Circular blade heating up.

[01frick]

Have an old 01 frick that I am trying to start up. The blade I think is around 54". The blade speed s around 500 rpm's is pulled by a 1932 caterpiller d8800 flat belt drive. I believe the carrage and arber are true. The blade is also old with insertable teeth that are sharp. The blade heats up in the middle of the blade within a few feet of cutting the first board. Could this be from a blade that needs hammering or something other? Please help  

[Sawnrite]

Is the blade heating up around the collar or out towards the teeth?
How much set or side clearance do the inserts have?
What are you cutting, hardwood or softwood?

[Tom]

Is this a first, two members using their first post to ask and help?   I love it.

We have some more circle mill guys on here that will be jumping in too, I'll bet.  You fellows are beginning to develop quite a club. 

Welcome to the ForestryForum, both of you.

[01frick]

Today I was trying to cut some oak hardwood and it started heating quickley around the collar within the first two feet. The blade has done the same with pine just a little longer to heat up. 

[01frick]

I have not checked the side clearence. Yes I am new at this, at one time everyone is new at something but I have many years of hard knocks.

[Sawnrite]

The shaft isn't running true. The blade will have a slight wobble or flutter, use a dial gauge to confirm. Set the dial gauge on the bench just in from the gullet. Slowly rotate the blade by hand and you may find a slight wobble.
When the teeth start to cut they pull true but the wobble in the blade is coming from the shaft and so continues to wobble slapping against the side of the cut which is where the heat is comming from.
The shaft may be bent, bearings stuffed or the inner collar may need refacing.
N/B The shaft should only have two bearings not three.

[Ron Wenrich]

Heat can come from a great deal of areas.  A sprung arbor is one of them.

I'm assuming that this is a new installation of an old mill.  The first thing to do is to change teeth.  Put in brand new teeth so you can eliminate poor sharpening as a problem.  Teeth may be sharp, but if they aren't quite straight, your saw will lead out, which will open your saw and heat it.  If the teeth are sharpened to too thick of an angle, they'll heat up (learned that on the hard way).  If they aren't wide enough, that will heat up your saw.

Have you checked your lead?  Just because your lead is a certain distance doesn't mean that you have enough lead.  You have to put enough in so that it will run true.  I had one hand mill that I needed 3/8" lead to run the saw.  Do you know how to check lead?

Is your track straight?  If your track is not straight, especially at the saw, you'll have problems.  It also must be level while the log is in the saw.  If you're moving the log out of a perpendicular plane, you'll be pushing your log into the saw.  That will cause instant heat.

Hows your saw guides?  Saw guides should be set so that you can see light between the saw and the guide while the saw is running.  I always set my guides on a running saw.  Not for the faint of heart, and must be done very carefully.  You can see what you need on a running saw, then shut it down, adjust, restart and reinspect.  Probably a safer method.  You shouldn't be pushing your saw with your guides. 

How tight did you make your collars?  I know of guys who put the saw nut on with a sledge hammer.  That's too tight and that will smash your collars.  I put mine on by kicking on the saw wrench.  Its worked for 25 years.  Old collars may have to be turned to true them up.

Your saw may need to be hammered.  You have to be running at the speed it was hammered, or you'll have problems.  500 rpms sounds a little slow to me.  Most of those mills run about 560 rpm.  I have seen some run much slower, but the most of them ran in the 560 range. 

How are your shanks?  If they are thin, that will allow sawdust to spill out and slide down between your saw and your log.  That means heat.  If you're feeding too slow, then that will make your dust even finer and spill even faster.  If your shanks are wide enough, you can file them and give you more width on the top of the gullet.

The first is to go with the new teeth.  That is usually the root of most problems.

[01frick]

Thanks, Ron I will change the teeth. I beleve the arbor is true. I don't know what speed the blade is hammered at. I will try it at 560 rpms. Is it correct that the lead is adjusted to the outside of the front of the blade(side nearest the carrage) I have paced a straight line on the track, carrage and blade and all appear to be straight except for the lead of the blade. Thank you guys for sharing your knowledge.

[beenthere]

01
Do you have the Circular Sawmills and Efficient Operation handbook by Lunstrum?

http://www.fpl.fs.fed.us/documnts/misc/circsaw.pdf

If not, you may find the answers in there that will give you some good help. 

[DanG]

Welcome to the Forum, 01frick and Sawnrite!  Keep the questions and answers coming, as we all learn from them.  That's what this place is really all about, but don't ignore the fun threads, either.  I don't care how much you know or don't know about one subject, you can be learning or teaching on another.

[Ron Wenrich]

To set your lead, take a tooth on the saw and mark it.  Measure the distance from the saw tooth to a headblock.   You do the first measurement up at the saw guide.  Make sure the guides aren't pushing the saw.

Then, rotate your saw 180°.  Move your carriage to that point.  It should be at your board splitter.  Measure from the same tooth to the same spot on the same headblock.  That will be your lead.

The 1st measurement should be less than the 2nd one.  Your saw should be pointed toward your carriage.  Otherwise, you'll be running your log into your saw.  My current lead is 1/16" or less.

When you saw, your saw should not deflect in or out.  It should saw straight.  There are lots of reasons that it could deflect, but, we can cover that later.   

[Captain]

Any thread that gets Ron going on circle mill stuff is a great one in my book 

[01frick]

Thanks for the information guys. I plan to work on it this weekend. As you can tell this is an antique operation I a trying setup. I enjoy working with this old stuff. I will let you know as things proceed.   

[Frickman]

I'm late to the party, but there is one more thing you can check. Put a straight edge across the log side of the saw. If the saw isn't flat, but dished to the board side, it needs taken off and hammered. That is if your collars are OK. What happens is that the log rubs the center of the saw, heating it up, and dishing it more. I was at a little hand mill one time where the saw was dished 3/8" toward the board side. I told the onwer to change saws. Problem solved.