Wood Glue on Plastic Nose Cones

[UrbanKnight]

Every year, a handful of my students don't pay attention to my instructions not to glue their nose cone with the yellow and white glue I provide them. I warn them that I will not let it fly if I can pull the nose apart on the morning of the launch, but I can never do that. Furthermore, I've actually had a few nose cones glued with Testor's model glue come apart on flights, most likely because it had gotten too hard from storage before use.

Should I relax my policy and save a few bucks by letting them use the wood glue? We're building LPR rockets that can only take up to C motors (and only using A's on the school grounds) and it seems to hold better than their fins do.

 

[T-Rex]

If it ain't broke..... I use wood glue for tail cones and such all the time. Scuff the surface well, and when the wood glue dries it forms an interference so the parts cannot separate. Depending on the age of the children, it may be smarter to allow the wood glue since it seems to do the job.

 

[JeromeK99]

Bring a bottle of CA and some kicker for quick fixes!


Jerome

 

[shreadvector]

Your use of woding makes me ask the following questions to clarify:

you say "wood glue" but then you say "Testor's Model Glue". Testos's makes "Cement" and not "Glue", so are we actually talking about the "Testors Wood Cement", which is thier version of an "Ambroid" type product which contains solvent and is best used for cementing model airplane wing ribs and stifeners? It is not very good at cementing Model Rocket fins to glassine coated body tubes nor is it good at cementing thrust rings inside or centering rings outside of motor mounts. Normal water based yellow wood glue is best for those.

If your students used the solvent containing Testor's Cement for Wood Models, then the solvent probably melted the plastic nose cone and shoulder enough for them to weld together. not as great as with normal Testor's Cement For Plastic Models, but good enough for small model rocket nose cones. Not good enough for plastic fin attachment to plastic rockets.

Every year, a handful of my students don't pay attention to my instructions not to glue their nose cone with the yellow and white glue I provide them. I warn them that I will not let it fly if I can pull the nose apart on the morning of the launch, but I can never do that. Furthermore, I've actually had a few nose cones glued with Testor's model glue come apart on flights, most likely because it had gotten too hard from storage before use.

Should I relax my policy and save a few bucks by letting them use the wood glue? We're building LPR rockets that can only take up to C motors (and only using A's on the school grounds) and it seems to hold better than their fins do.

 

[boomtube]

Testors’ model cement is primarily formulated for styrene plastics and it joins the parts by melting the surface areas and thus fusing them together.

Many of the plastic nosecones and other parts, we get in out kits are not styrene and Testors will often not work with these types of plastic. It may hold the parts together by “Sticking” but any good pull, yank or jerk will sever this bond.

And we all know there are many jerks at large launches.

Wood glue can have this same type of limited bonding to plastics as Testors does to non-styrene.

 

[shreadvector]

Testor's make many products.

https://www.testors.com/category/136634/Cements_&_Glues

The only "glue" they make is "super glue".

The "cements" come in several varieties.

Tube Type Plastic Cement works great for most model rockets. In the past, Estes has specified this for plastic parts and specifically said to NOT use the 'liquid' type as it tends to pool and dissolve the parts - resultng in a "transporter malfunction".

https://www.youtube.com/watch?v=ibBTZyQpVAA


As I stated above, the "Cement For Wood Models" contains a solvent and may slightly melt the plastic arts to form some kind of a bond. It is not a "wood glue". It is more like the Ambroid Cement used for lightweight model airplanes built up from sticks of balsa and covered in tissue.

Testors’ model cement is primarily formulated for styrene plastics and it joins the parts by melting the surface areas and thus fusing them together.

Many of the plastic nosecones and other parts, we get in out kits are not styrene and Testors will often not work with these types of plastic. It may hold the parts together by “Sticking” but any good pull, yank or jerk will sever this bond.

And we all know there are many jerks at large launches.

Wood glue can have this same type of limited bonding to plastics as Testors does to non-styrene.

 

[TopRamen]

I bet they'de get a kick out of it if you snuck in a B or C Motor.

 

[RodRocket]

I use elmers wood glue on small nose cones without any problems. I will scratch the shoulder with a knife and then drill a few small holes. Give the nose cone a twist and the glue will work into the scratches and holes. Haven't had a cone come off yet.

Now if it is plastic to plastic bond, then the model cement should be used.

A drill bit that fits in one of those quick change bit holders could be used. Use the drill point to scratch the shoulder then just twist the drill bit with your hand to make the holes. No power tools needed, or sharp knives.

 

[JeromeK99]

Another thing that came to mind...

Tell your students "not" to use the "Non-Toxic" model cement (Testors Blue tube). This stuff is pretty useless but often over protective Mom's like to buy it rather than the normal good stuff (Testors Red tube).


Jerome

 

[UrbanKnight]

Your use of wording makes me ask the following questions to clarify...

Sorry for the confusion and my incorrect terms. I usually use Testors cement for plastics on nose cones.

The wood glue my students have successfully used is Elmer's Carpenter's.

I still have one of my student's rockets from last year (he never took it home) that has the wood glue holding the nose cone together, and for the life of me, it's going to crack before I get the pieces apart.

Testors’ model cement is primarily formulated for styrene plastics and it joins the parts by melting the surface areas and thus fusing them together.

Many of the plastic nosecones and other parts, we get in out kits are not styrene and Testors will often not work with these types of plastic. It may hold the parts together by “Sticking” but any good pull, yank or jerk will sever this bond.

Makes sense. Thanks.

So what does everybody use to join parts of plastic nose cones?

 

[UrbanKnight]

I bet they'de get a kick out of it if you snuck in a B or C Motor.

The fire permit I hold restricts us to A, and the firing area is less than 500' from a major highway. I always invite them to come out to the SCRA launches where the big (to them) rockets fly, but none of them have done so yet. Too far a drive maybe. Maybe they just didn't enjoy it as much as I do. I dunno.