General Sanders, and Sander "Stroke" Related Questions

[L.Murphy]

First off-  The term General Sanders is not in any way related to Colonel Sanders or a popular fried chicken restaurant chain. In fact, many woodworking intelligence experts deny that General Sanders even exists. 

Down to Business-
I'm looking for guidance on selecting a sander. I've used dynabrade pneumatics, and a 5mm ceros. I never bothered to ask about the stroke size on the dynabrade. I'm looking for a sander to use on plywood and wood. I generally sand in the range of 120 and 220 grit. I doubt I'll ever go above 220. Perhaps, I'll occasionally drop in to the 60 and 80 grit range. However, this wont be frequent. 

My questions for you folks-
Would you recommend a 5mm or a 3mm sander?
Is there a noticeable difference in the finish left by 3mm vs 5mm sanders?
Do you have a preference between ETS and ETS EC?

Thanks!

 

[ear3]

I would go with the ETS-EC 150/5.  There is a noticeable difference between the 3mm and 5mm strokes.  The 3mm stroke will eventually get the job done, but it's best reserved for delicate sanding work, like veneers, or for high grit sanding (400 and above).  That said, I have come across cases when working with bad-quality veneered ply, where the veneer was ultra thin, where the ETS 150/5 was entirely too aggressive, and the only thing I could touch it with was the 3mm sander or else burn through the surface.

I can't compare apples to apples since I never owned the ETS 150/5 (and so can only compare the EC 150/5 with the ETS 150/3), but I would say the ETS-EC brushless sanders are superior to the normal ETS sanders in terms of efficiency.  The instant pad brake may not seem like much in the abstract, but over the course of an entire sanding session you end up picking up a fair amount of time by not having to wait for the pad to stop rotatinig before you put it down or change the paper.  Some people like the handling and the ergonomics of the older ETS sanders better, but right now I actually prefer the feel of the ETS-EC sanders.

Since you don't plan on doing any heavy duty/coarse stripping work, then the ETS-EC is probably a better choice over the Rotex150 as well.  In any case, in random orbit mode the ETS-EC is actually faster than the Rotex.

 

[Shane Holland]

I'd recommend the 3mm. For what you describe, I think it would be the better choice. You'll get a finer finish in the end.

The ETS EC is like the "premium" or upgraded version of the ETS 150 EQ. Both will do the same job at the end of the day. But, the lighter weight, the lower profile, the more powerful brushless motor, etc. offer benefits especially if you use the sander a lot.

Remember, you can always exchange or return a Festool power tool if you make a choice and regret your decision. So, get one, try it out and see if it fits the bill. If not, swap it out.

 

[Steve-Rice]

I have the ETS EC 150/3 and I can't say enough good things about that sander.  I do a good deal of veneer work and the ETS EC does a superlative job on veneer.  I've also used the 150/3 with 40 and 60 grit abrasives to remove paint and I'm amazed how well it works. To me, it's a fantastic all around sander. I actually look forward to sanding now, a job I always disliked. The dust collection is exceptional.

I don't think you will be disappointed with either the 150/3 or the 150/5.

Just my 2 cents...

 

[leakyroof]

For a single purchase, and since you have previously used that Mirka sander along with a Dynabrade, I too am going with the newer ETS EC 150/5 sander as a recommended tool.  It will more closely match the smaller bodied sanders that you've used in the past, will be lighter if you do any ceiling or overhead sanding as well.
I have owned both 150mm versions of the older ETS sanders and now own an EC 150/5 sander as well.
Both versions are nice sanders, and either 5mm version can give a good finish in higher grits as compared to the 3mm versions with proper technique and abrasive selection.
I only reach for my 150/3mm version sander if I'm doing stain-grade work or just want a smaller orbit sander in those higher grits that you said you rarely work with anyway.

 

[blaszcsj]

3 or 5 mm stroke is a personal choice. I have a 3mm stroke as I am planning to get the rotex 150/5 later down the line as funding is available to round out my sander line up and find the power and speed of sanding entirely acceptable. I will say however, the ETC-EC is significantly better than the ETS from a form/function standpoint. I much preferred the comfort and feel of the ETS-EC over the ETS. It just sits in the palm the right way and has much more power than the ETS. Just my 2 cents

 

[AlexThePalex]

If you mostly use 120-220 grit then I doubt you'd see much benefit from a 5 mm stroke. The 3 mm on the other hand would make it easier to get the fine finish you want.

 

[ear3]

Why is that?

If you mostly use 120-220 grit then I doubt you'd see much benefit from a 5 mm stroke. The 3 mm on the other hand would make it easier to get the fine finish you want.

 

[Shane Holland]

The higher the grit, the less the bigger sanding pattern/stroke matter.

Think of stroke like making big circles or little circles when hand sanding.

 

[GarryMartin]

More than you can ever want to know about sanding strokes....
http://www.buffdaddy.com/files/1519...Affects Sanding and Polishing Performance.pdf

 

[Shane Holland]

Whoa, cool Spirograph inspired contraption on that link, Garry.

And, yes, way more than I want to know. Ha.  [big grin]

 

[ear3]

But wouldn't that argue for the 5mm in the sub 220 grits?  Plus my lived experience, which is that the 5mm works much faster than the 3mm in this range, with no noticeable difference in the quality of the finish.

Thanks for the link [member=1943]Garry[/member] Martin Indeed, all and more than all I ever wanted to know about stroking.

The higher the grit, the less the bigger sanding pattern/stroke matter.

Think of stroke like making big circles or little circles when hand sanding.

 

[Shane Holland]

Edward,

Stroke is a game of compromises between the speed/rate of removal and the quality of the finish.

If you're looking for the best finish, go with the lower stroke. You can still achieve everything with the 3mm that you can with the 5mm, it may just take a little longer. The inverse is not true. The scratch pattern will always be bigger with the 5mm.

Shane

 

[AlexThePalex]

Why is that?

If you mostly use 120-220 grit then I doubt you'd see much benefit from a 5 mm stroke. The 3 mm on the other hand would make it easier to get the fine finish you want.

The bigger the stroke, the more material you remove. The lower your grit, the deeper the scratch you make, and the more material your remove. So for the fastest material removal, you combine a low grit with a large stroke.

Fast material removal -for me- is done with the grits of 80 and lower. 120 is already a pretty fine grit, and counts for me as intermediate sanding. For a lot of outdoor applications I even see 120 as finish sanding already. No need for a big stroke here, I just want a smooth finish now.

But wouldn't that argue for the 5mm in the sub 220 grits?  Plus my lived experience, which is that the 5mm works much faster than the 3mm in this range, with no noticeable difference in the quality of the finish.

The finer the grit you use, the smaller the difference you see between a 3 and 5 mm stroke. 120 is pretty fine already, so you have to look really carefully to see any difference. With stains the difference can be more pronounced than with paints. I doubt the difference between 3 or 5 mm will make you work 'much' faster in this grit and up. The finer the grit, the closer it all comes together.
 

 

[Holmz]

So where are the durabraid and CEROS now?
If they are around just get some abraidenet screens for wood and try them out?
Many swear by the abraidenet for the ETS EC as well.

I cannot say enough good things about my DEROS 150/6, and as the ETS EC is the same, then it is 'by inheritance' also nice.
However I would not use it on plywood though, I would be using my 1/2-sheet.
If you have a half sheet sander, they are usually 2 pr 2.5-mm stroke, so the /5 compliments it.

But how wrong can you go between a /3 and /5 ?
How polished up do you need the plywood?
On that buff daddy site, therevis a RUpes pneumatic with a /12 if you want mo stroke.

 

[ear3]

I see -- we just have different definitions of finer grit then  [wink]

Why is that?

If you mostly use 120-220 grit then I doubt you'd see much benefit from a 5 mm stroke. The 3 mm on the other hand would make it easier to get the fine finish you want.

The bigger the stroke, the more material you remove. The lower your grit, the deeper the scratch you make, and the more material your remove. So for the fastest material removal, you combine a low grit with a large stroke.

Fast material removal -for me- is done with the grits of 80 and lower. 120 is already a pretty fine grit, and counts for me as intermediate sanding. For a lot of outdoor applications I even see 120 as finish sanding already. No need for a big stroke here, I just want a smooth finish now.

But wouldn't that argue for the 5mm in the sub 220 grits?  Plus my lived experience, which is that the 5mm works much faster than the 3mm in this range, with no noticeable difference in the quality of the finish.

The finer the grit you use, the smaller the difference you see between a 3 and 5 mm stroke. 120 is pretty fine already, so you have to look really carefully to see any difference. With stains the difference can be more pronounced than with paints. I doubt the difference between 3 or 5 mm will make you work 'much' faster in this grit and up. The finer the grit, the closer it all comes together.

 

[Steve-Rice]

Ed's got a great point regarding what is "fine grit". 

For most go my work, I start at 150 and go up through 180, 220, 240 & 320.

 

[Scott B.]

When choosing between 3mm and 5mm options, personally I choose the 5 when in doubt. It is easier to get fine work out of a slightly over stroked motor than to go lower grit in a short stroke.

I was on a similar journey today...reminded myself that 80 grit on a Rotex is quite faster than 60 grit on a ETS 5mm.

 

[L.Murphy]

Thanks again for all the information. I think I am going to go with the 5mm. I have a dewalt d26453. I'm not sure of the stroke size on that model, and it is discontinued. The newer dewalt variable speed ROS is listed as having a 3/32 stroke, which is roughly 3mm. I figure purchasing a 5mm will give me increased efficiency in lower grits if nothing else. It also leaves the door open for a purchase of 3mm Festool sander further down the line. 

Follow up question-
Would you folks recommend the use of a "hard" backer pad for Table Tops? Softer Pads seem to be marketed as usefull for contoured surfaces.

 

[grbmds]

For me, on my 150/5, the hard pad works great and is a great assist to keeping the surface being sanded flat, even on smaller surfaces than table tops. I would recommend it.