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Liquid Cement joining and capilary action?
Marc2109
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Ohio, United States
Joined: December 21, 2014
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Posted: Friday, December 26, 2014 - 12:12 AM UTC
If read these posts about joining fuselage halves, etc, using liguid cement and capilary action. Problem is I can't get it to work. I have one of those thin glass tubes with a tiny metal tube on the end to use with Tenex. I am holding the parts together, and applying the cement to the outside. It always marres up the parts. It will not run down the seem, so I have to try to guide the tube down the seam, which I never get straight, and it messes up the plastic. Obvioulsy I am not doing it right.

Is there a video on this somewhere? I am suppose to be applying the solvent to the outside of the seam, correct?

What is suppose to happen with this capilary action?
raypalmer
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Ontario, Canada
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Posted: Friday, December 26, 2014 - 01:33 AM UTC
If you get some of those precision little swabs. Just went it with tenax, then (holding two halves tightly together, that's important) touch it to the tightly closed seam. The tenax will be drawn into the seam. I don't recommend using the little tube thing. It will get tenax everywhere.
Marc2109
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Ohio, United States
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Posted: Friday, December 26, 2014 - 02:13 AM UTC

Quoted Text

If you get some of those precision little swabs. Just went it with tenax, then (holding two halves tightly together, that's important) touch it to the tightly closed seam. The tenax will be drawn into the seam. I don't recommend using the little tube thing. It will get tenax everywhere.



Wow great tip!! Glad I asked!
raypalmer
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Ontario, Canada
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Posted: Friday, December 26, 2014 - 02:17 AM UTC
If the seam is airtight the tenax won't flow though... Ease off pressure if it doesn't work
It's only needs a wee little crack to flow.
Marc2109
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Ohio, United States
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Posted: Friday, December 26, 2014 - 02:27 AM UTC

Quoted Text

If the seam is airtight the tenax won't flow though... Ease off pressure if it doesn't work
It's only needs a wee little crack to flow.



Gotcha
Jessie_C
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British Columbia, Canada
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Posted: Friday, December 26, 2014 - 03:23 AM UTC
You can also try a fine pointed brush. Sometimes the glue evaporates quite rapidly so you have to act quickly.
Joel_W
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New York, United States
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Posted: Sunday, December 28, 2014 - 10:05 PM UTC
There's a fine line between the parts not being tight enough, and too tight. It takes a few tries to get it right. I Generally find that at the pressure of just making contact is a good starting point.

I like to tilt the seam rather then in a level position as it does aid in proper capillary action.

You will get a glue stain where you touch the model. That's normal. Once dry, it's very easy to sand and polish out the seam.

My preferred glue is Tamiya Extra Thin. I really like the small applicator brush it comes with. If you're using a brush, you want a medium stiff bristle about a 1/4 inch in length. I find that the glue will run down hill about a inch at a time. So I plan accordingly. I also run the brush alone a seam like the leading and trailing edge of a wing. Clean up is generally very easy: #320, 600 both wet, then Micro Mesh pads or cloths 4000, 6000, 8000, & 12000.

Joel
Marc2109
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Ohio, United States
Joined: December 21, 2014
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Posted: Thursday, January 15, 2015 - 12:13 AM UTC

Quoted Text

There's a fine line between the parts not being tight enough, and too tight. It takes a few tries to get it right. I Generally find that at the pressure of just making contact is a good starting point.

I like to tilt the seam rather then in a level position as it does aid in proper capillary action.

You will get a glue stain where you touch the model. That's normal. Once dry, it's very easy to sand and polish out the seam.

My preferred glue is Tamiya Extra Thin. I really like the small applicator brush it comes with. If you're using a brush, you want a medium stiff bristle about a 1/4 inch in length. I find that the glue will run down hill about a inch at a time. So I plan accordingly. I also run the brush alone a seam like the leading and trailing edge of a wing. Clean up is generally very easy: #320, 600 both wet, then Micro Mesh pads or cloths 4000, 6000, 8000, & 12000.

Joel



Thanks Joel. I got some and it is working out great. I need to get some of those super fine sanding and ploshing tools though..the smallest I have is 600.
Joel_W
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New York, United States
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Posted: Thursday, January 15, 2015 - 12:28 AM UTC
Marc,
Glad it's working out for you.

If I'm not looking to do a gloss or NMF, then just 4,000 will do perfectly well.

Joel
Dragon164
#226
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British Columbia, Canada
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Posted: Thursday, January 15, 2015 - 03:05 PM UTC
I too use Tenax and my prefered method of application is one of those cheap white Testors brushes and I run the brush along the seam.

Cheers Rob.
rklouie
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Ontario, Canada
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Posted: Sunday, January 25, 2015 - 09:41 PM UTC
Here's the youtube video from Gerald (Hawkeye Hobbies) on using the touch and flow:

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