Stripping finish from stair treads with Festool sander / extractor

[Josef]

I’ve got a variety of Festool sanders and a CT36 dust extractor with HEPA filter installed.

Can I go to town on some older (circa 1908) finished stair treads (to get them down to bare wood) or do I need to take any ventilation or masking precautions due to the sanded finish particles?

I suspect layers of poly or lacquer. No paint and no lead concerns.

Thanks!

 

[squall_line]

Even with the HEPA filter, no extraction is 100%.  It's always a good idea to wear a mask, eye protection, and ear protection.

Without lead paint concerns, probably don't need a full bunny suit, obviously.

 

[Josef]

Will definitely wear standard PPE (eyes, ears, mask). What I am wondering is how well the ct36 does with the finish particles. I can’t find much published on how that aerosolizes into the extractor and how good the bag and HEPA are at preventing exhausting that back into the room.

Sent from my iPhone using Tapatalk

 

[squall_line]

Will definitely wear standard PPE (eyes, ears, mask). What I am wondering is how well the ct36 does with the finish particles. I can’t find much published on how that aerosolizes into the extractor and how good the bag and HEPA are at preventing exhausting that back into the room.

Sent from my iPhone using Tapatalk

The CT36 should be a full-unit HEPA certified extractor.  So the bag and filter should prevent exhausting anything down to what the HEPA certification covers, which is particles of 0.3 microns with 99.97% efficiency.
https://www.festoolusa.com/knowledge/hepa-dust-extractors#Overview

 

[Josef]

Right, but what size are the sanded particles of finish?  And are VOCs or other very small molecules released in the sanding process?

Stuff that can pass right through a HEPA?

I have no clue - I’m normally just sanding bare wood.

I know this is somewhat academic. Common sense says open some windows and wear a respirator. I’m not really “worried” more just curious about what’s really going on in the sanding and filtering process in this scenario.

Sent from my iPhone using Tapatalk

 

[cblanton42]

Sanding particles are MASSIVE to a .3 micron filter so the filter will catch all of them as long as they get sucked up and there are no leaks in your system, (the smallest dust particle you can even see is 50 microns for a reference).  VOCs are gases, you don't produce VOC's sanding.  Honestly, you're better off using a heat gun and putty knife to remove the finishes you're trying to remove, ESPECIALLY in all the corners where sanders really suck at doing their job.  Good luck!

 

[sancho57]

if they are old treds that havent been refinished inna while, you might want to check and see if they used Shellac. Just take some alcohol or mentholated spirits depending on where yer located and try it on a small area.