Best way to clean up ejector pin marks ?

[Goodwrench3]

Hi all:

Looking for the best way to remove ejector pin marks in parts like frame rails, etc. (I assume they are "ejector pin" marks -- small circular marks on the inside of the frame rails).

Are you typically just sanding down the plastic until you get a smooth surface ?

Are you filling them and sanding ? If so, what type of filler are you using ? The marks in my frame rails are not deep, so I'd need something pretty thin.

Or just masking off the area of the mark, spraying primer, then sanding that area ??

Many thanks for the help -- I know it's a "newbie" question.

[Ken Gilkeson]

I use a little battery powered grinder made for pedicures and manicures. it came with a file bit shaped like a ball. I have seen them in harriet carter and dr. leonard novelty mail catalogs.

[Chariots of Fire]

If it's a raised mark, sand or grind it away. If it is depressed, use some filler like Squadron or Tamiya and then sand it smooth.

Edited March 28, 2015 by Chariots of Fire

[Nacho Z]

To fill in ejector pin marks, I use every day super glue. I put a small drop in the ejector pin hole. It normally fills every bit of the hole. I then hit it with accelerator, also called "kicker". It can be immediately sanded. To the best of my knowledge it does not shrink. In my experience you will want to sand it right away. I have found that it seems to get harder the longer you wait. I am talking about overnight or longer. Give it a try.

[Goodwrench3]

Thanks everyone !

[Goodwrench3]

If it's a raised mark, sand or grind it away. If it is depressed, use some filler like Squadron or Tamiya and then sand it smooth.

RE: " If it is depressed, use some filler like Squadron or Tamiya and then sand it smooth.".

So mine are some very shallow ones on the inside of a frame rail. After I fill with Tamiya White putty and sand smooth, do I necessarily need to cover the puttied areas with primer before spraying the color coat (which will either be flat or semi-gloss black) ?

Thanks again

[Matt Bacon]

Depends on how big they are, obviously, but I have a multi-size hole punch bought from the craft store (used for leather punching), which I use to punch out discs of plastic card of the necessary size and thickness. They glue in place, and since they're the same material as the kit parts, they can be primed and sanded just like the rest of the part. I find it helps prevent the "dishing" that you sometimes get with filler, when the softer filler in the middle sands away faster than the surround, leaving a depression -- it's better than the pin mark but can still be visible. With various thicknesses of plastic card, you can deal with anything from the "barely there" pin mark, which is mostly a rim of flash around the edge, to some of the really deep impressions you find on older or badly tooled kits....

bestest,

M.

[fseva]

Hi all:

Looking for the best way to remove ejector pin marks in parts like frame rails, etc. (I assume they are "ejector pin" marks -- small circular marks on the inside of the frame rails). Are you typically just sanding down the plastic until you get a smooth surface ?

You could also be referring to "sink marks". These are the type that you find in just about every AMT kit on the interior floor, and they're a real pain, given that you might not want to lose the nice engraving that's already there (depicts carpet). My question to you is, "Is this car being built for competition, or do you intend it to be accessible to visitors who will be allowed to handle the model?" If your answer to no to both questions, my motto is... if you can't see it, don't do it! This may upset some diehards out there, but hey, they'll never see it... so, why should I take the extra time on it?!

[Goodwrench3]

Yeah -- you are right. I tend to get a little too particular about some of this.

Esp. after it's done and "under glass" ... if it looks good from a foot away, it's good enough.

While you are working the parts, it looks like a big deal. But... it's the old "forest and trees" thing.

[Art Anderson]

To fill in ejector pin marks, I use every day super glue. I put a small drop in the ejector pin hole. It normally fills every bit of the hole. I then hit it with accelerator, also called "kicker". It can be immediately sanded. To the best of my knowledge it does not shrink. In my experience you will want to sand it right away. I have found that it seems to get harder the longer you wait. I am talking about overnight or longer. Give it a try.

I second this one! I've been doing this very thing since the first gap-filling CA glues came out in the mid-1980's, almost simultaneously with accelerators. Quick and easy to do, and no, CA glue does not shrink!

Art

[Goodwrench3]

I second this one! I've been doing this very thing since the first gap-filling CA glues came out in the mid-1980's, almost simultaneously with accelerators. Quick and easy to do, and no, CA glue does not shrink!

Art

OK ! I'll give this a roll !!!

I normally use "Zap" brand CA as I've found it the best out there. I'm guessing you are using something like their medium "CA+" (or "Zap-A-Gap" green label) and not the super thin "ZAP CA" (pink label) ??

Thanks for the help