4.1 hours, 3.25 gallons, and 20 slabs

[mtngun]

Bob, my camera is an older model with modest resolution, so I don't think it's going to get much better. I don't have the latest and greatest photo equipment like you -- all my spending money has been going to chainsaws.

I do plan to experiment with the cutting angle, perhaps trying 55 or 50 degrees rather than 60.

 

[Timberframed]

Mtngun, I can see where that roll of TP could come in quite handy when rounding a tight bend in the road then faced with a log truck like that! I but puckered the Mokee Dugg Mesa cut in Northern Arizona some years ago.

 

[mtngun]

Are you discussing WoodlandPRO 33RP?
The BOX of 33RP I've got has specs of:
tpca - 60°
tpfa - 10°
spa - 80°
raker depth 0.022"

While at Bailey's and they say 0.025" for depth.

Good catch, Gemniii. I must have been trying to read the box without my glasses on.

I was also using the inverse sine function when I should have been using the inverse tangent, not that it makes a big difference in this instance. Arrgh, it's been 20 years since I used trig.

I just measured a few rakers using calipers, on the virgin 33RP, and came up with 0.020" - 0.021", pretty close to their 0.022" spec. For a 0.255" gullet width, that calculates to 4.7 degrees raker angle.

The calculated angle is sometimes different than the DAF angle, but I'm going to stick with the DAF numbers from now on, just for consistency.

I ground the first one at 60°/10°/75°, based on Bailey's.

You are right, Bailey's does say 75 degree SPA on their website, but how do you achieve a 75 degree side plate angle? My grinder does not an option for 15 degrees vise tilt, only 10 degrees or 0 degrees ?

Put a good CB in the truck. . . You can find out if there are any trucks coming, and where they are -- usually called out by mile marker. Takes the whole butt pucker factor out'a driving on a narrow haul roads.

They do call out the mile markers on CB (I've ridden with them a time or two when my truck broke down or slid off the road and they gave me a lift). But one of the local cowboys advised me to get into the habit of driving under the assumption that I will encounter another vehicle as I go through a blind turn, and I found that as long as I do that, things usually work out -- unless the other vehicle is on your side of the road.

 

[BobL]

Bob, my camera is an older model with modest resolution, so I don't think it's going to get much better. I don't have the latest and greatest photo equipment like you -- all my spending money has been going to chainsaws.

I do plan to experiment with the cutting angle, perhaps trying 55 or 50 degrees rather than 60.

OK, I'll go with the pictures you've posted.

Firstly I assume the photo of the virgin chain has been taken after it has been used and is down to the the 0.287 "/s cuttings speed. If so the real cutting edge that enabled it to cut 0.375 "/s in the first place is gone so the real micro hook cannot be seen anyway.

In this picture I have copied the side plate profile of a cutter from the virgin chain and placed it on top of the cutter ground by you.

It's blurry but there is enough there to see the virgin chain side plate profile is circular where as your grind is more of a rounded v shape. When a circular profile is present this means the factory has used a grinder with a larger rounded ended wheel so that the cutting edge is not flat like a basic chisel or plane but one that has a hollow ground giving it a significantly shallower side plate angle than is possible with a conventional grinder.

Here's a comparison of new (ie factory ground) standard Carlton/GB A2 chain (bottom) with my hand sharpening on the same chain (top).

The other major difference between the two chains is the top plate angle is much lower on my chain because I have it set for <10º for milling.

That aside I reckon the side plate profile of your virgin A3 looks more rounded like my file sharpened A2, than either the factory A2 or your grind. The factory A2 also has more of a rounded V like your grind.

The somewhat messy looking factory grind on the A2 also highlights the variability of Carlton factory ground chain. Normally it's OK but in this case it looks to me like the grinding stone was not correctly dressed to shape and the sharpening machine took two bites with the set up was not stable so the cutter side plate has a bump in it - unfortunately it was the last lone cutter in the end of a used roll so I cannot confirm if it was a problem on the other cutters on the roll.

The following is incorrect see followup post.
I know my cutter looks like it has a whopping hook on it but it is less than the recommended for this chain. While I can hand sharpen with just a file, to minutely control hook I use the recommended 13/64" file on a 5/32" file guide which gives me slightly less hook that using it on the recommended 13/64 guide. If I use the 13/64 guide it cuts real fast but for only for the first a half of the a cut and then is starts to slow down and I have to push at the end of a big slab. If I want a really fast spot cutting speed, a 13/64 file on a 7/32 guide will do it. BTW this might work for you guys in softer wood.

Also look at how much I clean out my gullet. This improves chip flow and is really worth doing.

Whether this explains anything you are observing and measuring - I have no idea.

 

[mtngun]

Thanks for the superb close ups, BobL.

Yes, I can see that your hand-filed chain has more "hook". To my eye it is too pointy for a milling chain, and seems unlikely to maintain sharpness for long, but .... I haven't tried it.

The only way I can achieve something similar with a standard grinder is to change the 60 degree cutter angle to something less. Which is what I did tonight. Behold .....

Still not as "hooky" as your filed chain but to my eye it is pretty close to the factory grind.

BTW, after I cropped these two cutters out of the original photo, what was left was only 513 pixels wide. Best my old camera can do indoors using flash. If I have good lighting, I can use the macro function to get a little closer, but I don't have good indoor lighting at the moment.

Regarding cleaning out the gullets, I understand that racers take that pretty seriously. However, since milling chips are so small, I'm skeptical that chip flow is a big issue. The gullet area seems to build up dirt, as if there is nothing moving there. Also, the curved edge of the cutter is still sharp (no glint) at the end of the day, again suggesting that not much is happening in that area. But, I haven't tried cleaning out the gullets, so I'll keep an open mind.

 

[BobL]

Thanks for the superb close ups, BobL.
Yes, I can see that your hand-filed chain has more "hook". To my eye it is too pointy for a milling chain, and seems unlikely to maintain sharpness for long, but .... I haven't tried it.

I agree it looks pointy but that's what I have been using for about 2 years. However, seeing it at such high magnification got me thinking, have I really got the file holder thing the right way around.

After some thinking and measuring, it turns out I was, as we put it here, completely "arse about". What I use is a 13/64" file in a 5/32" file holder and it clearly increases the hook - not decreases it - see below. This may explain why my chain cuts well when I first start a cut and then slows down part way down the slab

Using a vernier caliper on the file guides I measure the 7/32" holder places 22% of the 13/64" file above the cutter tip. Surprisingly the 3/16" holder places 25% of the file above the cutter tip (ie more rather than less) and the 5/32" holder locates only 14% of the file above the cutter tip. The 7/32 and the 5/32 make sense but the 3/16 one does not

Here is what the side plate profiles look like - the 3/16 and 7/32" holders basically generate the same profile and both look much better than the 5/32.

It looks like I have some experimenting to do once these fingers clear up.

 

[mtngun]

It looks like I have some experimenting to do once these fingers clear up.

Experiments in filing? Bet that breaks your heart, eh ?

Yes, the high magnification really helps these old eyes.

I attempted to photoshop your cutter angle, but it was a continuous curve, not a straight line, making it tough to nail down. The very tip of the "claw" looks to be less than 60 degrees, in the "13/64 in 5/32" pic.

 

[mtngun]

Tried out one of the 55 degree chains this morning.

Chain #1, 55/10/10 & 5.3 deg raker, freshly sharpened, 19.5" wide cut, 0.252 inch/sec.

The speed was certainly nothing to brag about, not as good as virgin 33RP.

However, when you convert a chain to different angles, you have to grind quite a bit off to clean up the tooth and get it 100% converted to the new angle. I'm not positive that I ground enough to do that -- some of the teeth looked only partially sharpened -- so I'll give the 55 degree grind another resharpening before I draw any conclusions.

In other news, the Oly was idling poorly, and eventually refused to restart, so I had to call it a day. It's also lost noticeable compression due to sawdust leaking past the air filter, which has been a problem all along. I think I have enough wood to finish the woodshed roof (barely) so milling will be a low priority from now on, and I dunno when I'll get back to the woods.

Hopefully I'll get my Stihls running this winter and then will be using lo-pro and 325 chain, but presumably the same sharpening issues will apply to those chains, too.

 

[DaltonPaull]

Mtngun, thanks for continuing to provide so much good info on chains. I'm glad to hear you have enough wood cut to get your roof on before your saw conked out.

Here is what my chain looks like when sharpened on the grinder according to Maloffs book (0 deg top plate, 50 deg cutter angle. For what it's worth this chain really seams to fly at least when it's fresh.

I didn't realize the raker angle mattered so I'll have to read up on that. I'll try to find something to time the cuts with to provide more data. Tomorrow I'll be cutting green Big Leaf Maple (cuts fast) and dry'ish Oregon White Oak (dulls the chain.)

 

[DaltonPaull]

I tried out the above chain today - here are the results. By the way it's 404 pitch oregon ripping chain on 075 with a 41" bar. I forgot to bring the feeder for the manual oiler today so that might have been slowing me down a little. The maple really seamed to cut fast but I guess it's on par with mtngun's speeds.

First cut - 20" maple @ .32"/sec = 6.4 sq inch/sec
Second cut - 20" maple @ .27"/sec = 5.33sq inch/sec
Fifth cut - 22" dry oak @ .13"/sec = 2.9sq inch/sec
Six cut(after file touch up) - 22" dry oak @ .15"/sec = 3.3sq inch/sec

 

[BobL]

I tried out the above chain today - here are the results. By the way it's 404 pitch oregon ripping chain on 075 with a 41" bar. I forgot to bring the feeder for the manual oiler today so that might have been slowing me down a little. The maple really seamed to cut fast but I guess it's on par with mtngun's speeds.

First cut - 20" maple @ .32"/sec = 6.4 sq inch/sec
Second cut - 20" maple @ .27"/sec = 5.33sq inch/sec
Fifth cut - 22" dry oak @ .13"/sec = 2.9sq inch/sec
Six cut(after file touch up) - 22" dry oak @ .15"/sec = 3.3sq inch/sec

How long are these cuts and how long a distance/time do you measure to get a speed?

 

[DaltonPaull]

The cuts were about 6' long in the maple and 8.5' in the oak. The maple ended in a crotch that widened out to about 32" and slowed me down a little. I was trying to use the same method as mtngun so I timed the runs over a 24" span, expect for the last cut when I only did 18" by mistake.

First cut - 20" maple @ .32"/sec = 6.4 sq inch/sec (24" in 1:15)
Second cut - 20" maple @ .27"/sec = 5.33sq inch/sec (24" in 1:30)
Fifth cut - 22" dry oak @ .13"/sec = 2.9sq inch/sec (24" in 3:00)
Six cut(after file touch up) - 22" dry oak @ .15"/sec = 3.3sq inch/sec (24" in 2:00)

I rounded by a few seconds, but all the cuts came out remarkably close to even numbers.

 

[mtngun]

First cut - 20" maple @ .32"/sec = 6.4 sq inch/sec
Second cut - 20" maple @ .27"/sec = 5.33sq inch/sec
Fifth cut - 22" dry oak @ .13"/sec = 2.9sq inch/sec
Six cut(after file touch up) - 22" dry oak @ .15"/sec = 3.3sq inch/sec

Wow, the speed difference between the two woods is dramatic.

 

[flipance]

I would be interested to know why you use the guide rail after your first cut? Why not just use the Granburgh on the cut log? Thanks

 

[BobL]

I would be interested to know why you use the guide rail after your first cut? Why not just use the Granburgh on the cut log? Thanks

I also usually use log guide rail for every cut.

The benefits for me are:
- the log rails over hang the log at each end so starting and finishing the cut is much easier.
- I start the saw and let it cool off with the mill on the rails, this mean I do not have to carrying a running saw.
- the rails are smoother than a cut surface so there's no transfer of smaller dips and bumps into the cut below.
- the log rails can be adjusted for any twist or dip that might have been present in the previous cut.

 

[mtngun]

I would be interested to know why you use the guide rail after your first cut? Why not just use the Granburgh on the cut log? Thanks

What BobL said.

There is no disadvantage to using the guide rail. No set up on the subsequent cuts, just set it on the log, one screw at each end, and you're ready to go.

 

[gemniii]

What BobL said.

There is no disadvantage to using the guide rail. No set up on the subsequent cuts, just set it on the log, one screw at each end, and you're ready to go.

I've just been setting my unistrut on top and being careful it doesn't slide. No screwing in.

 

[DRB]

More speed info

Husy 365 special totally stock 65cc saw with 28" bar.
Frozen Doug fir cant

First cut - 11" doug fir @ .65"/sec = 7.15 sq inch/sec (12" in 18.5 seconds)
Second cut - 11" doug fir @ .92"/sec = 10.12 sq inch/sec (12" in 13 seconds)

I thought that these number were pretty good for a 65cc saw. I think it may have gotten a little faster as the chain became less grabby I kind of had to hold it back a little at the start. I don't think my 088 would have been much faster. The 365 is much more user friendly and better on fuel with the small stuff.

My data collection kind of when to the side as my hands got cold.

I would like to try 325 on this saw. Finding a thin kerf 24" bar and a 8 pin 325 standard mount sprocket looks to be a challenge. They have 9 pin but I don't think a 65cc saw will pull it. I would like to try Woodland Pro 20NK Chain.

 

[mtngun]

Husy 365 special totally stock 65cc saw with 28" bar.
Frozen Doug fir cant

First cut - 11" doug fir @ .65"/sec = 7.15 sq inch/sec (12" in 18.5 seconds)
Second cut - 11" doug fir @ .92"/sec = 10.12 sq inch/sec (12" in 13 seconds)

That is pretty good for a 65cc saw and 3/8 chain.

 

[Ted J]

Snap a chalk line and cut it freehand with a worm drive Skil saw and 18 tooth ripping blade. The cut is not perfectly straight but good enough for framing purposes.

A aluminum straight edge to guide the Skil saw would be handy, but Santa hasn't brought one yet.

The board often bows as it is cut, anyway, due to internal stresses. I'll often edge an inch oversize, knowing that the board will immediately warp, then snap another chalk line and edge it again to final size. Twice the work, but that's what you gotta do to get straight boards. Maybe I'll post some edging pics later.

Ripping is hard on Skil saws (who would have thunk ?) so you need a good one. The worm drive saws have some gear reduction and they are generally a little heavier duty than the direct drive saws.

Unless I'm missing something...
What do you need an aluminum straight edge for to rip the edge of the slabs? Why not use the unistrut rails as your straight edge to guide the circular saw....?

Ted

By the way, Nice pile of boards for a good day of milling!!!