Circle mill blade heating

[whitepine2]

  Hi Dave what's going on any change with the thick and this saw mill,Pic ect.
I have gone over what you have done and like said sometimes ya need to skin the cant. Circle mills are fun uh sometimes mine will cut true and square
other times thick and thin ya gotta talk to them and have a good understanding of what makes them tick just soooo many adjustments one has to be an engineer of sorts took me years like you to set up but all makes you a better trouble shooter in the end.

                Good luck don't give up you'll gether true takes time.

[ddcuning]

Whitepine2, I haven't forgotten the thread, just haven't done much at the mill. Last week was the "Tall Trees and Blue Sky's" event at NCDiesel's and today I am up at 5am headed to get an edger. I did sneak over to the mill one night and fix a couple of small problems. My drag chain had a gear cog at the bottom and the chain kept coming off of it so I replaced it with a roller and built a small guide to guide the chain onto the roller. We also noticed that there was one axle on the carriage that was not in he best contact with the way so we shimmed it 0.025" and now there is no slippage. I will get back on the alignment issue next weekend...hopefully.

Dave C

[DMcCoy]

Deleated, sorry, I see we are on page 11 not 2.  :-[ Glad to hear you found the problem.

[Jeff]

I made a manifold to put water on my blade and bearing. so 3 outlets; bearing, inside and outside of the rear portion of the blade so it would take water into the cut.  I could never cut without water.

There is something fundamentally wrong with your set up if you need to use water to cut. Circle blade technology does not require water. I'm not talking out of not knowing anything about it either. I spent 25 years as a circle mill head sawyer in a commercial mill as well as onsite consultation with numerous local mills to trouble shoot their issues. If you have to use water on a circle head rig to cut, something is very wrong not to mention the resulting mess and corrosion issues of equipment that sets up.

[DMcCoy]

Yes, absolutely, the water is compensation for what I think is heat from the babbit bearings.  I think the bearing starts getting the saw warm and it leads out, compounding the problem.  It's a really old mill not worth the money to me for upgrades given its low use.

[Ron Wenrich]

Or it could be the saw heating up that warms up the bearings.  Do the bearings get hot when you just run the saw without sawing?  If they don't, then you have a saw problem.

I was with a bunch of mill guys at a mill in Canada that ran water on his blade.  We laughed.  Only time I ever saw it. 

[Jeff]

Problem bearings will definitely transmit heat to a saw arbor and collar and then into the blade. I'd say much more often than vice-versa as Ron mentioned, but that is also entirely possible. Something I mentioned looking at as a possibility early on in this topic. Babbit is available many places. Almost every old engine show you can find it. have you considered re-pouring?

[DMcCoy]

It's a Belsaw M -14 (est. 1950's).  I haven't used the mill for 14 years +/- and I'm building a bandmill because of the waste in sawdust.  I think if I were to spend the money to fix it up I would move the saw shaft from under the track to the outside and fit it with good roller bearings.  I do really like the circle saw marks on cedar board and batten siding there is nothing quite like it. So I need to make a board scratch-er ;D   

[GeneWengert-WoodDoc]

How much play do you have in the log moving mechanism?  What sometimes happens is that the mover moves a little bit and then has to stop, so the "backlash" results is one or more knee not moving perfectly.  With two inches, you have a longer move and so the back lash is the same on all knees.  Also, when you set 1", maybe you set just a hair too much, so you had to back it up an 1/8" and one knee has no backlash, so it backed up 1/8" as desired, but the other did not move as the reverse action took up the backlash sloppiness instead of moving.  If this is not clear, maybe someone else can explain it more clearly.

Try this.  When ready to saw a 1" piece, reverse the mover so that the log is now 2" away, and then measure the distance of each knee from the saw.  Then make a 2" set and see what distances you get.  We are trying to see if going from reverse to forward has the same movement for each knee.  (In this test, the sawblade is not moving.

You can check the mill overall without a log on the carriage and make a bunch of sets and see how far the carriage knees moved in total.  Then put a log on and make the same sets from the same starting point and see if you get the same amount of movement.  The weight of the log can also affect the movement of each knee.  Note that you will want to measure each knee movement separately.

Finally, back the log on the carriage to the original and, if you can, make the same sets, but also make a reverse set between each positive set...this will check if something is slipping, if there is the same movement with each set in each knee, or there is a lot of backlash.

[bandmiller2]

DMcCoy, the later Belsaws used a common flange type bearing, mayby one of the Belsawyers could get the number off theirs. Mayby check your lead too. Frank C.

[ddcuning]

Well it has been a while since I worked on issues with the mill. After machining the  fast collar and replacing the outer collar, I was just so happy it was sawing at all that I didn't care that it was sawing a slight wedge. So tonight I went through the alignment again and found some issues. First we had the blade hammered earlier this month and got it back on the mill. Tonight we aligned the first knee to the blade and after running the carriage back and forth a few times the dimension changed by 3/16 of an inch. We invetigated and found the end of the track at the log deck was misaligned such that where the two tracks met, there was a 1/8" offset. This caused the carriage to "bump" every time it went over and was throwing off alignment of the knees since the carriage was over the offset track during us aligning the knees. We fixed this and still had the same problem. We noticed that with the knees retracted away from the saw, the wheels on the saw side were ridding up off of the grooved portion of the track. Not sure what is causing that. I can bolt some train track sections to the carriage on the saw side to offset the weight of the knees when they are retracted. Not sure what else to do. Advanced the knees to within 5" of the saw and the wheels stayed on the guide of the track. Still had the same trouble so we tightened the loose cable that drives the carriage and noticed that when I advanced the carriage, a frayed portion of the cable at the front of the carriage was catching in the front cable sheave. Cut the frayed portion off and now with everything else done, the carriage runs smooth. Realigned the knees to the saw, ran the carriage back and forth and the dimension stayed the same. A log on there will keep the wheels in line on the track so I will saw some in the morning and see how it goes. Still not sure why the saw side wheels are lifting off of the track.

Dave C

[backwoods sawyer]

Almost sounds like a chair sitting on uneven ground.
Where you have recently levaled the rails it could be a wheel bearing on the carrige allowing it to rock.

[ddcuning]

Not a good sawing day. Back to where we were with heat in the eye and blade flopping around like a fish out of water. Some of the cuts you would have thought done with a dado blade they were so wide.

We found that the cover I made for the shaft was rubbing on the eye of the saw blade so I think that is where my heat came from. The blade was flopping around at an idle from the start and only got worst with speed. I just had it hammered and it sawed much better before I got it hammered. I am going to recheck a few things but with it flopping at idle and it didn't do that before, I suspect it didn't get hammered correctly. I have two other blades that were hammered with it to try. It cut fast and smooth, just wide from the wobble.

Dave C

[Ron Wenrich]

How's your sawguide?  With that type of flopping, your saw guide must have worn down quite a bit.  Sometimes when you get a blade heated, they need to be rehammered.  I've always been able to get them to work.

If you're getting carriage movement, that will heat a blade up, as well.

[ddcuning]

Ron, it was flopping bad before it got heated. Once it heated it moved over to the inner guide pin then heated in the rim from the guide pin.

Dave C

[lyle niemi]

Ron, it was flopping bad before it got heated. Once it heated it moved over to the inner guide pin then heated in the rim from the guide pin.

Dave C

sorry to hear about yer troubles, better come up and see my old mill

[ddcuning]

Apparently when I machined the fast collar I didn't get the taper good enough. I papered the collar this weekend and the blade issues got much better. Good enough to saw but not 100% stable. So, I contacted Frick via email and I am going to order a replacement shaft with new collars. The nice thing is, this will solve my issues with the collars and it will upgrade me from the 4-1/2" collars to the 6" collars which will be more stable. I am also ordering the shaft bearings and replacing all of them. No sense in taking all of that apart and not replacing the bearings.

Dave C

[Ron Wenrich]

6" collars will make a difference.  Are you going to raise the track?  Or did you have enough clearance at the collar to accommodate a larger collar?

[bandmiller2]

Dave, its time for a fresh set of eyes to look at your mill. Possibly your hammersmith  knows of such a person in your area that can troubleshoot mills. I feel bad for you Dave you cut no corners but theirs something that isn't just right. Almost sounds like a problem with the track or carriage wheels. I would put a good level on the knees near the end and slowly push the carriage by the saw by hand checking for deviation especially near the saw. Carriage wheel end play is worth checking, by trying to move the carriage in and out with a bar. Hang in there mate. Frank C.

[ddcuning]

Ron, that is something I am going to have to address. I have not taken any measurements yet but will work through that issue. I had considered going to pillow block bearings and removing the existing bearings anyway. With new bearings, I could shim there if I needed to.

Frank, I am not saying that I still don't have some carriage issues to work out but when all three fresh hammered blades flop at idle and at speed without moving the carriage, then I paper the collar and the blade straightens, I am not sure what else it can be but the collars or shaft. After papering the fast collar, the blade was straight at idle and at dead on 600 rpm had a little wobble which could be a slightly bent shaft. No telling what this mill has been through in its life, a new shaft and bearings can't hurt and I get the more stable 6" collars in the process. I don't mind spending the money if it eliminates that variable and besides, the wife said buy the shaft and bearings so that means I am just being a good husband by listening to her!

Dave C

[Ron Wenrich]

Wouldn't shimming the bearings raise the shaft?  That's not what you want.  You could shim the trucks on the carriage.  I'm sure you'll figure it out.

[ddcuning]

Ron, I mean the bearings on the carriage which would raise the carriage. We are saying the same thing just using different terms. I didn't mean shimming the bearing stands on the shaft.

Dave C

[ddcuning]

New mandrel, collars and bearings are on order from Frick Co. and supposed to ship either tomorrow or Wednesday. If they come in by Friday afternoon, I will be changing the mandrel this weekend and then start working on what it will take to raise the carriage for the new 6" collars.

Dave C

[ddcuning]

After a long week of traveling for work, I got home Friday just in time to receive the new shaft, drive sheave and bearings. Went straight to the mill of course and started work.


Prior to starting, this is where we were. I had put the 2-1/2 - 7 blade on but had not sawed with it so we removed it first. Next we took all of the drive and V belts off.


Getting that big sheave out was a challenge but with me and my friend Steve, we were able to lift out the sheave and shaft in one piece to get it on the platform.


Unfortunately, my V belt sheave is the old style that is just fit on with a sleeve between the shaft and sheave. So, we sprayed it good with Kroil and started beating on the end of the shaft with a sledge.


By the time we got down to an inch or so, we had mushroomed the shaft a little. Steve used the grinder to grind off the mushroom and we were then able to use a jack between the drive sheave and the V belt sheave and the V belt sheave came right off.


I was eager to get the old bearings off of the old shaft and get the new shaft on.


The new shaft was fitted with the more stable 6" collar.


Of course as has been true for my luck with this mill, when we took the bearings off, the sleeve that sits between the shaft and bearings was shot. It may be hard to see in the picture but the inner bearing race has been spinning on the sleeve. Grooves large enough to catch your fingernail on are worn into the sleeve. Of course, I did not order these when I bought the new shaft. Got on the phone and got two on order. Problem is, I have a trip scheduled for next weekend so it will be two more weeks before I can assemble the shaft on the mill.  >:( In the mean time, I will get the bearings out and put the new bearings in the housings.

Dave C

[Seaman]

Your killin me ! I would have burned the thing down long ago!

I really hope this works for you, you have been through enough heart-ache already.
Frank