Sharpening Thompson Gouges.

[Sawdust Maker]

I bought the 5/8 U for roughing down
Have to admit I wasn't impressed when I used it. no cutting action on the tip. Had a closer look, hadn't quite ground it down enough (And no I haven't handled it yet)
Just goes to show, must wear glasses (god I hate the declining eyesight of middle age)

[rsser]

Nick, you can look forward to adding some hearing loss to the mix too.

John, will do.

[rsser]

Just one comment about Doug's fine tools, which may or may not apply depending on the heat treatment process.

has warned that the tip of HSS tools can be weak as a side effect of that process so don't judge the edge quality until you've ground a few mm back.

I say this cos I was experimenting with honing out the milling marks on the shallow detail gouge using the Tormek profiled wheel and their 'toothpaste' ;-}

I rolled off the leather, the tip hit the plastic and chipped out.

No drama, cos it was destined to be reground using std Tormek settings.

Best match I could achieve was 75mm projection, hole A on the TTS, and JS 1.

Off the coarse graded Tormek, I then worked at honing the bevel with the toothpaste and found it didn't do much on Doug's high vanadium steel (and I'm repeating this cos I see Doug is logged on ATM.).

[Doug Thompson]

Erm,
Personally without any fact to back it up it does seam like tools work better when they have been ground a couple times... it could be as simple as the grind changes so they feel better but I don't know. The edge chipping normally doesn't happen even when steel hits against steel. This steel has a complete heat treatment from the hardening to tempering and the cryogenics more than any other steel on the market today but I think there is a way to make it better... time will tell.

[rsser]

Doug, please don't take my post as a criticism. It's not.

is a production turner who goes through HSS tools at a rate of knots, so his experience counts for something. His favoured steel is Henry Taylor which is far from rubbish.

FWIW, when I first installed and used a Hock A2 Cryo blade in a Stanley handplane I got a chip in the edge, and I wasn't being ham fisted.

[Doug Thompson]

Ern,
I do understand and thought nothing wrong... at times I just don't have a answer why something happened.

What I do know is I found someone who can push this steel a bit farther so testing is being done right now to see how far it can go.

[Sawdust Maker]

Nick, you can look forward to adding some hearing loss to the mix too.

John, will do.

eh? what's that you say?
I'll be ordering one of these soon, probably the only thing covered by health insurance

Attachment 157002

[rsser]

Cool.

Whack a stocking-ette over the funnel to keep the chips out ;-}

[rsser]

Just to add a comment or two, as there's been posts elsewhere as well ...

The 5/8" U gouge is a tool I'm still coming to grips with.

The closest Tormek settings I could get are JS4, 65mm projection and A hole on the TTS. But you need to emphasise tip grinding to avoid a concave wing.

The 1/2" shallow detail gouge is a gem; prob the closest to a long and strong that's come out of the new world but others are more qualified than me to judge that.

Tormek settings for that: JS1, 75mm projection, A hole on the TTS.

Thanks again to Neil, Nick and Doug T.

[Sawdust Maker]

Ern

can you post a piccy of the end of the 5/8 showing the grind please

[rsser]

Here you are Nick.

And a front view of the orig. grind can be found here

[Doug Thompson]

Ern,
Here's another thread about grinding... I don't have time to copy and paste this over here but you can.
Bowl gouge basic grind profile

[rsser]

Thanks Doug.

[NeilS]

I have found this maxim very helpful since I first heard it from Doug.

Notice the basic shape of the flute is carried over to the grind, if you look down the flute and straight down on the grind the shape won't be perfect but very close. The wings will be ground to this profile and the gouge will work like a charm, small changes like grinding the wings back won't affect the tool much at all but major changes the tool won't cut. This basic idea can be used on any bowl gouge....

Here are photos by Doug of his two flute types that show the pilot grind to establish the profiles.

Attachment 158354
Attachment 158355

And here he has completed the bevels on one side.

Attachment 158374

And here the bevels on both sides.

Attachment 158361

And to illustrate further, here are some pics of two of my gouges, first pair is a Thompson 'V' and the second a P&N 'U' flute.

Attachment 158356.....Attachment 158357


P&N End.JPG.....P&N Top.JPG

I use slightly longer wings on the U flute than specified, but the bulk of the tip meets the maxim.
.

[Sawdust Maker]

Ern

Thanks for the piccy

Neil

Thanks as well

Here's mine as used on the weekend to rough shape some silky
I need to take a little more off the wing towards to top.

Attachment 158362

My Tormek settings were/are: JS 2, 65mm projection, "A" hole on the TTS

I've also attached Ern's piccy again for easier comparison

Attachment 158363