62" bar for the first go... any tips?

[andy]

I have a big curly western maple to mill up (maxes about 50" of cut width"). Hoping to get 4 useable 3" planks plus a couple thick slabs so... only 5)8' lengthwise passes total.
I expect this may be the only time I'll need a bar this length.

Most of what I mill is under 36" and will be after this log.
I chose a inexpensive 62" bar from Forester for the job.
Just received it and I'm getting some time next weekend to mill.. (hopefully it's cloudy)
I have 60" rails and an extra cross brace coming from Granberg to extend my 36" mill to 56" capability (or so).

Any tips for me from you all?
I have the log on a pretty nice incline so feeding should be easy.
Oiler for tip will be in play.
The PH is a 3120xp tuned modestly at 12k.
Chain is 3/8 .063. Full comp (new).

What rim sprocket would you suggest?
I usually run .404-7 on this saw. I have 3/8-7 and 3/8-8 on hand... should I go down to 3/8-6 with the longer bar ?
I've never actually experienced much chain "stretch".
With that in mind, ....should I buck a few rounds to break in this chain before clamping it into the mill?
Any thoughts on this or other things?
Thanks

 

[BobL]

Chain size and rim pin # is dependent on how aggressively chain cutters and rakers are setup.
Problem is you can't predetermine things without some experimentation.
I suggest starting with a 7 pin, 7º raker angle and a 50º TPCA and unless you already have milling chain don't worry about the TPFA and just make that angle smaller each time you tough up..
You will get significant chains stretch and adjust chain tension on a 3120 when in the cut is a right royal PITA.
Bucking a few big rounds is good idea. Tip, start off quite tight, ie tighter the normal.
You might need an anti bar sag device - do a search for that for ideas.
Good luck.

 

[ML12]

I'll second Bobs comment on chain tension, brand new Oregon .404 (on a 60" bar) stretched substantially about 6" into the log. Had to back it out and re-tension. Make it really tight.

 

[andy]

Ok thanks guys.

I've run as my longest to date... .404 36" 104dl and have yet to experience much stretch.

I guess 3/8" 62" and 185 DL may be a different story.
I'll get it snug and go noodle for half a tank tightening as I go.
Not really my idea of fun but neither is a loose chain mid rip.
Thanks again.

 

[blades]

Take the tension off the chain when you finish running for he day or are letting saw cool off helps reduce streching. On a blade that long really need an oiller at far end nothing fancy just some sort of drip bottle. another little trick is to open up the oil port in the bar and grind a groove to it at the same point as the saw oil port.

 

[brianpoundingnails]

Everything they said. 60" on a sthil 084 in the first pic. 44 on the second pic. I coughed up for a carbide chain and if you keep it wet it will cut through nails and cable
without slowing down. My chains tend to stretch 6-8" , sometimes I will have to remove a link or two(168 links) to keep it tight on the saw. I f you grind one tooth left,
one tooth right, third tooth flat.(alternate top bevel) they will cut much straighter and last longer. When you grind your teeth also grind your depth gauges for a more
aggressive cut

.

 

[andy]

Thought I posted these here previously.... guess maybe it was somewhere else. Anyway... some pics

First task for this extended length set up was to split one leg of a "Picklefork" Hemlock ..... I will likely use for a wrap around fire-pit bench.
I tried to pre-stretch the chain by doing a bunch of cuts in some hard old maple lumps laying around but again got little stretch.
It only loosened a little in the cut of this hemlock.

I only had 8pin rims so I left the rakers at factory which was just at gauge height..... it did not self feed very well.
Since, I've received some 3/8-7 rims and will file these rakers a touch and get a better bite.
I usually have the rakers pretty aggressive with this big saw running a 36" B/C.
First time ripping with the 62".... much to learn. The 3120 Has plenty of "sack" to bite a bit more.

The cut came out great. No complaints.

The offending tree... It's near dead.

Setting up

 

[blades]

nice cut real neat pieces. got a 48" mill and a 42" bar with an 084 for power,.404 chain- haven't had time to play yet.