Sanding between finish coats: by hand or powertool?

[QuailRider43]

I'm trying to poly varnish a workshop countertop to practice my finishing skills, and quickly coming to the realization that (a) I hate finishing, (b) I hate hand sanding.  After first coat of poly, I got lazy and decided to just use 320 grit in my old 5" random orbit sander (still saving my pennies for that fancy Festool sander collection).  I very quickly sanded right through the first coat of varnish I had applied (which is just as well, as I wasn't happy with it).  Next time I'm going to try an oil/varnish blend or a wipe-on type poly which will be more forgiving to apply, but I'll still need to sand between coats.  So I arrive at the main question: do people use their sanders between finish coats on large flat projects, or bite the bullet and hand sand everything between coats?  Can a 5 mm stroke sander work here, or is this only the realm of 3 mm stroke finish sanders?

 

[Steve-Rice]

I hand sand using this Mirka hand sanding block with 600 grit Abranet abrasive and my CT 26 dust extractor.  It works great and there's no dust residue.  Just a couple of quick passes and your done in no time at all.  Leaves an extremely smooth surface.  I sand after the last coat as well.  The sanding block only costs about $20.  I use it on every project.

I wouldn't use my ETS EC 150/3 because it's just too powerful.  I'm guessing it might be OK to use if you used a very high grit abrasive (such as 1200 or above) and turned down the speed (but, honestly, I'm just guessing here).  But, since the Mirka sanding block and the 600 grit Abranet work so well, I'll just stick with that.

 

[Cheese]

I always hand sand between coats. I use 320/400 very, very lightly because it's easy to remove what you just applied. You just want to knock the dust nibs down.

 

[Holmz]

I hand sand using this Mirka hand sanding block with 600 grit Abranet abrasive and my CT 26 dust extractor.  It works great and there's no dust residue.  Just a couple of quick passes and your done in no time at all.  Leaves an extremely smooth surface.  I sand after the last coat as well.  The sanding block only costs about $20.  I use it on every project.

Adjustable stroke, brushless, and lifetime guarantee on the motor.
Should take long to save up the $20.

 

[tjbnwi]

Power sand with the ETS 125. Very little hand sanding.

Normally I use 320 Granat.

Tom

 

[JimSpence]

Power sand with the ETS 125. Very little hand sanding.

Normally I use 320 Granat.

Full speed (6) ?  Or slow the sander down ?  Like OP, I'm afraid of stripping the good stuff.  Have ETS EC 125.

 

[tjbnwi]

Power sand with the ETS 125. Very little hand sanding.

Normally I use 320 Granat.

Full speed (6) ?  Or slow the sander down ?  Like OP, I'm afraid of stripping the good stuff.  Have ETS EC 125.

Large flat surfaces speed 6, small areas around 4 maybe 5. 1,2 & 3 can be jumpy if you're not careful. CT is set as low as it goes.

I do not have the EC mine are the older ETS 125's.

You'll burn through a few finishes before you get the hang of it.

Tom

 

[QuailRider43]

3 mm or 5 mm stroke?

 

[w802h]

The RTS shines here with a 2mm stroke.  I also use the HSK hand sander.  I think a 5mm stroke is too aggressive.  You're more likely to burn through the finish.

 

[semenza]

3 mm or 5 mm stroke?

  If the choice is between 3 or 5 , then 3.  I am a fan of the ETS150/3 for sanding between coats.

  I generally apply two brushed on coats before sanding to help prevent sanding through. Also, if you go with wipe on, you will likely have thinner coats and be more likely to sand through.

Seth

 

[bdiemer]

I'm lazy. I too use a power sander between the coats. I have an ets 125 dedicated for that very purpose. It's light weight and has a slight stroke. The hardest thing for me to learn was to be patient between coats. Find something else to do.

 

[tjbnwi]

3 mm or 5 mm stroke?

My ETS 125's are 2 mm stroke.

As bdiemer mentioned patience is a must.

Tom

 

[#Tee]

I like to gently stroke it with my hand [eek]

 

[sancho57]

I use water base products in the states so 1st raise grain,,Hand sand to knock the nibs down, apply 1st coat Power sand with RTS400 lightly with 320 - 400 , 2nd coat depending on how the finish turned out but usually hand sand 320 - 400 foam backed sand lightly, then final coat..

 

[Holmz]

Festool also have a hand sanding block like the Mirka.

It depends on what "sanding" means. Taking the high spots off, and providing some key/tooth is not the same as removing bulk material.

For proper sanding a sander is faster. For delicate scuffing up, the hand sanding can be better. Much of the job is getting the materials out and put back. The actual handiwork is stroke and look, stroke and look.

 

[Steve-Rice]

[member=40772]Holmz[/member] Yes Festool has an almost identical hand sanding block, but instead of $20, it's close to $70.

That makes no sense to me whatsoever...

 

[Holmz]

It is a system. [member=29138]Steve-Rice[/member]

I am not sure of the size of the FT block but there is more thank everyone size of Mirka block. The one I have is different from their 1/2 sheet size... I should see if there is a hand block version of the uva115e size and then I can get rid of the smaller one.

In any case it is harder to burn through a thin layer by hand, and one really has to try hard to do it compared to using a power tool.

 

[Steve-Rice]

[member=40772]Holmz[/member] - Just for the record, the Festool hand sanding block is only slightly larger at 80mm by 130mm, whereas the Mirka hand sanding block is 70mm by 127mm.  Certainly not a difference worth three and a half times the price.

Just sayin'...

Oh, and by the way, the Mirka fits perfectly on the Festool 27mm hose.

 

[JonSchuck]

[member=40772]Holmz[/member] - Just for the record, the Festool hand sanding block is only slightly larger at 80mm by 130mm, whereas the Mirka hand sanding block is 70mm by 127mm.  Certainly not a difference worth three and a half times the price.

Just sayin'...

Oh, and by the way, the Mirka fits perfectly on the Festool 27mm hose.

I don't understand this.  The picture shows a Festool hand-sanding block with what looks like a Festool 27mm AS hose.  But that hose is too big for that sanding block.  That sanding block fits a gray 21.5mm (if I remember correctly) non anti-static hose.  Seth did a review on it a few years ago which was brought back recently.  That 21.5mm hose is super.  It is way lighter and more flexible than the 27mm one.  Seth also showed that it is very tough.  It is also long (I think 5 meters).  I have been using it a lot lately, along with 2 interface pads, trying to restore an old airplane.  The Festool sanding-block may not be any better than the Mirka one but that hose is worth every penny.

 

[flair woodworks]

I use Festool's foam-backed Granat, by hand, for sanding between coats.

The Festool sanding block, equipped with the 21.5 mm non-antistatic hose is by far the most ergonomic sanding block/dust extraction combo.  It does come with an adapter for use with a 27 mm hose, but I would not recommend using it with the green antistatic version, as it just has too much fight for the weight of the sanding block.

By the way, I have the Mirka block, which fits the 27 mm hose, but I rarely bother connecting it because it's awkward to fight the hose.