Chain grinder..

[john87]

2 minutes ago, AHPP said:

Are you old enough to have learned on Whitworth?! It's either that or your boss was German and you were making Obendorf Mausers.

Yes, i am not far off 61 now but i started with mechanical things when i was just a kid.  Whitworth and BSF were both 55 degree round root, round crest, so, if you screw cut them on a lathe you had to use a thread chaser [still got them here] to round the crests.

 

UNC and UNF were 60 degree round root flat crest, so more or less a metric thread form but in imperial diameters and pitches.

 

Did a lot with BSP too ]parallel and taper].. [steam fitting in the boiler house] Then we had the ISO metric stuff, cycle thread, acme thread. buttress thread, knuckle thread.. The americans had NF NC and NPT..

 

Still got a lathe now, a Harrison 140, and an Elliott 18" shaper and god knows what else.. Sadly got to get rid of them all now, but going to try to hang onto the lathe if i can..

 

Problem i got, is that stuff that was worth lots just 10 or 15 years ago, you have a job to give away now.. People like you that can actually use this stuff are very few and far between now. The youngsters now could not screw a nut onto a bolt, let alone make one..

 

john..

[Dan Maynard]

1 hour ago, Stubby said:

am one of the people mentioned who say give it 3 strokes every other fill up . That does not mean setting up a stump vice or removing the chain I mean sitting on a stump with the saw between your legs  and file free hand , just a tickle

Me too. I'm right handed but have taught myself to file the left hand cutters left handed, makes it a piece of cake as sit behind saw and do both sides.

[john87]

Do you all use them file guide things or just do it freehand??

 

john..

[Rich Rule]

 

 

freehand for me.

 

unless it is battered.  one of the guys i work with has a Swedish brand of grinder, sharpener.  works brilliantly, doesn't damage the tooth and is great for bring a damaged chain back into life.

[openspaceman]

On 24/08/2022 at 03:44, john87 said:

My first ever job was in an engineering works that did that "metal stitching" cast iron repairs. Part of the job involved drilling literally thousands of 1/4" holes, 2" deep in the cast iron to be repaired, and also in 2" thick steel plate to make the hourglass shaped repair inserts..

Magic stuff, far stronger than welding or brazing, dumbbell inserts on mine were nickel I think, back then I paid about £10/inch but the firms seem to have disappeared now.

On 24/08/2022 at 03:44, john87 said:

 

As an aside; In work they chuck away "magnifying glass on a stand with a light built in" medical type things from time to time. I should get one of them,,

 

Yes and replace the fluorescent tube with an LED one.

[openspaceman]

15 hours ago, john87 said:

Do you all use them file guide things or just do it freehand??

 

john..

I never used a guide but more recently with the 5/32 files and down I do as they snap too easily unsupported.

 

I'm not so good now, mostly lack of practice, but like @Stubby used to touch up frequently, it was amazing how sensitive you became to a slightly dull saw when production cutting.

 

I copied the other guys back then but never see people doing it my way nowadays. I straddle the saw with the bar slightly tipped up clear of the ground for left hand cutters and then rest the saw at 40 odd degrees across my thigh to the right hand set.

[lurch_917]

16 hours ago, john87 said:

Do you all use them file guide things or just do it freehand??

 

john..

i started with the origon guide but later moved to the husky .325 guide as it fits in the pocket nice and eazy .

[doobin]

As regards a machine not getting it as sharp as by hand- that simply isn't true, with the machine set up correctly and an operator who knows what they are doing!

 

It turns out that it's really hard to take a photo clearly showing a well sharpened chain, but I've tried. You can also see all the many angles of adjustment that a pro level grinder offers.

 

Re the 'burr' at the top- this is not an issue. It's simply the layer of chrome on top of the tooth peeling up as the hook (the inside top plate angle??) is set so fine. I've had conversations with 'old timers' in the pub who are incredibly proud of their worn file handle that they use to knock this bit off after sharpening to such a level by hand. This just does it a heck of a lot quicker.

 

CBN wheels are great, they cut well and are always the correct profile without needing to be re-dressed. They cut fairly cool, (and the ceramic ones Oregon ship with aren't bad in that respect either) but any abrasive working on such a small tooth will have a tendancy to overheat the metal if you go at it like a bull in a china shop. I'm going to experiment with the airline powered mister off the milling machine, misting the tooth with water as I sharpen.

 

Edited August 25, 2022 by doobin

[doobin]

Ok, so I tried the mist coolant with water. What an improvement. You can really hog it off, no light taps, and burr formation on the side plate is much reduced. This is going to come in handy for when I get the bandsaw sharpening wheel setup too. 
 

the chain is ice cold when it comes off. 
 

 

Edited August 25, 2022 by doobin

[peatff]

I sharpened 3 chains this afternoon with my Lidl electric chain sharpener, happy with the way it sharpens and the time it took. All the same pitch so all I had to change was the cutter length. I'll be out blunting them on the farm wood pile again soon.