Building Before Paint?

[1hobby1]

Hi Everyone, 

I've had a couple kits I completed recently (and am working on currently) that had some fitment issues that I only realized after the parts or even the body, were painted. Even painting the body, assembling the chassis all painted and compete just to find out, something is warped when bringing the two together. It was quite frustrating and I was looking for a way to help avoid this in the future.

My question here is: Do you typically build the kit entirely with an Elmers glue or something similar, without paint to get all fitment issues sorted and then tear it down, paint all the parts, and re-assemble? What are some ways you have avoided fitment issues after parts have been painted? Any insight, tips or tricks here would be great. Thanks in advance!

-Steve

[StevenGuthmiller]

You don’t need to assemble the entire kit, but it’s almost a requirement to test fit, and test fit often.

Check tolerances between parts, such as between the body and hood and be certain that you have ample space to allow for paint thickness.

If the bare plastic parts fit tight, it’s too tight.

The type of paint and the number of coats is a big factor as well.

If you’re using thick paints, such as enamel, or multiple coats, regardless of the paint type, you need to allow more space.

 

 

 

Steve

[Bainford]

4 hours ago, 1hobby1 said:

My question here is: Do you typically build the kit entirely with an Elmers glue or something similar, without paint to get all fitment issues sorted

Yup, that's exactly what you do. It is referred to as 'doing a mock-up' and as Steve eluded, it is pretty much necessary to ensure you find and sort fit issues before paint, etc. The first thing I do after dumping the parts out onto the bench is mock it up to check for any problems and warped parts. I build it up enough to get the wheels on and check the stance and note any corrections needed. Numerous mock-ups will be done throughout the build to check for any arising issues. This includes mocking up sub-assemblies such as the engine , interior, etc, to check fit before painting. Most kits will have some sort of fit issue somewhere, often significant, that needs to be sorted before paint. Mocking up is especially important if you are making any modifications from the original kit, swapping parts, or using any aftermarket parts, etc.

[1hobby1]

3 hours ago, StevenGuthmiller said:

You don’t need to assemble the entire kit, but it’s almost a requirement to test fit, and test fit often.

Check tolerances between parts, such as between the body and hood and be certain that you have ample space to allow for paint thickness.

If the bare plastic parts fit tight, it’s too tight.

The type of paint and the number of coats is a big factor as well.

If you’re using thick paints, such as enamel, or multiple coats, regardless of the paint type, you need to allow more space.

 

 

 

Steve

 

2 minutes ago, Bainford said:

Yup, that's exactly what you do. It is referred to as 'doing a mock-up' and as Steve eluded, it is pretty much necessary to ensure you find and sort fit issues before paint, etc. The first thing I do after dumping the parts out onto the bench is mock it up to check for any problems and warped parts. I build it up enough to get the wheels on and check the stance and note any corrections needed. Numerous mock-ups will be done throughout the build to check for any arising issues. This includes mocking up sub-assemblies such as the engine , interior, etc, to check fit before painting. Most kits will have some sort of fit issue somewhere, often significant, that needs to be sorted before paint. Mocking up is especially important if you are making any modifications from the original kit, swapping parts, or using any aftermarket parts, etc.

Awesome. Thank you guys for the insight. I do test fit parts but a full blown mock up is what I think I need to be doing to get some models where I’d like them to be. I’ll give that a shot on my next build. Unfortunately, a little too far into the one currently on the bench to do that LOL. 

[StevenGuthmiller]

29 minutes ago, 1hobby1 said:

 

Awesome. Thank you guys for the insight. I do test fit parts but a full blown mock up is what I think I need to be doing to get some models where I’d like them to be. I’ll give that a shot on my next build. Unfortunately, a little too far into the one currently on the bench to do that LOL. 

While mock-ups certainly have value depending upon what your goals are, and they’re absolutely crucial when doing major modifications and parts swapping, they will help you little with items such as I stated with hood fitment.

The hood may fit perfectly fine prior to paint, (and this philosophy can apply to many assemblies) but after paint, it could very possibly fit very poorly.

Mock-ups and subsequent modifications are often required for many assemblies such as engine or chassis fit, etc, but in some circumstances, good old fashioned forethought and planning are the name of the game.

In some of my recent builds, I’ve used old annual kit bodies with sometimes heavily modified substituted engine, engine bay, chassis and interior parts from other kits, and by doing those kinds of builds I’ve realized that everything, and I mean every tiny aspect of the project, has to be intensely scrutinized over and over again to insure proper fit long before any painting is even considered.

Of course, when building basically out of box, this high attention is not quite as important, but it’s certainly a good idea to use the same type of scrutiny just to be certain that everything is going to go as planned.

The idea of thinking of every sub-assembly as a separate model can help considerably as well, but determining how those sub-assemblies correspond with each other is the real trick.

 

 

 

 

Steve

[Bucky]

If you go as far as mocking up the body, interior, and chassis to check for close tolerances, be sure to add the windows to the mock up.  Sometimes, the thickness of the windows along the bottom can really mess with the fitment of everything else. 

[Ace-Garageguy]

On 8/6/2024 at 5:44 PM, 1hobby1 said:

Do you typically build the kit entirely with an Elmers glue or something similar, without paint to get all fitment issues sorted and then tear it down, paint all the parts, and re-assemble?

Yes.

Which is the same process, essentially, as building a real car (not the factory, but building customs, rods, restorations, etc.)

Edited August 7, 2024 by Ace-Garageguy
TYPO

[slusher]

I have never built before paint. I test fit as I build..

[bobss396]

This is why I "pin" almost everything as I go along. I have to make up location blocks, pin sub-assemblies with plastic, brass or whatever I have around. The interior, body and of course glass have to go back together the same exact way. 

Glass is always the wild-card and deserves a lot of attention. Sometimes it will interfere with the dash and interior tub. I have cut the joining strips off them too. 

[Pierre Rivard]

I don't use Elmers glue but I dry test everything multiple times and always a mock up of the chassis to set the ride height to where I want it.

Also important (to me) is having a good painting strategy. Some parts need to be cleaned off, deflashed and painted individually and some can be pre-assembled and painted together as a subsystem. 

A lot of time is spent on a project before cement and paint steps start.

[bobthehobbyguy]

 

Another useful tip when using parts from different sources is to pin parts so that will always go together there same way. Also a good habit when part placement can be vague.

[StevenGuthmiller]

4 hours ago, bobss396 said:

Glass is always the wild-card and deserves a lot of attention. Sometimes it will interfere with the dash and interior tub. I have cut the joining strips off them too. 

This is why I've begun resorting to replacing kit glass with very thin, (.007) clear lay film whenever possible.

Not only does it virtually eliminate any fitment issues, but it also addresses the usual "way too thick", "distortion" appearance issues.

Is it a little more work?

Certainly.

But in my opinion it's well worth the extra effort.

 

 

 

Steve

[StevenGuthmiller]

4 hours ago, Pierre Rivard said:

I don't use Elmers glue but I dry test everything multiple times and always a mock up of the chassis to set the ride height to where I want it.

Also important (to me) is having a good painting strategy. Some parts need to be cleaned off, deflashed and painted individually and some can be pre-assembled and painted together as a subsystem. 

A lot of time is spent on a project before cement and paint steps start.

100%

 

 

 

Steve

[1hobby1]

Thank you all for the advice. This is all super valuable information. I typically build more box stock style models but I’m going to implant these processes into my builds. I do have a project in mind that is going to be more on the full custom side so all these answers will help tremendously. 

[bobthehobbyguy]

Another thing is when you pick a kit to build ask here what issues others have run into with that kit.

[1hobby1]

1 hour ago, bobthehobbyguy said:

Another thing is when you pick a kit to build ask here what issues others have run into with that kit.

Great idea. Thank you for sharing that video. Not sure how I have not stumbled upon that YouTube channel before but man there is some great information on that page. 

 

[bobthehobbyguy]

Here is another great  Channel.

First of a series of v building the amt 50 Ford convertible.

 

[1hobby1]

28 minutes ago, bobthehobbyguy said:

Here is another great  Channel.

First of a series of v building the amt 50 Ford convertible.

 

Yes, I agree. SME is a great channel. I’ll give this episode a watch. Thanks!

[slusher]

11 hours ago, bobthehobbyguy said:

Here is another great  Channel.

First of a series of v building the amt 50 Ford convertible.
 

 

Thanks for the videos Bob!

[bobss396]

We had an older guy in the club, who is no longer with us. He had the habit of painting himself into a corner with his builds. Things would come up VERY late into his builds. He would paint bodies right away and put them away for final assembly.

Another was a car that had a glass canopy. He was into the late-build stage and had no way to locate the glass. We tried to give him some ideas, I'm not sure if it was ever completed.