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Self Etching Primer

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Hello guys,

 

I am new to these forums, but I have a new fascination with case modding as a direct result of Bill et al and the wonderful guides that are so graciously provided.  I have a question about SEM self-etching primer, as I have noticed that it is the brand of choice for nearly all of the painting guides that are on the site-

 

I live in New Orleans, LA, and SEM Self-Etching Primer is not sold at any of the autobody stores around here... or any other store for that matter.  I have been ordering it off of Amazon, but I find the wait-time to be tedious and it can really hinder my ability to complete builds in a timely fashion if I run out.  Apparently due to the toxicity of the SEM Primer it cannot be delivered via airmail and so is not eligible for Amazon Prime.  In addition to the inconvenience of obtaining the product, the price is steep and I find that the paint spray becomes inconsistent at around 25% full.

 

My question is this:  Is it necessary to use the aforementioned self-etching primer, or will any brand do.  I went to Autozone and purchased some Rustoleum Self-etching primer to give it a try, and although I have only applied a coat so far (a few minutes ago) it seems to provide even coverage and lays as flat as SEM.  So before I waste my plastikote metal flake paint (also hard to come by), is there a major difference between the SEM self-etching primer and other brands?  If not using SEM brand will result in a degradation of the final product, then I will just start ordering it in bulk; however, if it is just a brand-loyalty issue or a spray output affinity then I will switch over to the more convenient Rustoleum product.

 

Finally, does it matter what color the self-etching primer is when used in conjunction with a metallic or metal flake color (such as plastikote blue metal flake)... will the primer color affect the outcome of the paint color?

 

Thanks so much for any info on this,

 

Carson Riess

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Look in your area for Auto paint suppliers and start calling around. Most will carry it in stock.

CarQuest around here sells paint and they also have it.

 

Primer color can effect top coat to some extent ,but generally for our purpose and enough coverage it would have no effect.

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Yes, it's a bitch to get.

 

To answer your questions...

*No Aerosol can paint will give you consistent spray after it's can pressure has dropped below 25%. It's the compromise you make in using aerosol paint over air compressor and spray gun.

 

*When choosing base coat color, match the shade to your top coat color,

 

Grey Primer = Light Colors, White, Sky Blue, Silver etc

Red Primer = Brown, Orange, Red,  

Black Primer = Any Dark colors like Blue, Charcoal Grey etc

 

Why is SEM is expensive, harmful, and hard to find?

 

Because SEM Primer is manufactured for "professional use" in a commercial/industrial environment where proper safety precautions are to OSHA standards, and the applicator is wearing a properly filtered respirator mask. Majority of Retail consumers won't abide or have these same type of precautions at home.

Why buy SEM over "retail consumer grade" paints?

1. Adheres equally well on all Plastics, Aluminum, and Steel surfaces
2. Applies won;t run unless you're
3. Dries Quick, ready for topcoat in 60 minutes, in recommended environment
4. Very Durable, can also be used as Final Color Coat
5. Reliable "Non Leak" Spray Nozzle

6. Compatible with most retail brand paints as topcoat

If consumer brand like Rustoleum offered those same benefits as basecoat, before using any aerosol paint as color top, I would recommend that product. It doesn't mean you can't experiment and decide what product(s)are best for you  :) 

Welcome to the Mod Zoo!  and I look forward to watching your project unfold here, please feel free to ask any of us more questions.

 

wolfensteincasemod.casemodblog9z9z9n.jpg











 

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@ Primal, we're lucky, we have Auto Plus, (formally Red Rooster) in Minnesota, it's the single best local source for 3M supplies, SEM and Plastikote brand paints in the entire state.

 

  •  
  • Address: 8810 Lyndale Ave S, Bloomington, MN 55420
    Phone:(952) 888-4321

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 Hey Bill,

 

Thanks for the info...  I've watched quite a few of your tutorials, and I hold your advice in high regard.

 

 

*No Aerosol can paint will give you consistent spray after it's can pressure has dropped below 25%. It's the compromise you make in using aerosol paint over air compressor and spray gun.

 

I do realize this, but the SEM self-etch primer can that I have seemed to feces out a good deal before other rattle cans that I have (with the exception of things like sealers and enamel).  This is probably due to my having waited for a while between projects, as well as my not having cleaned the nozzle out.  I have since invested in a ~6$ 3m brand aerosol can trigger (like this http://www.autozone.com/autozone/accessories/3M-Aerosol-paint-can-trigger/_/N-255s?itemIdentifier=557066), and I have not had as many issues with consistent spray due to angled application... BTW - this is a cheap tool that might be of interest on the 'Suggestions for PC & Case Mod Tools' thread.

 

 

 

1. Adheres equally well on all Plastics, Aluminum, and Steel surfaces

 

I wondered about this, as you wrote in your 'DIY PC Mod Guide: Paint PC case with Mirror-like finish' thread that for plastics it is necessary to get a flexible primer (I believe you recommended plastikote flexible filler/primer).  I also read that there are abrasive chemicals in SEM self-etching primer that are not good to use on plastic; however, I painted a plastic front bezel on a case before having read that and the SEM primer did a wonderful job.

 

 

 

please feel free to ask any of us more questions

 

Don't mind if I do! :D   I have two questions for you:

 

1) When using a self-etching primer, is it advised to lightly wetsand it with a high grit paper in order to create an initial smooth layer?  I ask this because I have read and watched guides on both automotive and pc case painting and they almost all advise this.  Given that one should not wetsand metal flake paint, I was thinking that a smooth initial surface is of even more importance.  If you do advise that self-etch primer be wetsanded prior to metal flake application, what grit do you think would be ideal?  The guides I have read suggest 600, but that seems a bit coarse to me.  I was thinking something like 1000 grit wetsanding.

 

2)  I have had the hardest time of all with the clear enamel step of the 'DIY Mod Guide: Painting Anodized Aluminum PC Case' guide.  I imagine that this is a tricky step for most noobs like me, but I wonder if you have any suggestions to minimize spotty distribution.  I know that the orange peel effect doesn't show until the enamel has cured, but it seems like from the get-go there are shiny spots when the light hits the painted piece from an angle.  I have read that letting the clear engine enamel sit in a bucket of warm water prior to application will help with this, so I have mine sitting outside right now (New Orleans has a warm climate  to say the least).  To tie this question  into my first one, I have also read that how smooth each layer of primer/paint is prior to the topcoat has a huge effect on how easy it is to apply a clear finish.  Anyway, do you have any tricks/hints that might help with the even application of clear enamel?  I have all of the tools to fix a spotty coat (800, 1000, 1500, 2000 grit wet/dry paper; sanding block; rubbing compund and polish), but I have never fixed a topcoat layer and it seems like a pain in the ***.

 

Thanks so much for any advice you can give... and I am writing this to all forum members who might be able to help.  I am thankful for all instructions & opinions -- even if incorrect. ;)

 

-Carson

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Oh, I forgot to mention that I was able to locate some SEM self-etching black primer at CarQuest here in New Orleans.  Just thought I would follow up on that.

 

-Carson

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Well, I can say unequivocally that SEM Self-etching primer is well worth the price, wait, respiratory issues... whatever. It is so far superior to the a rustoleum brand that I am amazed they sell the latter without being reported to the BBB. I had one interior chassis component primed with SEM, while the rest were primed with the feces primer... it was a struggle to even set the other pieces down to dry without immediately chipping the primer, while I think I could've chucked the SEM piece down a flight of stairs without a scuff.

For those who are interested: listen to Bill and go with SEM... You will regret not doing so. I'm off to cry:(.

-Carson

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If you ever decide to try using a spraygun, I can't recommend the House of Kolor KD3000 series enough. 5 primary colors, mix and match your base of choice, and they do a silver sealer for metallics. Big investment though to go that route.

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If you ever decide to try using a spraygun, I can't recommend the House of Kolor KD3000 series enough. 5 primary colors, mix and match your base of choice, and they do a silver sealer for metallics. Big investment though to go that route.

+1

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If you ever decide to try using a spraygun, I can't recommend the House of Kolor KD3000 series enough. 5 primary colors, mix and match your base of choice, and they do a silver sealer for metallics. Big investment though to go that route.

Thanks for the suggestion. I am familiar with the brand because Bill had a thread in which he showed the red candy apple color, and I looked into it as it would match my build perfectly... but you're right, it is expensive stuff.i didn't look at their spray gun, but I'll check it out tonight.

-Carson

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After looking up the item I now realize that kd3000 is a primer not a spray gun. Is this a self-etching primer? What is superior about it? I mean, is it just that it is spray gun compatible, or does it have advantages over the SEM primer?

Also, does anyone have any suggestions on a spray gun that won't break the bank. I know they are all expensive relative to rattle cans, but is there a one that is adequate for small products like computer modding?

Thanks,

Carson

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Here is good place to look around. 1 qt kit.

 

As far as spray gun you could get away with a harbor freight full size gun to use for primer. They will get you through the job but they won't last long. You may need some reducer for the primer to get it through the smaller nozzle (1.8 recommended). The little gun will work for finish.

 

Catalyzed primers dry rock hard ,don't shrink and stick like no tomorrow,but gun has to be cleaned very thoroughly if you ever plan to reuse it. Plan on 1/2 gallon lacquer thinner to clean it each time. Don't forget respirator ....over-spray will also stick to everything it lands on.

Good primer gun can set you back $400 and top of the line clear coat gun near $800+ for SATA digital.

I could go on and on.

 

I would look at it like this: It's a PC,it's wont see rough handling or harsh outdoor environments. Stick with SEM.

 

Here is a case I painted with Duplicolor for someone. Not a big fan of rattle cans...but good finish can be obtained. I used non-sanding primer sealer and went straight to paint. Took me long time to find these pics I did this many years ago. These were taken 4-5 hrs after it was painted. 

give2082.jpg

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I got a decent finish with clear coat enamel my first go at it. I soaked the can in a bucket of warm water for 5-10 min to help it flow. I did 3-4 light coats, I feel like 5-6 would have been ideal. I didnt get any orange peel, I think this is due to the light coating. Make sure the painted surface is clean before you start, and take your time. I didn't do any sanding on my primed surfaces either, just many light coats to start with.

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noobas4urus:

 

Thanks for the reply.  I also managed to achieve an even clear coat this time by leaving my cans outside until I was ready to use them.  I also stopped spraying when I got near 25% full! because I find this causes it to spatter out unevenly.  So yea, it seems warmth, technique and patience is what I was missing.  I also happened to have taken more time cleaning with tack clothes and isopropyl alcohol after each quote... huge difference.

 

FannBlade:

 

Thanks again for the info.  Great suggestion on the gun, but I had to make sure it read it correctly when you said a 1/2 gallon of lacquer thinner each time! I think that in the end you are right about the nature of chassis painting: it's not subject to that much wear and tear, so rattle cans -- although not optimal and frustrating at times -- are sufficient if used correctly.

 

For those who are interested, I think my final product came out nicely (built for a customer that I knew, so I was willing to chance it with the rustoleum primer):

 

i linked to to the pictures cause I can't seem to upload from an iPad. I think the link is at the top. If it doesn't work I'll hit my desktop and upload some pics of the final results.

 

 

 

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Oh, I forgot to mention that I managed to build this for an amazing price:  it's supposed to be a budget build, and for these I always use AMD APU's, as I think they give an incredible bang for your buck if you don't need gaming or video rendering.

 

The specs are:

 

Case: Corsair Spec-03 White

MB: ASUS f2a85-m Pro

APU: A8-5600k

RAM: Kingston Hyper-ex 2x4GB @ 1600xmp

PSU: Corsair CXM-430

SSD: Intel 520 120GB

HDD: An old Seagate 350GB I had laying around

Cooling: 2x Corsair af120 LED edition Blue; CoolerMaster super cheap closed loop waterbock

Lighting: Logysis sunlight stick (white)

Painting: y'all know this already!

 

Price: less than $400.00

 

I'd love to get your options on the paint job.  Taping off the front bezel was the hardest part by far, and I ended up going out and getting automotive quality masking tape.  I didn't charge for labor since I was building for a friend, although he insisted he pay me something so I took a carton of smokes and enough money to buy some SEM self-etching primer!!!  :D

 

-Carson

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That looks good! Nice job on the two tone lines. 

Thanks!  As I mentioned, the front was the hardest to get straight lines on.  It took me a second go-round due to underspray (blurred lines).

 

-Carson

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I am in the process of painting some clear acrylic, but not all of the acrylic is to be painted. I used the SEM self etching primer, as I find that it lays flat and applies more seamlessly than plastic primer followed by a colored top coat. I also find the black color of the etching primer to be spot on for my purposes.

Bill listed its usefulness as a topcoat as one of the benefits of this product, but I wondered if anyone could suggest a good protective sealer/clear coat that will apply safely to both the painted and unpainted part if the acrylic, and that won't affect the appearance. For example, I considered using clear enamel, but I worry that it might affect the translucency of the clear part of the acrylic. I also found on another piece that enamel ... when not applied globally ... lays with a noticeable shell, so to speak. In other words, I'm looking for a protective sealer that will lay flat and have minimal impact on the appearance of the piece.

I hope that I've made my inquiry clear, but it can post some pictures if I need to.

Thanks,

Carson

PS: the piece I'm painting will be inside the chassis and not handled too much, so it doesn't need exceedingly strong protection. It just needs to be sealed such that minor handling or an accidental coolant leak won't chip or blemish the primer-painted part of the acrylic.

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You could try FLAT enamel clear over a SEM painted TEST piece first. It will likely change the shade of the Black, but maybe slightly?

Aad clear coat will effect the clarity of the piece, but the change may be minimal

Experimenting with scrap pieces will answer a lot of these concerns.

Please share your project in the Member work logs, it sounds very interesting!

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