Tutorial: make your own raker depth gauge supported by software tool

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hannes69

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A big hallo to all chainsaw sharpeners who like to build their own raker depth gauge!

In this thread I will show how easy you can make your own raker depth gauge, which has several advantages:


+ low cost

+ ‚personalized‘ gauge corresponding to your needs / preferences

+ no need for measuring equipment when raker filing

+ progressive depth approach

+ better linearity than typical buyable gauges

+ being proud of having another self-made tool ;)


First of all I have to thank BobL in this forum, whose thread https://www.arboristsite.com/commun...ly-progressive-depth-raker-generators.114624/ has inspired me a lot! He explains in his thread why we aim for a ‚constant cutting angle‘ and how we could realize that.

To my person: My name is Hannes, I live in Germany, more concrete in Bavaria, 200 miles away from Waiblingen, headquarter of Stihl ;) English is not my native language, I hope you´ll understand my wordings…

It´s a very short time I´m into the matter of chainsaws; last year my father died quite unexpected, so now the small ‚family forest‘ is my job and I hold my father´s good old Stihl 034 Super in honor. I renewed everything possible of the chainsaw, cleaned everything thoroughly and went then to the maintaining of the chain.

My profession is electric engineering, I like measuring, numbers, programming, repairing and tinkering with many things.

So I came across this wonderful forum here and found out many useful things about raker filing.

And in the same ‚perfect‘ manner like I restored my father´s chainsaw, I learned to sharpen my chain and now I wanted to do the same perfect approach according to the raker filing process.

It´s a shame that many chainsaw users still are used to throw away half-worn chains because they don´t cut as good as the new ones. A waste of money, bad for our environment (much of energy is needed when recycling metals), more unnecessary profit for chain producers, less fun and more effort when using a not so perfect chain.

So I invested some time to develop my perfect raker depth gauge. Of course I didn´t reinvent the wheel, but I tried to do my best to collect some information and combined it and give it a new structure.

The results are some self-made raker gauges, which are now in my personal use and now this thread including photos, explanations and a piece of software.

I´ll give this to you in the hope that it may be useful to some of you :)

For me the raker filing process shall be practical and parallel as perfect as possible. The method by using calipers, digital angle finders and so on leads to perfect results, but this way is not that practical to me. On the other side the buyable raker gauges are very practical but not that perfect: Like BobL showed, they aren´t perfect progressive, you have to live with the given ‚soft‘ and ‚hard‘ settings and maybe there are problems with different chain types (e.g. bumpers).

My first attempt of creating a raker gauge was of course to imitate the given ones, so I built one in the Stihl or Husqvarna style.

To get away from the trial and error process, I then took pencil and paper, made some drawings and did the math behind it. Then some Excel sheets and after that for usability reasons and out fun I packed the formulas in a self-made Windows application: the Raker Gauge Calculator.

After this lengthy theoretical section I tried some versions of the raker gauge and started to think about better approaches. The result is my gauge type 2 (type 1 is the Stihl / Husqvarna design).

Here´s a photo showing some of them: the two left ones are type 1 (the second one with joined raker cutouts), the three right ones are type 2 (the fourth one made from stainless steel)

1_allgauges.JPG

Both designs can be calculated by my software. That means: When knowing different parameters of a given chain (like raker – cutter distance, cutter height and so on), my tool calculates the resulting raker depths and cutting angles depending on cutter wear when altering the gauges´ design criteria.

So ideally you choose one of the chain presets so you don´t need to take measurements from your chain, choose the gauge type, and play with the gauge´s design numbers until you get the cutting angles you would like to have.

The software has several sections (tabs), one is the calculator itself, one tab shows the chain parameters graphically, one tab shows the gauges graphically and one tab contains some hints concerning the software and the gauges.
The following screenshots show the different tabs:

2_tabcalculator.jpg

3_tabchain.jpg
4_tabgauges.jpg

Download the zip file, unzip, run exe. Virus free guaranteed!


How are the gauges made?

I bought some steel plates from a normal hardware store, in Germany there are common 1.2 mm ‚normal‘ steel and 1.0 mm high grade steel (stainless). Here they sell them in 1 inch stripes, that´s an ideal width for a gauge. Next step is to cut off a piece 4 inch long, take a Dremel, angle grinder, hacksaw.

If you leave the gauge straight as it is now, maybe you´ll touch the chain with your fingers with a worn chain when using the gauge (see photo), so it is better to bend the gauge (like the Stihl ones).
5_whytobend.JPG

I did the first curve with my fingers and the gauge pressed into a vise, the second curve with the help of a hammer and a chisel because of the narrow distance between the two curves.

The gauge type 1 design can be created by using different Dremel bits, if using ‚normal‘ steel it even is possible to misuse a steel driller in a drilling machine as a milling cutter if you don´t own a Dremel.

My personal favorite is my creation, the gauge type 2 ;)

When looking at the numbers you´ll see that it is more linear during the cutters´ wearing life (see screenshot and compare with screenshot above)), due to its design it can be used with bumper style / safety chains (see photo) and most obvious it is VERY easy to build.

6_numberstype2.jpg

7_lowprofilebirdview.JPG

This one rectangular cutout can be made with anything, a hacksaw, a Dremel, an angle grinder or even a file, no special tools required.

Why are the numbers for this design better? Because of the LOWER pivot point.

The next photos show my raker gauges in action :)

You see type 1 (the one you should already know from different manufacturers) and type 2, not sitting like type 1 onto a tie strap but onto a rivet.

8_type1pivotpoint.JPG
9_type2sideview.JPG

These gauges are practical in use and from a practical point of view precise enough (let´s not say perfect ;) )

Why do the gauge manufacturers not use design 2?

Design 2 has one weakness: it has only 1 design criteria, the thickness of the material.

They prefer to use one thickness and use another design criteria that can be used for type 1, the criteria I call ‚pivot length‘, so the position of the pivot point.

So they can use one sort of metal sheet, and the design itself is no problem for mass production (laser cutting, …).

Maybe it would be difficult to sell such a simple design like my type 2, who would spend some bucks for a rectangular cutting ? ;)

So when using gauge type 2 we have to live with given metal sheet types or we have to discuss a way to alter the thickness of the material (this is not impossible, I´m thinking of at least two methods, one is hand grinding/polishing, the other one using acid).

By accident (or call it luck) the common 1.0mm and 1.2mm sheets work very well in combination with 3/8 chains.

And additionally you have one joker: you have more than one rivet on the chain to sit on with the gauge! For the 3/8 low profile chain I use the rivet directly after the raker, for the normal 3/8 chain one rivet farther away is the appropriate one.

One thing to mention concerning the bumper style chains: The gauge defines the level of the highest point of the raker. If you file away all the material parallel to the gauge, most of the bumper disappears ;)

The missing dimensions of the gauges´ cuttings that are not given by the calculator are dependent on your actual chain (pitch, gauge). Example gauge type 2, 3/8 chain, 0.063 driving link gauge: the cutting has to be 172 mil wide and 850 mil deep to make the gauge sit onto the rivet. The numbers don´t have to be that accurate, start with removing a little too less material and try the raker gauge, then progress with removing more material. The calculator doesn´t deliver these numbers, they are self explanatory when looking at your chain.
 

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So now, I give this knowledge to you, and maybe some of you can contribute to the project by the following things:

+ give feedback about different chain types. When I have a complete data set according to the software´s ‚chain‘ tab, I can integrate the data as preset into the software. Most interesting at this point would be a different chain pitch, I personally only own 3/8 and 3/8 low profile. For them I have measured the data with unprofessional equipment but much time and effort, I trust the numbers (the theoretical numbers show up in practice, at least for me…)
Maybe someone of you has professional equipment to do such measurements and could help me out in this regard.

+ give feedback about the gauges, the usage, the construction and so on, this could help other users

+ maybe the software tool needs some corrections, e.g. language,…, maybe you have suggestions, wishes ...


This all seems a little bit complicated, but in real life it could be as simple like that:

You own a chain listed in the presets of the software e.g. Stihl Rapid Micro 3/8 0.063. You choose design 2 and you like a cutting angle in the region of 6.5°. You buy a 1 inch wide stripe of 1.2mm steel, cut off 4 inches, make a rectangular cutting 172 mil wide and 850 mil deep and optionally bend the steel stripe for better gauge handling. That´s all.

The rest of this post is explaining a lot of things around that ;)

It should be a kind of addition to BobL´s thread and a logical consequence of it.

I hope you can make use out of it; that was my intention.

And sorry for this long post, explaining things in a short manner is NOT my strength ;)

Be proud of your new tool :)

And now it´s time to discuss that stuff hehe…

Hannes.
 
Wouldn't you have to make a gauge for each brand of chain?
Or one for each model chain in each brand?
Depends on the chain ;)
It mostly depends on the chain pitch and the chains´driving link gauge.
Of course a progressive raker depth gauge can´t be universal in this simple form.
My approach was to build your own gauge with very little effort, without special tools and in parallel being very linear.
Furthermore: Who uses personally many different brands, types, pitches and driving link gauges for chains? I personally own a Stihl 034 Super for the forest and only use one type of chain with it: 3/8 0.063 gauge Stihl. Beside that I own an electrical chainsaw for homeuse (if current is available) and for that purpose I use 3/8 0.050 gauge low profile chain. That´s it. Two different raker depth gauges.
I think many pros in the woods maybe use in parallel chisel and semi chisel chain, maybe one saw uses 3/8 and the other one .325 pitch, but that´s it.
And even if you own several different chains, I really don´t see a problem: 40 inches of the steel stripe cost me under 2 dollars, I can make 10 gauges out of one stripe, one gauge is finished in under 15 minutes...
The most interesting thing with my approach is, that you can adjust the raker to your personal preferences I think. Maybe you like a raker gauge depth of 30 mil with a brand new chain. Then you can create a raker gauge, that leads to a nearly constant cutting angle like the one of your new chain with 30 mil raker depth through the whole life of your chain, that´s the point.

Why not use one like this?
You can use one like this. But this is a constant raker depth type and NOT a constant cutting angle type.
With this one you can maybe maintain a constant raker depth of 25 mil during the chain´s life, but that leads to a cutting angle that gets smaller and smaller the more your chain wears.
Here the numbers for the constant raker depth approach, compare the cutting angles with the screenshots of the starting post!

constantrakerdepth.jpg

You see, that at the end of the useful life of a chain (Stihl Rapid Micro in this example) the constant raker depth gauge leads to a cutting angle of 2.6°, my gauge type 2 maintains at least 5.7° coming from a starting value of 6.3°! That means in simple words (and assuming some simplifications) that one chain has only half the cutting power of the other one at the end of life point.
Your decision what you prefer at this point ;)
Today all chain manufacturers offer these progressive types (Carlton, Husqvarna, Stihl, ...), there is a reason behind that. Even they confess now, that it is a better approach (though they´ll sell less chains because you will use it a lot longer because of the maintained cutting power).
So the historical development was this: First the method like "x file strokes every time I sharpen the chain", then a constant depth raker gauge, then buyable progressive raker depth gauges, now a better self-made version of the progressive gauge :) That´s called evolution ;)

One hint: Read BobL´s post first (that´s the reason I linked it immediately at the start of my tutorial), then a second time my tutorial, then maybe some aspects get a little bit clearer.
 
That I’m not smart enough to take advantage is my fault.
Hmm, I tried to write the tutorial in a manner that everyone who has the time and the few tools to make this raker depth gauge should be able to do so.
Maybe I tried to explain my way of finding out all about this topic and it is a liitle bit difficult to explain it to somebody else?
And I mixed two different aspects of this story together, one is to make a gauge, the other one is the theory behind it including the software part. But I thought that one aspect has very much to do with the other one...
I don´t know how good this tutorial will work out. It depends on the community here in the end. My software tool is version 1.0, there is room for improvement. If I get feedback about different chain types, I could integrate them into the software, so only a few people who deliver the data, would have to fiddle around with measurements and numbers.
Probably the process could be simplified, so when all the data is collected, a list could be published here, containing the different chain types combined with presets for a soft wood and a hard wood gauge. This would be the 'beginners mode' and the software with personal settings a kind of 'advanced mode'. Many things are possible in this field.
I personally took out very useful information for me from this forum and as a logical consequence (within my personal rules) I felt I have to give something back. And I decided by purpose to do that in this forum and go a harder way. It would be a little bit easier for me to post in a German forum, but I thought I´d like to go the 'big' way. The biggest forum regarding this topic, hopefully adressing many people, hopefully the possibility to help many people and the chance to develop this aspect of chainsaws further.
Of course there is the danger that this topic is way too special, complex, uninteresting for many people, but everything has its risk. I tried my best here, it´s not up to me what the community makes out of it. It´s an offer.

For me it is very simple: A chainsaw is a machine. And machines are made to be perfect (or as perfect as possible) in contrast to people.
I´d like to have the machine work as effiicient as possible, it does work for me, I get less tired, less burden on my bones and muscles. And the work has much more fun within it, when it´s running the way supposed to. I´m a beginner with chainsaws, but it took not much time to FEEL the difference between a proper tuned carburetor and a mistuned, the difference between a properly sharpened chain and a dull one and now the difference between properly filed rakers and rakers way too high.
I sharpened a Stihl chain these days with cutters weared 0.25 inch (so to speak 0.15 inch cutter left), the raker depth is now more than 50 mil (used my self-made gauge type 2 of course). I used this chain for cutting down a too high beech hedge (hard wood!), perfect behaviour of the chain. It felt absolutely the way it should, not too aggressive, no feeling of the nearing kickback or so, no rattling or bouncing. Absolute properly sized chips.
This topic has its benefit for me, and I´m only a hobbyist, it should even be way more interesting for professionals. You can work more efficiently, use a chain until the teeth break off, the raker filing process works better and faster with such a gauge.
 
Can someone bring you a loop of chain, with a brand that you have not seen before, and you will be able to measure the depth gauges correctly? Take one of those Stihl examples I put up. Could you measure one of those loops? Or would you have to craft a gauge to fit them?
 
Can someone bring you a loop of chain, with a brand that you have not seen before, and you will be able to measure the depth gauges correctly? Take one of those Stihl examples I put up. Could you measure one of those loops? Or would you have to craft a gauge to fit them?

I bet he would only need a small section of a given chain to get his measurements.

Hannes be patient with us. Some folks don't check in but every few days or weeks. Threads and topics like this 'pick up steam' over time. It may take a while to get rolling.

I am a 30+ year career arborist who does not do near as much cutting as some do.

This is a great topic!

Thanks,

Dan
 
Can someone bring you a loop of chain, with a brand that you have not seen before, and you will be able to measure the depth gauges correctly? Take one of those Stihl examples I put up. Could you measure one of those loops? Or would you have to craft a gauge to fit them?
Of course I could measure these loops. It is not a trial and error process, so no fiddling around with the following built gauge. It´s plain geometry. Look at my software tool - tabs 'calculator' and 'chain'(or look at the second/third pic of the starting post). You see: you need 4 measurements of the chain when using gauge type 1 and additionally the two greyed out measurements and a variation of the cutter´s height for gauge type 2 so totally 7 measurements to complete one chain´s data set.
It was one of my wishes to the community here that I posted in my second post here: Give that data to me. I personally won´t buy all sort of chains, all brands, all types, all pitches, all driving link gauges. I already have measured two common types of them, 'normal profile' 3/8 and low profile 3/8. It is not very useful to send me chain samples to measure them (though you could do that). Because: Many of you can measure it on your own. The only really tool I used for that purpose was a digital caliper (any 'analogue' one serves as well). The rest consists of some helping tools, straight edges, bent metal stripes and so on. Everyone has other tricks to do such measurements as precise as possible. Maybe photos of the chains and measuring this 2D projections on the computer could partially work as well. What I hoped: Maybe someone of you uses something like a 3D scanner in his job and could use that for some chains... This would be the fastest and most accurate way of doing such measurements.
Beside that: Hopefully there are some simplifications we could make in the future (when knowing more about different chain types). E.g. I have now a data set for a Stihl Rapid Micro 3/8 0.063 gauge. We can leave alone the driving link gauge because this number has no influence on the 'real' matter here, the constant cutting angle, it only influences the width of the depth gauge´s cutout. So I have a data set for a Stihl Rapid Micro 3/8. I don´t own chisel chains, only semi chisel. So someone of you could hopefully now confirm my assumption, that Stihl Rapid Super 3/8 is really the same chain like Stihl Rapid Micro 3/8, and really only the cutter´s shape is different (the 7 and ? thing) and all the measurements are the same. That would mean: We already know the numbers for Stihl Rapid 3/8.
Furthermore: Someone of you owns the duro versions of this chains and the '3' versions like RD3 or RM3 with the bumper style. And hopefully confirm my assumption, that the measurement numbers are still the same (meaning these types of chain all share the same cutter and tie strap dimensions, they only differ in material or the type of driving link (normal or bumper/safety). That means: We already have the numbers for Stihl 3/8 (when I say 3/8 I mean 3/8 'normal' profile, otherwise I call it 3/8 LP for low profile).
The biggest question for me is, how similar the same chains of different manufacturers are. Of course there will be some variations in the measurement numbers, but are they really significant? If the variations lead to a difference in cutting angle of +/- 0.3° or maybe up to +/- 0.5° I consider this insignificant. So maybe we already know the numbers for '3/8' ? At least some posts in this forum here indicate that when people reporting the use of e.g. a Husqvarna raker depth gauge with a Stihl chain successfully or vice versa.
So maybe we are soon in the same ballpark like the big manufacterers, they offer 5 different depth gauges according to pitch (1/4, .325, 3/8, 3/8 LP, .404) and that´s it. That would lead to 10 different gauges out of my software tool, when maintaining the two types. And beside that my approach especially with the software tool makes it possible to aim for a personal preference of the cutting angle and maybe allow calculations for very exotic chain types.

I bet he would only need a small section of a given chain to get his measurements.
One cutter, one driving link, one tie strap in the right order that´s sufficient.

Hannes be patient with us. Some folks don't check in but every few days or weeks. Threads and topics like this 'pick up steam' over time. It may take a while to get rolling.
Good point :) As well as not being capable of describing things in a compact manner, patience seems not to be a strength of mine ;) It´s exactly my hope, that this 'steam' (very nice wording!) is coming in the future.
My goal is in the end, that every chainsaw user uses his chains till the bitter end until the teeth are breaking with maximum cutting power through its life span with the help of the right gauge ;)

Well, if you use a system that requires re-engineering a gauge, every time a different chain comes your way, that would make it hard to want to use.
It´s all a matter of preference of course. And balancing some aspects. Like with medicine: the desired effect and the not so wanted side effects. No one promises here the 'all in one wonder'.
See the top of the starting post, I already mentioned the advantages of my approach. When offering something new, it is common to tell about the advantages first. And of course it is a matter of fairness to look at the disadvantages as well, why not?
Disadvantages that come to my mind:
- no all in one raker depth gauge for all different chains on this planet
- no perfectly linear cutting angle
- some skills required for using certain tools (calipers, angle grinder, Dremel, file,...)
- some tools required (see above)

For me personally and hopefully many others, the advantages outweigh the few and small disadvantages.
And in my opinion the disadvantages are really small, because:
- there is no oneforall raker depth gauge because it simply is not possible. As well as there is not 1 type of chain for all possible applications.
- the cutting angle is not perfectly linear, but 'in the field' it should really be sufficient linear.
- a person capable of using a chainsaw should also be capable of using 'standard' tools like an angle grinder or calipers (at least in my world)
- some tools make life easier, but they aren´t a hard requirement. For my gauge type two you really only need something to cut away a piece of a metal stripe and then you could theoretically use a file to make the rectangular cutout. The bending is optional. You even don´t need to measure something, you can remove some material, try the seating, remove more material and so on until it fits perfectly. So maybe a hacksaw and a file needed.

And quoting you once again: "every time a different chain comes your way". What sort of usage profile is it, that you have to deal with many many different chains? Maybe a professional chain sharpener? ;)

Any new ideas and/or tutorial, should be able to withstand simple questions and/or obvious observations.
Absolutely. I´m a very critical person myself, so criticism is welcome.
I´m not after getting only praise. And I consider this topic here now in a work in progress state. There´s always room for improvement. And I don´t have the opinion that I have the perfect approach for this topic. I have found the perfect approach for my personal needs and setup and I want to offer this solution to the community here. It´s up to you in the end, if it is also the perfect solution for you or not.
Some are happy by using the 'x file strokes every sharpening' method, I´m ok with that. I´m ok with people that use a digital angle finder and so can maintain a perfect cutting angle and don´t need to touch the cutters with a metal tool. I understand that. Though understanding these methods, I don´t use them because I have other preferences. I don´t want to convince or persuade anybody here, because the method itself is convincing ;) ;)
 
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