Has Anyone Used One of These Square Floor Sanders?

[fireandrain 39]

I need to do some sanding on the floor of an Ipe tommorow and am trying to decide what to use this time. I have stripped appx. 80% of 2 coats exterior Urethane from this deck so I need to get the last of it off and get it prepped for staning on Saturday. My thinking is that a drum sander would be too aggressive and a hand orbital too time consuming taking into account the widespread nature of the remaining stain needing to come up.

Has anyone used on of these square sanding units? The guy @ HD Rental swears by them... Any input is appreciated! I'll be posting pics of this Ipe over the weekend. Thanks!

[Beth n Rod 1,279]

Yes, Rod has used them with success. :)

Beth

[Anthony G 14]

I have used them on hardwood floors on the interior of rental apartments. We love them for this purpose. Decent speed just will need something smaller for the corners but I am sure that you already knew that.

[MMI Enterprises 289]

As I just mentioned in pm to you Matt and in past posts, NO!, Do not waste your time. They suck!

The small amount of vibration/orbit is nothing compared to a low speed swing machine and it's full on rotation. If you can't score on a older Clark swing machine in the 19-20" size like from a flea market or craigs then a 17" rental (with the sandpaper driver) will suffice. Rental drivers are all 17" anyway. Any good rental lot or some HD's will have this stuff. Backing up the paper with any floor pad will lessen the bite a tad. I use 36 grit then 80 grit when I need to remove or smooth permenant type coatings or prep crete. This type urethane your dealing with is a breeze for a swing machine process.

[Beth n Rod 1,279]

The problem with the unit you have pictured above and removing a urethane is that it (the coating) will clog the paper quickly.

I suggest a drum sander first to remove the material and then come back with this unit to smooth things out. You may also need an edger unit or if you have one available; a grinder 7" variable speed to do the edge work. On ipe, be careful not to burnish the wood as the heat from the sanders can draw out the extractives and cause them to form an impermeable barrier which in short means the finish will not penetrate into the wood.

Drum sand with 36 grit to get to the bare wood, then, square sander with next higher grit available to smooth out any drum sander path/grit marks.

Yes, to do it right, you will need both machines. Each has a purpose and by utilizing them both, you will be able to get the best result quicker which maximizes efficiency and provides the potential to make a better buck at the same time.

The pics in these links were done by the method I described above:

Pressure Washing and Contractor Cleaning Forums - The Grime Scene

Pressure Washing and Contractor Cleaning Forums - The Grime Scene

I would never recommend any type of rotary machine on wood as it will leave swirls in the grain which upon application of the final finish will become obvious.

Rod!~

ps, call me if you need more info.

Edited August 29, 2008 by Beth n Rod
further elaboration

[sthom21 14]

I couldn't tell from this post if you ever used a drum sander so I would like to put in my two cents just in case. If you have never used a drum sander with 36 grit, I suggest trying it on a couple pieces of old decking or a piece of plywood before using it on a customers deck. 36 grit will take alot of wood very quickly if you are not careful. It is very easy to leave divots and end up with an uneven surface. Practice is key to getting a smooth surface with a drum sander. Even 80 grit can get away from you if you haven't done it before. The processes mentioned above are definitely the right way to go, but be very careful as it is easy to take alot more wood than you may think are taking.

A possible alternative: It will take quite a bit more time, but if you have a belt sander, it would be alot easier to contol than a big drum floor sander, and alot easier to fix any problem. Good Luck!!

[MudDuck 20]

I'm glade this thread came up,,I've got a guy that has two floor buffers he's trying to sell me. One is a High speed which I know I don't need the other is a 17" low speed which is what I think might come in handy from time to time or worth having around. He wants 300.00 for both which sounds like a decent deal. I told him I was only interested in the low speed and he's thinking of a price. (He wants to sell both at once) Kevin you seem to know about these is that what I want (it is a buffer he says but I'm thinking it's all the same?) and what do you think would be a good price for it. I don't know the brand but this guy did floors and said he got tired of it and selling out. You or anyone else can pm me if you don't want to respond here. Correct me if I'm worng about a low speed "buffer" is what your talking about your just putting sand paper on it. Thanks,

Edited August 29, 2008 by MudDuck

[MMI Enterprises 289]

To be clear, what Rod says about rotary marks is not unfounded as I am sure people attempt or step into trying a process without understanding it. The facts surrounding any sanding process says that you must 'step up' grit accordingly as a project dictates. The reason a rectangle machine is more foolproof and a drum takes a learning curve is due to both the amount of mechanical aggression from the weight and movements they produce. Rectangle orbital is weak on both the weight and movement, drum is strong on both weight and movement. Enter the low speed buffer/swing machine. Most often they are of a low to mid weight and but good on movement of the paper as it is a continuous swath or turning in one direction. The movement is slow on rpm though which s a good thing when considering accidental burnishing of wood. How you can mess up with a low speed swing is by not stepping up when required, going too fast in swinging it, not backing up the paper with a floor pad to cushion the aggression when aggression is not needed. A hard plate with thin rubber backer equiped with 36 or 60 grit will cut down anything without too much worry whereas a rectangle orbital will float over. As I mentioned to Matt in pm, a 10x10' section of catylized poly can use up abit of paper and a good hour of time with one of those rectangle machines. Figure at least a grit size lower for a rectangle machine, and from 2 to 4x's the paper use and time it takes. That said, the coating he is dealing with is not really tuff stuff for sand paper...especially when it is turning in one direction and being cut into with a low speed.

Muduck,

Buffing is polishing by way of fine abrasion. Burnishing is polishing by way of heat friction which by nature includes some level of really fine abrasion. Difference between the two is the abrasion/pads used and the speed of the equipment. Low speed is from about 175-350rpm or so..and high speed is 1200-2500 rpm with 2000 being most common. Weight is a factor that requires thought on both type machines.

In the old days I used electric high speeds that would do 1200 as they had no front wheel to lessen the weight of the machine. High speeds roll forward on two rear wheels whereas the wheels of low speed swing machines are suspended so the machine floats side to side. Add a little front wheel to a 1200rpm high speed and ya goto about 1500 with about 7lb of pressure. Up the motor size to current house amp maximum's and you get up to the 2000 rpm level but still with hardly any weight. Such machine is good for hospital use where noise and fumes are a concern. They best on soft floor finish. Pad and finish selection for these things is a whole science by itself. I currently use a 28" monster with a 17hp kawi engine. Is an amazing machine. The speed of it sucks the pad down and power assists it forward. Also has a clutch and a catalytic convertor for almost zero emissions.

I use low speed for many processes on many surfaces. Is the single most important machine in my arsinal that I can fall back to if need be.

Well anyways.. the $300 deal for two machines you mention is good. Buy them both. Swing alone for $300 is good and the 17' size is common with pads readily available. During slow times the low speed can be used for vinyl or concrete stripping, kitchen grout scrubbing, or carpet cleaning. Such prep work is worth anywhere from 6 cent to 30 cent depending on what your doing with it. The high speed is only for shining up floor finish/wax. 3-8 cents common money to made with it.....

Hope this info helps some you guys into speeding things up on the wood care or filling your time and being able to offer more services during the slow times. :)

[Beth n Rod 1,279]

Kevin,

That may be your best post yet! :dancing:

Beth

[MMI Enterprises 289]

Kevin,

That may be your best post yet! :dancing:

Beth

Well thanx..just clearing the cobwebs from being down SoCal on vacation.

[CB works 14]

I have done around 10 to 12 ipe decks and out of those 10 or 12 decks 2 might have been perfect with no warped boards. The problem with these large sanders is that if there are any cupped boards you can't get down to the bottom of the "cup".

I use either an orbital sander for the smaller decks (under 500 sq ft) or a variable speed grinder, with a pad I use for sanding surf boards that is very flexible for the larger decks.

If you use drum sanders, and you have cupped boards, do you have to sand the edges of the boards to get down to the middle of them?

[fireandrain 39]

If you use drum sanders, and you have cupped boards, do you have to sand the edges of the boards to get down to the middle of them?

I don't normally work with a drum sander but did today for a few hours. Same issue with Ipe cupping.... How DO you get at the bottom of the cupping on a deck board???

[RPetry 564]

... If you use drum sanders, and you have cupped boards, do you have to sand the edges of the boards to get down to the middle of them?

That would be just short of impossible with ipe'. The wood is hard as nails.

[Beth n Rod 1,279]

Bottom of the cup; wouldn't even try on Ipe' with a drum sander. get out a grinder and conform to the cup with it and then orbital sand to remove the cross grain marks.

Rod