Rotary Usage

[TOGWT]

Quote: And Another Thing!


~One man’s opinion / observations~

Removing (3 Mil - 0.003”) of the paint film surface will cause premature paint system failure and the only way to rectify this would be replacement (re-painting) As a reference point copy paper thickness is 3.5 Mils (0.0035”)

How could you measure 0.003” without a paint gauge?
I would think paint shops would have access to one though

~Hope this helps~


Experience unshared; is knowledge wasted…/

justadumbarchitect * so i question everything*

[FinishingTouch]

Thanks for the help. That is a good reference point about the copy paper. I have looked at some nice paint gauges but they are pretty expensive. I don't like the magnet ones.

[joed1228]

They are very pricey and you need one that can measure multiple layers, not just the total thickness since you will be measuring the panel, primer, paint and clear.

I saw a nice digital gauge, it would measure the thickness of up to 4 layers but I THINK it was around 800-1000 bucks. Too much for me.

[Anthony Orosco]

Originally posted by FinishingTouch
I've been practicing buffing and have also had a professional painter friend of mine teach me some techniques. I am having a hard time with cars that have a lot of hard angles, such as a Jeep Cherokee. This car is nothing but edges! How can you safely buff this type of car without burning some of these edges. It's easy not to burn an edge if you have plenty of room for the trailing edge but what if you have 2 edges only about an inch apart? Help!

I was just lurking around and noticed this post and don't believe it was replied to so I'll take a stab at it.

You should first tape off edges and then always buff out to the edge. In other words start from the top of the fender, say on a JEEP front fender, and work your way out to the edge.

You can also buff up to the edge and stop a few inches away from the actual edge and finish it off by hand. If you are going to actually buff on the edge itself then you should feather the trigger as you go along the edge.

Anthony

[whatnobeer]

Great thread. I've learned quite a bit about
do's and don'ts when using a rotary. My next
question would be what is a good one to purchase
and where would you get one? Price isn't a big
deal. Looking more for quality and dependability.
Thanks.

The Beer Man

[TOGWT]

~One man’s opinion / observations ~

You mean 0.3 Mil, not 3 Mils, correct? That’s correct, thanks BlackRegal

This is what I use, but there are others just as good (perhaps better, dependant upon individual)

The Makita™ 9227 offers an electronic speed control (0-3000 rpm) that maintains a constant speed under varying load conditions. This means you can add a little pressure while working out a paint blemish without having the polisher stall or slow down. The (10 amp) motor works effortlessly for high speed polishing and the entire unit weighs only 6.6 lbs. A large wrap around handle provides excellent two-hand control for working over edges or into tight corners. A spindle lock built into the polisher makes changing pads safe and easy.

Specification:
Electronic adjustable speed control, 0-3,000RM
Power: 120 Volts AC, 50-60Hz/120V VAC
Motor: 10Amp
Speed (constant): 0 – 6,000 RPM
Spindle Thread: 5/8” – 11UNC
Weight: 6.5Lbs


~Hope this helps~

Experience unshared; is knowledge wasted…/

justadumbarchitect *so I question everything*

[Nagchampa]

Originally posted by whatnobeer
Great thread. I've learned quite a bit about
do's and don'ts when using a rotary. My next
question would be what is a good one to purchase
and where would you get one? Price isn't a big
deal. Looking more for quality and dependability.
Thanks.

The Beer Man

You really can't go wrong with the popular brands. (Makita, DeWalt, Milwaukee, Porter Cable, etc) They all have their strong points and features but overall they all do basically the same thing. Check some of the forum sponsors as well as eBay for good deals.

[ZJ JIM 96]

Great thread! I feel a lot less scared to use my rotary. I've been pretty lucky to have never really messed anything up with it, but can someone tell me what this user did wrong that caused these marks? Is this typical inexperience, a rush job, wrong pad/product, or just plain carelessness that can easily be avoided?

[Anthony Orosco]

Swirl marks caused by using too aggressive of a product/pad combination and moving the rotary quickly across the paint. Too many detailers PUSH the buffer and this causes marring because they are moving the buffer faster than it can spin and break down abrasives, hence, swirls.

This can be avoided by first using the least abrasive product/pad combo first and using a slower or lower RPM. The paint doesn't look that bad in the first place so all that should of been done is a rotary with either a polishing or finishing pad and a mild paint cleaner like IP or FP.

Vehicle sides can always be difficult to control the rotary so what I do is break the door up length wise into a top section and a bottom section and then break up the top door section into halfs, the same with the bottom section.

If possible turn up or turn in the side view mirrors, tape off the door handles and trim, including windows, and then work the first half with the rotary with the RPM's set about 1400 to 1200 for polishing and 1100 to 1000 for finishing work. Work in a hatch pattern as much as possible, meaning your first pass is say right to left, then left to right and finish with a diagonal pass. Most products can be worked until all evaporated but I like to do a second pass many times with a "wet" buff. This is when you buff but instead of working the product until all gone you buff a small area with a short pass or two then remove right away.

You know you are moving the buffer too fast if the paint is cool to the touch when done doing an area. If the paint is real hot to the touch then you are moving to slow and/or have the RPM's to high. The paint should be toasty warm to the touch for polishing and finishing.

OK, I am done..........

Anthony

[ZJ JIM 96]

Excellent explanation! Thanks for the quick response.

[theveed]

Also, practice buffing with your non-dominant arm. It saves you so much time on vertical panels when the torque of the buffer is countering your arms movement.

[ncal]

I'm going to take the plunge and pick myself up a DW 849 (and a practice hood! : D ) very soon. I've waded through this thread regarding pads to use but I was hoping someone could give me a few recommendations. Thanks