What is the best putty?

I use several puttys / fillers based on need.  I do use Perfect plastic putty often since it cleans up with water but for large gaps it does crack.  Mr surfacer 500, 1000 and 1200 morks much the same as PPP but cleans up with lacquer and wet sands unlike PPP.

I use Squadron green, red and white but thin it down as I find it to thick and dries to fast out of the tube.

When I need to avoid shrinkage when dry, I use super glue with and without baking soda powder.

Before applying any putty, I'll scuff the area with a gray scotchbrite pad, it gives some fine tooth for putty to stick to and helps keep the edges from peeling up and flaking when you sand.

You've already identified the problems with fillers, some don't wet sand, some don't adhere well, some crack or shrink, just a mix of issues.

If I find an area that needs to be filled, I mostly rely on plastic strip stock or sprue bits, shaped to best fill the area, then file and sand to finish. I only use the fillers to cure very minor spots, then either PPP or Tamiya white filler in the squeeze tube are my most used.

Larger gaps are best filled by plastic shaped to fit, since the join will be stronger than by using customary fillers, such as the wing to fuselage fit. As was mentioned cyano works well with no shrinkage, but comes with other issues of it's own.

I think the auto body fillers, (Bondo, etc,) are favoured by many modelers, since they don't seem to have the shrinking, cracking problems. I have used them and they do work well, but do require more work to finish by sanding or filing, since they do cure to a very hard end result.

Patrick

Its like what route62 said...depends on the need at the moment.

For general filling like seams or unwanted panel lines my favorite is Tamiya Putty.  It is solvent based and chemically melts into the plastic. It has very fine particles and can be wet sanded to a smooth finish.  Like all putties it will crack if you are too heavy handed rescribing panel lines in it but it can be scribed...just use a very light touch.

For things like 90 degree joints and ejector sink marks I love to use the Mr Surfacer/Mr Dissolved Putty line.  These are also solvent based and really grab onto the plastic.  And, as was mentioned earlier, excess can be wiped away with a cotton swab dipped in IPA.  There are different "thicknesses" depending on how big the gaps are.  Mr Surfacer 1000 is the finest, then 500, then the dissolved putty.  You can brush on the 1200 but it is best used as a primer with fine scratch filling ability.

For things like the gap between the windshield and the fuselage, for example, Perfect Plastic Putty works great (I think the Vallejo putty is similar)!  It can be applied to the gap and wiped away with a cotton swab dipped in water.  This won't ruin any paint or the clear finish on the canopy.

There are also the 2 part putties like Milliput and Aves Apoxie Sculpt.  These are sculptable and will dry rock hard.  Aves can also be wiped away with IPA while it is still soft.  I use Aves when I fill windows on airliner models or when I have some large hole or gap to fill.

Hope this helps!

I use Bondo spot putty. It comes in a tube and you can get it at Wal Mart in the auto section by regular bondo or at an auto store. It is a 1 part filler and a tube lasts a long time. It adheres well, applies like butter, dries fast, it's very fine, sands easily and does not crumble out. It is my go to putty. Its cheap too. I have no complaints.

I use Nitro Stan Red Putty. This is automotive putty. It is the best putty I have used (and I've tried them all....).

modelmaker66

I use Bondo spot putty. It comes in a tube and you can get it at Wal Mart in the auto section by regular bondo or at an auto store. It is a 1 part filler and a tube lasts a long time. It adheres well, applies like butter, dries fast, it's very fine, sands easily and does not crumble out. It is my go to putty. Its cheap too. I have no complaints.

 

Say Modelmaker... you got me interested to try this. The deal breaker for me would be the smell. I tried Bondo once and the smell nearly chased me out of the house. How bad of smell is the spot putty?

If it is still like it was 20+ years ago it is a laquer based putty, some may find it objectional. With the newer paints in the auto body trade it became obsolete for us techs in that trade.

goldhammer

If it is still like it was 20+ years ago it is a laquer based putty, some may find it objectional. With the newer paints in the auto body trade it became obsolete for us techs in that trade.

 

Kind of what I feared. Thanks for the input GH.

My .  I used to use the blue Bondo but can't get it in this area anymore so I switched to the red. One tube is very large but lasts a very long time. I put some of the putty in a small glass jar and add lacquer thinner to the consistency that I want. If the lacquer thinner in the bottle evaporates, just add more. I've had the tube I use now for the last 5 years and have only used a small portion of it. As was said above, it dries hard,  doesn't crack out easily and is fairly easy to sand (IMO) to a hard smooth surface.

Jim   

Yes there is odor but not very strong. Tamiya putty is worse. The squadron putty has a solvent odor. Any filler that holds is going to have some solvent propoty to it. That is why it stays put and dries hard. Anything that is no odor will be like what you already have used.

modelmaker66

Yes there is odor but not very strong. Tamiya putty is worse. The squadron putty has a solvent odor. Any filler that holds is going to have some solvent propoty to it. That is why it stays put and dries hard. Anything that is no odor will be like what you already have used.

 

Well--that is encouraging because I can tolerate Tamiya and Squadron. The two part bondo I had purchased was beyond anything that I could imagine. The smell permeated the entire house. I had to open windows and put the project in the garage to gas out. And that is too bad because in terms of use--it seemed to work pretty well. It was the best sanding filler I have used thus far. If I can find something like that, less the toxic smell, I'd be in good shape. Maybe I will try the putty. 

To get this thread back on track some: Tamiya is pretty good. It has a strong bond. The issue that I have with it boils down to sanding. I can feather it fairly well now, but, I struggled with pitting. Repeated applications did not get rid of it. I am guessing that the filler is not getting into those tiny pits. I am sure there is a way around this but I have not found it yet. Maybe others can shed some light.

Then there is CA. It works well but it can be tough to sand around any detail.

Another option is melted sprue. It has it's pluses. But--it tends to gas out from the solvent, and that causes divots. You need to apply a layer of something to fill those in.

My two cents to the subject. 

 

 

 

modelmaker66

Yes there is odor but not very strong. Tamiya putty is worse. The squadron putty has a solvent odor. Any filler that holds is going to have some solvent propoty to it. That is why it stays put and dries hard. Anything that is no odor will be like what you already have used.

 

Modelmaker... Letting you know that I have tried Bondo Spot Putty. I think I agree with you about the odor verses Tamiya. This is good news. The even better news is that it feathers very nicely with wet sanding. This stuff looks pretty promising to me.