I want to cut a log into about 2" thick cross sections to make serving platters.
Can anyone please tell me what the best way is to get the smoothest/ cleanest cut?
I heard a chain saw, but is there some sort of guide that will help make clean cuts? Is there a better saw to use than a chain saw?
Thank you!
Is there a better saw to use than a chain saw?
Yes most definitely. A chainsaw will do the cutting for sure, but the resulting cut surface will be a bit, ah, rustic. Chainsaws have never been accused of producing particularly smooth/clean cuts :-)
Very related previous Q&A: Crosscutting 18" diameter logs by hand.
This doesn't mean you can't do the cutting using a chainsaw, it'll do the job very efficiently. But you do then need to smooth off the cut surface quite a bit to make it flat and smooth.
You didn't ask about this but further processes are nearly always used to finish off rounds like this.
Sanding
Probably your best bet to flatten and smooth if you can get the chainsaw cut fairly even is with power sanding, maybe with a belt sander to begin with using a coarse grit, then switch to a finer belt. So you might start with 60 grit (possibly a little coarser) then move to 80 or 100.
Then you'd switch to a random-orbit sander to smooth off, e.g. using 100 then 150 then 220 paper, possibly finer depending on the surface quality you're going for*.
Prepare yourself though, even with power sanders this can be quite a bit of work even with softer species — you're working an end-grain surface and end grain is the toughest part of the wood. If you're using a harder species, particularly a hard hardwood, this can be extremely tough going so you need patience and perseverance.
Router
If you have a router flattening rough-sawn rounds is one of the things they can do brilliantly, using a simple homemade jig:
This way you really don't have to worry that much about how rough the chainsaw cut is since the router can easily tackle an unevenness of 1/2" (13mm) or more, as appears was the case in the photo above. Note: you wouldn't take that much off in in one pass, you'd use numerous shallow passes so as not to over-stress the bit, the bearings or the motor.
More on this sort of levelling jig in this previous Answer: Flattening the face of a board without using a jointer.
*This relates to how you want to finish. Finish type (if any) is a factor in how finely you want to sand any surface. If you'll be putting on a full film finish (varnish, lacquer, epoxy) you can get away with some fine scratching because the finish fills these up. If you intend to leave the platters bare, or just give them a light oiling then generally you want to finish to a very high level (240 grit or higher) because surface defects are very easy to see.
I cross-cut some 4-6" diameter limbs into little candle stands varying between 4" to 10" tall using a chain saw. While the results were a bit rustic (to borrow Graphus' term), that was really what we were after, so it worked well.
It was surprisingly easy to get the cut faces to be pretty parallel, and they were really rather smooth considering the tool I was using. Out of more than a dozen made, there were only a couple where I had to do any significant amount of (belt) sanding to get a flat enough bottom surface for the branch to be stable. The rest just needed a bit of sanding on their top surface to ensure enough flat space for the candle to not tip.
Since you're making serving platters, I'm assuming you're going to want a very smooth surface, so you're going to need a fair bit of finishing work no matter what cutting tool you use to make your rounds. I'm also thinking that you're going to need something to hollow out the inside a bit, because an 18" diameter, 2" thick piece of trunk is going to be a very heavy tray long before you put anything on top of it to be served.
Since (I'm guessing) you'll need a lot of finishing work, I think the chainsaw would work quite nicely for you if you already have one (or can easily borrow one). While a band saw would give you a much nicer starting cut, maneuvering such a large log through it would be difficult, at best. Hand sawing might give you a better finish, and it will certainly give you a bigger bicep, but you'll still have to do some sanding.
I would venture to say that after a couple of tries, you'd be able to get some pretty decent 2" rounds with a chainsaw. I was cutting White Aspen, so I used a black Sharpie™ to mark the top to length, then used a Mk I eyeball to gauge the correct angle to make it parallel to the existing cut. If you're cutting a dark wood, use a silver Sharpie™ so you can see your lines. Since you're cutting a larger diameter, maybe make several marks around your wood to better help line up the saw. Also, debark, at least in the cutting zone, since the chainsaw will likely rip the bark off before cutting it, and your marks will disappear. Finally, be sure you're using a freshly sharpened chain - it will make your cutting much, much easier.
