Electric Racing Chainsaw Build, Help Please

[speedmd]

- In regards to chain grinding, pretty much everything has been attempted to enhance the cutting efficiency of the 404 high tooth chain.

Given the break in most competitions at the moment, some longer term details to pass along on the topic of steel selection for ultimate steel cutter tooth. It would be a big project to make cutter teeth and rebuild or make chain but several folks that I respect tremendously have suggested CPM- S110V for unmatched edge forming and retention when I recently talked to them. In searching, it does pop up in the knife world. When properly hardened, it does appear hand filing would require diamond files.

 

[Hillhater]

Speedmd.
I do agree that the chain , tooth, material, grind , etc is critical to the performance of the saw..
And, Im not saying there are not better option available, but i would be surprised if Stihl, Husk’y etc, have not done a LOT of research and testing , even just for regular commercial chains,...let alone the special custom “racing” chain.
You can certainly buy off the shelf Ceramic and diamond tipped chains for specific high duty commercial applications
I wonder how this project is progressing ?

 

[speedmd]

Most likely all this stuff is on a glide path until c19 settles into a steadier state of affairs.

As far a cutting is concerned, most old time wood workers and chefs can tell you that nothing cuts like sharp high quality steel. Carbides, diamond, ceramics will certainly out last and able to cut more abrasive materials much longer before going dull, but that initial cutting efficiency is unmatched by the best steels that will form a super sharp edge. In this app, durability is secondary in a 10 second max competition in clean soft woods.

Stihl would never consider something in the top of the list I posted above as they are some 50- 100 times the cost per pound of what they are using now and require exotic heat treat to get the best properties. These steels would most likely not be accepted by anyone that hand files to sharpen. Standard files would just squeak past and not be able to bite in on anything in the 62RC and above hardness that these will harden to.

 

[Ianhill]

Was thinking this the other day while watching forged in fire, whats the general grade of steel and finish as I can sharpen my chain with a hand file I need this old tonys toughness tester see where a standard chain sits on the toughness scratch test.
An overly toughened chain is useless for the general saw user needing a lifetime of longer than a few seconds but I suppose a one time cut chain could be finished in such a way that it doesn't matter if a file skates over it there's no maintenance to be done other than arc furnace recycling.

 

[speedmd]

Once you get above the 57- 58 Rc hardness, conventional files skate across the surface of most steels. Some alloying elements will help create this skating effect. At 60 Rc, you are getting into needing silicon carbide stones to efficiently cut into most hardenable steels at hand speeds. Many steels will not get this hard regardless what you do. Carbon content is a major key.

Toughness is the ability to take impact and that suffers the harder you get. The other test they do often on the forged in fire series is a bending test. This also suffers with increased hardness and why most knives are kept in the lower 57- 58 Rc range.

Saw chain is a compromise. On most quality saw chains, a lower carbon steel (soft enough to file) is used so it will stretch -bend rather than break, and the cutter links at slightly harder and are chrome plated to give them a harder edge. Chrome is much harder (up to 70 Rc) but its thinness (typical hard chrome .001-.003") still allows files to work. Edge quality suffers a bit and as many have experienced, always leaves a bit of a feather (burr) after sharpening that dulls or rounds off the edge quickly. Older wheel grinders would allow you to reverse grinding wheel direction to help reduce this burr. A dremel tool is great tool for real hard chain that your not cutting into with the hand file.

Once the edge is rounded slightly, it needs a touch up. If the corner -edge will not catch your finger nail with slight contact, it is dull. If you want the most durable chain, the ones used in demo or by fire departments are a option as Hill mentioned before. They braze a thin carbide shim to the top of the cutters. You need diamond files or diamond wheels to sharpen them and you need to keep steeper (more square) grind angles as the edges get brittle if tapered too thin. Their efficiency suffers a tiny bit because of this, but they will cut through wood with nails in it for a bit and not seem phased by it.

As far as hand vs machine sharpening goes. Always, the best edges -with max hardness maintained, will be gotten with hand speeds. Wheel grinding to get close, and finish by hand if you want the best - fastest cutting edges.

 

[harwester]

hard to read but drive link spacing is twice saw chain pitch.

thank you so much for this cool details.

 

[ZeroEm]

Was wondering about Astro Flight astro motors. They build to suite your needs.

 

[Ianhill]

Ive been using the erbauer battery saw for over a year now and can not complain power wise its decent batterys last well too only issue ive got is the nanny esc slow ramping the throttle at the start.

Im tempted to fit a vesc in there and max the batterys out, i got a flipsky vesc 6 sat around doing nothing ive got the bluetooth adapter too so the saw could be adjustable on the fly with a smartphone, im gonna open it right up next service time and see how much room the electronics take up how feesable is it to up the power a little and make the throttle response quicker battery time will suffer but i get loads anyway ive never gone under 2 of 4 bars with the effort my area needs so theres a bit if spare power to tap into without effecting my use case.