, the seam snapped closed, splashing the ca right into my eyes. The worst part was the ice cold saline solution in the ER room, as they peeled them apart and tried to flush it out. Gravel in my eyes,,for about a week. Learned a hard quick lesson.

As a ironic side note, I opened my right thumb up really deep on a spinning Derale engine cooling fan(keep your fingers out of fans when running kids). I could see muscle linkages moving inside there when I wiggled my thumb. Gaa!. The ER used the medic grade super glue to glue the skin flaps down and together,,after the iodine scrub with the toothbrush and no numbing agent. Another lesson.
 
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OverTheTop

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Ultra thin Ca is my Arch enemy. 1 tiny drop will run and spread for 10 miles, gluing the entire county to my worktable in one big mass.

Almost glued my eyelids shut once. Had dribbled some ca into a tight fitting seam. As i was observing the flow of glue, the seam snapped closed, splashing the ca right into my eyes. The worst part was the ice cold saline solution in the ER room, as they peeled them apart and tried to flush it out. Gravel in my eyes,,for about a week. Learned a hard quick lesson.
A guy I used to work with was gluing with CA. He applied the glue and then hit it with a squirt of activator. The blob of glue skinned, built up pressure and then ruptured, squirting him just under the lower eyelid. Very lucky. Since then (late '80s) I always use safety glasses when using CA, and recommend the same to everyone else.
 

lakeroadster

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A guy I used to work with was gluing with CA. He applied the glue and then hit it with a squirt of activator. The blob of glue skinned, built up pressure and then ruptured, squirting him just under the lower eyelid. Very lucky. Since then (late '80s) I always use safety glasses when using CA, and recommend the same to everyone else.
Even better, Safety Goggles. Something that fits tight around the eyes.
 

bjphoenix

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Anybody ever heard of DAP RapidFuse? I saw it mentioned in a youtube home improvement video. DAP says it "bonds virtually everything".
 

jqavins

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No, I haven't seen or heard of it. I have read labels on other glues with the same claim, and usually the reason they say "virtually everything" is that the won't bond polyethylene, polypropylene, PTFE (Teflon) or ETFE (Tefzel).
 

lakeroadster

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If I had a point, which I usually don't, it would be that this is a failure of the tube, not a failure of the glue. Hence mentioning a backing ring, and also my contrived example of school glue and tissue paper.

It just so happens, though, that circling back around to the top-topic.... I was chatting with a couple of church friends ( woodworker, boat guy ) and "Star Board" is a thing used on boats, and it's essentially just HDPE sheet. So all these folks have spent a LOT of money trying to figure out which adhesives work in this context, orders of magnitude more than we have in rocketry. And the argument threads are freely perusable online.
* G/flex 655
* 3M 5200
* Lord 7542 AB
* 3M DP-8005
* MarineTex FlexSet
* ChemSet 6105 / 6110

These last ones especially looks a little interesting.
How long, I wonder, until that window gets busted behind his workbench?

When Testing Goes Wrong.jpg
 

DES

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Regarding Teflon --- Teflon can be glued.

Quoting directly from the Pemabond website, Permabond® Polyolefin Primer (POP) has been developed for surface treatment of polyolefins, PTFE and silicones prior to bonding with Permabond® Cyanoacrylate adhesives.

TDS for the primer is attached. 4 Mpa is about 600 psi. Not awesome strength, but not bad either.


Surface preparation and PTFE adhesive selection
Before the introduction of special primers such as Permabond POP or structural acrylics such as Permabond TA4610, fluorocarbon etchants were used to pre-treat the PTFE to allow adhesive bonding. These materials are becoming more difficult to get hold due to shipping hazards and many workplaces are trying to lower worker exposure. Using an etchant allows great freedom of choice of industrial adhesive after treatment – this could be important if you have other performance considerations.

Permabond POP Primer and cyanoacrylate adhesive combination work well on PTFE. Brush the POP Primer onto the untreated PTFE surface before bonding with any of the Permabond cyanoacrylates. Permabond 105 is particularly good but if you require high temperature resistance then Permabond does offer cyanoacrylate which will go up to 250°C (482°F). There are limitations though – if you are bonding dissimilar surfaces, opt for a toughened grade such as Permabond 737 which will allow some flexibility to cope with differential expansion and contraction. Cyanoacrylate gap fill is limited to 0.5mm and they are unsuitable for spreading over large areas.

Permabond also offers TA4610 (and a range of similar products with varying cure speeds). This is a two-component 1:1 mix ratio structural acrylic which can be applied, without primer, to untreated PTFE surfaces and achieve a reasonable bond strength on this non-stick nasty!
 

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DES

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Anybody ever heard of DAP RapidFuse? I saw it mentioned in a youtube home improvement video. DAP says it "bonds virtually everything".
RapidFuse is a toughen gel type, high grade CA. Good product as CA goes, but not really much different than other toughened CA. DAP also sells the same Rapid Fuse with a vial of primer (most likely just heptane) for plastic bonding.
 
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