Why has no one ever mentioned Pferd grinding wheels? Options

[mbseto]

I've been grinding welds with the aluminum oxide wheels I get in a bulk pack from HF and always dread doing it. It's slow and it's a drudgery. A buddy showed me one of these wheels and it is amazing by comparison. Knocks the welds down extremely fast and runs cool - no discoloration in the metal. Is anyone else using these?

[Front yard mechanic]

Interesting seems you get what you pay for ! I found 10 for 54.00 claim they run cooler last longer and leave smoother grinds (IMG:style_emoticons/default/welder.gif)

[tygaboy]

The biggest difference I've found is moving to high quality abrasives. 3M Cubitron made all the difference over the HF-level stuff.
And I've used those wheels but found they didn't offer me the level of control I wanted.

I follow this process:
- 3 inch air angle grinder w/ Roloc backer pad
- 3M Cubitron abrasives
- Start w/36 grit, use a steep angle and cut only weld material. Go SLOWLY. I used a "long-ish blip, blip" to keep accurate control over the cutting. Once "close" to the parent material:
- Switch to 80 grit. Shallower angle, same go SLOW approach.
- Once the edge of the weld starts to show a blend with the parent material:
- Switch to 80 grit on a DA to do final blending.

The 3M stuff cuts so quickly, I have yet to experience heat-related distortion.
Pics of a recent repair using the above approach. Hope this helps.

Also, a while back @McMark posted a vid of his technique when doing sheet metal repair. Maybe he'll point us at it...

[McMark]

I think this is the video you're talking about:


https://www.youtube.com/watch?v=z5YEjjqgF_k

[tygaboy]

(IMG:style_emoticons/default/agree.gif)
That's the one. A GREAT tutorial!
Thanks, Teach! (IMG:style_emoticons/default/aktion035.gif)

[bbrock]

Thanks for the tip! I stopped buying any sanding/grinding supplies from HF a long time ago because the quality is (IMG:style_emoticons/default/stromberg.gif), but didn't know about those Pferd wheels. I've used mostly DeWalt because they are available locally. They aren't anything special but way better than the HF wheels at least.

+1 on 3M Cubitron. Money well spent except for their 36g 3/8" sanding belts. I may have gotten a bad batch but totally worthless whereas the 80g belts are magic.

[Andyrew]

In our production shop we use Zirconia resin fiber disks. Cheap and replaceable.

A small disk lasts about 2 days and a big disk about a week.

We use a 36 grit on a 7" disk to knock down a 2" weld and then a 50grit on a 4.5" disk to give it the final finish before an 80grit DA.

I find that this is the best and fastest way to grind down a weld with minimum heat absorption to the panel.




For my house I have a cutoff wheel and then a 60grit flap disk which I should change to a 36 grit.


I find the flap disks to be the most universal for grinding/finishing as they are very forgiving and great for when im one handed upside down or whatnot. I typically go through one a year.

[preach]

Another 1 for Cubitron. (IMG:style_emoticons/default/smile.gif)

[mb911]

Cubitron is very very nice wheel.. We use 1000s of wheels at work 3m is the gold standard.. It also has a really cool history as to how they discovered it.