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View Full Version : Fleam & rake for a miter saw



Mike Holbrook
11-21-2013, 10:23 AM
I know what fleam and rake are but what I don't understand is how small cahnges seem to influence how a saw cuts. I am ordering a saw from Ron Bonz for the Stanley 150 miter box I restored. We came up with a 20" long, 4.5" wide. .025" thick plate as being good choices but I am struggling with tooth design. I have a 24" Gramercy Sash saw with the combo teeth which is helping to confuse me. From what I know the Gramercy saws teeth are close to a rip pattern but they seem to XX well too, which I do not quite understand. I suspect that pattern might not work on larger teeth. I started thinking about a combo tooth pattern for the miter saw, thinking a longer tenon saw would be nice too. I am currently thinking that I do not want to compromise the miter saw by trying to ask it to do two jobs.I thought I would ask for opinions from those who have more experience filling various patterns.

I am mounting the 150, which is a small (14" long) miter box, on a bench hook type arrangement so I can use it like a bench hook, keeping it stored on a shelf under the bench. I plan to saw small to medium sizes pieces for door, table and cabinet frames with the saw.

Chris Griggs
11-21-2013, 10:29 AM
Standard xcut. 15 rake, 20 fleam. I think its the standard for a reason. That's what I would go with. Maybe 25 fleam which does make for a slightly smoother xcut, but it will dull faster, so I'd stick with 20 if you don't file your own saws.

Jessica Pierce-LaRose
11-21-2013, 10:48 AM
I've a short mitrebox saw (11pt, 16" toothline, I think) and I had been using it as a tenon saw for a while, filed pure rip. It works, but a mitrebox saw with it's thicker plate is a little less than ideal. The thing that killed me using it was the weight of the darn thing, although mine did have a steel back. It's crosscut again, and I use for dadoes now and then, but I really don't find I like using the thing outside of the box because of the weight. I can't guess as to the weight of your saw in question, but I'd imagine with a slightly thicker plate than standard backsaws, and 20 inches of length, it'd also be a bit heavy and awkward.

My experience with ripping tenons with that saw was that at that size, I wanted coarser teeth, too. In the work I've done, it seems like once I get to a tenon sized large enough where something like a sash saw wouldn't cut it, I move up to either a japanese saw or a panel saw. I've actually done pretty small tenons using my 7pt rip saw (which is maybe 22-24 inches long - I can't remember) because I like to go fast. If it's sharp and straight, it gets the job done with aplomb.

Jim Koepke
11-21-2013, 1:46 PM
I know what fleam and rake are but what I don't understand is how small cahnges seem to influence how a saw cuts.

Most of my initial understanding of this comes from reading sites like vintagesaws.com. The library there has lots of good information.

The points per inch, rake and fleam determine how aggressive (fast cutting) or smooth (slower cutting) a saw's performance will be.

A rip filed saw has a tooth cutting perpendicular to the direction of the saw's movement. A bit of fleam creates more of a shearing cut through the wood.

The rake determines how the tooth's edge is entering the wood. On a rip saw zero rake will be fast, but it is also rough. Starting is much easier with 7-9º or rake.

This is one reason sharpening one's own saws is a good skill to pick up. Buy a lot of cheap saws to play with to find where your own personal preferences may be.

jtk

Jim Matthews
11-21-2013, 6:14 PM
I recently resharpened my Langdon miter box saw (it's a Jennings, around 26" long with 20 TPI).

I can't reliably keep track of which tooth goes which way (for crosscut) with teeth this small, even with good light and a magnifying glass.
I sharpened them all rip cut, with progressively steeper rake as I moved back from the toe of the saw.

It cuts fine, this way - if a little slower than a top flight crosscut saw with teeth this fine.

The steel on this old saw is considerably softer than the modern Spring Steel used in my Bontz saws,
it went quickly. Sharpening Ron's saws takes more time, but they stay sharper, longer.

Casey Gooding
11-21-2013, 8:21 PM
Honestly, you'd be just fine letting Ron decide your tooth configuration. He has the knowledge and the skill to set you up right.

Mike Holbrook
11-24-2013, 12:12 PM
Thanks for all the info. guys. I have been discussing how to sharpen the teeth for this saw with Ron. I just did not want to bug Ron too much. I just got a little lost between two very different saw specs. Ron asked me about the Gramercy Sash saw tooth configuration, as he knew i had one. I mentioned I was surprised at how well a saw, with what I understand to be a largely rip tooth pattern, crosscuts. As a result I think he may be thinking I want a similar pattern on the teeth for my miter saw. I think the pattern Gramercy uses for the teeth on their Sash saw may work because: the teeth are small (13ppi), the plate is thin ( .020) and the teeth are hammer set. Like Jim mentions with the saw he just resharpened 20 TPI, when teeth get smaller various patterns may change in relation to their functionality.

I think Chris "Big Mallet" Griggs mentions what is more of a standard XX pattern, at least for larger teeth. Tooth size is the other question I am toying with. Ron's last post mentions 10ppi with about 6 rake and 5-10 fleam whereas he originally mentioned a 12-14ppi saw with 15 rake and 10-30 fleam. Ron seemed to favor 15 rake and 25 fleam as a good all around performer. I think Ron was trying to accommodate my affection for the Gramercy saw in his last post. I am just thinking I am better off going with something along more classic lines like Ron's original idea say: 20" x 4.5"x .025" plate, sharpened 12-14ppi, 15 rake and 20-25 fleam. As I mentioned at the start this saw will be attempting to be an improved performer vs a shorter backsaw and bench hook. It will saw hardwood frame material for cabinet carcasses and door frames, hardwood for chairs and other furniture.

Ron Bontz
11-24-2013, 7:13 PM
As always I am late to the party. I started to write a response then realized it was rather long. So I posted a general tid bit on my web site under "Ramblings". I did not go in to too much depth on each aspect. I hope to write more as time permits. But I am a lousy writer and don't tend to sit long enough for such things. It would suffice to say there are many ways to skin that cat. It just comes down to what ever works best for you. I don't know how they file the Grammercy saws, but I'll bet Joel will tell you if you ask. Best wishes, Ron

Jim Koepke
11-25-2013, 12:27 AM
So I posted a general tid bit on my web site under "Ramblings".

Thanks Ron, that was an enjoyable read. Some good information to ponder for one considering making or buying a saw.

jtk

Kees Heiden
11-25-2013, 3:00 AM
I love your Ramblings Ron. :)

I have an Ulmia mitersaw (the 352 to be precise). It came with several blades. Most had hardened teeth, 14tpi rip cut with a very agressive negative rake. And they were impossible! I don't know what the German Herr Doctor Oberingenieur was thinking when he designed this teeth configuration. Hard to start, hard in the cut, catching every other stroke and leaving an awfull finish. Nowadays Ulmia promotes a blade with hardened Japanese blades for their mitersaws. They probably forgot about usefull western technologies.

There also was an older unhardened blade. Dull of course. So first I sharpened it with the existing tooth geometry. 14tpi rip, but at least it had a bit of rake in the proper direction. Much better, but still not leaving a nice surface. So I resharpened it in a standard crosscutting geometry. 14 tpi, 15 rake and 25 fleam. Perfect!

A mitresaw is used exclusively for crosscuts. It is very precise. So it would be nice if it leaves such a smooth surface that you can use the endgrain with none or almost none planing. That's what a crosscut tooth patern is ment to do.

Jim Matthews
11-25-2013, 7:12 AM
I get a finer finish crosscutting with traditionally filed teeth - no argument there.

I just go a little slower and "easier" with the saws I have sharpened.

I'm just suggesting that the simpler filing method, with a proper set on smaller teeth will work with less fuss.

Best mitering saw I've ever used was a Nobex, and it was a 12 TPI crosscut.
That thing sang through almost anything on the box.

Hilton Ralphs
11-25-2013, 9:25 AM
A mitresaw is used exclusively for crosscuts. It is very precise. So it would be nice if it leaves such a smooth surface that you can use the endgrain with none or almost none planing. That's what a crosscut tooth patern is ment to do.

I agree with this plus you need to remember that dedicated mitre saw will be a lot heavier than normal so get the teeth filed to give you the smoothest cut possible.

Mike Holbrook
11-25-2013, 10:45 AM
Wow, Ron covered the topic of hybrid cuts and gave us all lots of great info. The Gramercy Sash saw is listed as 13ppi, -5 (negative) rake, 7 fleam. So it sounds like the Gramercy saw is relatively close to Ron's standard rip saw with 5 degrees fleam, or maybe it isn't. 5 degrees does not sound like much, I'm not even sure if I can see a 5 degree change in fleam or rake. I have real doubts concerning my ability to be that precise hand sharpening saws. Although, my eyes do tell me that the Gramercy Sash Saw teeth look a little like hooks. It could be that hammering teeth with some negative rake would increase the visual and actual rake. It is the 5-10 degree differences that I wonder about in terms of end results. As I understand what Ron wrote there are some angles, either side of which, there are diminishing returns. 15 degrees of rake on a XX saw seems to be one of those numbers. Another interesting educational piece of Ron's Ramblings for me was the realization that everything is some sort of compromise. Although I like my Gramercy Sash Saw I think I will ask Ron to file my miter saw in the pattern he finds the best compromise 15 rake, 25 fleam, probably around 12ppi. The saw may not be the fastest cutting saw but I believe it will give me the smooth and accurate cut I am looking for.

Jessica Pierce-LaRose
11-25-2013, 10:54 AM
5 degrees does not sound like much, I'm not even sure if I can see a 5 degree change in fleam or rake. I have real doubts concerning my ability to be that precise hand sharpening saws.

I don't know - it's hard to see 5 degrees on the saw, of course, but 5 degrees over the length of a file is rather evident. Maybe exactly 5 degrees is tough, but it's relatively easy to see that it's not perpendicular. Back of the envelope, over six inches, I think 5 degrees puts end a half inch off of perpendicular.

Kees Heiden
11-25-2013, 1:07 PM
Aargh! I always get the drection of rake confused, negative or postive. The Ulmia blades I mentioned were raked to the wrong side, shark teeth so to speak. Positive rake?

I even happen to have a picture. This is what you don't want on a mitresaw!

275759

Jim Koepke
11-25-2013, 1:55 PM
Aargh! I always get the drection of rake confused, negative or postive.

It confused me for a while. It is just the opposite of a bicycle's steering fork's rake. (used to be heavily into bicycles)

Now my way to remember is the slope of the tooth should "lean" back toward the handle.

My early filing of rip saws was to 9º rake. With the one that was just a saw plate and a shop made tote, the rake was set at 5º as was the fleam. The difference between it and my other saws is very evident.

For me, being willing and able to do my own saw filing has been educational by being able to actually feel the difference a few degrees can have.

jtk

Ron Bontz
11-25-2013, 2:10 PM
I don't know - it's hard to see 5 degrees on the saw, of course, but 5 degrees over the length of a file is rather evident. Maybe exactly 5 degrees is tough, but it's relatively easy to see that it's not perpendicular. Back of the envelope, over six inches, I think 5 degrees puts end a half inch off of perpendicular.

Sorry. To be clear. ( My opinions only ) I measure my rake from 12 noon clock wise as you are looking at the teeth in the vise. ( up side down ) positive rake will look like hooks to me. I should have also stated( on my back saws ) 0* to 5* MAX. on the rip filings. Larger hand saws are a different critter. So it varies with the saw. It is correct as well that the increased weight of the plate adds to the aggressive nature of the saw, and some of the older vintage miter saws I found to have about 10* to 15* rake, give or take a skosh, and 30* fleam. ( Dedicated cross cut ) Basically there are four ways to make a saw seem to cut faster or smoother and start easier, given the same saw plate. 1) Lower the hang angle giving it more forward force, easier to start, (Lower your hand on your plane tote and push instead of up higher.) 2) Relax the rake, giving it less dig in, easier to start (more scraping , less slicing 3) Add fleam to slice more and smooth it out. ( skew your block plane a bit). 4) File it with more, smaller teeth. ( A 1/4" chisel removes less material and pushes easier than a 2" chisel) Now throw all those methods in together and see what shakes out. AHHH:):) So in the end there are probably as many preferences as there are saw owners. http://i1179.photobucket.com/albums/x395/ronb19571/AseriesDovetailhighvslowcomparison_zps3b206caa.jpg Now that I have muddied the water even more. Enough said.

Kees Heiden
11-25-2013, 2:58 PM
Muddled? No not at all.

How about the LV dovetail saw. 14 tpi and 14 degree rake! The hang angle isn't very high either. That makes an easy saw. Not especially fast probably.
At the other hand, my new dovetail saw, also 14 tpi and a rather low hangangle, but 4 degrees of rake, is quite easy too. But it has a tapered spine and a canted blade, which I certainly feel like helpfull to smooth out the cut and making it easier to start too. So add that as nr. 5. ;)

Ron Bontz
11-25-2013, 4:53 PM
:):)Yeah. The canted plate just adds about a degree or so to the rake, making it a bit more aggressive. Not really noticeable, at least to me. It does however have an ascetic appeal and offers the illusion of cutting deeper on the front of the cut to avoid cutting too deep. I've said it before but the lee Valley saws are a great bang for the buck and a good saw. As you get better with them you can file them, or have them filed more aggressively to suite your needs. I edited the "Ramblings" a little to include the fact that each hang angle has a range of maximum functionality, depending on your preferences, etc. As far as the tapered spine. It lessens the toe weight slightly. On shorter saws 16" or shorter I found no substantial difference that can not be compensated for with 1* or 2* rake change. I use the tapered spines on my 20" Roubo saw, 1" down to .75". But while I can feel the difference in toe weight, the overall weight of the spine still seems centered on the plate for the most part. I have one more design to try yet. But another day. ;)

Hilton Ralphs
11-26-2013, 4:24 AM
Aargh! I always get the drection of rake confused, negative or postive.


You generally don't want a positive rake on a western saw. Unless of course you are literally hacking the poor thing to death.

Ron Bontz
11-26-2013, 6:41 AM
You generally don't want a positive rake on a western saw. Unless of course you are literally hacking the poor thing to death.

Correct. Sometimes I look at the saw too much upside down, I think. :(

Mike Holbrook
11-27-2013, 2:51 PM
That's the problem I have been having Ron, now I get it. All I have to do is stand on my head to think about rake and I should get it right, right?

I was just staring at the teeth on the Gramercy Sash saw under a magnifying light, maybe they do lean slightly more or less than 90 degrees to the front of the saw, but I don't think I can actually see it. The front (facing the front of the saw) of the teeth look 90 degrees to me. The hammer set makes them look like little waves breaking forwards, but it might be an "obstacle delusion". Since I have a hard time typing while "upside down" though, I may be getting it backwards.

The positive and negative thing seems to just confuse me more. I thought "positive' meant leaning more to the front of the saw tip, but wouldn't a forward lean make an acute or smaller angle to the front of the plate, which might be considered less or negative? I may have to learn to type standing on my head.

Hilton Ralphs
11-28-2013, 3:32 AM
The positive and negative thing seems to just confuse me more. I thought "positive' meant leaning more to the front of the saw tip, but wouldn't a forward lean make an acute or smaller angle to the front of the plate, which might be considered less or negative?

Mike, you're making the mistake of looking at the angle of the gullet and not the tooth. Concentrate on the tooth and then you'll see that a positive rake angle is indeed larger than 90 degrees.

Ron Bontz
11-28-2013, 11:15 PM
Finally back.. Not the best graphic in the world. But hopefully a little more clear. http://i1179.photobucket.com/albums/x395/ronb19571/NegativePositiveRake_zpsdc3eeaa3.jpg

Kees Heiden
11-29-2013, 2:53 AM
Aha, yes that's what I thought too! But sometimes these things are named counter intuitive.

Mike Holbrook
11-29-2013, 9:29 AM
There were two things that were throwing me off. One being which end of the saw plate is the toe and which has the handle, many pictures do not show a handle like Ron's does. I tend to look at saw teeth with the handle in my left hand and the tip in my right hand, the opposite direction from Joel's Sawtooth Design chart or Ron's chart above. The other was the realization that the angle is measured as degrees on either side of 90, 15+ vs 105, 15-, vs 75 (which just seems counterintuitive). Probably what Hilton is trying to point out? I think some people assume others know they mean negative rake simply calling negative rake "rake", causing some of the "less initiated" to misunderstand. I suppose if you look at the teeth from the point of view of a person sharpening the teeth the system makes some sense, but from the simpler view of just knowing what angle is being referenced from what other point not so straight forward IMHO.

Ron, thanks for illustrating things clearly.