hitting a "wall" with my scraping

[baileyrash]

I'm a DIYer painting my wood-siding house this summer (I'm a teacher).  My 1900 house was suffering from bad peeling, flaking, etc.  Last guy painted latex Duration on bare wood. Bad deal.

For most of the siding, the bottom half of the clapboard is ready to paint after powerwashing, while the top half has a bunch of bumps and ridges of multiple layers (4-5) of old paint.  Makes for a tough scraping job, but very doable.

However, on the north side of my house, these multiple layers (again probably at least 4 layers) cover most of the clapboard in large sections (with some alligatoring going on too).  I find this stuff almost impossible to scrape, because it seems to be adhering very well and also because it is flat and smooth.  Also doesn't help that these layers occur in large patches rather than just bumps here and there.  REALLY hard for my trusty carbide scraper to really do anything with it.

My question is, what to do?  If it's adhering well, do I just feather the edges, use a high adhesion primer, and hope for the best?

My guts says this stuff should come off.  But how?  Heat gun and scraper will take an eternity.  Any stripping products recommended?

Any experienced advice is greatly appreciated. 

Galen

[chrisn]

Sand off the high points and apply

http://www.ximbonder.com/upload/pdfs/Peel%20Bond%20SS%20LO7.pdf

[BrushJockey]

Peel bond to the rescue!   The heavier, the better. I have only brushed the stuff, which will be a lighter coat, but have put 2 on bad areas.  Spraying you can really build it up I have heard.

[George]

Galen, My apartment house was built in 1857 and I have painted it over the last few years. I have exactly the same problem with old paint thickness etc. I just scraped what I could then used SW oil primer, wait at least 24-48 hours and topcoat with Duration. My house is white BTW. It looks clean and has held strong (some sections for 3 years now).

I think Duration alone over bare wood really requires 2 coats no matter what SW says. In any case you cant beat SW oil primer under it, in my estimation.

As far as the old alligatoring well if its holding very tight as those old paints do then accept it and make the house look neat. Don't kill yourself with heat guns and all that IMHO. The only real alternative is to replace certain individual clapboards if they are really bad.

My house looks neat and super clean. The Duration white satin finish is very bright.