It should cut clean. Are you using a blade with relatively fine teeth, or something more aggressive? What is the condition of your saw blade (sharp and new, or old, rusty, and gummed up with resin from old cuts)? Is the saw in decent shape, with no wobble?

One more thing...are you supporting the cut with a piece of scrap?

Thank you, kudzu9,

The saw and blade are brand new, the Ridgid 10" CMS with laser, and from what I've done so far, it cuts REAL wood quite well with the 40-tooth OEM carbide-tipped blade that came with it. But not so this plastic stuff.

I was thinking the same, maybe spring for a better blade with finer teeth to finish this project. Would 60-teeth be enough? Any suggestions? I'm kind of wishing that I stuck with the old hand miter box which worked fine last year for the other half of my basement trim using the exact same type of pre-finished moulding. Don't want too spend too much more to finish this job.

I will try using a backer piece of wood next before buying another blade and see what happens with various cuts.

Thanks. I'll let you know how it goes.

I think you need finer than 60 tooth. Something like a plywood blade. You don't need an expensive or carbide blade for this one job. Here's a link to one.

Here is a link that might be useful: Plywood/plastic blade

Thanks, furnone, didn't see anything "finer" than 60-teeth at the few stores I visited. Cheapest was $25 bucks. The type of blade you showed at that price is definately worth trying next, along with a backer piece when cutting.

First of all, score the cut with a razorblade knife. Then put masking tape on the good side or try puting masking tape over the whole line and cutting through the masking tape. You can also try it without scoring the line. Try the simplist way first which would be just cutting through the masking tape. Let me know how it works out for you.

That sounds good, can try taping too before a new blade. Thanks russmahogany, I'll update later to let everyone know how it goes. Much appreciated.

Try a Freud 80 tooth cut off blade.
You are using a very coarse blade for finish work, and it sounds like a combination blade to boot.

Good saw blades are not cheap, and carbide is much vetter than plain steel for fine work.
A steel blade must have set to the teeth to produce clearance, while the carbide teeth are made wider than the plate thickness.

Second the Freud 80 tooth blade recommendation---that is what I use---on my 12" DeWalt CMS. And on my Rigid table saw. And on my Porter Cable jobsite table saw. Mine are labeled 'Freud Fine Finishing Blade'

Make the actual cut more slowly than when cutting real wood. The 80 tooth blade can start melting the plastic if used too fast.

Hi,
look into an 80+ tooth blade with a low hook angle. These are preferred by picture framers who work exclusively with prefinished stuff, the finishes of which can be quite delicate. The low (in some cases negative) hook angle prevents tearout of the surface, but makes for a very slow cut.
I don't know about a plywood blade, unless they now make them w/carbide teeth.
Casey

Hi again folks,

I found a cheapie blade, non-carbide, 200-teeth for $10 and see now what is happening. The moulding is actually melting with it. I suspected that was also the case with the good, carbide-tipped 40-tooth blade as well, but it wasn't as evident every time. I will keep looking for a carbide blade with about 80-120 teeth with the low hook angle as suggested. Hopefully, the next time you hear from me it will be with good news about cutting this stuff in a way other than using the old hand saw miter box.

Cutting plastic requires a fine balance between number of teeth and feed rate.
80 teeth and a moderatley fast feed rate should be smooth enough for a clean cut and fast enough to prevent melting.

I'll butt out, but before I do, How about a miter jig and a handsaw?

I still use my Nobex for a lot of work.