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smidsy
12th Nov 2004, 03:00 AM
Hei Guys,
I know you can buy chisels but I have more time than money and I quite enjoy making my own - aside from the satisfaction, it impresses the hell out of the newbies at my turning club.
I've made a couple of scrapers which work well, and now I would like to make a high sided bowl gouge.

Carbatec sell round tool steel blanks, but the problem is that I need to cut a notch about 150mm long up the middle of the blank and I don't have any specialist metal working gear apart from the usually stash of grinders.

I am thinking one of those mounting bases you can get to use a 100mm angle grinder as a drop saw, with a drill press vice mounted on it to hold the blank.
Obviously I would need to take small cuts, use a coolant of some kind (radiator coolant works well but stinks) and be carefull about heat.

Has anyone ever tried this, does my idea sound feasible.
Cheers
Paul

rodm
12th Nov 2004, 04:24 AM
I would be careful about using a conductive coolant with a 100mm angle grinder. It would be like using your grinder standing out in the rain. Radiator coolant is not the product you should be using as there would be little benefit in it's slightly higher boiling point compared to water. Coolant for metalworking is a soluble oil that provides lubrication that reduces heat from friction as well as having a cooling effect. Grinding disks are manufactured for wet or dry use and I haven't seen a wet disk for a 100mm grinder yet - not saying they are not available though. Another problem is that unless you can slide the shaft along it's axis the cut will be a series of dish shaped gouges. The profile will be a straight sided flat bottomed grove rather than countoured to the shape of the outside.
Sorry that I have bagged your idea but the only solution I can see is a milling machine using a rounded carbide cutter.
I knew a turner that made all his chisels by gringing the teeth off and shaping old metalworking files. That was until he hung a bit too much file over the rest and had one snag and then snap. He was working with a fairly large blank and had a long handle attached. Fortunately he wasn't hurt but there was a lesson to be learnt - somthing along the lines of use the right tool for the right job.

Alastair
12th Nov 2004, 11:09 AM
Smidsy

Some views and previous experience.

In my learning (and impoverished) days, I did a bit of this, as I could not afford bought tools. In addition, back where I came from, the price of (imported) tools was exorbitant. (about 5 times P&N, as a %age of average earnings.), so a few people in the woodturning fraternity had explored this to an extent.

Firstly, while not HSS, a fairly good grade of high carbon steel is used in spring manufacture. I made acceptable scrapers by cutting out of sections of leaf spring. Use an angle grinder, and work slowly to avoid losing temper.(of the steel too!).
Spring steel bar, (I bought a scrap front suspension anti-roll bar, and have used the spring steel bow leg from a camp stretcher) can be used to make bowl gouges. I gripped the bar in a vise, and ground a small flat (3mm wide) along the proposed flute length. Then, using 100mm gringer, with a metal cutting disc, and grinding carefully, hand held, with the disc on edge, slowly and carefully carve the flute in, using the pre-ground flet as a starting point. Slowly is the watchword. Cool frequently. Watch the depth and evenness of the groove, as it is easy to gouge too deep. By angling the disc to left and right, it is possible to adjust the profile of the flute, but the minimum radius is pretty well set by the thickness of the disc. I still occasionally use one of these tools for small and light work. Others have been replaced by P&N, but have been passed on to a friend who is starting up, and are still in use.

For the more advanced, HSS will retain its hardness up to silver soldering temperatures. In a prevoius life, one of the club members would buy short sections of exotic HSS bar, and pay to have the required profile cut using a CNC plasma cutter (I think!). This would then be silver soldered to a carbon steel bar for length and strength. I have lost contact with the club, but could try and locate, if someone was interested.
Similarly, a 1/8" layer of HSS can be silver soldered on top of mild steel flatbar, and ground to yield excellent scrapers, especially for those exotic curved and hooked scrapers, which break my heart to make by grinding away all the expensive HSS I have just paid through the nose for.

Hollowing tool tips, (a la Soren Berger) can be home ground out of HSS bar. My sizing tool (8mm square rod) parting tool (1" X 1/8") and heavy section square skew chisel (1/2"x1/2" bar) have all been ground up from HSS blanks.The "swan neck" shaft for my hollow form tool was home forged from 5/8" mild steel roundbar, and there are other projects in the pipeline, mostly fuelled from stinginess :)

Just to finish up, all my first 5 years of turning was done using a set of carbon steel gouges which had been hand forged from mine drill steel by my blacksmith grandfather, in the '30s. The roughing gouge was only replaced with a bought one 2 years ago, and I used the parting tool on a tricky job just weeks ago.

Finally, like most of us, I have used files as scrapers. I have been lucky, but using a brittle hardened steel, which has been specifically pre-made with a couple of hundred incipient cracks on the surface, is best described as a high risk venture!

Regards,

PAH1
12th Nov 2004, 11:49 AM
Woodturning magazine had an article on Ashley Isles method of manufacture a couple of months ago. Basically a thin grinding wheel was shaped to the required inner profile and that was then used to grind the inner groove and was done dry!!! Aparently it is a bit of a myth this make HSS blue and you have removed the tempering, you really need to go above 1000 degrees to do that. I do not see that the method would not work and have thought of doing the same for myself. I would definitively stay away from any file, way to easy to snap and HSS blanks are not that expensive from places like Gary Pye.

smidsy
12th Nov 2004, 05:29 PM
Hei Guys,
Thanks for the input.
The reason I used coolant instead of water is that I'm thinking of the corrosion issues of water and I used coolant because it has corrosion inhibitors in it.
Of course you need to be careful with any liquid around power tools but with care it is safe.

I've only made two chisels so far, but I only use tool steel blanks, all the files I have are good english and australian ones from my father which I wouldn't sacrifice on a chisel - besides, the tool steel blanks are fairly cheap.

The idea of shaping a brinding wheel to the profile sounds like a good idea as I have about half a dozen bench grinder wheels floating round my shed.
It is all food for thought.
Cheers
Paul

Wood Butcher
13th Nov 2004, 03:03 PM
I have recently finished a metal machining course at tafe and had a substantial number of HSS tool blanks left over. They are about 2 inches long and 1/4 inch square. To make long boring bars I drilled a hole large enough diagonally through the end of a piece of round bar to take the HSS. A grub screw in the side and mount the other end with a handle. I know the my description is rough but dad has my digital camera in sydney so i can't take any photos at the moment. I will post some photos when i get the camera back.

rsser
13th Nov 2004, 04:37 PM
I've bought a few HSS blanks from Garry Pye or McJing over the web and shaped them for scraping. Takes a while though on a white wheel.

goodwoody
13th Nov 2004, 07:31 PM
Scraper can easily be made from the appropriate sized mild steel bar and have your local welding fabrication shop simply weld on the end 8-10mm or chromium hard facing. When you have finished grinding this off in about 3years take it back and start again. Bloody simple.

smidsy
13th Nov 2004, 08:03 PM
Carbatec sell the tool steel blanks for between $8 and $25, so for a scraper it's not worth the hassle of welding.
I've made two scrapers so far, a standard 10mm curved end scraper and a 25mm scraper with a straight end but with the cutting edge extending about 50mm up the left hand side of the blade.

All I did for sharpening was use an existing scraper to get the angle and it took less than 5 minutes to do each one.
Cheers
Paul

RETIRED
13th Nov 2004, 08:54 PM
I've bought a few HSS blanks from Garry Pye or McJing over the web and shaped them for scraping. Takes a while though on a white wheel.
Ern, if you use a metal cutting wheel in an angle grinder to rough shape it is a lot quicker.

rsser
14th Nov 2004, 08:23 AM
Ern, if you use a metal cutting wheel in an angle grinder to rough shape it is a lot quicker.

Nifty. Cheaper too I'd guess.

And you control the heating effect in the same way by dipping into water?

RETIRED
14th Nov 2004, 07:48 PM
Never, Ever Not no How dip HSS tools in water. It can fracture them.

If they get hot let them cool on their own.

rodm
15th Nov 2004, 02:36 AM
,
So that is a definite no then? ;)
Not disputing what you are saying but that is the first time I have heard not to quench HSS in water. I sharpen a few HSS lathe and milling flycutter bits (1/2 inch square toolsteel) and the method of shaping and sharpening is to quench often.
Ahhh the penny might have just dropped. By quenching often I do not let the HSS overheat (blue) so the temperature variation is unlikely to cause internal fractures.

RETIRED
15th Nov 2004, 10:13 PM
,
So that is a definite no then? ;)
Not disputing what you are saying but that is the first time I have heard not to quench HSS in water. I sharpen a few HSS lathe and milling flycutter bits (1/2 inch square toolsteel) and the method of shaping and sharpening is to quench often.
Ahhh the penny might have just dropped. By quenching often I do not let the HSS overheat (blue) so the temperature variation is unlikely to cause internal fractures.
That is the key if you do quench. Most turners because of where the tool is held while sharpening (away from tip) they quench it when it gets too hot. Better not to quench.

rodm
15th Nov 2004, 10:42 PM
Thanks
Small bits of toolsteel do get a bit heavy to hold after short busts on the grinder.

rsser
16th Nov 2004, 06:31 AM
And if you wanted to make up some small scraper bits to fix to a mild-steel bar, what would you use?

Have heard of old electric planer blades being cut to size.

What about old rotary saw blades?

And for a non-engineer, fixing by silver solder or CA?

RETIRED
16th Nov 2004, 03:20 PM
And if you wanted to make up some small scraper bits to fix to a mild-steel bar, what would you use?

You can buy tool steel(we know it as HSS)at most engineering suppliers in all sorts of shapes and sizes. If you have a tame engineer you can probably get his old ones but most use tungsten these days.

Have heard of old electric planer blades being cut to size.

Yep, so have I and I do. :D I use them mainly to make form tools.

What about old rotary saw blades?

Dunno. :o

And for a non-engineer, fixing by silver solder or CA?

Silver solder. Heat breaks down CA.

rsser
16th Nov 2004, 04:16 PM
Thanks .

Cliff Rogers
17th Nov 2004, 01:36 AM
Hey Paul,

There is a difference between quenching & cooling & getting dirty.

Quenching is when you dunk something that is 'very' hot.
Cooling is that & also dunking something that is not 'very' hot.

Edit note: I got the bit below backwards, sorry about that. :o
...........................................................................................
Here's how I understand the way it works....
If you get it red hot & DO NOT dunk it but let it cool naturally,
it will be at it's hardest. (this should read softest :o )
...........................................................................................

If you get it hot enough to show colour on the surface & then dunk,
you will temper it to something less than 'as hard as possible.'
The colour at which you dunk (quench) determines the hardness.

Try using compressed air to cool as you grind.
Direct the stream of compressed air onto the cutting point as you grind.

I also reckon that it works for sanding, it keeps end grain cooler &
it keeps the sandpaper cleaner for longer.
Try it, you'll be so glad you did. :D

arose62
17th Nov 2004, 10:10 AM
That's the opposite of what I understood - (and this doesn't apply to all metals, btw)
from a google search ....

Heating the metal above a critical temperature (usually red hot and non-magnetic) causes this iron carbide to mix uniformly with the iron in a non-crystalline form (called austenite). Slow cooling at this point (eg buried in wood ash or lime) results in a soft layered crystalline structure and is referred to as annealing. Rapid cooling in water or oil results in a very hard crystalline structure (called martensite). The creation of either extreme requires, however, heating to the critical temperature first to form austenite.

Cheers,
Andrew

vsquizz
17th Nov 2004, 10:48 AM
That's the opposite of what I understood - (and this doesn't apply to all metals, btw)
from a google search ....

Heating the metal above a critical temperature (usually red hot and non-magnetic) causes this iron carbide to mix uniformly with the iron in a non-crystalline form (called austenite). Slow cooling at this point (eg buried in wood ash or lime) results in a soft layered crystalline structure and is referred to as annealing. Rapid cooling in water or oil results in a very hard crystalline structure (called martensite). The creation of either extreme requires, however, heating to the critical temperature first to form austenite.

Cheers,
Andrew
Pretty much on the money for steels but it will depend on the amount of carbon in the steel. Mild steel which has very little carbon will not be significantly affected by the heat treatment. The formation of Martensitic grain structure will occur on carbon steels (such as tool steel) on rapid quenching. Some carbon steels cannot be normalised to an Austentic structure due to their high carbon content, Cast Iron is one such.

A typical treatment for a cold chisel was tip to dull red and quench in water then heat until tip was straw colour and quench in oil thus Hardening and Tempering. The trick being not to heat treat the body of the tool as you want this to remain as malleable as possible.

Fascinating stuff really:D

Cheers

Cliff Rogers
17th Nov 2004, 12:31 PM
That's the opposite of what I understood - (and this doesn't apply to all metals, btw)

...

Arh yes, I think I got that a over h... :o
Sorry, other way around.

Alastair
17th Nov 2004, 01:11 PM
To confuse further, while the above is true for high carbon steel, the HSS which we are talking about has completely different characteristics WRT hardening and tempering.

If there is a guru out there, I would be interested to learn!

vsquizz
17th Nov 2004, 04:16 PM
Alastair, Not guru but have had some training. The above is generally true for Medium Carbon Steels such as those used for making hand tools and things like axles etc. The problem with HSS is that it is an alloy and the alloying components resist the old blacksmiths methods of hardening and tempering. The beauty of HSS is it resists tempering and can continue to function at red temperatures (more or less). HSS as we know it essentially gains its characteristics by the addition of Chromium and Tungsten, both elements which are noted for the performance at elevated temperatures. The addition of vanadium further complicates the ability of the novice to apply effective heat treatment.

Tempering will need to be conducted over many hours with air cooling only to follow. Hardening is conducted from near melting point and will depend on the amount of carbon and the martenstic/austentic structure fromed by complex carbides. In short, without a chemical analysis of a particular manufacturer's HSS then a hardening and tempering recipe is difficult to prescribe....but good old trial and error has been successful in the past.

My though is if it aint broken don't fix it.

Cheers

bdillard
21st Nov 2004, 09:05 AM
Me Too!

Hello Smidsy. I happened upon your posting (and this message board) while on a quest to determine the feasibility of grinding flutes in bar stock so that I might make a gouge or two.

I recently acquired some very nice tungsten alloy (not quite sure of the exact composition) 3/4" bar stock at a US Dept of Energy surplus auction. This stock was utilized for custom tooling at one of the Oak Ridge nuclear weapons plants, and I suspect it will be very suitable for woodturning. I'd prefer it be put to use manufacturing bowls rather than nukes (although I recognize the utility of each). But grinding the flute is not something I can accomplish with the tools I have.

I have contacted a variety of shops with milling equipment, but I'm told grinding is the way to go. I understand the flutes are ground with wheels similar to those found at manufacturer Georgia Grinding Wheel: www.georgiagrindingwheel.com (http://www.georgiagrindingwheel.com/) . However, Georgia Grinding are damned proud of their product, and I find the cost prohibitive for the limited quantity of flutes I want to grind.

Anyone here aware of someone who owns one of these wheels, or one similar; someone who might be willing to do some grinding for a fee? Or is there enough interest here perhaps to contribute to the purchase of a "community wheel" that we can ship from contributor to contributor?

What do you think of shaping to the desired profile (-s) a standard flat wheel using a wheel dresser?

smidsy
21st Nov 2004, 08:57 PM
Welcome to the forum.
I think shaping an existing wheel is the way to go, but the sides of the gouge I wanted to make (a high sided bowl gouge like the Hamlett) are angled so I would have to address the issue of wear on the grinding wheel.
This forum is mainly Aussie members so I doubt that you'll find anyone here that would have such a wheel. You might like to check out the newsgroup rec.crafts.woodturning, from what I can see this is mostly uS members so you might someone there that has a wheel or would be interested in sharing the costs.

I think grinding your own chisels definately has it's advantages (I have two home made bowl scrapers that work great) but working out how to do it in a cost effective way is the trick.
Cheers
Paul

Cliff Rogers
22nd Nov 2004, 08:22 PM
... recently acquired ... stock ... utilized ...at ... Oak Ridge nuclear weapons plants, ...

Cool, does it glow in the dark? :D

MathewA
23rd Nov 2004, 12:34 PM
I agree with you to a certain extent. In the hardening process of tool steel, which includes O1, A2, D2, M2... you never quench any of them in water. It's far too harsh a coolant. The steel is heated to over 1500 degree F for O1 and higher for the rest. Dipping the steel in water at that temp would destroy it. O1 is quenched in oil. All tool steel from A2 on up needs to be air quenched, or you risk fracture. After that though, you should never reach a temp that should risk fracture by cooling in water. If you have you are doing something very wrong. So yes you can cool a hardened and tempered back tool steel blade in water. If for some reason the tool did fracture or... after diping water then the tool was already faulty, which isn't all that uncommon. I've seen Crown gouges continually chip at the edge because of faulty manufacturing. Just a side note, O1 and A2 are not high speed steel. O1 will de-temper around 400 degrees or more, A2 at around 600 degrees (blue) or more. I'm not sure about D2, I think it is. M2 on up is. They start loosing their hardness at over 1000 degrees, or when the viagra runs out:rolleyes:.


Never, Ever Not no How dip HSS tools in water. It can fracture them.

If they get hot let them cool on their own.

IanA
24th Nov 2004, 10:00 AM
Has anyone had experience with making a ring tool by grinding an edge on a discarded bearing race. (With balls or rollers first removed, of course.) The cutter is then welded to a bar stock.

I've heard of this being done, but the info has not come from a source with any direct experience.

Is the steel of a bearing race uniform throughout or is it case hardened?

PAH1
24th Nov 2004, 11:13 AM
IanA

As I understand it most bearings are case hardened, many state it in the specs for the bearings.

Grizz
27th Nov 2004, 07:00 PM
I was interested to read the comments about quenching HSS tools. Everything said was pretty comprehensive, but, I believe, somewhat impractical. In my days as an apprentice Fitter and Turner, I was instructed to quench HSS tools regularly when grinding. This usually meant that when heat could be fealt in the body of the tool, it was quenched. These were mostly 1/4" - 1/2" square section tools up to 3" in lenght so it didn't take much for the heat to get through. It was also common practice (at least where I did my time) for tradesman to encourage apprentices to overheat lathe tools to see what the effect was. This regularly resulted in tools that blunted quickly and cut poorly. However, these tools could be refurbished by grinding away the "blued" area. IMHO, it is best to ensure that you do not overheat any tool and that you quench regularly. This also gives you more time to correct inaccuracies as you can check the outcome of your grinding more regularly. Anywho, that's my opinion.

Griz.

Darrell Feltmate
10th Jan 2005, 10:20 AM
Just for the sake of interest I would like to throw in my 2 cents worth, that is 2 cents Canadian, not sure what that works out to Australian? Anyway, I use mostly home made tools for turning, certainly for face plate work. Instead of a gouge, consider making an Oland tool

http://aroundthewoods.com/oland.shtml

It is quick to make in the home shop, works beautifully, and you can make a new tip for a dollar or two.

Darrell

Cliff Rogers
10th Jan 2005, 01:41 PM
.... that is 2 cents Canadian, not sure what that works out to Australian?....
About 1.7934 cents AUD as at 10/1/5 :D

rsser
10th Jan 2005, 03:30 PM
Thanks Darrell. Thought so.

Down here in Victoria (Aus that is) there's a club that makes them for sale - Eltham or Peninsula turners, can't remember which. (They also do a nifty Firmager style parting tool).

BTW I found your website piece on turning a crotch v. useful. Have several large 3 way crotches of Silver Birch and your piece gave me some new ways of thinking about how to approach them.

smidsy
10th Jan 2005, 09:13 PM
Darrel,
I think people here in Australia have bit of an aversion to home made tools - at least the people I've met do.
I have two scrapers that were cheaply made with tool steel blanks from a local shop, they are the best scrapers I have yet people at my club look down at them.
That Oland tool of yours looks like a nice bit of kit, so I think that will be my next task in terms of tool making.
Cheers
Paul

RETIRED
10th Jan 2005, 09:37 PM
I don't think that people have an aversion to making their own chisels. Most people can't be bothered when you can buy them at a reasonable price versus a lifetime use.

I make my own skews and scrapers but I don't have the time to produce IMHO a second rate deep fluted bowl turning gouge when I can buy one that is dead right.

But then it ain't a hobby with me either.

Cliff Rogers
10th Jan 2005, 10:44 PM
....But then it ain't a hobby with me either.'s'right, I fix computers & I could make them too, but I don't 'cos I can buy them ready made with a 3 year warranty for less than I can make them myself.

Now a-days, I tend to buy good HSS tools without a handle & modify/grind them to suit what I need/like.

I always have an eye out for a bargain & the best one yet was an unhandled Sorby 1" skew for $10 at a clearance sale. I already have 3 skews & I HATE all of them so I had no problems grinding it into a curved scraper with a long left side & a slope on the front. (Like those new ones but mine leans to the left for shear scraping)

For anyone that knows & loves the Superflute Bowl Gouge, crown have a deep flute bowl gouge with an extra long flute (goes further up the handle) & it is almost the exact same profile as the superflute. I got 2 of them without handles for about $80AUD each.

Darrell Feltmate
10th Jan 2005, 10:51 PM
Cliff
I hear you on the computers. I made my first with a soldering iron in the basement (never mind how long ago that was) but now it is a card flipping exercise for repairs. However, I wanted a set of hollowers with arm brace and was looking at a couple of hundred easy. A half hour's work and I had a 45* and a straight tool, each with an arm brace and all for a cost of about $20. I have not made $180. an hour in my life. Nice tools too.

___
Turn safe
Darrell

Cliff Rogers
10th Jan 2005, 11:19 PM
MMmmmm, yeah but... not all computer fix'n, woodborers have access to steel working facilities. I made my own 'first' hollowing tools, even won a couple of prizes at the Townsville show(s) with the resulting hollow forms.

Then I bought a REAL hollowing tool & I haven't used the home made ones for years now. I haven't chucked them out 'cos I made them (out of computer parts) but I don't use them any more.

powderpost
10th Jan 2005, 11:34 PM
I make special purpose scraping tools from mild steel blanks varying from 12mm x 12mm to 35 x 12, with pieces of heavy duty hss machine hack saw blades. Better than shaping a bought hss blade for a special job. The hack saw blade is silver soldered to the mild steel. Some of these "special job" tools sometimes even get to have a handle. For "round the corner" jobs I have bent 12mm and 19mm round mild steel rods shaped along the lines of a question mark ( ? ) again with a piece of hss hack saw blades silver soldered on. I also have made a small detail gouge from a car tappet push rod, marginally successful. As well as that I have used a 4lb axe, tomahawk and a welders chipping hammer to replace a skew, a very interesting exercise. Why bother??? because I like to push the boundaries.
Jim

SWR
11th Jan 2005, 06:49 AM
Just for the sake of interest I would like to throw in my 2 cents worth, that is 2 cents Canadian, not sure what that works out to Australian? Anyway, I use mostly home made tools for turning, certainly for face plate work. Instead of a gouge, consider making an Oland tool

http://aroundthewoods.com/oland.shtml

It is quick to make in the home shop, works beautifully, and you can make a new tip for a dollar or two.

Darrell
Darrell,

Couldn't agree with you more...I made an Oland tool based on plans from your web site and it works so well..

I found a place in Sydney that sells the metal lathe tool steel in three-eighth inch width for abour $9 a piece.

I get a lot more satisfaction turning with home made tools and tools that I have recycled (like really old chisels and the like). I have also had some success using D-2 tool steel that is quite cheap if you shop around.

I know that some people don't have any interest in making their own tools but I like to try and be self sufficient and it doesn't take a lot of effort.

I guess it is the Scottish in me that makes me try and do the cheap ass option...I just can't spend money on something I can do for a hell of a lot cheaper. My whole woodworking hobby has been founded in doing it on the cheap and recycling things I have found to make them do something that it was never intended to do.

For what it's worth...


Cheers,


Scott in Peakhurst.


Ah, the wisdom of Homer...

"You couldn't fool your mother on the foolingest day of your life if
you had an electrified fooling machine."

Darrell Feltmate
12th Jan 2005, 10:37 AM
Scott

Glad the Oland tool worked out so well for you. I do not know what shipping from Enco costs but the last 3/8" cutting bits I got from them cost me about $2.00 each. www.use-enco.com (http://www.use-enco.com) If you are looking at a hollowing tool I just put up a page on the web site with one using an articulating head. I have a couple of improvements to post but the ideas are there. I just wanted to get an idea of time involved for tool making by people in a home shop who do not have special metal working tools available. I used an angle grinder although a hack saw and bench grinder could have been used instead, a vise, a drill press and a tap. Nothing special but I got an articulating tip hollower for about $4.00 and an hour's work.

_________
Darrell
www.aroundthewoods.com (http://www.aroundthewoods.com)