Bog done... what next?

John (and other pros) - I have used filler to get what I feel is the new profile of the door skin but I want to know where I go next to ensure the surface is perfectly smooth and flowing. There is nothing worse than looking along the side of restored/modified cars and seeing a 'cellulite' surface.

Go over the filler work with 400 to get rid of deep scratches, blow out dust and wipe with prepwash..dont use water. Then spray on some high build primer (hi-fill) once dry mist on a guide coat with some black paint. Then wetsand with 800. Repeat filler or hi-fill if necessary then prime and paint.

Thats what I do in a nutshell.

Oh and remember to use a block when you sand to get a flat uniform surface.

Hi Peter,

With respect to Candy, I would suggest a few more steps prior to priming etc.

If you have finished the major sanding and want to save a SH*T load of time effort and material later, and get the flatest surface you can minus the deep grazing scratches of the main sanding, then the best way is to do the following.

#1 Get yourself a VERY flat piece of ply wood, pref Marine ply, it should be the size of a sheet of sand paper folded in half and 15mm smaller around the outskirts than what the paper is, in other words if you get it right the folded sheet of paper should fold around the edges of it, the idea is that you have a paper platform that allows you to hold it and the paper with an open hand at the finger tips.

#2 Go to the kids old school desk and find a blacklead pencil (soft 2b-6B) then scribble all over the body filler area you want to surface, cross hatch it vertically and horizontally with lines 5-10 mm apart, this is how I taught my apprentice to surface body filler and I still do the same today.

#3 Now position yourself so you can execute long strokes (SIMON don't bother with any filthy remarks) on flat panels always work horizontally each time you sand over an area move down a fraction on the next run so you have an overlap, on curved panels also sand in the same horizontal plane but at 30 degree sweeps and follow the contour of the panel, I usually use 320 white oxide paper for this task, anything more is overkill.

What you will see is the lines you scribbled start to disappear, you will most probably also see small patches or low spots with the gridded lines still visible, never ever works on them in one spot attempting to delete them, continue the elongated sweeps over them and the areas that have already lost the pencil marks, its these area's around the low spots that are still to high in reality.

To see if you have accomplished what I have prescribed, take an old T-shirt (Cotton) and use a layer of the material across the palm of your hand, gently wipe over the area you have sanded, close your eyes (I'm serious) and concentrate on feeling the surface, you will either feel a flat surface or imperfections, the reason for the material is that your bare hand actually sticks to the surface as you cross it and this diminishes your sense of touch, the cotton wool actually stops this yet allows you to sense what the surface is doing.

#4 If you come across high spots of metal coming up as you execute the above, stop immediately and take a pick ended finishing hammer (point ended hammer) and dolly and just gently ease the high spot down with multiple gentle taps, then continue sanding, there is no need to refill these lowered high spots when you are done as the highfill should do the job.

Last, after its all done, take some prepsol and wet the surface horizontally then gun sight the panel, if all is well you should see a very flat although dull reflection in the panel.

NEVER EVER rub down the filler with wet and dry paper and water, filler is porous and the water will make its way to the metal below which could cause drama's later.

If you take these steps, you will use less hi-fill (I prefer EP these days) spend less time doing the final surfacing and end up with a much better pre-prime surface and eventual finish.

Cheers

John

+1 ^^

#2 Go to the kids old school desk and find a blacklead pencil (soft 2b-6B)

Maybe when you went to school.

These days they have laptops and ipods and use ROFL and LMFAO instead of words??

... you will use less hi-fill (I prefer EP these days) ...

Is 'hi-fill' what I remember as spray putty? I don't have a compressor so is a pressure pack can okay?

I think I'm following you and I've been using the pencil crosshatch technique with this sanding tool. Is this suitable to use in lieu of the ply sanding block you describe? Thanks.

Yes Spray Putty is the same thing. Pressure packs are fine, as high fill doesn't require high pressure anyway..but pressure packs can be expensive. You can also get roll or brush on high build primer if you want aswell.

Is 'hi-fill' what I remember as spray putty? I don't have a compressor so is a pressure pack can okay?

 

I think I'm following you and I've been using the pencil crosshatch technique with this sanding tool. Is this suitable to use in lieu of the ply sanding block you describe? Thanks.

Yes peter you are doing fine with that speed file although I prefer something with more width when blocking back.

As far as not having a compressor, I see you read my prep tutorial, just get an airless spray unit, less chance of humidity problems especially this time of year and far less material loss or overspray if you are working from home.

Yes Spray Putty is the same thing. Pressure packs are fine, as high fill doesn't require high pressure anyway..but pressure packs can be expensive. You can also get roll or brush on high build primer if you want aswell.

Guys Guys Guys, spray putty and Hi-fill are not the same thing, spray putty's are mostly acrylic based combining the product and thinners, Hi-fill's are 2-pac (Read 2 part based although its actually 3 as there is the product, reducer and hardener)

History lesson, why was acrylic invented?

Cars have generally always been painted in enamel's, however by the 1960's panel shops wanted something quicker and more workable and therefore acrylics came onto the market, done correctly a car can be totally refinished in acrylic based products and has been the choice of Hot Rodders for decades due to its ease of use and the fact you can cut it back to a 100% mirror finish, however for everyday use of a motor vehicle and longevity 2 Pac's are always the way to go.

A good example of a manufacturer using acrylics with dire consequences after a few years can be seen in Holdens HQ thru HZ series, these cars used an acrylic version which after a few years paled off and lost all of its shine, I'm sure we all remember seeing examples of it, in the lead up to the Commodores Holden started using enamels again on the last of the Statesmans.

genrally, acrylic can be sprayed over enamel as long as the first few coats are kept as dry as possible otherwise the thinners will bite into the enamel base and start frying up like paint stripper, these are 2 different compounds, however spraying enamel over acrylic although totally possible is not recommended, the acrylic material is genrally softer, its like pouring concrete over sand instead of gravel the base just wont support it long term and under heat and cold conditions the 2 have differing expansion and contraction rates, eventually you end up with crows feet and the like as the 2 start to delaminate.

I WOULD NEVER USE  A SUPPER CHEAP AUTO OR ANY OTHER SOURCED SPRAY PACK BASED ACRYLIC SPRAY PUTTY UNDER A FINAL FINISH,  these were only ever designed for small hand sized applications not full panel applications.

Yes you can use a small sponge roller to apply Hi-Fill also, but this also was only ever designed for small spot repairs not full panels and if you are not careful you can end up with air bubbles in the application.

I have followed John and Candy's advice and I feel I'm ready for the spray putty. I asked around where I could get a Little Beaver and most told me a certain building in the industrial area... despite that I did manage to get an el-cheapo electric spray gun from Bunnings.

My question now is, how do I prepare the spray putty? Does it have to be mixed before it goes into the spay gun and what steps do I need to take before and after? Again, many thanks.

I asked around where I could get a Little Beaver

In canberra, we have a place called 'Sinsations'

Im sure there would be something similar in Kings cross....

My question now is, how do I prepare the spray putty? Does it have to be mixed before it goes into the spay gun and what steps do I need to take before and after? Again, many thanks.

The oracle (Sirpent) will be able to tell you for sure, but one thing i have learned is the EVERYTHING should be mixed before pouring into the gun.

It makes a huge difference to what comes out the spray end.

In Canberra, we have a place called 'Sinsations'

Im sure there would be something similar in Kings cross....

GOLD !

In canberra, we have a place called 'Sinsations'

Im sure there would be something similar in Kings cross....

 

The oracle (Sirpent) will be able to tell you for sure, but one thing i have learned is the EVERYTHING should be mixed before pouring into the gun.

It makes a huge difference to what comes out the spray end.

I have followed John and Candy's advice and I feel I'm ready for the spray putty. I asked around where I could get a Little Beaver and most told me a certain building in the industrial area... despite that I did manage to get an el-cheapo electric spray gun from Bunnings.

 

My question now is, how do I prepare the spray putty? Does it have to be mixed before it goes into the spay gun and what steps do I need to take before and after? Again, many thanks.

Peter,

best way to do it is to get a glass jar, I save NesCafe coffee jars, follow the instructions for what ever you are using as far as mixing ratio's, put a strip of masking tape from top to bottom and then using water first work out how much the jar holds probably 3 cm's from the top, then work out your  material quantities as per this capacity and mark off first, the spray putty, then hardener if it uses one and finally thinners / reducer.

Dry the jar and you have a good stable vessel for mixing moving forward.

When using an electric spray gun, you don't need as much reducer / thinners, so start of by using a 1/3 of what is suggested for an air atomised system, if its too wet still reduce the amount again, otherwise if it seems to dry and doesn't spray properly increase it slightly.

Make sure you really do a good job stirring it before you put it in the gun pot to spray and always make sure you leave no primer in the gun and strip it down and clean it well before you pack it away.

Cheers

John

It all depends on your brand or type of spay putty/primer and the environment your painting in etc. Basically mix putty/primer and hardener (if 2 PAC) for a high build, or you can thin it out with thinners for areas that dont require a high build to fill inperfections or for later film coats for consistancy. Ask your paint store or refer to label for accurate ratios for application.

I would go to more detail, but I'm replying from my phone and I'm sure John will jump in with his input.

Ahh I see John already got his answer in 1st. You can also buy disposable mixing cups from paint shops or hardware stores if you like aswell for like 20c.

are you aware of the health and safety rules that accompany 2-pac?! doesnt seem to have been mentioned.

Was in my prep tutorial which Peter has read, but very good point.

To add few more things.

Peter.

Smallish air comp can be bought for $150. spray guns another $50. try go for 1.3-1.5mm nozzle.

for $200 outlay your job will be easier and better. Air comp are always handy and the small ones are easy to store away.

I got a small 2.5hp air 25L comp paid $99 for from Bunnings. use it for small jobs. though i do have a large industrial air comp with quite expensive spray guns for my bigger jobs.

Even with small compressor you cannot do a complete car at once but individual panels are possible. Ones with 40l tanks are ideal even for bigger jobs. noisy buggers but work reasonably well.

if painting 2pk stuff (i'm kinda sick of OHS relation with 2pk, im pretty sure everyone knows how bad it is so as all the other paints) so a suitable mask is required for any spray job be it acrylic, enamel or 2pk.

You cannot get it from bunnings or repco and like.

Have to go to specialised crash shops. cost of mask from $200 to 2k for full face oxygen masks for 2pk applications.

Alternatively go to a crash shop ask what they have and use and info where they get it from.

There are some paints you can get that are still 2pk with reduced harmfull crap. cost bit more but its an alternative. though i haven't seen primer filler version of this.

spray cans are good for small jobs like toys, bikes, signs etc..... cost per liter the spray cans are a lot more exy than buying a cheap air compressor and spray gun.

have fun.........

i believe the less harmful 2k are called the ISO free versions. ive seen in autoone a motorspray brand hi-build iso free 2k primer. here is a link. http://www.diytools.com.au/MOTOSPRAY-2Pack-ISO--Free-Primer-Isolator-41-4ltr.html

i did a bit of searching and for a cheap gun found a lot of people recommending the workquip p102g (<100 on ebay if memory serves). it is a gravity fed gun and comes with 1.4, 1.8 and 2.5 tips, so good for just about everything a DIY person would need. i have just resprayed my hilux over the xmas break with acrylic. had no dramas with the gun (except for when i tried to mix the primer in the gun pot, didnt mix very well ) i ran ~40psi out the gun (got a gauge and water sep) and my 2.5hp compressor kept up with coating the whole cab no worries.

for the mask, i got a sundstrom off ebay too. came with a particle and gas filter. http://www.ebay.com.au/itm/SUNDSTROM-FACE-SPRAY-MASK-KIT-RESPIRATOR-SPRAY-PAINTER-/170460214961?pt=AU_Car_Parts_Accessories&hash=item27b03876b1 one add (not that one) says that exact face mask is good for 2k (as it comes with the A1 gas filter), but then i also see they sell an A2 organic gas filter. so who knows? probably best get the lot and just stack them all haha http://www.ebay.com.au/itm/SUNDSTROM-MASK-A2-Gas-Filter-x-1-PAINT-RESPIRATOR-/170421278819?pt=AU_Car_Parts_Accessories&hash=item27ade65863