Fillers and diluting / thinning

[Zack]

Dear BM friends.

not sure if I have landed correctly in this section, but here we go:

 

I am (still) trying to learn best practice when it comes to working with fillers.
I have seen many references to so called "sprue goo", plastic sprue diluted in Tamiya Extra Thin cement.
Sounds "hot" and a bit dangerous with large amounts of solvents.

Ideally I would want something that is easy to apply and were excess can be easily wiped off or later easily sanded off.

 

I was not the brightest shining light in chemistry class and must admit that many fillers available nowadays are new to me.

Could you help me with two questions please:

#1.)  How would you thin/dissolve the following fillers:
Perfect Plastic Putty, Deluxe

Plastic putty 70.401, Vallejo

Tamiya  Putty White, Tamiya

 

#2.) What would be your preferred filler.

 

Thank you in advance and sorry if I am posting in the wrong thread.

Stay safe!

Zack
 

 

[roginoz]

 

Deluxe PPP thins in water. Suitable for small gaps, it can be cleaned off with a wet cotton bud. Powders when  sanded.

Valejo PP  70-401 likewise. I've found little difference between the two fillers but Vallejo seems the more robust. Does not powder when sanded.

Tamiya White [or grey] cleans up in IPA. As above.

 

I use all three, plus a number of others, depending on the job required.

For larger gaps, I'll tend to use a wedge of plastic sheet filled with one of the above and wiped off or sanded as appropriate.

Hope that helps.

Rog

 

[ckw]

I have tried a number of Plastic Putty type fillers but have been unhappy with them because they tend to crumble at the edges when re-scribing. 

 

My preferred options are sprue-gloop which you already know about, and a superglue/talc mix which is my favourite for speed, final finish and re-scribing. But you have to work fast, and really only good for small areas (e.g. seams). 

 

For  deep repairs I like Milliput fine (the white stuff) which is really strong. It takes a while to harden but can be worked with water until it does. But it can crumble when scribed, so once the bulk of the gap is filled, I'll add a final layer of superglue/talc

 

Cheers

 

Colin

[Flying Badger]

I tend to use Perfect Plastic Putty and as others have said it thins with water. 

I get a fine dust when sanding but it feathers fine and a wipe over with a damp bit of kitchen towel takes care of the dust. It fills thin gaps etc. For large gaps I stick a piece of plasticard in with Tamiya extra thin cement /liquid poly and when it's dry I cover any edges etc. with the PPP. It sets fast too which is great.

 

This image has all three: the rectangular slot on the side is filled with plasticard with PPP over the top, the thin line is filled with PPP and the surface variation on the flat is feathered with PPP. Sanded with a course then fine stick followed by a polishing stick. 

 

The only caution I'd offer is to make sure any seam between two surface panels is well bonded with glue before filling. There is no flexibility in the PPP and I have had seams show through the paint when the PPP has cracked along a poorly bonded seam.

Milliput is much better in that regard as it forms a much stronger bond and is good for larger gaps - often seen it used for airliner windows where something like PPP might pop out leaving a hole.

 

The Vallejo 70.401 I assume is a tube version of the 70.400 as both say they are acrylic resin based. The 70.400 you could mix with water or Vallejo's acrylic thinners (never an alcohol based thinners if it's like the rest of Vallejo acrylics range) to thin it down. I assume the 70.401 version is the same. 70.400 worked OK but I don't have a good local source any more so I've only used it a few times.

 

Other options I've tried are Mr dissolved putty, superglue and talc / baking soda and Mr Surfacer 500 / 1000 / 1500.

I found Mr Dissolved Putty a bit soft when set and my jar has dried out now (although it can revitalised with some lacquer thinners).

CA glue and talc / baking soda is a great gap filler and it's fast. Can be a bit brittle and the baking soda version is very exothermic (generates heat as it sets) so don't do too large an area at a time.

The Mr Surfacer stuff is great stuff and I often paint a thin layer over the PPP as it helps harden up the surface. It's thinnable with Lacquer thinners (Tamiya or Mr Hobby) and can even provide a microfilling primer that airbrushes (essentially the same as Tamiya Fine Surface Primer but not in a spray can).

I've also used small amounts of 5 min epoxy with some talc mixed in - that works OK but can be a bit awkward to sand. Its fast though.

Obviously I've also done sprue gloop - thats OK but takes ages to set and smells and can melt surrounding plastic parts. I also find it stays soft for a long while.

 

[Evil_Toast_RSA]

5 hours ago, Zack said:

#1.)  How would you thin/dissolve the following fillers:

X

X

Tamiya  Putty White, Tamiya

 

 

 

The PPP and Vallejo has been covered quite well at this point. 

 

Tamiya White/Grey putty can be thinned with Lacquer/Cellulose/Whatever its called in your country, Acetone and even Extra Thin/MEK if you want. Depends how much you want it to bite into the plastic. If your not keen on on those, a "gentler" Lacquer thinner like Tamiya and MLT can be used. 

 

As for #2, it really depends on you and what your doing. PPP is great for fine gaps etc, but filing a big gap it will probably be best to use something else. 

[Flying Badger]

1 hour ago, Evil_Toast_RSA said:

 a "gentler" Lacquer thinner like Tamiya and MLT can be used. 

Just for clarity that is Tamiya Lacquer thinner (#87077) NOT the usual Tamiya (X20A) thinner (X20A is alcohol based) used for most Tamiya acrylic paints.

MLT = Mr Colour Thinner or Mr Colour Levelling Thinner (by Mr Hobby) both of which are lacquer based thinners, the latter has some paint retarder and flow improver to help it level out the paint and slow drying down when airbrushing - great stuff.

 

 

 

[Evil_Toast_RSA]

22 minutes ago, Flying Badger said:

Just for clarity that is Tamiya Lacquer thinner (#87077) NOT the usual Tamiya (X20A) thinner (X20A is alcohol based) used for most Tamiya acrylic paints.

MLT = Mr Colour Thinner or Mr Colour Levelling Thinner (by Mr Hobby) both of which are lacquer based thinners, the latter has some paint retarder and flow improver to help it level out the paint and slow drying down when airbrushing - great stuff.

 

 

 

 

This stuff: https://www.tamiya.com/english/products/87194/index.htm. Also available without a retarder. 

 

No idea where it's available in the world, this conversation gets really interesting sometimes! 

 

[EDIT] I think for clarity sake, both Tamiya orange/yellow cap and MLT are "gentler" in the fact that you probably will still see pink elephants if you inhale to much of it, but you wont turn the plastic on your model into goo if you use it to wipe the dried filler off using it. 

Edited June 14, 2022 by Evil_Toast_RSA

[Flying Badger]

That's the stuff - bought a new bottle recently from a little known online retailer called Amazon* 😉

 

Like many paints it's not supposed to be allowed in royal mail so it has to go via courier instead. 

 

 

 

*although emodels and wonderland models both had some in stock as well when I looked.

 

[dnl42]

I regularly use Mr.Color Thinner for stripping parts or even whole models to refinish--safe for plastic, including clear parts. I reserve MLT for paint thinning.

[Zack]

Thank you All! 

Really very much appreciated! 

Almost midnight here in Gothenburg so will come back tomorrow with follow up questions, if any, but for the time being;

Thank you All for your time, great suggestions and advice!!! 

 

Stay safe, stay sane and till next time:

Happy modelling 😀

Zack

[Mike]

These are the things I use:

• Tamiya Basic Putty for shallow sink marks, sometimes with a smear of CA over it to make it less absorbent before painting.
• Mr Surfacer 500, 1000, 1500 etc. for really fine lines and sands quickly.
• Styrene sheet/rod to backfill long gaps and reduce the use of fillers.  Makes for a structurally strong joint too.
• Super Glue (CA) for gaps, seam lines, repairs etc.  It cures quickly, and as long as you sand it back as soon as it's cured, it's good stuff.  leave it overnight and it will cure to full strength and be tougher than the plastic, making sanding more difficult.
• Milliput is great for filling large gaps and making up shapes.  It smoothes with water, sands well, cures underwater (not that it matters), is drillable and tough.  Takes a good few hours to cure though, especially in cold weather.
• Polyfilla.  No, I'm kidding.  That would be foolishness!

[Flying Badger]

1 hour ago, Mike said:

• Polyfilla.  No, I'm kidding.  That would be foolishness!

🤣

 

However now you mention it.... I have used polyfilla to make moulds to duplicate simple aircraft pieces in the past and even as weight inside the nose of an airliner (fill nose of both fuselage halves with polyfill, remove when set and sand centre face flat then glue back in and the two halves should fit together nicely) so it's not that crazy.