RAS 115.04, steel boat hull, and the Spark Trap

[Curtis Hight]

In the "Gallery" of pictures for the RAS 115.04 rotary sander, there is a picture of sanding paint off of metal, which leads me to these questions:

1. I assume that the Spark Trap (Product No. 484733) is used when sanding on metal. Is this correct, or is it intended more for cutting metal, and hence might not be necessary for sanding paint and resin off of steel; under what conditions am I most apt to create sparking sufficient to cause a problem?

2. The text for the Spark Trap states "For use with the Festool CT 33 and CT 33 Dust Extractors." I assume it will work with the CT26/36/48 units and the text is merely in need of being updated. Is this correct?

3. Can anyone compare Titan 2 with Saphir for removing paint and "half-inch thick" resin from a steel boat hull?

 

[peter halle]

I can only answer two of you questions.

If you are sanding or cutting metal - use the spark trap. 

The spark trap should fit any of the dust collectors from Festool, although I am not sure about outside clearances on any of the models where the intake is vertical.

Sorry that I can't help more.

Peter

 

[MrToolJunkie]

I just checked the catalog and the Spark Trap (Festool No 484733) is compatible with the CT26, 36 and 48 and of course the 22 and 33.  I am not sure that it would work with the Mini or Midi.

I think that Saphir is the toughest paper out there and sounds like it would be good for the initial sanding/gunk removal.  I have used it on metal with the RASand it worked great.

Scot

 

[AlexThePalex]

1. I assume that the Spark Trap (Product No. 484733) is used when sanding on metal. Is this correct, or is it intended more for cutting metal, and hence might not be necessary for sanding paint and resin off of steel;

You do not need the sparktrap when sanding metal. Believe me, I've sanded quite some metal in my life, and sparks, well, they are simply not part of the experience.

under what conditions am I most apt to create sparking sufficient to cause a problem?

You get sparks when you get metal on metal action, like when you cut it with a grinder/jigsaw or use a wire brush. Sandpaper does not contain any metal parts. The grit particles in Festool's sandpaper are made from either aluminium oxide or silicon carbide, both non-metals. Perhaps on some extremely rare occasions can you get a spark. Not something I'd worry about. In my experience it's easier to create a smoldering wood particle with sawing than creating a spark while sanding.

2. The text for the Spark Trap states "For use with the Festool CT 33 and CT 33 Dust Extractors." I assume it will work with the CT26/36/48 units and the text is merely in need of being updated. Is this correct?

The text apparently needs updating. When you type in the spark trap's product number in Festool USA's search box you get the following page, which states the new vacs also as compatible. Which is logical since the hose size and it's connectors didn't change.

One curious thing though: on the European websites the description of the spark trap is now changed. It specifically states it is not to be used in actions that generate a lot of sparks like with grinders and only acts as additional safety device for sanding wood which might contain an unexpected nail. Which renders the entire spark trap more or less useless, because the chance of a nail generating sparks when sanding is about zero.  

3. Can anyone compare Titan 2 with Saphir for removing paint and "half-inch thick" resin from a steel boat hull?

When you're talking about paint that's actually, SERIOUSLY, half an inch thick, I'd look at other ways to remove it than sanding. Its gonna be an impossible job, sanding that away. I'd try to start by scraping/chiseling it away with a good big scraper (4'' blade, 2' handle) first, and if you can get your hands on it, a sandblaster. That's how the professional companies do it. A chemical stripper is also a solution that might prove faster and cheaper than sanding. Only use sanding to clean up the last bits. Sanding is simply not suited for layers half an inch thick. As a comparison, we used to spray cars in the body shop with a layer of 120 micrometer. That's about 1/200th of an inch. Quite a difference. Paint on wood is generally a bit thicker, more in the 250-400 micrometer range.

Titan paper is used for high end finishes on cars and is best suited for the 120 micrometer range I was talking about above. Nevertheless, 40 grit Titan can be very aggressive. But such a low grit is no use for layers half an inch thick. Same story for Saphir. If the paint was fully cured (hardened through and through), it might take you AGES to get rid of it. But chances are, and I'm pretty sure they are, that such a thick layer will never cure completely. So your paper is gonna gum up in no time making the task even more impossible.

I'd try to get my hands on a sandblaster, start with that and go on with a paint stripper, and finally sanding for the last phase.  

 

[Michael Kellough]

Sparks propelled from steel by an aluminum oxide belt.

I can't explain what a spark is (at least not why it ignites) but you get them when a tiny bit of steel or iron is rapidly ejected from it's home. This can be caused by a strike from a hammer or stone or anything harder than the steel like aluminum oxide on abrasive paper.

Too bad the spark trap isn't really for sparks.

If you're making a lot of serious sparks you could use two vac hoses separated by a bucket of water such that the first hose ends in the water and the second hose starts above the water. Might also need to remove the vac bag, or use a small cyclone separator.

 

[festooldude]

1. I assume that the Spark Trap (Product No. 484733) is used when sanding on metal. Is this correct, or is it intended more for cutting metal, and hence might not be necessary for sanding paint and resin off of steel;

You do not need the sparktrap when sanding metal. Believe me, I've sanded quite some metal in my life, and sparks, well, they are simply not part of the experience.

under what conditions am I most apt to create sparking sufficient to cause a problem?

You get sparks when you get metal on metal action, like when you cut it with a grinder/jigsaw or use a wire brush. Sandpaper does not contain any metal parts. The grit particles in Festool's sandpaper are made from either aluminium oxide or silicon carbide, both non-metals. Perhaps on some extremely rare occasions can you get a spark. Not something I'd worry about. In my experience it's easier to create a smoldering wood particle with sawing than creating a spark while sanding.

I gotta disagree! when i use my beltsander to sand down metal pieces or spatulars/putty knives, sparks fly everywhere!.. the sparks are extremely hot pieces of
material that you sand away, and the beltsander makes them fly.. so, that are sparks.. not to be advised in combination with a wood dust/chips filled CTL..

thnx Rick

 

[AlexThePalex]

Alright, then I stand corrected in the case of belt sanders. Never used them for anything else but wood.

Must be something in the linear action then. Never seen sparks with the rotary and eccentric sanders I've used. We even had a 220mm 2200 watt rotary sander in the shop, which I used on lots of large metal structures, a real power house, never had sparks. 

 

[Dan C]

Alright, then I stand corrected in the case of belt sanders. Never used them for anything else but wood.

Must be something in the linear action then. Never seen sparks with the rotary and eccentric sanders I've used. We even had a 220mm 2200 watt rotary sander in the shop, which I used on lots of large metal structures, a real power house, never had sparks.   

Not quite- nothing to do with linear action- an angle grinder with an AO disk does the same thing.  Most of my recent projects are steel/wood combinations.  Sparks are a fact of life when sanding (which is essentially grinding) metal.  I do my grinding outside, on the driveway to keep the mess out of the shop.  Metal grinding dust/slag is the worst....

 

[RONWEN]

Not to side track the discussion but you can roughly classify metals that you are grinding by the color & formation of the sparks.
http://www.scrapmetaljunkie.com/241/the-spark-test-and-spark-testing-metals-2

 

[AlexThePalex]

Sparks are a fact of life when sanding (which is essentially grinding) metal.  I do my grinding outside, on the driveway to keep the mess out of the shop.  Metal grinding dust/slag is the worst....

Well, they are not a fact of my life when sanding metal. And I've sanded a lot of it. Cars, trucks, boats, buildings, industrial objects like air ducts and machine housings, scissor lifts, we did it all.

Sparks are metal particles that are red hot because they are removed with great friction force, something that happens with cutting, grinding or sawing. But not with normal sanding operations.   

 

[Michael Kellough]

Sparks are a fact of life when sanding (which is essentially grinding) metal.  I do my grinding outside, on the driveway to keep the mess out of the shop.  Metal grinding dust/slag is the worst....

Well, they are not a fact of my life when sanding metal. And I've sanded a lot of it. Cars, trucks, boats, buildings, industrial objects like air ducts and machine housings, scissor lifts, we did it all.

Sparks are metal particles that are red hot because they are removed with great friction force, something that happens with cutting, grinding or sawing. But not with normal sanding operations.   

It's more like speed than friction, but you're right sanding steel with anything that spins slower than the RAS or a belt sander at high speed is unlikely to produce sparks. You could probably get some sparks with an RO sander if you let it spin up and then hit an edge with a glancing contact but sanding flat at lower speeds is pretty safe.

 

[Curtis Hight]

Thanks everyone, and "bedankt" Alex and Rick. Kindly note that I wrote of "'half-inch thick' resin," not half-inch thick paint. Also, as I've investigated further I've discovered that Titan 2 isn't available for the RAS 115.04, only Saphir and Rubin.