You get splinters and wood pulled when the hinge is a bit thicker than optimum, or when the face closes on a narrow front opening. It's not a problem for tree removal work, and a thick hinge keeps your tree standing securely while you work. Too thick, and you will work harder wedging to the tipping point. Splinter and wood pull is bad if you are cutting grade or better logs, but since you are not doing that, don't worry about it now. Straight cuts on the front and back of the hinge are not difficult to master. Go here:
http://www.youtube.com/watch?v=_EdOL3mWsZg Using your dogs to anchor the saw will really help you.
A wide face angle on the front will keep some trees glued to the stump all the way to the ground like this cottonwood:
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Others, like this black oak are a bit more brittle, and will break loose every time. The guy with the chainsaw in this photo had the natural ability to punch through on a straight line in one try, and make a perfect hinge every time.
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If you can do that, it's great, but be careful until you have the skill level, or you can blow out your hinge.
View attachment 104568 IF you do this on the heavy side of the tre, you are probably OK, and can support it with a wedge. If you do this on the tensioned side, you have some major regrouping to do.
You did a great job getting those trees on the ground, and you have really bumped up your knowledge level. Keep up the good work!
The attachments don't seem to be working. Go Here to see the three photos:
http://picasaweb.google.com/davidn.23skidoo/StumpPhotosEtc#