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Discussion Boards => General Discussion => Topic started by: Dave T on March 15, 2007, 11:30:29 PM

Title: Model flaws
Post by: Dave T on March 15, 2007, 11:30:29 PM
What material is good to fill in seams and holes in plastic models?
Thanks....
Title: Re: Model flaws
Post by: brad on March 15, 2007, 11:43:55 PM
For gouges and scratches I use Squadron  Green Putty, For small holes, I heat a piece of parts sprue from a kit and stretch it to for a tapered piece. I then stick it in the hole and cut it off so a bit of the plug sticks out from either side. Then I put it in the hole and apply some Ambroid plastic weld and let it cure, usually over night. Then I trim it as close as I can with a razor blade or knife and sand it smooth. For large holes I cut a piece of styrene to fit and glue that in place with Ambroid, then sand and fill any imperfections with green putty.

brad
Title: Re: Model flaws
Post by: daniel_leavitt2000 on March 16, 2007, 12:07:10 AM
You can also use Milliput. This is an epoxy with clay mixed in to produce a water-soluble body putty that is much easier to work with then Squadron, and will not shrink or crack over time.
Title: Re: Model flaws
Post by: gardenrail on March 16, 2007, 05:18:37 AM
I certainly agree about using Milliput. It's available in two grades - Standard (Grey/Yellow) and Superfine (White). Depends on the job which one is better.
Title: Re: Model flaws
Post by: ebtbob on March 16, 2007, 07:42:15 AM
Brad,

      You mentioned Squadron Putty.   Do you know why they offer it in both green and white and is there any difference other than the color?

Bob Rule, Jr.
Hatboro, Pa
GATSME MRRC
Narrow Gauge Chairman
Title: Re: Model flaws
Post by: Dave T on March 16, 2007, 08:41:28 AM
Hmmmm....Milliput...Is that auto body stuff?...Sounds like that might be my answer. Thanks, Guys.
;D
Title: Re: Model flaws
Post by: Rich R on March 16, 2007, 10:52:46 AM
Quote from: ebtbob on March 16, 2007, 07:42:15 AM
Brad,

      You mentioned Squadron Putty.   Do you know why they offer it in both green and white and is there any difference other than the color?

Bob Rule, Jr.
Hatboro, Pa
GATSME MRRC
Narrow Gauge Chairman

Hi Bob,

To the best of my knowledge the difference is only for painting. The darker colour would need a heavier coat of primer to cover so they made the white I think for the auto/aircraft  modelers. Armour models being darker for the most part aren't as problematic. I may be wrong but that's how I always used the stuff.

Best,
Rich R
Title: Re: Model flaws
Post by: lanny on March 16, 2007, 11:21:36 AM
Hi all,

Personally, like Brad, I always use 'Green Squadron Putty' ... it is really fast drying, very easy to work with, and sands/smooths wonderfully well. It will accept 'wet sanding' with very fine grit emery paper which really gives a beautiful surface.

When I purchased a tube at the LHS, the guy didn't know what the difference between the green and the white was. I think Rich R. is probably 'right on' in the reason for the color difference.

Again, I want to emphasize the tremendous ease of smoothing, sanding and contouring using Green Squadron putty. I am finishing up an very old, vintage,Bowser white cast metal (not the new zinc boiler) boiler. Squadron putty is recommended on the surface to cover blemishes in the metal and then final wet sanding for a really nice, smooth surface.

It works not only well on plastic, but on metal too (soft, heavy, whie metal casting type metal), though there may be some metals it will not adhere well to.

lanny nicolet
Title: Re: Model flaws
Post by: Rich R on March 16, 2007, 01:51:01 PM
Quote from: Dave T on March 16, 2007, 08:41:28 AM
Hmmmm....Milliput...Is that auto body stuff?...Sounds like that might be my answer. Thanks, Guys.
;D
Hi Dave,

I'm not certain it's for use as an autobody filler but if you could afford it, it would probably work.  ;)
Micro Mark carries it here in the US and it's an interesting read on their web site. You might wish to check it out as it can be rolled into flat sheets as thin as 1/64th and then used after it hardens. I've seen some seriously good stuff molded from it out of the UK.
Like I said, check Micro mark.

Best,
Rich R
Title: Re: Model flaws
Post by: brad on March 16, 2007, 08:12:47 PM
Bob,

I think Rich has the answer. I used it when I built a lot of military kits, so I kept using it. For filling casting flaws in metal parts you might use "spot putty" for autobody work. It is used for filling small scratches and knicks before finall primer and paint. It is quite inexpensive. I've never tried it on plastic though.

One thing I forgot to mention is that after I aplly the putty I give it a drop of Ambroind plastic weld to give it some extra tooth to adhere to the plastic. I think it already has a type of adhesive in it to melt the plastic but I always give it a little shot to be sure. Again I let it cure  overnight before sanding.

brad
Title: Re: Model flaws
Post by: ebtbob on March 17, 2007, 07:03:46 AM
Good Morning All,

     Thanks for the answer to my question on the color of the Squadron Putty.   Ironically,  I too,  work partime,  in a trainstore and have been asked that question.    All these years,  I have been giving the correct answer,  but now I know it is correct and have a reason to recommend one color of the other.

Bob
Title: Re: Model flaws
Post by: 0n30nutz on March 17, 2007, 12:00:21 PM
   Squadron Green is my choice for filling larger gaps and seams, but for smaller seams, gaps, etc. I use gap filling ACC...it tends to flow nicely into gaps, self levels, and sands well. If at all possible, back up the area to be filled, and don't use thin ACC...it does flow everywhere!!!

Howard
If it ain't steam, it ain't
Title: Re: Model flaws
Post by: scottychaos on March 17, 2007, 03:13:32 PM
Green vs. White squadron putty.
there is more to the story!  ;)

what I heard, (back in the 1980's) is that the difference has to do with the color of the plastic you are filling.

because..

lets say you are building a model with white styrene, and you have a gap to fill. You put a blob of white putty on white styrene, push it into the gap, let it dry, and start to sand...you cant tell where the putty ends and the plastic begins!
so you are sanding away..you think "am I sanded down enough? I cant tell..I will try painting my model..oh no! there is still a visable hump of putty!" having the color of the putty be the same color as the plastic is bad..because you cant tell when you are fully sanded down.

Now you use GREEN putty on that same white sytrene.
you start sanding..
now you can see the difference between the putty and the plastic!
you can sand right down so that ONLY the green putty in the gap remains..
you can clearly see where the plastic leaves off and the putty begins..
now when you paint, you have a nice smooth transition.

the different colors of putty is for use on different colors of plastic.
so you can see what you are sanding away and not sanding away.

I suppose green can be used on just about anything then, except green plastic! which is pretty rare.

I have never used the white myself, but have been using the green for 20 years..that difference in color between the model and the putty is really handy and necessary.

Scot
Title: Re: Model flaws
Post by: lanny on March 17, 2007, 11:36:56 PM
Scot,

Your explanation of the difference in white and green Squadron Putty is very helpful to me. Thanks! (think I'll just keep using the green, since I am now building a lot of 'white' resin' kits  :-)

lanny nicolet
Title: Re: Model flaws
Post by: WoundedBear on March 20, 2007, 05:18:57 PM
For filling holes try thin CA and baking soda. Back the hole with a piece of masking tape, fill hole level with the baking soda.....1 or 2 drops of thin CA and it sets instantly. I have used these materials in many many automotive replica builds.

I used thick CA to mold in panels when relocating fenderwells. Make clean careful cuts.....bond with the thick CA and use a kicker.

When it comes times to file and sand, you'll end up using no "putty" at all on your seams and holes.

Sink marks and shallow dips still need to be puttied, but overly deep ejection pin marks can be filled successfuly with the CA/Baking soda trick.

And a bonus....the CA/baking soda mixture never shrinks.

Sid
Title: Re: Model flaws
Post by: Loco Bill Canelos on March 20, 2007, 06:44:18 PM
I am with Scot, on this one and have used it for the same reason on my kitbashes.  I don't worry about the color contrast, since I give my kit bashes a coat of primer before final painting anyway. 

Thanks for all the great responses, there are certainly a lot of great techniques out there and I love learning all the new tricks!!
Title: Re: Model flaws
Post by: r.cprmier on March 22, 2007, 07:58:02 AM
Wounded Bear;
That is a good idea.  Steve Funaro, of F&C Models, recommended it to me at a show once, and it is also in some of the literatrre in their kits.  It does work very well.


Rich