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Re: General Discussion

Posted: January 16th, 2012, 4:08 pm
by thsom
What glue do you guys use brand wise. I understand ca glue is good and I have tested with it, not brittle OR heavy. I have managed to build a 7.5 gram tower with it so it can't be too heavy and its strong too. If you recommend ducco and ambroid, where do you buy them and can you provide a link?

Re: General Discussion

Posted: January 17th, 2012, 6:59 am
by Balsa Man
lucwilder42 wrote:
thsom wrote:Are any of you guys familiar with stevenson? They had an amazing tower with an efficiency of about 120!!!
How tall?
Just a terminology thing, to make sure we're all on the same page. "Efficiency" (as in structural efficiency) is the weight carried divided by the weight of the tower. Score is efficiency (in kg/gr) times a height factor- for regionals, height minus 5; for State height minus 15. So, Stevenson had a score of ~120. If the tower was 70cm tall, carried all 15kg, that would mean a weight of just over 8.1 grams - an efficiency of 15/8.1 = 1.582 (in the units of kg/gr - actually 1,581- the load was 1,581 times the weight of tower); if shorter, would have been lighter- at 60cm, would have had to be about 6.9 grams- an efficiency of 2.174)

Re: General Discussion

Posted: January 17th, 2012, 12:06 pm
by thsom
Balsa Man wrote:
lucwilder42 wrote:
thsom wrote:Are any of you guys familiar with stevenson? They had an amazing tower with an efficiency of about 120!!!
How tall?
Just a terminology thing, to make sure we're all on the same page. "Efficiency" (as in structural efficiency) is the weight carried divided by the weight of the tower. Score is efficiency (in kg/gr) times a height factor- for regionals, height minus 5; for State height minus 15. So, Stevenson had a score of ~120. If the tower was 70cm tall, carried all 15kg, that would mean a weight of just over 8.1 grams - an efficiency of 15/8.1 = 1.582 (in the units of kg/gr - actually 1,581- the load was 1,581 times the weight of tower); if shorter, would have been lighter- at 60cm, would have had to be about 6.9 grams- an efficiency of 2.174)
Thank you and yes it was a score of 120. Though I believe i have a design with a score of 130 that may work. Now the actual challenge comes to precision when building.

Re: General Discussion

Posted: January 21st, 2012, 8:16 pm
by thsom
Sorry for double posting, but is "the original superglue" adequate for this, or is it too heavy or too weak because that's what I have at home.

Re: General Discussion

Posted: January 21st, 2012, 9:21 pm
by foreverphysics
thsom wrote:Sorry for double posting, but is "the original superglue" adequate for this, or is it too heavy or too weak because that's what I have at home.
It's very adequate.

Re: General Discussion

Posted: January 21st, 2012, 10:10 pm
by thsom
foreverphysics wrote:
thsom wrote:Sorry for double posting, but is "the original superglue" adequate for this, or is it too heavy or too weak because that's what I have at home.
It's very adequate.
Is it good in comparison to thin CA? Is it lighter or heavier or weaker/stronger. I'm talking about 8.5-9.5 gram 70 cm tall towers holding near all so they're pretty light, but I don't feel like going to a store to buy my normal ca glue if i already have this here.

Re: General Discussion

Posted: January 23rd, 2012, 6:33 am
by foreverphysics
thsom wrote:
foreverphysics wrote:
thsom wrote:Sorry for double posting, but is "the original superglue" adequate for this, or is it too heavy or too weak because that's what I have at home.
It's very adequate.
Is it good in comparison to thin CA? Is it lighter or heavier or weaker/stronger. I'm talking about 8.5-9.5 gram 70 cm tall towers holding near all so they're pretty light, but I don't feel like going to a store to buy my normal ca glue if i already have this here.
Image
That blue one in the picture is the best. You can get it in HobbyTown. I would also recommend getting the accelerator (the brown one). If all else fails, get the purple one. But only get that under extreme duress. That blue type is strong, efficient, and lighter than the purple. This was something we learned through a lot of experimentation...
It is under the label "Insta Cure". Make sure it's BLUE and not some other random color.

Re: General Discussion

Posted: January 23rd, 2012, 7:55 am
by lucwilder42
foreverphysics wrote:
thsom wrote:
foreverphysics wrote: That blue one in the picture is the best. You can get it in HobbyTown. I would also recommend getting the accelerator (the brown one). If all else fails, get the purple one. But only get that under extreme duress. That blue type is strong, efficient, and lighter than the purple. This was something we learned through a lot of experimentation...
It is under the label "Insta Cure". Make sure it's BLUE and not some other random color.
I must disagree with you. First, the use of accelerator in towers is a bad idea, as it dries the glue before the curing process is complete. CA takes about 24 hours to fully cure. Second, the purple stuff works perfectly. It's held together at least two medaling structures at nationals, I trust it completely.

Re: General Discussion

Posted: January 23rd, 2012, 9:58 am
by Balsa Man
lucwilder42 wrote:
foreverphysics wrote:
foreverphysics wrote: That blue one in the picture is the best. You can get it in HobbyTown. I would also recommend getting the accelerator (the brown one). If all else fails, get the purple one. But only get that under extreme duress. That blue type is strong, efficient, and lighter than the purple. This was something we learned through a lot of experimentation...
It is under the label "Insta Cure". Make sure it's BLUE and not some other random color.
I must disagree with you. First, the use of accelerator in towers is a bad idea, as it dries the glue before the curing process is complete. CA takes about 24 hours to fully cure. Second, the purple stuff works perfectly. It's held together at least two medaling structures at nationals, I trust it completely.
And I would agree with you, lucwilder42. I would add that the blue/Insta Cure is generally a bad choice. There are a few times and specific situations where its what you want, but for most, its not. It goes off really fast, which can be a real problem.

CAs come in a variety of speeds and viscosities. There are many brands- I suspect, but haven't done the research, that there are only a few actual manufacturers that actually make the stuff, and a lot of different suppliers that get it in bulk and bottle it under their brand.
In general, the thinner, runnier, lower viscosity, the quicker it "goes off." At the other end of the spectrum, are thicker/slower preparations. In general, having time to position (and re-position if needed) pieces before the glue goes off helps for a good build.

Re: General Discussion

Posted: January 23rd, 2012, 12:33 pm
by foreverphysics
It has worked best for our team. I'm just speaking from my own personal experience.