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First Spray gun?

22K views 227 replies 15 participants last post by  carolinacustoms 
#1 ·
Hi

I am completely new to the idea of spray painting. I was looking to paint a few panels on my car. To be specific the fenders and the bumper.

I have been reading a lot about compressors and spray guns but I am having a difficult time making a final decision. I was wondering if someone could help.

My two disadvantages are compressor size and budget. I have a 11 gallon compressor rated at 5.5 cfm @ 40 psi and 4.6 cfm @ 90 psi.

I was wondering if someone could suggest a small spray gun for the job that would work with the compressor. I plan on doing one panel at a time so I am not too worried about compressor size being big enough to do all panels in one.

Also I am not looking to get something too high quality, something mid range. Thanks in advance.
 
#61 ·
I can't get the pictures to load, but I will offer this bit of advice that may help you when sanding. Apply just enough pressure to the block to hold it to the panel, not very much at all. When sanding, try to imagine an "X" on the panel and sand at angles. Sand this way / for a while and then, sand this way \ for a while and keep switching between the two angles. That will help avoid creating lines and will also keep curved surfaces curved and prevents forming little ridges on the curved top of the fenders and other areas. If you are going to be wet sanding, I would recommend getting a squeege (sp?). You can buy several different types. I have one that came from my paint jobber that I gave in the $25 range, but I found some at "dollar tree" for $1 that work just as well, they just don't last an extremely long time, usually trash one per car, but for $1......... The squeege will let you periodically dry the panel quickly to see what you have done and what needs to be done to make sure you are getting an even surface.

Bulk Scrub Buddies Window Squeegees, 10" at DollarTree.com

I don't know if dollar tree is nationwide or not?


Kelly
 
#62 ·
I can't load the pictures...I'm in the house again with that computer that likes to act up...I'll be in the shop in the morning, the computer works better there...and I'll give you a game plan. Don't worry, unless you sanded through the metal and made a hole we can easily fix whatever didn't seem to go to well today....and the next fender will be easier...I promise.

Ray
 
#63 ·
Kelly's advice is sound...just like we discussed in post # 55, the reason you are getting the sanding lines is, as I mentioned, the sanding motion was in a straight line and I know it's difficult not to put pressure on the sand paper, but the results will be much smoother and straighter when you let the sand paper do the work.

Thanks Kelly, I appreciate the affirmation...even if it's subliminal, reinforcement of a proper procedure often helps when someone is learning...now when he sands the next fender...I bet he's going to be thinking that it must be true because 2 guys said it.

Ray
 
#64 ·
Yeah I think it is because I uploaded through a mobile device. Here is the link again. This should work fine.

https://www.dropbox.com/sh/4tivtsfzth3ekez/PGbuwqiVAQ

Again the scratches will be obvious. I feel like the areas I had trouble with were where there were curves. The very outsides where the panel is mostly flat seemed to have gone good.

Thanks for the advice it is always helpful to hear again. Take a look at he pictures and let me know what you think and how to proceed. If you need additional pictures just let me know. Once again thanks a lot!
 
#65 ·
I still can't load the pictures...I get the site and a Gray outline of how many pictures there are but no pictures.

Well, it might be a good idea to remedy the situation. Do you have any coarse paper, like 80 grit or 180 grit. You mentioned that you had some bare metal spots showing through, I can't see how large or how small they are but, it's never a good idea to paint over bare metal. What we can do is scuff the fender by hand (the palm of your ) with 180 grit...don't worry about the sanding lines from yesterday. You have never painted before and your going to need some practice, you have 2 sprayable quarts of Epoxy Primer coming and we will apply 2 medium wet coats of Epoxy Primer over the fender. This will give you some practice, it will help in removing the sanding lines and the fender gets more protection.

What you could do today (or when ever) is take your Gray Scotch Brite pad and scuff the inside of the fender....(yes it will be getting a little bit of color as well).

When you go to sand the next fender take every precaution to sand as Kelly described and how I mentioned in post 55...this will eliminate the lines and it works well, especially on curves.

It would still be nice to see pictures...they always help.

Ray
 
#66 ·
Okay I tried something different with the pictures. Try this link now and let me know.

https://www.dropbox.com/sh/qvllt5nshbkl5qy/xOleI_HXXv

I can get the 180 or 80 grit sand paper for the fender. When I am scuffing the fender by hand I should still follow the same precautions you and Kelly mentioned? As to not put too much pressure and sand at angles instead of straight lines. And should I get the guide coat for the 80 or 180 grit also?

Also when scuffing the inside of the fender with gray pads do the same precautions apply or would I need to apply pressure when using the pad?

Thanks and hopefully the pictures load this time. If not I can try to come up with a different solution.
 
#67 ·
I was able to load the pictures...thank you...yesterdays efforts where not a waste of time...you now have learned from experience how delicate the sanding procedure can be...and experience is a very good teacher.

When sanding, it's always a good idea to let the paper do the work...doesn't matter what grit. The minute you apply excessive pressure you will distort the substrate (E coat) and shape of what your sanding. This is most important when working to achieve an automotive finish, unlike sanding dry wall where paint covers most anything and the low gloss and Orange Peel finish of house paint will hide a great number of sins...not so on cars, every imperfection will so in the finished product....especially dark colors and metallic's. Always sand in an X motion...this will remove all those sanding lines quicker from yesterday and keep the curves in your fender looking like curves.
With a Gray Scotch Brite Pad, the pad will act as a cushion and not distort the E-coat...also, it's the inside, all we want to do is get some color on it and a little more protection from the elements.

Seeing that you have sanding lines and it will take forever to get them out with 600 grit, lets resign ourselves to the fact that we are going to apply some Epoxy primer over top of the E-coat that you will have remaining on the fender. Get some 180 grit dry sand paper and using the palm of your hand, go over the outside of the fender...in the hard to reach areas, use the Scotch Brite pad. No or little pressure on the paper...this will go quickly and when it comes time to apply the Epoxy primer, we will use guide coat to make sure that the fenders are straight...today there is no point in using guide coat...we are just roughing up the panel for Epoxy primer.

Ray
 
#70 ·
I look forward to it...this is going to be a good learning experience and I always try and find the positive in any situation...to recap what you've learned so far.

1) Sand in a X or cross hatch motion...this keeps the curve in the curve and the rest of the panel straight.
2) Don't apply pressure on a sanding block or sand paper, let the paper do the work.
3) If you make a mistake sanding, it can be repaired and in this case, your fender will be getting more corrosion protection than it had from the manufacturer and the coating you are putting on will be easier to sand...that's a positive from a mistake.
4) Patience is a key personality trait to have...this part of the repair is tedious.
5) Sanding is a PITA...and anything you can do to make your sanding life easier will be done...LOL.
6) Your going to be getting more time behind the spray gun before applying color and clear...that's a good thing...experience is the best teacher...again, another positive from an error.
7) This is harder and more work than you originally thought...now you are starting to understand why it cost so much to paint a car...LOL

There are more things I'm sure...but our goal in the end is to have a vehicle repair done that isn't noticeable...there is a lot more learning to do...LOL...we'll get there.

Ray
 
#72 ·
Sometimes it's just a good idea to go over things and reassure that things haven't been a waste of time...I know sometimes I've gotten a little depressed (kinda like now...trying to figure out the electrical system on my Wife's car...more wires that don't appear to have a purpose than mosquito's at a nudest colony...wait, they would have purpose...LOL) but, I know when I figure it out...that blower motor is going to work without replacing every module, motor, relay or whatever. I will find the culprit and fix what is necessary...and in that there is satisfaction.

You will do better, you now know more.

Ray
 
#75 ·
Sounds great my friend, remember, tonight when you sand, let the paper do the work, sand in a X pattern, 5 strokes or so in ///this direction, another 5 strokes or so in \\\ this direction...no fingers, just the palm of your hand. You can and should be a little more aggressive with the Scotch Brite pad in the hard to reach areas...and use the Scotch Brite on the inside of the panel.

When you called SPI, did you mention my name? Not that it would help unless you wanted to use the washroom, then they might offer you a good seat...LOL

Ray
 
#76 ·
I did not mention your name but now I know it will come handy in an emergency bathroom situation LOL!

I will keep all of the precautions in mind. When I am sanding with my hand, am I just cutting the sanding paper and using my palm or is there something that you buy that holds the paper and you put your palm on that?
 
#77 ·
That's a very good question...what I've done for new students that had a tendency to finger sand (some just gotta use their fingers...don't know why but) at a college I was instructing at was to have them place the Scotch Brite pad in their hand between their palm and the sand paper. I don't know if anyone has ever tried this in a classroom situation before but, this did have good results and usually after several hours of sanding this way, it became a habit and the need for finger sanding went a way.

Hope this helps.

Ray
 
#78 ·
I am almost done with the sanding. Maybe another hour or so and then I can upload some pictures of the progress.

Before I do that I wanted to ask that when I am done with the sanding and scuffing, should I wash the panel off and then take some pictures?
 
#80 ·
Actually I did not use the scotch brite pad. It was getting a little difficult to get a grip to maintain the X motions. So I tried without it but it was still a little difficult. However, after a little while I got the hang of it. I believe I did much better this time but you can be the judge of that when I upload the pics.

I just have to scuff the inside, clean and then pic time!
 
#82 ·
No problem. Sleeping is one of my favorite past times!

Anyways I got 180 grit sanding paper. Started dry sanding. Tried to follow the precautions the best I could.
I have uploaded the pictures. Here is the link:
https://www.dropbox.com/sh/jjbs1uzqs7vsgtv/vu3qDpMV8U

Let me know what you think. If you think it needs to be sanded more or whatever your opinion is. I also took pictures of the inside. I just did a rough scuffing. Let me know if you think more scuffing needs to be done. Also let me know if the pictures are not clear or you need more to be able to judge better.

Thanks!
 
#83 ·
That does look much better...before we prime the fender, take the scotch brite pad and go over it quickly one more time...just to be sure that there aren't any shiny spots left on the fender...but, the way it looks now...you get a gold star.

Good job, when are you going to dig into that bumper.

ray
 
#84 ·
Great! My hand got so tired sanding it. Task after task I appreciate auto body shops more.

Okay I will go over the fender with scotch brite pad again. Should I go over the whole fender or just the inside?

I plan on digging into the bumper tomorrow. When I am using the red scotch brite pad on the bumper, do I need to follow the same precautions as I did for sanding or is the purpose to just rough it up and get the substrate off?
 
#85 ·
What I like to do and it's probably more of good luck thing, like in Hockey where player's don't shave in the playoffs, football they bump helmets after a good play, high fiving the wife for being tolerant of your bad habits and table manners...just before I apply the primer, I give it a going over...take another look at it to make sure that all spots have been sanded....and it opens the E coat up again...I'm sure it's just superstition but...it's never a bad idea to go over your work...several times I've found that small area that I had missed before.

The purpose of sanding the bumper with detergent is to get the mold release off and to gently rough up the plastic for the Epoxy primer. Concentrated more on the outside, we won't be applying much paint to the inside, it's rubber/plastic and won't rust. The Scotch Brite will seem to not dig in on the plastic as well as it did on the E coat, that's Okay, just make sure that all areas are scuffed.

Yes, the respect you are gaining for the body shop guy...and I've always been amazed at how in this trade, the most important job, prepping and sanding, is usually given to the guy with the least amount of experience. Good preppers are worth their weight in Gold...and real hard to find...I always tried to show the preppers I had the utmost of respect...a good prepper can make a bad painter look good, but, a good painter can't make a bad prepper look good.

Ray
 
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