How To Respray A Car – Part Six – Guide Coat

Although this step is not absolutely necessary, it is certainly a good idea if you want to achieve a really good result. Also I wouldn’t recommend doing this with ordinary primer/surfacer as it is usually not thick enough to rub back.

The first step is to grab yourself a pressure-pack can or tin of black acrylic if you don’t mind using the spray gun again.

How To Paint A Car

Usually a decent sized pressure pack can will be sufficient for most cars, just be sure it is acrylic not enamel as enamel will react with the top coat acrylic if there is even the smallest trace of it on the panel.

The next step is to spray a light coat across your panels. Read the instructions and allow enough drying time before sanding.

For the next step I use 800-1000 grit wet and dry paper used wet and with a sanding block. Once again you want to follow the lines of the panel and keep plenty of water on the surface. As you can see (hopefully!) from the pictures some of the repairs that we did are far from perfect and although the door looked good these imperfections would have showed up after the top coat was on. Hence the reason to use a guide coat!

The beauty of high-fill primer is that 99 percent of the time you can sand out these imperfections without the need for more filler or reaching the bare surface below. Be extra careful at the edges of the panels as it is easy to sand through the primer there and as with the speed file, don’t be tempted just to sand one little area to get rid of all the guidecoat, keep the sanding block moving across a large area until all the guide coat is gone. If you do happen to sand through the primer it is simple a matter of applying some more primer and a guidecoat to the area and sanding again.

Once you think you have sanded the entire panel wash it down with clean water and check for any remaining guide coat, re-do any problem areas and finally either dry the panel with compressed air or leave it out in the sun for an hour or two.

An important note regarding primer – 99 percent of primer/surfacers, spray putties etc are porous meaning that they will absorb moisture. The amount of time between applying the primer and the top coat should be as little as possible and once the wet sanding is finished be sure to dry the panel down as much as possible. Any moisture trapped in the primer has the ability to ruin our nice new paint job. Not good!

Part Seven is finally done – Click Here.

15 thoughts on “How To Respray A Car – Part Six – Guide Coat

  1. No rush but i am just wondering how long until you think Part Seven will be posted? Are you going with a metallic paint and clear cloat? What is written on the handle on your spray gun? most of the guns on ebay seem to be HVLP. Been great reading as its hard to find information explaining the entire job. Thankyou for sharing. Also do you recommend a certain temperature range in which you do all the body filling and painting etc? So that it dries correctly.

  2. Hi Steve,
    I’m slack I know! I’ve been having a lot of trouble with my back, got a couple of buggered discs from bending over bonnets for ten years and am having trouble getting to the spray painting tutorial. If you can hang out a bit longer I’ll get on to it as soon as I can.
    Yes, I will be using a metallic paint on the Commodore with a couple of coats of clear over the top.
    The letters HVLP on the spray guns refer to High Volume, Low Pressure which is exactly what you need for spraying acrylic and/or 2 pack enamel’s.
    As for the temperature range, acrylic paint and body filler is fairly forgiving in this area however I would try and avoid extremes – anything under 10 degrees or over about 25 or so should be avoided in my opinion. Also if there is any moisture in the air don’t paint, pick a day that is nice and sunny to avoid getting any moisture blisters under the paint surface.
    I hope this has helped you and I’ll send you an email when I get the rest of the tutorial done if you like.

  3. Hey Josh,
    My recovery is taking a lot longer than expected and to be honest I’m not sure when I’ll be able to finish the tutorial. My apologies, believe me I am going nuts sitting around and can’t wait to get back into it(pardon the pun).

    I’ll let you know the minute I get the next instalment done.

    Thanks for your patience.
    Craig

  4. Absolutely brilliant DIY, as I am slowly,(also due to a re-accuring back problem),restoring an EJ Holden that needs to be taken back to bare metal.
    It has been a great help in pointing me in the right direction. I know how the back feels, but am eagerly waiting for part seven and beyond.

  5. Thanks for your support! I’ve made a promise to stop feeling sorry for myself and get on with things so expect Part 7 to be posted Tuesday this week, Wednesday at the latest. I’ve just got to get some photos organised from this weekend and do the write up.
    I’ll send you an email when it’s up if you like.

  6. i have just started with spray painting i was wondering if u could send me the link for all the part i am having a bit of all time finding each part:( also i just finished school
    which would be better to get in to panel beating or spray painting not just for the money but would u be able answer these question please
    1 which is harder spray painting or panel beating
    2 which makes more money Spray painting or Panel beating
    3 which earns you more money spray painting or panel beating
    4 which is more time consuming spray painting or panel beating

    i just bought myself a charade 2 door for just a project
    it is a 1995 model odmeter states that it is on 150… kms but it is not working also the speedometer is not working either how would i be able to fix that please

    also sometime when i turn the car on it makes the whole car shake say if i was in the car it would be a 7 out 10 earthquake scale it is a manual 5 gear 4 cylinder the owner i bought it from stated that he hadnt used the car for over one year i bought it for $500 the body is good apart from left guard damage can u please email these answer question and the respraying guide to random_arab_@hotmail.com thank you in advance

  7. Hi Omar,
    I may not be able to answer all of your questions but I’ll do what I can for you.
    To find all parts of the Car Respray tutorial go to http://autofix.com.au/blog/articles and a little bit down the page you will see the links to all the current articles. I have two articles to go however I am unable to complete them at the moment because of a back injury but I’ll let you know when they are posted.

    Being a Motor Mechanic by trade I am unable to answer your questions regarding the wages etc. of Spray Painting versus Panel Beating. You would have to contact some people in the industry to get answers to those questions.

    Regarding the Charade, I would say that the speedometer cable is broken or there is something wrong with the speedo head itself. Replacing the cable differs from model to model and car to car so I suggest getting yourself a workshop manual (usually available at spare parts shops) for instructions on how to check and replace the speedo cable.

    With the problems when the engine is running I suggest carrying out a full tune-up of the engine e.g. replacing spark plugs, ignition leads, fuel filter, air filter, checking the ignition timing and a compression test of the engine would also be a good idea. Doing all of this will give you an idea of what the problem may be and is a good place to start. Once again a workshop manual will come in handy for doing these jobs with instructions particular to your vehicle.

    Hope that helps.

  8. Hi Craig,
    Love the articles, there great.

    Im just a little confussed though! If the primer regardless of whether its primer/surfacers or spray putties absorbs mosture so much, then why doesn’t wet rubbing it cause issue when the top coats are applied? Hope this question isn’t stupid!

  9. That’s not a silly question at all Billy! Because the water is only in contact with the primer for a short amount of time while wet sanding the panels the primer has the time to dry out any moisture absorbed.

    It is when you leave the primer on for say a couple of months and the car is subjected to continual moisture through dew and rain etc that you will start to see rust form under the primer.

    Hope that makes sense!

  10. Hi Craig,
    I have a question regarding the quantities of material required to paint a car. I know that Marc has already asked some questions on this matter and others may have as well but I just want to get this perfectly clear.
    Let’s assume that one is going do a full bare metal paint job on a Falcon size car, in Acrylic paint and the colour is going to be metallic.

    Would the following be correct or not?

    4 litres of Primer? Requiring 6 litres of thinner?
    Plus
    4 litres of Paint? Requiring 6 litres of thinner?
    Plus
    4 litres of clear? Requiring 6 litres of thinner?

    Total thinners = 18 litres but if you allow for clean ups etc you might as well buy a 20 drum?

    I know my question may seem stupid to some but if I knew the answer I wouldn’t ask them. And maybe, just maybe someone else was just as confused as me lol.

  11. Hey Billy,
    You’re dead on the money, you will use around 20L of thinners for a large car respray by the time you factor in clean-up’s etc.

    Have a talk to your paint supplier before buying a 20L drum as some paint brands require different thinners for the different paint types e.g. primer has it’s own thinner, colour has it’s own type of thinner and the clear may require a different thinner again. This doesn’t apply to all paint brands though so have a talk to your supplier first.

  12. Thanks Craig,your the best!

    Oh but i got plenty of question for you so you’ll probably be sick of me soon hahahha.
    Takecare
    Billy

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