Sanding Wrought Iron Railing

[Bob MN]

I'm planning on repainting the railings around my porch. There is light rust and i was planning on using my RO90 to clear the rust. What abrasive would work best? 

 

[Roseland]

Wouldn't a wire brush in a drill be quicker?

Andrew

 

[Bob MN]

Wouldn't a wire brush in a drill be quicker?

Andrew

Probably, but I kinda wanted to use my RO90. 

I might end up going the wire brush/drill route.

 

[leakyroof]

If the rust was just really light scale, VLIES might work. Otherwise, you're probably going to end up using Granat since Saphir isn't made in the RO90 size if I remember correctly, and Rubin 2 is best for bare wood or a non-finished surface that something like paint or clear film finish would clog it with.
The Granat will resist clogging, and stay sharp, and you can get it in the Delta shaped section to reach tight spots of the fence/railing with your Delta Head on the sander if needed.

 

[Michael Kellough]

3M Scotch-Brite General Purpose Hand Pad. Amazon

 

[Cheese]

I was going to suggest Vlies in 80 or 100 grit, but then I noticed Festool no longer offers Vlies for the RO 90. [sad] [crying]

 

[leakyroof]

I was going to suggest Vlies in 80 or 100 grit, but then I noticed Festool no longer offers Vlies for the RO 90. [sad] [crying]

  You're kidding, right?  Wow, wonder if they had too slow of sales compared to the larger 150mm version.... [blink]

 

[Cheese]

You're kidding, right?  Wow, wonder if they had too slow of sales compared to the larger 150mm version.... [blink]

Wish I were...actually, Festool offered Vlies for all of their sanders at one point. Including the RAS, DX, DTS, LS & RS sanders, now it's only available for the 125/150 models.

RIP...MFS, aluminum cutting blades, spark trap, PCD blades, Vlies...

 

[McNally Family]

Wouldn't a wire brush in a drill be quicker?

Andrew

When I was in the Navy many years ago, removing rust was a full time job.  We used paint chippers, wire brushes, grinders and a lead-based primer called "redlead".

The most important factors were to not only remove all rust, but any moisture, oil, or other contaminants such as dirt, before priming.
 
As for which technique was used, I believe sandblasting was considered the best, but due to the obvious mess it left behind, was not very practical when working aboard the ship, outside of a controlled environment such as a shop.

In regard to which Festool sandpaper would be most effective, I think any low grit paper would work (the lower the grit the better), with the goal of getting as close to the effects of a wire brush or wire wheel as possible.  To prevent the return of rust, prep is critical, or you will simply be inviting the rust to return.

I am considering the purchase of the RO90, but more for polishing purposes (think both wood finish and plastic headlights).  Of course, this involves the opposite end of the grit scale.

 

[leakyroof]

You're kidding, right?  Wow, wonder if they had too slow of sales compared to the larger 150mm version.... [blink]

Wish I were...actually, Festool offered Vlies for all of their sanders at one point. Including the RAS, DX, DTS, LS & RS sanders, now it's only available for the 125/150 models.

RIP...MFS, aluminum cutting blades, spark trap, PCD blades, Vlies...

. Yeah, I have the spark trap, bought it when I had my CT-23.
Did NOT realize Vlies used to be so widely offered among the Sander Line... [huh]

 

[mkasdin]

Grinder with a variable speed and a wire disc. Or emory cloth, or steel wool is good by Hans since they conform to the shape
The above poster mentioned the scotch brite pads. They come in many grits so this is also an option, since its surface rust.

 

[Klemm]

I hate to recommend something other than a FESTOOL based solution but I need to share my successful experience at the end of many not-so experiences:

3M ScotchBrite started offering a combination ceramic/aluminum oxide abrasive encapsulated in plastic.http://solutions.3m.com/wps/portal/3M/en_US/3MIndustrial/Abrasives/Products/~/Scotch-Brite-Radial-Bristle-Brush?N=7581714+3293242167&rt=rud#variantView
I have used this type of abrasive in another version fitting  the threads on my Milwaukee 4 1/2 angle grinder.
It flexes and follows contours. It does not load (!) up at all. Leaves the metal smooth and bare shiny and ready for etching / priming and coating with your finish.
if desired I will go find my abrasive and submit a picture. Last time I used it to de-rust a just purchased used and badly abused, cast iron band saw table with rust, paint and glue residue.
Hans

 

[Klemm]

I hate to recommend something other than a FESTOOL based solution but I need to share my successful experience at the end of many not-so experiences:

3M ScotchBrite started offering a combination ceramic/aluminum oxide abrasive encapsulated in plastic.http://solutions.3m.com/wps/portal/3M/en_US/3MIndustrial/Abrasives/Products/~/Scotch-Brite-Radial-Bristle-Brush?N=7581714+3293242167&rt=rud#variantView
I have used this type of abrasive in another version fitting  the threads on my Milwaukee 4 1/2 angle grinder.
It flexes and follows contours. It does not load (!) up at all. Leaves the metal smooth and bare shiny and ready for etching / priming and coating with your finish.
if desired I will go find my abrasive and submit a picture. Last time I used it to de-rust a just purchased used and badly abused, cast iron band saw table with rust, paint and glue residue.
Hans

just found the item:
'https://www.zoro.com/scotch-brite-bristle-disc-45-in-dia-34-in-trim-80g-24242/i/G1290161/?gclid=CjwKEAjwgo6_BRC32q6_5s2R-R8SJAB7hTG-4V_m0rfq1QbOU9o2M60M2LYu-ZlipbJ25qm1tY5WKRoCG4jw_wcB&gclsrc=aw.ds
SCOTCH Brite Bristle Disc is using an abrasive offered in the disc version shown on the link, also in smaller diameters to fir the ROLOC style 2 inch discs on an air angle grinder and all kinds of other configurations.
If your time and the end result means anything, you'll go this route.
I bought my first one at SEVENTH CORNER HARDWARE in St Paul. Bob, you know Chuck Reese never recommended anything that didn't work (miss that place... and their experts)
Hans

 

[Cheese]

I bought my first one at SEVENTH CORNER HARDWARE in St Paul. Bob, you know Chuck Reese never recommended anything that didn't work (miss that place... and their experts)

Hans...we all miss Seven Corners Hardware, it was the bulwark for our woodworking, metalworking and most of our other niche market needs.  [sad] [sad]

 

[Stephen B]

[member=434]Bob MN[/member] Good luck with this, better you than me!  [big grin]

Another product from 3M which could be used either alone or in conjunction with the 3M Bristles suggested by TSO is this paint and rust removal disc.

If the railings are wrought iron or have intricate decorative elements I would also buy a wire brush and some 80 and 120 grit emery paper sheets.[size=11pt] [If they were originally  galvanised steel rather than true Wrought Iron I would only pretreat where rust has occurred.]

[attachimg=1]

True redlead  paint as mentioned earlier is banned in Australia, probably because it CONTAINS LEAD!  [eek]

Suggest that if you are stripping it right back that you use a 3 step re-coating process, similar to this one distributed by WhiteKnight in Australia with Rust Converter - Undercoat - Topcoat (s).http://www.whiteknightpaints.com.au.../rust-guard/?gclid=CKKViNbipM8CFQujvQodRloF_Q

Have a look at the video in this link. You might not  like the fact that he hand sands the wrought iron fence!  [smile]

________________________[size=8pt]

Disclaimer - I work part time in hardware sales including at times the paint department.

 

[Tim Brennan]

Would phosphoric acid be a good solution to treat the rust? Have a similar job myself

 

[Stephen B]

Would phosphoric acid be a good solution to treat the rust? Have a similar job myself

[size=13pt] [member=21939]TBR[/member]
Ingredient in many brand name commercial rust converters. Also in many soft drinks/soda pop to give that tangy taste.  [eek]

 

[AlexThePalex]

It is not one or the other, you use both a grinder with a wire brush and a sander to prepare this for painting.

First the wire brush to remove all rust spots, this needs to be done very thoroughly or it will return after a while. And then you sand it all flat with the RO90 using 80 grit & 180 Granat or Brilliant paper.

If you have access to sandblasting that's even better, but not something the typical home owner has lying around.

 

[Big G]

use a needle scaler, Hilti TE104 for example and one good coat of Hammerite, leave your Festool DIY sanders in their boxes.

 

[bobfog]

use a needle scaler, Hilti TE104 for example and one good coat of Hammerite, leave your Festool DIY sanders in their boxes.

Wouldn't call Festool sanders "DIY", but your suggestion of a needle scaler is a good one. For a one off job they can be bought very cheaply and will do the job, rather than springing for the Hilti.