Welding Prep and Excess Weld Removal

[JonnyAlpha]

Hi;

Probably been covered numerous times, can anyone recommend a method for removing excess welds.

The welding is on an old mini and I need tips for removing excess weld in preparation for painting foot wells and floor internally with probably hammerite (so doesn't need to be mega smooth) and externally on bodywork so needs to be smooth.

Also is a flap disc best for preparing a weld area and if so which grade and make.

I had a flap disc for my Bosch Angle grinder to try out but it got filled up with old underbody seal (what's the best way to remove this).

What are Zirconium discs like?

 

[gordon stephenson]

For quite rapid metal removal I use a 5" 40 grit zirconium flap disc, works really well. For cleaning after clogging I use a piece of hard plastic/nylon etc,pressing quite hard and running it across the grinding face,

 

[tux]

What Gordon said. ^^^
Flap discs are the future IMHO. The zirconium ones tend to last a good deal longer than the aluminium oxide ones in my experience.
Best to remove underseal before using an abrasive, a heat gun and scraper works well, then clean up the gooey mess left behind with rags and white spirit.

 

[mrcheese]

I did a load of weld dressing using a standard grinding disc before moving to flap discs. So much better. Faster and with a better finish. Some of my welds can now be almost invisible!

 

[Chickenjohn]

I use a Zirconium 36 grit abrasive disc on a pad as well for weld dressing! Works great on convex and flat surfaces, Not so easy where the area is concave so I also keep a grinder with a grinding disc handy as well.

For really tight spots a 10mm belt "finger" sander gives great results too!

 

[pedrobedro]

I use a flexible backing pad and fibre disks available in many grits for fetching welds down. It works out a lot cheaper than flap disks and they are a lot kinder to the finish than grinding wheels.

 

[cumbriasteve]

personally I would not use Hammerite, I have never been impressed with it, it can chip, like spreading tar and never seems to adhere well.

A good tractor paint or the Aldi metal care paint... I have started using that and its great stuff for a fraction of the cost of Hammerite

 

[droopsnoot]

I've also been using diamond burrs to reduce some of my welds, will go into electric drill, mini-drill (Dremel-style) or air-operated die grinder. I've used them in places where the angle grinder and flap disc won't fit, they work pretty well but if you can, you want something flatter for final finish.