how do you grind your welds

Rat Rods Rule

Help Support Rat Rods Rule:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

gold03

He lives in an "Altered State"!
Joined
Nov 28, 2009
Messages
1,175
Location
Edmonton, Alberta
I know it sounds like a silly question. I'm trying to improve the finish I get on welded body panels prior to doing my roof chop on the 49.

How do you grind your welds when welding body panels? I am using a small side grinder with a flapper disk, and seem to always get to much taken off near the weld.

When I look at some of the metal finishing guys have done I can't figure out how they manage to get it so smooth and blended in with the steel around the weld.

What tool do you use? Flapper wheel, sanding disk, grinding wheel, magic?[S

gold03
 
Elec grinder then flapper wheel seems to work best for me. Just try not to heat things up too much and cause warpage.

Zipper
 
I use a combination of magic and 120 grit flapper discs on a 4-1/2" electric grinder. The MIG weld is a lot harder than the surrounding metal, so once you start to touch the metal, ya gotta stop.

I did have some warpage on my roof in a few spots. Not across the whole roof, but a few places on the weld seam where it sucked in. To bring those areas back out, I turned off my gas, got underneath and ran the MIG along the weld quick to generate pinpoint heat without adding metal. Probably not the right thing to do, but as many have said, I'm not right. ;)

I did manage to MIG hammer weld a couple spots a little, but you have to be so quick to grab the hammer it's nearly impossible. Maybe with 2 people, but even then it won't come out looking much better than a ground down MIG weld.

Next time I'm just going to try to find an alchemist to do it for me.
 
I like to use a 90* grinder and roll lock disks.Seems to work well and gives you control.

0.jpg


Roll%20Locks%2024%20GRIT%20Disc%202%20inch%20100pc.JPG
 
Thanks for the feed back guys. I knew about the hammer weld technique but when I have tried it it seems to get cold to fast. hammer weld can be done on a cold weld just takes longer I understand.

I like the roll lock idea. smaller disk and grinder as well. The flapper wheel I use seems to leave me with to much of a blind spot. The other thing is the electric grinder is on full bore and can't be throttled like the air grinder.

gold03
 
I use a weld grinding wheel on my die grinder. It is like a 1/4 inch wiz wheel blade. Lots of control and no blind areas. I get it close then use a flap wheel to finish it off. Followed but hammer and dollie work then a DA to get it blended in seamlessly
 
Last edited:
I use a weld griding wheel on my die grinder. It is lime a 1/4 inch wiz wheel blade. Lots of control and no blind areas. I get it close then use a flap wheel to finish it off. Followed but hammer and follies work then a DA to get it blended in seamlessly

Is that on MIG welds CC?
 
I use the 4" grinder and a 60 or 80 flapper wheel.
I also use the rolocs but I find the 4" blends better in my opinion... also takes material away much faster .

I do A **** TON of hammering as well.... like to the point where I cant hold a glass afterwards without my hand shaking after holding the dollie that long...
 
die grinder, and a weld buster disc makes quick work of it.

just like a cut off wheel, but 4 times as thick.....



then a 90degree whizzer with a 36 grit disc.


---

this is the fastest and least laborious way I've came across removing sheet metal welds...
 
if i remember today i will snap a pic of one, the brand i use is falcon. pretty much all they are, are a 1/4-3/8 thick wiz wheel blade. they work great for many things
 
The best way it to start with a flexible hard wheel (Pearl 4560 I think), transition to 40grit flap and perhaps down to a 60 or 80 grit flap. Some situations call for a rubber backed flap sanding disk. Here is the most important tip I can give you.... for example if you were sanding a rounded surface that is horizontal... sand top to bottom (around the curve) by holding the grinder straight in front of you with the wheel flat on the surface. NEVER the opposite way. On flat surfaces... use a rapid circular motion while trying to get the wheel down flat on the surface. Grinding off the edge causes gouging.
Best products to buy.... Pearl Abrasives
 
I save all of my left over/ to small, cut of wheels and use them to nock down the welds on edge. i seam to have good controll and i can pin point a small area more than a flapper disk.
 
I don't post here alot, but figured I would chime in on this.

One thing I have found that works good is old worn out scotchbrite pads. The roll lock style. When I get down to where you can barely make out the weld, I will switch to the worn out scotchbrite. It blends them pretty seamless and takes out the marks from the grity pads.

The really fine ones work great on aluminum.
 

Latest posts

Back
Top