5/16” / 7.9mm round files on .404

[Vintage Engine Repairs]

Grabbed a few massive 5/16” / 7.9mm round files to try out on .404 pitch Stihl chain.

If you haven’t cut Aussi woods you’ll think the tooth shape is completely wrong, anyone that has will understand the advantages of these 80+ degree top plate cutting angles.

Anyway, had a play around and I’m pleased - i think it should do well for what we need out here. I look forward to putting this file on some new chain I have coming for my 076 super and into some large aussi timber when it arrives and see how it acts. Watch this space

 

[trains]

Cut with it fresh out of the box, then hit it with 5.5 as per spec, cut a few more rounds.
then hit it with the 8mm file and see how it goes, again, just cutting cookies is not the full picture, its the time the chain stays sharp, and how much it puts in the trailer between sharpenings that count, and how smooth/ speed vs durability that makes this type of sharpening to your particular timber worth it.

 

[Westboastfaller]

looks like its time to drop down to 1/4 next file to maintain same angles without cutting out top of driver link or start coming up a bit.
Dam that's a big file. Chain probably calls for a 1/4" file anyways. No different than when I had fell for property development in second growth hardwoods in BC lower mainland. 1/4 on 7/32 chain in 3 to 4' hardwoods such as Maple and Cottonwood. No chomping through the wood just a smooth fast glide. 3/8 chain is all you need there.

 

[Vintage Engine Repairs]

looks like its time to drop down to 1/4 next file to maintain same angles without cutting out top of driver link or start coming up a bit.
Dam that's a big file. Chain probably calls for a 1/4" file anyways. No different than when I had fell for property development in second growth hardwoods in BC lower mainland. 1/4 on 7/32 chain in 3 to 4' hardwoods such as Maple and Cottonwood. No chomping through the wood just a smooth fast glide. 3/8 is all you need there.

Yes I recon you’re spot on, maybe one more file
with the 7.9mm then dropping down to 6.3 to the end of its life.

 

[buzz sawyer]

Interesting. Might try that on some of our dry Locust.
I thought the "top angle" referred to the angle between the side and front cutting edge of the cutter, not the cutting edge. 80 deg. would be almost straight back to the back of the cutter.

 

[Vintage Engine Repairs]

Interesting. Might try that on some of our dry Locust.
I thought the "top angle" referred to the angle between the side and front cutting edge of the cutter, not the cutting edge. 80 deg. would be almost straight back to the back of the cutter.

Hi, honestly I really don’t know, this is where I measured though lol. Stihl calls it “Top plate cutting angle”

 

[Westboastfaller]

Yes I recon you’re spot on, maybe one more file
with the 7.9mm then dropping down to 6.3 to the end of its life.

never seen a 5/16 in a saw shop. never had a use for one either as iv'e always used 3/8 chain so going up a size was to 7/32 for stihl or 1/4 for Oregon chain.
A good trick to do is alternate between file sizes if you file in the field. Lift the smaller file up to carve in higher so when you opt to go up a size the bigger contour file with only cut the cutting edge (with direction or the point of the gullet with i bit more effort). Just a few strokes a tooth if you only 'dusted out'. certain jobs or chain life you may find you can go back between three file sizes. save a lot of time and easy on the files. Good when filing in heavy rain with hard chain or a hard crust on chain.

 

[Westboastfaller]

Cut with it fresh out of the box, then hit it with 5.5 as per spec, cut a few more rounds.
then hit it with the 8mm file and see how it goes, again, just cutting cookies is not the full picture, its the time the chain stays sharp, and how much it puts in the trailer between sharpenings that count, and how smooth/ speed vs durability that makes this type of sharpening to your particular timber worth it.

yeah you have to look at it all and may all be different for the next job or strip. I LIKE to go a size up or file round chisel up into the corner in bigger wood for felling with the dogs on angled felling cuts. Nice and smooth but If you need to limb a lot or tip cut in general as well as bore and brush then it rarely became worth it for me.

 

[pioneerguy600]

Hi, honestly I really don’t know, this is where I measured though lol. Stihl calls it “Top plate cutting angle” View attachment 932218

There is two angles that affect the top plate on the chain, easily confused if the full name is not used. Top plate filing angle and top plate cutting angle, a tad confusing until one gets hand filing.

 

[davidwyby]

Interesting. I have a mountain of aus hard wood that’s been baking in the desert in SoCal for 20 years.

 

[Vintage Engine Repairs]

There is two angles that affect the top plate on the chain, easily confused if the full name is not used. Top plate filing angle and top plate cutting angle, a tad confusing until one gets hand filing.

Thanks for the clarity Jerry!

 

[Dennisthemenace]

Grabbed a few massive 5/16” / 7.9mm round files to try out on .404 pitch Stihl chain.

If you haven’t cut Aussi woods you’ll think the tooth shape is completely wrong, anyone that has will understand the advantages of these 80+ degree top plate cutting angles.

Anyway, had a play around and I’m pleased - i think it should do well for what we need out here. I look forward to putting this file on some new chain I have coming for my 076 super and into some large aussi timber when it arrives and see how it acts. Watch this space

View attachment 932183
View attachment 932181
View attachment 932184

Cripes! You recently convinced me to go up and try 1/4 on new 404 and now you have upped the ante again lol. Fortunately I can get 5/16 over this side easy but I notice we've skipped the intermediate stage - 9/32, I cannot see them available in Oz and definitely not worth the shipping from US.

 

[davidwyby]

I sharpen with a husky roller guide. When the rollers get worn the file gets lower and you get more hook. Same with going to a smaller file. One could build larger dia rollers or wrap them with tape to raise the file for more stay-sharp. Same with an Archer Fast Filer.

 

[Vintage Engine Repairs]

Cripes! You recently convinced me to go up and try 1/4 on new 404 and now you have upped the ante again lol. Fortunately I can get 5/16 over this side easy but I notice we've skipped the intermediate stage - 9/32, I cannot see them available in Oz and definitely not worth the shipping from US.

I actually think 9/32 would be better honestly. Yep I couldn’t get them here!

 

[Bwildered]

Grabbed a few massive 5/16” / 7.9mm round files to try out on .404 pitch Stihl chain.

If you haven’t cut Aussi woods you’ll think the tooth shape is completely wrong, anyone that has will understand the advantages of these 80+ degree top plate cutting angles.

Anyway, had a play around and I’m pleased - i think it should do well for what we need out here. I look forward to putting this file on some new chain I have coming for my 076 super and into some large aussi timber when it arrives and see how it acts. Watch this space

View attachment 932183
View attachment 932181
View attachment 932184

What you are doing is trying to reinvent the wheel and if it was any good everyone would have been doing it years ago

 

[Dennisthemenace]

I actually think 9/32 would be better honestly. Yep I couldn’t get them here!

You had to take something off the back of the rakers to get the file in?

 

[Dennisthemenace]

What you are doing is trying to reinvent the wheel and if it was any good everyone would have been doing it years ago

No harm in experimenting, at the least it will stimulate the file manufacturing industry eh?
If we follow your logic no one would have tried porting an OEM cylinder or tried a 7/32 file on new stihl 3/8 etc. I'm happy to watch a bloke have a go.... saves me havin to do it lol

 

[Huskybill]

Pretty close to what I do. I take the next size smaller file and cut back the gullet more under the tooth.

 

[Vintage Engine Repairs]

What you are doing is trying to reinvent the wheel and if it was any good everyone would have been doing it years ago

Reinventing the wheel? Don’t you go up a file size or down a file size or two occasionally depending on how you want to shape a tooth or for the wood you’re cutting? Nothing ground breaking here…

 

[Vintage Engine Repairs]

Pretty close to what I do. I take the next size smaller file and cut back the gullet more under the tooth.

Spot on, i tried exactly this yesterday with great results. Do you blend the slight transition between the two files?
Here is where I have blended the transition



and then when I haven’t