ETS 150/3 or ETS 150/5 - the definitive answer?

[Mettes]

I had the chance of taking a workshop "spraying H?O based finishes".  Learned some very interesting stuff.

There where representatives of 3M, Festool, Rupes and Zweihorn.  Rupes makes sanders and dustextractors, high quality stuff just like Festool and Zweihorn is a part of the Akzo Nobel group and they make paint and clear coat.

They all had there toys with them, and we got to play around with them, when the question came which one to choose the 5mm or the 3mm, they were unanimous: 5mm

Let me clarify.  We're talking about finishing wood.  If you use the same grid on both machines the swirl marks will be equally deep they will just be further apart from each other.  When we are talking about wood, which normally gets a coating thickness of 100-150 microns, they will give exactly the same result.

Why then choose the 5mm, the paper will last longer and you get a better dust collection.

We of course tried both sanding techniques before spraying and the panels were identical in finish and gloss.

In the automotive industry thats a different story because they work with much thinner layers.

What do you guys think of this?  Does it make any sens?

 

[gearup75]

    Darn, guess I will have to get the ETS150/5 to go with the ETS150/3 to save paper now

 

[Daviddubya]

Thanks - the information is interesting and confirms what I have read in lots of discussions.  Many people cannot tell the difference between the finish produced with a /3 and a /5 sander.  I will keep what I have since I am fortunate to own a 150/3 and a Rotex with a 5 mm stroke.  The sandpaper lasts long enough!   

 

[mwhafner]

The sandpaper lasts long enough!

I have the same setup as David W, and wouldn't change. 

Having said that, I also agree with the premise of the post.  If you are using a "coating" finish, then you have a margin of error, especially if sprayed.  Some of my projects are finished only with oil, and the results with the 150/3 are amazing.  I am not convinced that I would get the same with the the 150/5. 

I have no complaints with either the dust collection or life of the sandpaper of the 150/3

 

[gearup75]

    Sorry, I wasn't thinking clearly and made a sarcastic comment.  I come from the automotive world.  I use to own a body shop, and sandpaper was a major consumable.  I find the Festool sand paper less expensive and longer lasting then 3M or Mirka.  I used dust extraction then also but nowhere as good as what Festool affords.  And yes, I am tempted to attempt a vehicle paint prep job with my newly acquired Festool  system even though I no longer do cars.
    I also have the ETS150/3 and the RO 150.  I prefer the RO 150 for rough cutting and the ETS 150/3 for finishing to 320 grit.  In my experience, limited that it is,  the RO 150 is too aggressive for finish work.

 

[tbellemare]

You can take a Rotex 150Rotex 150, (with a 5 mm stroke), and go from a rough piece of wood to a polished surface in a few minutes. It's a common demonstration. I've never tried it on auto paint but I am about to on my own car because I got a scrape and run at a store parking lot.

The gear-driven mode is used at the beginning of the demo mentioned above to clean up the roughness and at the end to polish. The RO mode is used in between. Logically, the RO part can be handled with an ETS 150/5 or ETS 150/3.

I'm pretty sure that people that find the Rotex 150 or 125 hard to use for finish sanding are fighting the sander or haven't figured out a good way to hold it. I tend to hold it by the hose connection and let it "float" around the work piece on a horizontal surface. An alternative way that works for me is to hold it by the "horn" with one hand and hold the hose with the other, which is a lot like how the ETS sanders are held. That is also how I tend to hold it on vertical surfaces. With any of these sanders, the weight of the hose needs to be neutralized so that the pad and paper aren't trying to "dig in" on that side.

Tom

 

[nickao]

Anything above even 180 you are better off using the 150/3.

I see no reason to ever go more than 220 on wood. I know people go crazy and sand and sand and it just closes the pours and changes the wood color. To me I go to 150, finish than sand the finishes with 220 and I could see myself. For a car or metal of course you need go to finer grits, much higher.

So on wood I do think there is a need for the 150/3 in addtion to the RO150 as I am not puting that RO 150 on any clear finish after it is applied. The 150/3 just is better for that purpose and better than the RO 150 on anything above 180 in my opinion.

The 3mm stroke simply makes a difference above 180 and that is where I see the 150/3 excell over the RO150 for fine finishing. Same goes for the 150/5, at 220 you will see the 150/3 is better. Much less than that and I really can not tell any differnce at all so I sold my 150/5.

Use the RO 150 up to 150 or 180grit and switch to the 150/3 at 150 to 220grit and up and you will get awesome results.

 

[gearup75]

O.K.....I have done a few steel test panels  using  the Rotex 15, the ETS 150/3 for the prep work.  Unfortunately, I can not seem to capture the results in a picture that the only naked eye can see.  However I feel I can share my experience with you and the results.
    First, I made a few 18'x30' steel panels and rolled them to about a 60" radius so they have a smooth curve to show the finish and light changes easier.  Being smooth metal and wanting to test sanding properties, I treated the metal with DX-579 metalprep and sealed with DP-40/DP401 epoxy primer system and let dry overnight with a nice wet coat of Urethane surfacing primer after the proper flash times.  This is the normal procedure on automotive repairs anyway and I wanted to duplicate it.
    Now the fun part, finish sanding with my Festool sanders. I did one panel with the Rotex, one panel with  the ETS150/3 and one panel using both  because I could.  I  also  started at 320 grit and finished with 400 grit.  I did finish one of the panels with the S500 grit platin to simulate the 500 grit normally used before a metallic basecoat/clearcoat system.  I need to state that the 500 grit sanding I usually do by hand with a soft pad and wetsanding to prevent swirl marks from appearing in the finish product, even years down the road.  One thing I have found over the years, swirl marks even invisible to the eye before clearcoat  can align the metallic flakes and show after the clear is applied.
    The results were better then I thought they would be.  there were some slight swirls in some areas with the panel finished in 400 grit and the Rotex.  Maybe not enough to be seen by the untrained eye, but they were there.  The panel with the Rotex and the 500 platin though, had no  swirls in the finished product.  Impressive IMHO.  The panel finished with the ETS15/3 and 400 grit  had less noticeable swirls and would have been acceptable for a single stage paint job, as in no clearcoat.  I saw no swirl marks with the platin on the ETS.  This may be the way to finish prep production bodywork.
    As a side note, I had the CT22 turned down pretty much all the way to prevent swirls and really enjoyed the dust extraction over any of the methods I have tried  in the past.  I was surprisingly less dusty by the end of the day.
    Now  I am tossing the panels on the roof of the shop and will take a look at them every once in a while for the next year to see the long term effects on the finished product.  Something I always do when testing new products before I pass it on to customers.
    Maybe next weekend I can perform the same test on wood panels ;D
                                                                  Carl

 

[Notorious T.O.D.]

As Nick said I rarely sand past 150 or 180 grit if using a film finish or a stain or analine dye.  I took a finishing class with Jeff Jewitt back about '94 or so and I believe it was he who said that he human eye can't see the individual scratches made by grits higher than 180.  I generally agree with this statement although I think on some very dense and hard exotic woods there can be differences from the wood that commonly use for our projects, oak, cherry, poplar, etc.

If I am finishing with paint I would go to 120 machine sanding.  I believe that when machine sanding someone told me that 120 machine sanded is like hand handing with 150...ie one grit higher.  I don't know that it is a fact or not but it seems to make soe sense.

I remember probably 15-20 years ago a friend who was fairy new to woodworking built a table and chairs for his kids out of maple and sanded them to like 320.  He was more used to working on car finishes...  He tried to stain the set and it would not take stain at all....wipe it on and wipe it off.  He called me up and wondered what he could do to save the project.  I told him to go back to 150 grit with the sanding and to perhaps go to an analine dye rather than his Minwax stain.  He resanded and ended up using his Minwax and it all truned out nice but he learned that if you sand wood too much you burnish the pores closed and that is fine if you are using an oil finish but not so good for stain and film finishes....and you can waste a lot of time oversanding.

I also find that in 90% of cases the lighting we are working under is much brighter than the light the object will be normally viewed under.  The exception can be if the piece will be in direct bright sunlight which is very bright and will show every flaw.  But it is worth consideration to thing about the level of lighting will be where the piece will ultimately live.

Best,
Todd

 

[tbellemare]

That's a really good point about the lighting, Todd.

My assistant, with my guidance, sanded a coffee table in place in our living room. It was 25-year old solid oak and had been quite abused. The sanding was done at night, under artificial lighting. It looked perfect when she was done. It got about 12 coats of polyurethane over the next few evenings in the shop, again, artificial light.

'Took it back to the living room in the evening, it looked quite nice. 'Opened the blinds the next morning and looked at it with a shallow viewing angle. It didn't look quite even. DARN!

Tom

 

[Notorious T.O.D.]

Yes, in my previous 2 car garage shop I had 4 8ft 2 tube high output flouresent lights....my buddy referred to it as the "Surface of the Sun".  It was that bright and I am not sure shadows could exist there...lol

I know I have spent hours over the years filling and fixing pin holes in the surface or the finish that when the piece was installed and delivered you would never see if you got down on your hands and knees and looked for them.  I think this is what separates so much of the furniture of today from the Townsend Goddard masterpieces of 250 years ago...they knew how to put the effort into what shows and spend little time on the backs, insides and undersides that don't really show.  It was a very different yet very practical standard and I am sure it helped them make money too.  Today, I am aftaid to many of us suffer from the need to have each and every surface sanded to perfection even though many of them will rarely be touched or even have someone glance their way.

I think it has something to do with our perceived perfection of mass production.  Yet, if you go to the furniture store you will see that the standards they build to are in many ways even looser than Townsend and Goddard built to 250 years ago.

So, who among us are overbuilders?  Of course the stuff in the stores will be lucky to avoid the city dump for 10 years so that may be a factor too.
But I still think there is a lesson in us thinking about this practice a little more often...

Best,
Todd

 

[monte]

Anything above even 180 you are better off using the 150/3.

I see no reason to ever go more than 220 on wood. I know people go crazy and sand and sand and it just closes the pours and changes the wood color. To me I go to 150, finish than sand the finishes with 220 and I could see myself. For a car or metal of course you need go to finer grits, much higher.

So on wood I do think there is a need for the 150/3 in addition to the RO150 as I am not puting that RO 150 on any clear finish after it is applied. The 150/3 just is better for that purpose and better than the RO 150 on anything above 180 in my opinion.

The 3mm stroke simply makes a difference above 180 and that is where I see the 150/3 excel over the RO150 for fine finishing. Same goes for the 150/5, at 220 you will see the 150/3 is better. Much less than that and I really can not tell any difference at all so I sold my 150/5.

Use the RO 150 up to 150 or 180grit and switch to the 150/3 at 150 to 220grit and up and you will get awesome results.

I have to agree with everything Nick just mentioned. (Dang, it seems as if I said that line before)

when it comes to wood,,,,,,,  cast resin now is a different matter, but would be veering off the course of this thread.

One thing I'd like to add when doing flat work with the ETS 150, if your using the stock pad that came with it,

go out and splurge on the hard pad..... http://www.festoolusa.com/products/sanders/pads/stickfix-sanding-pad-hard-484850.html

I find it much better working on the field as well as when coming out to the edge of the work at hand.

cheers,
Roger

ps. keep in mind that the hard pad for the ETS150 has a little more give that the hard pad for the ROTEX 150, . . . a good thing.
. . . Also if you happen to have the older model RO150 (with the attached cord)........the hard pad for the ETS150 could also work on it.

 

[gearup75]

    I guess I forget this forum focuses on wood more then metal. My mistake.
                                              Carl

 

[mwhafner]

    I guess I forget this forum focuses on wood more then metal. My mistake.
                                              Carl

I don't think that your tests were without merit.

 

[tbellemare]

I don't think this forum is just about wood (maybe I'm wrong?). I find it quite interesting to hear from people that use Festool products in a different way than what others might. The tools lend themselves to use in wood but they are useful for a variety of materials. The evidence is clear in Festool's own literature and the design of consumables.

I grew up having to take care of several cars, even before I could drive. I like to hear from people that use Festool products to care for or rehabilitate cars.

There is an entire series of Festool products that are very little heard of in the U.S. that are generally related to the auto body shop. The Festool air tools, though not talked about much on this forum, have great value also. There is a certain amount of art that is needed to do body work right and those artistic ones can benefit from proper dust collection at least as much as a woodworker.

Tom

 

[AlexThePalex]

In the automotive industry thats a different story because they work with much thinner layers.

What do you guys think of this?  Does it make any sens?

I grew up in an auto body shop, my father had one and I was destined to take over when I was old enough. Unfortunately this scenario didn't work out because he went broke just 1 or 2 years before I was old enough to take over.

Thin layers indeed. 80 micron was the standard for normal cars. 

We mostly worked with electric Rupes eccentric sanders, and they all had a 5 mm swing. We used 3M paper of 120 for rough sanding and then finish it off with 240 grit. Not higher. For general body work I mean, on good surfaces.

When an area was damaged on the other hand, after remodeling and panel beating, we did the rough work with the electric sanders but after applying filler and the first layer of primer we used a large air sander by Rupes, like the Festool LRS 400, and a smaller type like the LRS 93. And a lot of hand sanding of course. This was for WET sanding and then we would work our way up from 240 to 400 to 800 to 1200 grit. This would leave a very smooth almost mirror-like result.

We always used Rupes tools and they were very good. Also some by Elu and Makita. If I had the body shop now, I'm sure I would have tried out the Festools line too.