Removing OEM (White) Seam sealer - best with no damage

[lmar]

So,

I am on my 3rd bug where I have to remove the VW sealer in order to repair or drill out spot welds to remove the heater channels.

The front is no big deal as a combination of wire wheels, oscillating scrapers, and roloc wheels make short, but messy work. Lots of room to work.

The rear, is entirely a different story. The stubby heater tubes protruding at an angle, and tight clearances prevents one from getting into all the nooks and crannies using the same tools.

While drilling out a spot weld with a dull 3/16 drill bit, the bit accidently slipped off the spot weld and dug itself into the adjacent seam sealer.

In frustration, I didn't let go of the drill's trigger, and proceeded to watch the drill bit plow through the sealer until a chunk of the sealer popped off.

The next time, I let the drill bit bottom out and then gently forced the bit sideways. The drill acted like a grinding or router bit and I was able to remove the seam sealer fairly quickly and in surprisingly in large chunks.

Aha.

I dragged the running bit along the seams and pretended it was a carbide grinding bit. The sealer came off fairly quickly.

I observed the following:

1. The low speed of the drill didn't produce stringy melted seam sealer smoke.
2. The dull drill bit would cut into the sealer, but stop when it hit metal, leaving the metal undamaged.
3. I could remove sealer in areas no bigger than the diameter of the drill.
4. The sides of the drill bit won't damage surrounding metal when routing.
5. The long reach of the drill bit is able to get to areas no other tool can.
6. 3/16 drill bit is about right as it allows you to put sideways pressure on it without snapping.
7. Only tool I used to clean out sealer in this area.


I was very surprised how effective it was once I started trying different techniques. As I got more aggressive the sealer came off faster and cleaner.

The factory seam sealed the channel at the bottom of the interior side of heater. As a lark, I proceeded to angle the drill and plunged it into sealer. I wasn't expecting to be able plow the drill into the sealer and move very fast. Too my delight, it zipped along and cut a groove along the length of one side. I repeated procedure on opposite side and a duplicate groove appeared. Was able to grab remaing material and pull it out of the channel.

Pretty pleased how things turned out considering it was accidental.
Will take pictures and post my results.

[Bobs67vwagen]

That sounds like a nice method for removing seam sealer that you have discovered. I would be interested in seeing pictures of the results.

[lmar]

Here is a picture of the area prior to cutting out the metal.

It was clean enough using the method that I could pick up spot welds for drilling.

Here I am using the side to clean paint off off the heater channel.

First pass using the method.

Doing some more cleanup prior to drilling and cutting.

What it looks like now.

[Bobs67vwagen]

Nice tip and nice work, thanks for sharing it.