# Forum Home Renovation Painting  Angle grinder or vertical grinder for sanding weatherboards

## arod

I've read up on the forum regarding all the different methods for stripping weatherboards and have decided machinery is the best way to go for my situation.  
I'm looking for advice on whether it is best to use a standard 100mm or 125mm angle grinder with 24 grit discs to do this, or am I better off investing in a vertical grinder (for example: GV7000C-180mm Disc Sander).  
The vertical grinder obviously has much larger discs for a similar weight, which would have the benefit of presumably being quicker and also making it harder to gouge.  
Can anyone give some advice on which would be better to use? 
Thanks

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## BLWNHR

You don't want to use an angle grinder for a sanding disk, it spins way to fast. 
The disk sander you linked to spins at 2,500-4,700rpm.
The SA7000C sander which looks like an angle grinder spins at 0-1,500/4,000rpm.
An angle grinder by contrast spins at 11,000rpm.

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## arod

Can you recommend which one you would use for sanding weatherboards between these two sanders?

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## manofaus

whats wrong with a heat gun and scraper?
I have found that If you use a flapper disc in an angle grinder it produces marks in the timber as if it was rough sawn.

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## aroma

G'day, I'm Roma.   I'm using a heat gun and scraper and it is going to take me till I die!   I think it's acrylic paint, some parts come off clean but other places yellow gunk left behind, won't budge.

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## prof_montoya

What about a small belt sander?  Are these not practical/ useful?

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## stevoh741

Why strip them? Why not touch up any dodgy areas and just repaint?

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## amiaow

I wouldn't go near sandpaper on an angle grinder- I tried this on our boards at 80 grit and it ripped them up. Our boards are pine though so you might have better luck if yours are hardwood. Creates a heap of dust. Don't try if paint is old and might be lead- you don't want that all over your yard. 
I have tried a few things recently to see the best method to strip the paint. It is failing in many places so needs to come right back to bare wood. I've tried- 
Josco 'Brumby' strip disc on angle grinder- good, but discs don't last forever and makes heaps of dust
Paint stripper- pretty hopeless on lots of coats of paint (60 years worth in our case) and needs sanding after scraping anyway
Heat gun and scraper- winner, takes longer than both other methods but right back to bare wood. I'm going to put in the hours (and hours) and do this to the house and then paint it in Weathershield. 
Here is a pic of three methods together- from L-R: strip disc (only took off some top coats), paint stripper & scraper (only took off top couple of coats, would need to reapply) and then heat gun & scraper.   
Hope this is useful!

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## manofaus

a wise freind of mine invested in 6 heat guns and scrapers, he then had a BBQ with his mates, took them a few weeks but they got it done

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## amiaow

I did some house stripping/sanding over the weekend. Stripping with the heat gun takes ages but I am choosing this method on the west-facing back of the house where the paint has failed. I discovered that the front of the house has twice as many coats as the back of the house and it is stuck quite nicely still. It took me about an hour to strip a 40cm section of one board- ridiculous! So on the front of the house I used the Josco strip-it disc to remove the surface acrylic coat (the house is crackled acrylic with no undercoat over enamel (many coats) over lead base coats) and any other bits that wanted to come off. It is nice and fast and gives a good, smooth result. I used two strip-it discs to do one section and I think I will probably use another three to complete just the front of the house. So it's a bit expensive, but much cheaper than the house sanding man and much faster than the heat gun & scraper.

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## handy man

I used a makita sander polisher 7 inch to to the weather boards on my bungalow . A 24 grit disc will leave marks like rough sawn timber but I like that look and only took a few hours and 3 discs from memory  I think its the way to go If you have multiple coats of paint. A word of warning if you have never used a large grinder I suggest do some practice on some scrap first they can be dangerous  and can leave gouges in you timber very quickly.
  peter

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## min015

We've just about finished out chamferboard/weatherbeeta house and have been using the strip discs on an angle grinder. It's taken it back to bare wood in places where the paint was flaking and needed to come off. We've been through quite probable 20+ discs at $12 each but and wasnt really aware of any other 'cheap' alternatives. In places where the paint wasn't peeling and just needed a light sand before painting over the top, we used a normal sander (just a rectangle of sand paper that the machine moves back and forth). We also have a scraper like thing, with a Tungsten blade in it, which has been great for peeling the flaking paint before sanding smooth.  It's taken ages...but we're nearly finished...then on to sanding the gutters and metal balcony balastruding.

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## Steffen595

1person 1 week heat gun, no idea why others took weeks. Then get orbital sander with zircon disks, those blue or green fabric ones. Angle grinder and grid 80 flap wheels can leave nasty marks and sometimes caused residual paint to burn/melt to black sticky stuff and clogged up. 
Then master prep, undercoat, 3 layers acrylic. Looks nice for 2 years now. And gapfiller inbetween. 
Why stripping it back? Then you see some boards need replacing.

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## Sapainting

hey all   
paint stripping is by far the worse of all painting demons lol. but it is necessary for a good job.  
before you start stripping anything on an older house you should be using a lead test kit. If lead is present and your using a heat gun then your releasing the lead fumes and damaging yourself up!  
i reckon the power sander is the go Not an angle grinder it will wreck your weather boards all together. Our company uses the same makita power sanders with 80 grit and 60 grit disc then finish it off with a 120 grit disc comes up great the only problem is the dust and lead. for the dust if it isnt lead here is a link of these great respirators   Respirators 
they are full faced ones so the dust doesnt get behind your sunnies. if the house is lead based you will have no choice but to encapsulate the hole side of the hole where your going to sand so that the dust doesnt go into your neighbours yard kill the cat, make the kids sick and so you dont get sued. another great tool is called a Linbid scraper cannot prep a external or repaint with out one   BUY Linbide General Purpose Scraper $15.34 /Scraper at Painting Tools Online Store 
hope this helps some 
Glenn S & A Painting

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