I agree with @Exuptoy; I switched to a power file with 40 grit belts for sheet metal work.
I also agree with @Exuptoy
Flap wheels are great for removing stock and leave a nice smooth finish which is their greatest strength.
However this can become a weakness when you only have 0.8mm of stock to play with it's very easy to remove too much and not even know it.
It is also very easy to overheat the metal and cause more distortion than you had from your careful slow, tack here, cool, tack there welding process.
If you use a grinding disc you can see the scars appearing in the parent metal before you go too far.
A quick run with a flap disc is then all that’s required.
The cutting edge of a disc will get into spots that a flap wheel cannot, so sometimes it's horses for courses.
I think it's better to leave a few pits than thin everything down for that invisible repair, but it's hard to leave well alone.
I tend to use a (worn) blue flap disc for the first pass if the welds are very high (if the pigeon needed extra squeezing!)...you can take welds down to 1mm-2mm if you are careful then switch to the power file...but if it's somewhere that won't be seen I generally leave the weld a smidge proud. Obviously if it's on a wheel arch then it needs to be flat with surroundings.
I do like the power file....more control....a lot less noise and to be honest I enjoy the process. I don't like using the grinder for fine work....just annoying to use I think.
Thanks for reminding me how I messed up some of my finest sheet metal welding work.
I havea Braur battery grinder - slightly slower than a main so removes less material in the same time. Lighter and quieter - doesn't "scream" like mains ones do - and it doesn't make so much noise in removing metal as its slower. Nicer touse.
The battery grinders are definitely better for car work...I have the DeWalt ...it's quieter than the mains but it still annoys me.
I use a Makita battery one. The only issue is as soon as the torque light comes on a few times the battery is done. Just purchased a twin quick charger and another spare battery as that so I have 3 batteries and 3 charge points ready to go. That was my only issue.
I was hoping to get a few bits painted over the Christmas break but the weather's been too cold, I did get some epoxy and seam-sealer onto the bonnet repair.
I also scraped off the lacquer and sanded most of the paint off and will wait till the weather warms up a bit before doing any more.
With a halt on the outside I decided to start putting the interior back together.
Started by treating all the box sections with Rustbuster MIL-SPEC Universal Wax.
I had already put the steering column and heater in 18 months ago so loom was next.
I couldn't find any before photos so it was a slow job working out what went where.
For an 80s car there sure is a lot of copper.
Dash next. which includes a lot more wiring.
Then I could get the sound deadening mats installed -which are a pain to store so glad to see the back of them.
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