[JakethePainter]

What tools and methods do you all use for removing built up rust? One of my current projects is to remove rust from I beams in an industrial setting and then coat the I beams with two coats of a rust preventative coating.

I have to bring the profile of the rusted surface down to a maximum of 5 mils. To do this i've been scraping any loose material and then grinding the beam with wire wheels to remove light rust. Heavy built up rust we have been breaking up with hammers to get to the original surface which then gets wire wheeled. This heavy rust is as much as 1/2" thick in some areas and is what is really holding up my production. Obviously heavy rust has a profile of much more than 5 mils and as such has to be completely removed.

I feel like there is a better way to go about this. This week I'm planning on trying a needle gun and if that doesn't break it up the way im hoping then ill see if an aggressive grinding disc will take it down a bit better than the hammer and wire wheel method we've been using. Anybody have any other suggestions? Thanks in advance!

 

[Rich D.]

pneumatic pin scaler is your answer

 

[TBFGhost]

flap wheel might be better then wire wheel....or maybe not...i dunno, just throwing it out there

 

[Rich D.]

Flap wheels get chewed up real quick though..

Maybe 1/4" grinding wheels ?

 

[JakethePainter]

I've got the pin scaler and grinding wheels for tomorrow. I've also got a few bristle blasters in the truck I might give a shot if I get terribly desperate. Ill try to grab a couple pics tomorrow and see which ends up working best.

 

[griz]

Try a scaling chisel in a roto hammer.

Maybe a scarifier.

With that much rust are there any structural concerns?

 

[JakethePainter]

None that I am aware of. I've seen the employees on location routinely checking the I beams, both the beams that we have finished and will be working on as well as beams we are not contracted to work on, as the project has moved closer to completion. I would assume that would be something they'd keep an eye on. Although you know what they say about assumptions...

 

[hdavis]

Knotted wire wheels and cup brushes for the finishing touches / light rust
Pin scaler for intermediate rust
Scaling chisel sds for heavy rust

It may be fastest to work down through all 3 - pin scalers will save a lot of wire brush time.

 

[painter213]

Sandblast it man! What does your spec call for? SSPC SP2, SSPC SP3?

 

[PennCoat]

Abrasive blasting will be the fastest method. However, that will increase your mobilization and clean up times, so you should double check your budget to make sure you have enough time estimated for that upgrade. If you don't have enough time to remove every molecule of rust, you can spot prime the remaining rust with Por15 . You should try to remove as much as 95% of the rust, then apply the Por15. If you remove any less, then I wouldn't consider it good practice (however I do know a few independent contractors -not affiliated with my firm- that have used Por15 on large amounts of rust with respectable results).