Harbor Freight rotary - first try

[BlkSapphire]

Posting this because my arms are tired and because I`d like feedback from people who`ve done this before. Would especially like to know if I said anything wrong or dumb.



All I really wanted to do was remove some mild dealer swirls from my new BMW, but then I got the idea I`d practice on my `95 first, and now $1000 and 4 weeks later here I am with a rotary and a 5.5" orange pad, polishing SIP into the `95`s paint. This paint has never been corrected in 13 years and though it looks good, it is covered with scratches, random in orientation and quite variable in depth - probably 10 of them are down to primer, another 10,000 of them are not. I believe the board calls these RIDS.



The HF rotary is variable. The 7" backing pad seems a little optimistic; I don`t see this thing driving much more surface area than the 5.5" pad. Working with a rotary is less bad than everyone makes it out to be.



First of all, it`s just not that dangerous. If you have any wit at all, you will run the buffer over the paint and then touch the paint where the buffer was just sitting, until you get the idea of how much heat you are producing. Very hot? You are generating too much heat. Body temperature? It`s fine. I just decided that I was not going to leave the buffer in one place for more than a couple tenths of a second - always moving - and the paint never did seem to warm up over 110 or 120 degrees.



Second of all, SIP is forgiving. It is made of abrasives sitting in a Vaseline-like lubricant. Warm it up and the lubricant starts to move smooth and easy as the abrasive reduces. This is ideal. Warm it up too much and the lubricant evaporates too quick and you are left with swirls of white clumpy abrasive. This is also bad. Polish lightly and the abrasive reduces before the lubricant goes away, leaving a clear film of lube with totally-reduced abrasive in it. It is easy once you get the hang of it. The hard part is using the right amount of SIP for the area you`re polishing, and not taking on too much area at once.



There is a place on my paint where a bird pooped so I really bore down with the SIP there, using all the weight of the rotary plus a little more. I was half afraid the paint would burn. Instead, nearly all the scratch marks in that area went away. It really improved the paint considerably. So it is sort of a learning process to get comfortable with your tool and learn what it does.



Compared to the Porter Cable, in my hands I find that the rotary takes about 10% as much effort, slings 10% as much polish, is about 10% as obnoxious on the hands (vibration), and removes about 5 times as many scratches with the same polish and pad. It also is nearly 3 times as expensive. It`s not clear to me exactly why people are so jazzed about the PC.

[trig]

Good review. I`d like to hear more and maybe see some pictures.





Were you using the HF backing plate, or a purchased one from somewhere else?

[Robb]

Can`t wait to see some pics

[BigJimZ28]

??.... how do you drop a grand

and only end up with a Harbor Freight rotary

[imported_weekendwarrior]

You sling product with the PC?

[trig]

??.... how do you drop a grand

and only end up with a Harbor Freight rotary

He probably means a $1000 car.

[BlkSapphire]

Heh, I have an HF rotary, a PC, a quart each of SIP, Nano and Ultrafina, a bunch of pads, a foam gun, like 11 different things made of microfiber, a squeegee, enough invisible glass to clean the Hancock building, 3 buckets, 2 mitts - the list goes on and on, and that`s just the stuff for exteriors. I also have a bunch of Zaino stuff, which has so far all been uniformly awesome, and a cerium kit for taking scratches out of windshields.



One thing I`m noticing is that when the polisher runs over the masking tape it is bad. The adhesive from the blue 3M tape is pretty well behaved - it doesn`t seem to migrate too much - but the tape does absorb some of the lubricant and traps a lot of abrasive, which then comes back out (dry) on the next pass. This makes everything a lot harder.



Not all the scratches are coming out. This makes me question the utility of a finer polish. Why bother using Nano if there are still SIP-resistant scratches in the paint? I am thinking an LSP with some fill ability would make more sense.



I am taking pics as I go and will post them when I`m done.



You sling product with the PC?



Yeah, I found that when it`s set on 6 it tends to sling no matter how well the stuff is `worked in` prior to that. Annoying.

[wannafbody]

the orange pad isn`t the easiest to use with the rotary. It`s a bit stiff and akward.

[qwertydude]

The 7" pad is actually an appropriate size if handled correctly, and if in a rush it can even use 10" pads, it`s plenty powerful. You`re supposed to tilt the polisher slightly so you only use 1/4 of the pad at time on the paint, not the whole pad face, this prevents bogging and heat build up on the pad, the large size means at lower rpms you still get tons of pad speed and great cutting power.



Where the skill comes in is that to efficiently polish out scratches you have to tilt the polisher in different directions each pass. Since you`re only using part of the pad face the direction of cut is either up, down, left, or right. Four quick passes in each direction is usually enough to remove defects and with the power of the polisher and large pad you should be able to do an entire car hood in about 10-15 minutes.



Oh and when cutting with compounds you need to use wool, it cuts with less heat. I personally don`t like the PFW, straight wool gets me great hologram free results.

[ABQDetailer]

After going through two HF rotaries I`m pretty sure you`ll be buying a Makita or Dewalt sooner rather than later. The 9227C is SO much better. You`ll be so happy once you get a real rotary. If that HF starts having a mind of it`s own it`ll be time to trade it in for some 476S...

[BlkSapphire]

qwertydude: that makes a lot of sense. The pad does tend to bog as the polishing goes on, using different quadrants with different polishing directions seems like it would be a good strategy. I generally make about 4 passes anyway.

[danponjican]

I still have a HF rotary sitting in my garage but the Makita is worlds better with the soft start and mainly, the constant speed control rather than just a voltage switch for a trigger.