How do you remove excess glue before priming?

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dk54321

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When I've finished building a rocket and I'm preparing to prime it, I find I usually have little lumps of excess wood glue--fingerprints, drips, etc., that are small enough to be almost invisible before painting, but big enough to be noticeable under primer and paint, especially if I apply a glossy finish. Wood glue doesn't sand all that well. I can scrape it off with a hobby knife, but it's easy to accidentally gouge paper or balsa, leaving a bigger blemish than I started with.

Do you have a better technique?
 

dhbarr

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Nitrile gloves doubled up. Get one too goopy, shuck it and grab another.
 

dk54321

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Good idea to prevent glue spots in the first place. Any ideas how best to remove them once they're there?
 

GregGleason

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From Titebond: https://www.titebond.com/frequently_asked_questions.aspx

[h=4]How do I clean up wet glue or remove dried glue?[/h] For most of our water-based wood glues, it is often best to use a damp cloth and remove excess glue before it has dried. After the glues have dried, scraping or sanding works well. Steam from an iron may also be effective, but it will not take the glue out of the pores of the wood. When wet, the Titebond Polyurethane Glue may be removed with acetone, but it is much easier to chip off the foam after the glue has cured. Once dry, Titebond Instant Bond Wood Adhesives may be removed with acetone or sanding.
As you can see, the best approach may be tied to which type of wood glue.

Greg
 

Micromeister

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Most wood glues will sand with 240 -320 grit papers. Takes a little time to remove ONLY the glue but you'll be happier then trying to use a #11 knife blade or razor blade.

Both blade "SCRAPPING" choices can be used holding the blade perpendicular (90degs) to the body tube with success.
What your are actually doing is using these blades as "Scrapers" do not apply much pressure simply scrap back and forth over the glue spot to shave off tiny bits at a time. It is very important to keep the blade at 90 degrees to the body to prevent gouging. Sandpaper or Blade Scraping both ways do take time and patients. That said your finish will end up much better.
I use both methods often on many glue and adhesive types. My suggestion is to first try Sanding with a sanding block or sanding stick (240-320 grit). If that is not removing your problem area, then try the blade scrapping method. keeping your blade 90degrees to the body tube.
 

rharshberger

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White glues and wood glues can be softened with vinegar allowing them to be scraped away, just be careful not to soak the cardboard, as the vinegar takes 15mins or so to work. I have dismantled antique chairs that were repaired with wood glue using this method.
 

KenECoyote

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If they're not really noticeable before you prime, use filler primer, lay it on as heavy as you need, sand overall, repeat if needed and paint the final color. If they are noticeable before you paint, file, sand, scrape as needed.

I did this for my Estes Silver Comet (with a final coat of chrome paint):
 
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dr wogz

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From my experience, wood glue (the yellow 'Aliphatic resin') is easy to sand off once dry. Much easier than CA or epoxy. 120-240 grit as mentioned, in little swirly motions on the glue area usually does the trick.

Of course, as others have mentioned, clean them up before they harden, and use only as much glue as you need.. Keep a piece of paper towel handy (in your other hand) to wipe up any drips or spills, and to wipe your finger form smearing or laying down fillets.. I have the nasty habit of wiping my gluey finder on the lower edge of (under) my work-bench. so, it has all these 'glue drips / glue stalactites hanging from it!
 
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