Why do we Prime

Airborne01

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Which comes to mind... do some not prime being afraid of shoddy work showing up? :thinking: :smiling2:

Cheers,
Wabble
I only prime when I've integrated several contrasting or markedly different colours or materials. Otherwise I tend to just paint; if there's a marked difference in the end result I overpaint until the desired (or acceptable) result is achieved.
Steve
 

JR

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I always prime , it's a thing you do when you paint . Well it used to be but with some applications and modern paints it's not needed .
Now in our world I was told it would help adhesion of the following coats . I've found that if I didn't prime the paint would easily mark , scratch and generally not be able to with stand handling.
 

BarryW

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I've never primed my kits. I always thought 'prime' was a service from a rain forest company on the internet!!!

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Fair enough. But this is about why we prime, not about whether we do or not.

It would be more interesting if you told us why you decide not to prime and how you deal with the issues outlined instead of priming. I ask out of genuine interest.
 

AlanG

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It would be more interesting if you told us why you decide not to prime and how you deal with the issues outlined instead of priming. I ask out of genuine interest.
A. Because primer cost extra money that at the time i could not afford to buy it. When you count every single pound every week then it all adds up
B. Because i fill my seams and sand flush. Under a coat or two of paint they aren't that noticeable unless you get ultra close
C. I am not that anally retentive to worry about if i can see a seam line/mark from 2ft away. Which to be honest is probably as close as you get when they are on a shelf/display cabinet.
D. I've not really had a problem with paint adhering to my plastic. The only paint i had a problem with was Xtracrylix and i now haven't got any of them.
 

Allen Dewire

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To be honest Barry, over 90% of what I build is armor and soft skins. I have only recently gotten into building aircraft in 1/32. With armor, I may spray a red oxide undercoat but that's only as a basis for chipping and damage to the topcoat and camo. I am a person who washes his hands every time before I work on a kit. Sometimes 10 times a day, when I take a break to eat, shop and the like. With armor, you can always fix any small flaws that arise very easily without priming and weathering/mud is one of your best friends.

With my current Wingnut Wing's build, I may shoot a primer coat on the fuselage for the above stated reasons in this thread. The wings are one piece and I will paint those before applying the lozenge camo decals, but priming isn't necessary on them. When I get back to my 1/32 Arado 234 build, I think priming will be beneficial as it's a multi-media, short-run kit. Getting the wing root and fuselage joins smooth, by eye, won't be that easy. I'll have to wait and see though...

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BarryW

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A. Because primer cost extra money that at the time i could not afford to buy it. When you count every single pound every week then it all adds up
B. Because i fill my seams and sand flush. Under a coat or two of paint they aren't that noticeable unless you get ultra close
C. I am not that anally retentive to worry about if i can see a seam line/mark from 2ft away. Which to be honest is probably as close as you get when they are on a shelf/display cabinet.
D. I've not really had a problem with paint adhering to my plastic. The only paint i had a problem with was Xtracrylix and i now haven't got any of them.
I understand what you are saying. Of course for many people money is an issue.

As I build 1/32 mostly I find seams are much more visible and prominent and as much as you try to sort them first you cannot be sure until after the model is primed. No matter how much trouble I take primer always reveals a few flaws. I carry those habits over to 1/48 of late.

As I see it modelling is about attention to detail rather than being anal retentive. I am of the ‘if it looks right’ school of thought, but my eye is always drawn to seams and other flaws so then it ‘does not look right’.
Hence the high importance I pay to seams and priming. Not to mention. The shading issue of course.

Ultimately I suppose it depends on what we build and what we find important.
 

BarryW

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To be honest Barry, over 90% of what I build is armor and soft skins. I have only recently gotten into building aircraft in 1/32. With armor, I may spray a red oxide undercoat but that's only as a basis for chipping and damage to the topcoat and camo. I am a person who washes his hands every time before I work on a kit. Sometimes 10 times a day, when I take a break to eat, shop and the like. With armor, you can always fix any small flaws that arise very easily without priming and weathering/mud is one of your best friends.

With my current Wingnut Wing's build, I may shoot a primer coat on the fuselage for the above stated reasons in this thread. The wings are one piece and I will paint those before applying the lozenge camo decals, but priming isn't necessary on them. When I get back to my 1/32 Arado 234 build, I think priming will be beneficial as it's a multi-media, short-run kit. Getting the wing root and fuselage joins smooth, by eye, won't be that easy. I'll have to wait and see though...

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Yes, I see and it makes sense that armour is different to aircraft in this.

I think that you might find some primer helpful for those aircraft. I look forward to seeing that completed Wingnut build posted, it could be very impressive with that lozenge camo. I assume the AR 234 is the mainly resin kit? Not into resin myself and you are right, multi-media does benefit from priming.
 

Allen Dewire

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I assume the AR 234 is the mainly resin kit? Not into resin myself and you are right, multi-media does benefit from priming.
Actually Barry, the Fly Arado 234 kit's fuselage (in 2 sections) and wings are plastic. The cockpit and radar observer's pit are resin, along with engine internals. The wing's fit together really good, but the fuselage sections will need a bit of filling as well as the wing to fuselage joins. It's to be expected from a short-run kit.
I also hope the lozenge decals come out well and the rigging too!!!...

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David Lovell

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Oh well a simple question has turned into the usual Preachers v's Heathens ,I prime ,I prime because I want to not because my runner bean crop will fail as some of the Preachers would have me belive no it just gives me a nice solid background to work to ,if it helps others to see and correct faults in there work good im pleased but unless I've made a mighty bosh somewhere it can stay as it is I dont care I build for my own pleasure.
So the answer is its down to personal preference what ever you choose the modeling police won't bang on your door it won't affect the world you live in and if you feel its affecting what your trying to achieve you'll know what to do ,its called the learning curve.
Dave
 

JR

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Matron will be watching those of you who don't;):surprised::sad::confused: because it improves

1. Adhesion
2. Coverage
3. Self-Leveling
4. Durability, thats why.

Try not priming some surfaces and you will find out what its used.

Taxi please.

Good Afternoon .
 

Waspie

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Try not priming some surfaces and you will find out what its used.

Taxi please.

Good Afternoon .
And that is exactly what I will be doing in the next few days. Never primed before so it will be a learning curve for me.

Question regards seems after priming! How do you eradicate seem lines?
 
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BarryW

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And that is exactly what I will be doing in the next few days. Never primed before so it will be a learning curve for me.

Question regards seems after priming! How do you eradicate seem lines?

The processes I adopt are as follows:

1/ Before priming. Sand the seams with sanding sponges or sticks, using various grades of sander, working down to the finest grades. That ensures you get no scratches. Check the seam by looking along it under a light. If the are imperfections, then use a fine filler, I usually use Mr Dissolved Putty as it has excellent self levelling properties so the solid material ‘sinks’ into even the tiniest imperfection, leave it to cure for a good few hours. Sand again, working down through the sanding grades. You might want to start this at a finer level than the first stage.

I do this on every subassembly, I might have several of these subassemblies to pull together before priming as the seams between subassemblies might also need treatment.

2/ After priming. Examine the model closely. Look for any glue or other flaws shown up by the primer, check the seams, as before, looking along the seam under a light. Make no mistake, no matter how carefully you looked before priming there will still be imperfections showing. What are called ‘ghost seams’ are common. The reason for that stage 1 is to get the ‘basic’ heavy lifting done before priming and reduce the effort after priming. Take it for granted that every seam will need treating.

You are likely to see points or areas that need more treatment. I tend to use small pieces of masking tape to mark these areas. I then use Mr Dissolved Putty on those areas followed by sanding again through the grades. Then reprime and check again, repeat if necessary.

After your final reprime, check the engraved detail and rescribe such as panel lines and rivets where is has been sanded away. Check YouTube for help on this, it can be tricky to do but is well worth the effort.

Note, it might be worth, on some models, to lay masking tape each side of a seam to limit the damage to the engraved detail and reduce the amount of rescribing you need to do.

Finally get a polishing sponge and run it all over the primed surface to ensure it is nice and smooth ready to take a base coat.

I hope that helps.
 

Tim Marlow

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The processes I adopt are as follows:

1/ Before priming. Sand the seams with sanding sponges or sticks, using various grades of sander, working down to the finest grades. That ensures you get no scratches. Check the seam by looking along it under a light. If the are imperfections, then use a fine filler, I usually use Mr Dissolved Putty as it has excellent self levelling properties so the solid material ‘sinks’ into even the tiniest imperfection, leave it to cure for a good few hours. Sand again, working down through the sanding grades. You might want to start this at a finer level than the first stage.

I do this on every subassembly, I might have several of these subassemblies to pull together before priming as the seams between subassemblies might also need treatment.

2/ After priming. Examine the model closely. Look for any glue or other flaws shown up by the primer, check the seams, as before, looking along the seam under a light. Make no mistake, no matter how carefully you looked before priming there will still be imperfections showing. What are called ‘ghost seams’ are common. The reason for that stage 1 is to get the ‘basic’ heavy lifting done before priming and reduce the effort after priming. Take it for granted that every seam will need treating.

You are likely to see points or areas that need more treatment. I tend to use small pieces of masking tape to mark these areas. I then use Mr Dissolved Putty on those areas followed by sanding again through the grades. Then reprime and check again, repeat if necessary.

After your final reprime, check the engraved detail and rescribe such as panel lines and rivets where is has been sanded away. Check YouTube for help on this, it can be tricky to do but is well worth the effort.

Note, it might be worth, on some models, to lay masking tape each side of a seam to limit the damage to the engraved detail and reduce the amount of rescribing you need to do.

Finally get a polishing sponge and run it all over the primed surface to ensure it is nice and smooth ready to take a base coat.

I hope that helps.
Very sound advice Barry. Regarding rescribing seams lost during sanding, I’ve found it useful to rescribe the existing detail deeper as it gets eroded, and before it disappears. That way you are not rescribing completely from scratch.
 
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