Grinding - Sanding - POR - Painting

[CoastGuardZ]

I am getting ready to repair a few (rust?) bubbles in the paint. The affected areas are the doglegs and a small spot on the cowl, pictures are attached. I have next to nothing that I need for this and therefore need to get a shopping list together and y'alls help would be greatly appreciated.

I do have an air compressor. A small stand up Craftsman model. 3hp @ 90psi / 1.5hp @ 150psi w/15 gal tank.

I was thinking of buying an angle grinder but feel this may be overkill for the job. Should I just get a DA? If I do get a grinder will a 4.5" 10 amp 11000 rpm DeWalt grow with me through the rest of the restore in the years to come or do I need to shop for a 7" ? or both? What attachments would I need for this job?

If a DA suits this job better, what should I look for? What attachments would I need? Best brands to buy?

POR15 seems to be the most popular way to go and I've seen reference to Zero Rust (?) lately. This may not be a permanent fix as I plan to have the paint and body professionally done in 5 years or so. Will POR cause any issues for a shop later on? Should I buy the "starter" kit or piece my own together? Best place to buy? What other cleaners/strippers/etchers/primers will I need?

I intended to rattle can these "repairs". Last year I bought a touch up tube of Atomic Orange (A16), a color available on '03 Xterras, to fill in a few chips and the match is uncanny to the Maaco like paint job that is on the car now. Nissan does not sell rattle cans of thier paints, does anyone know if there are paint shops that can make rattle cans? I haven't checked Dupli-color yet, they may have it available.

Please fill in any areas I've left out. Thanks in advance, I look forward to your responses!

Nate

[hls30.com]

Nate,

Those Doglegs(at least one of them) are probably just holding on, and need to be replaced. Unless that is your intention, I would attack them (and the cowl) from the inside with metal ready and some POR to stablize them for the next 5 years and get the job done once, right. POR is a roysl psin in the A$$ to remove, and is made for permanent not temporary repairs.

Will

[CoastGuardZ]

snip POR is a roysl psin in the A$$ to remove, and is made for permanent not temporary repairs.

Will

Good info, Will. I suspected as much. I may try the other product since it is supposed to be a spray on. I'm not looking to replace any sheetmetal just yet, but like you said "stabalize" it for now. I pulled the cowl last year for a look-see and the underside was in good shape, so I intend to POR or similar this time.

As far as tools and chemicals go, any suggestions Will?

Thanks-

Nate

[BD240Z]

Nate,

If you're unable to get a good enough color match from spray cans on the shelf, a paint supply house can mix up your color, (by the paint code) and put it into spray cans for you. The supplier I use has a two spray can minimum and the price is around $10 per can. You might have a small difference in color from what's on the car now but it should be darn close

I agree with Will, keep the por products on the inside and any filler, primer and paint on the outside. Good luck with your efforts.

Bruce

[Bruce Palmer]

.... is Kevin Tetz Metal Prep and Rust Repair DVD. It is put put together by a professional for the DIYer. go to www.paintucation.com

Just keep in mind that what you are looking at is the typical "Iceberg" scenario..... and when you start poking around with a screwdriver... OMG!

[hls30.com]

Nate,

Please don't think I have been ignoring you!

As a part of a tailight hardware project I am in the middle if, I am evaluating a different rust disolver-it may be just the thing for keeping round the house for mechanical work-and perfect for your needs in this!

I'll post tomorrow morning when my test isthrough-I think you will be enthusiasticly suprised!

Will

[CoastGuardZ]

Cool Will, I'll keep an eye out for your post...

Thanks Bruce, I'll check that out right now.

[Ed]

Nate,

Depending on the type of work you intend to do will determine the type of grinder you will need. If you intend to cut and grind away rust in those small areas your mentioning then a 3" high speed grinder is all you will need.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93157

You can buy all kind of attachements for the 1/4" arbor. Cutters, grinders, and polishers. High speed and small to acomplish the small job.

If your intention is to do some serious body work, like a fender or an entire door then a D/A will be something more your speed. The more area you want to work on the larger the contact area.

Ed

p.s. How's the little one?

[EScanlon]

I think that the differences between a Die Grinder (Angle or Straight) and a Dual Action (D/A) Sander are getting a bit confused here.

The tool that Ed links to:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93157

and this other one:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=92007

Are BOTH a type of grinder, and are generally called Die Grinders.

Because of their size and speed they are commonly used as clean up tools as well as final shaping grinders. These are extremely handy in that you can use wire wheels, Rol-Loc grinding disks and scotch disks as well as the bristle cups.

For heavier grinding on sheet metal, the disk and face on this style is changed to a rubber backing plate and 9" or larger grinding disks:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93179

Although a hard disk gets used to coarse grind very heavy pieces of metal.

For grinding on thick metal with more control:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=31309

That last one also gets used to clean up welds and cutting through thicker structural sheet metal. But if cutting sheet metal will be done often, there's this item:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90114

Sometimes you need a middle of the road between a solid disk grinder and a flexible disk grinder. Additionally, sometimes you need a flex disk sander to sand material quickly. That's where this next one gets used a lot, even though it gets referred to as a sander, it is used as BOTH a grinder and a sander. Typically you use a fiberboard backing plate with a 4-6" flexible grinding / sanding disk.

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=97187

That one has the added feature that it becomes a drill as well.

Except for the last one, every one of the tools listed above are considered GRINDERS, that is they rip material quickly as opposed to sanding it off slowly and smoothly.

Then this is where the SANDERS come in.

Sanders are either rotary (circular), straight line or Dual Action (D/A).

The first two terms are self explanatory. D/A's are a sander that both rotates AND oscillates around AS it rotates. Dual Action sanding marks look like a series of stretched and flattened coil springs, that is loop after loop all in one big looping pattern.

The biggest and probably the most important feature of the D/A is that it allows rapid and intense material removal (paint, primer, bondo) but in a very spread out manner and if properly used over a larger area. This allows sanding a large panel flat or sanding a prior paint job to as thin as possible and necessary.

There are two predominant styles. The one that everyone remembers looks like this:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90288

But this style, "palm" style is becoming more popular:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=93742

BOTH are D/A's, both have their "advantages" and adherents. The first one allows the use of two hands to apply pressure easier than the palm style. The Palm style allows the subtle and quick movements that a curved panel requires if you're going to D/A a curve.

NEITHER one is a "grinder", and generally when in use, you'll be looking to protect the flatness of the pad and the edges to ensure that the edges press down evenly (no chunks out of the edge).

This last tool is an In-Line Air Sander:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=91773

This tool gets used to quickly shape bondo to the level of the panel. Generally this will sand (depending on grit) a large area much larger than a D/A can, AND it will provide for a faster smooth transition to the bondo applied onto the metal.

For the job you're showing, you may end up using just about all of the tools I've mentioned. It all depends on just how MUCH damage there actually is behind that rocker panel, and how thorough a job you intend on doing.

Obviously unless you're really into doing bodywork, you're going to have to pick one or two.

With that limit being imposed, I would choose these two:

5" HIGH SPEED AIR SANDER WITH JACOBS® CHUCK

(Item 97187)

and

6'' DUAL ACTION AIR SANDER

(Item 90288)

But the FIRST thing to determine, is how much rust you have. That may influence everything.

FWIW

E

[beandip]

Nate,

Those Doglegs(at least one of them) are probably just holding on, and need to be replaced. Unless that is your intention, I would attack them (and the cowl) from the inside with metal ready and some POR to stabilize them for the next 5 years and get the job done once, right. POR is a roysl psin in the A$$ to remove, and is made for permanent not temporary repairs.

Will

Nate, we seem to have gone on to the equipment part of the problem. Back to the repair. Will has hit the ''nail'' on the head. Remove the trim from inside and have a look in the cavity of the dog leg. You most likely will find the rust has gone through the sheet metal causing the bubbles in the finish. You can Temporally repair this with POR . If it isn't so bad that the car is weakened in this area. From what is shown it shouldn't be. Be SURE , if you use POR that you follow the instructions from the manufacturer . Use the marine clean and metal ready to prep the metal , and it is imperative that the area to be treated is dry. You my need to use some of the ''cloth'' to cover the holes from the inside. I have found if this is needed , to paint on the POR and let it set until tacky then apply the cloth and press it in place. Then while still tacky paint on another coat of POR. I actually sprayed the POR into my rocker and doglegs . I didn't have any rust through only surface rust. I dodged that bullet . Harbor Fright has a syphon ''gun'' that works well for that . Only $6.00 too. I doubt the compressor you have will handle any of the air tools that have been recommended. They all need much more volume . I have a electric palm sander meant for wood working . It is a D/A Porter Cable brand . I used the hell out of it on my Z. When I was preping my Z for paint. Since I have no apparitions to be a professional body/paint guy I just used what I had . I did buy a set of air tools at Costco and also a angle die grinder from Harbor Fright which I used as much as any tool in my project to make ready for paint dealing with the rust issues, and doing the mechanical work. Even these little die grinders use lots of air volume you will find. Not so much pressure but volume . Gary

[CoastGuardZ]

Awesome info guys! I appreciate all the input and advice from all!

E- I'm a knowledge junkie, so I always look forward to your posts. Thanks for yet another well delivered "article".

I'm planning a trip to Harbor Freight tomorrow, they have a 40" 13 drawer roll around tool box to replace my overstuffed dinky mickey mouse bottom box I have now. Anyone have any input on this box?

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90320

I'm planning on picking up the air grinder that Ed mentioned (thanks bro)...

http://www.harborfreight.com/cpi/cta...emnumber=93157

and most likely the two that E mentioned as well...

5" HIGH SPEED AIR SANDER WITH JACOBS® CHUCK

(Item 97187)

and

6'' DUAL ACTION AIR SANDER

(Item 90288)

As far as how much rust I have there, we're all just guessing until I have the right tools to determine the damage, otherwise I'll be scrapping at it with a pocket knife and screwdrivers

I'll probably pick up the syphon gun that Gary mentioned, too. Although I'll have to hold off on an Air Compressor upgrade for now or the Wife will take back the check book

Any recomendations on what type attachments/accessories to get and how many of each type would be a good starting point?

Nate

[EScanlon]

In the FWIW dept:

If you're planning on spending $400 on a new tool box but putting off upgrading the compressor.....I would personally change that.

A properly sized compressor will allow you to run the tools you ARE planning on buying, without waiting...and waiting....and having lots of water in the line....and waiting...and more water....Get the drift?

The "small stand up Craftsman model. 3hp @ 90psi / 1.5hp @ 150psi w/15 gal tank" you mention is perfect....for a nail gun, screw gun, and other short bursts of air, but simply inadequate for the task of running a D/A, Grinder, Paint Gun, etc. etc. (By the way, I'm guessing you mean 3 SCFM @ 90 PSI AND 1.5 SCFM @ 150 PSI, which is how they're rated.)

For the $400 instead of the tool box you could pick up a good sized compressor that would have no trouble doing the tasks you've mentioned and more. But, we can cover the sizing on compressors on another post.

FWIW

E