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VikingCode
31st October 2014, 07:02 AM
I'm toying with the idea of making my own carbide-cutter chisels, as I simply can't afford the EWT chisels. We have two of the smallest size ones, and the wife loves them especially for roughing as she finds it less fatiguing.

I'm not really familiar with metal properties, and I'm having a hard time figuring out what the best - and safest - choice is for this job. Some people I've seen use tubing, while others warn against using mild steel as it is "prone to stress fractures". The local metal merchant (3140) told me the closest place to get tool steel is over in Dandenong which is a long walk as I don't drive. Trying to find 10-12mm x ~500mm o1 square bar online is... vexing at best.

Has anybody made their own? Whats the generally recommended best choice of steel?

chuck1
31st October 2014, 08:12 AM
Someone may correct me, I was thinking of using some bright bar and buying the cuttertips then all I have to do is make a handle and get the tip tapped and a screw to hold the Tip.

Oldgreybeard
31st October 2014, 08:56 AM
The local metal merchant (3140) told me the closest place to get tool steel is over in Dandenong which is a long walk as I don't drive. Trying to find 10-12mm x ~500mm o1 square bar online is... vexing at best.



Did your local merchant give any more detail other than "tool steel"?

I will be talking to a toolmaker / engineer friend later today as I am looking at the potential to make my own gouges using the Woodcut gouge tips. I will keep you informed of the outcome of the discussion. If you can give me any further information from your merchant, that may help.

Bob

VikingCode
31st October 2014, 09:16 AM
Did your local merchant give any more detail other than "tool steel"?

As I said I'm not a metal guy, so some of this info might be wrong. Tool steels tend to be higher carbon/alloy steels, with various grades for various purposes.

O1/A2 are often used in newer/fancier bench chisels and planes because of their work ability, yet still maintain an edge for awhile. HSS is (I think?) generally M2 grade. For turning chisels that don't actually do the cutting, the "S" series of grades (ideally S7?) might be best as they're designed for shock resistance.

From what I can tell, Bohler Uddeholm in Dandenong seem to have the (victorian) market just about sewn up!


Someone may correct me, I was thinking of using some bright bar and buying the cuttertips then all I have to do is make a handle and get the tip tapped and a screw to hold the Tip.
Yup, thats the process, just concerned that mild steel wouldn't be suffice. Perhaps I'm just being overly cautious.

Sawdust Maker
31st October 2014, 09:34 AM
you could get a length of stainless rod/bar about 1/2" square

I doubt you'd need tool steel for the shaft
my understanding is that tool steel is for making the tools eg the scraper etc something you'd put an edge on

Drillit
31st October 2014, 09:42 AM
If you go to McJing's website you will see that they sell steel for tool making. I have from time to time bought some
at the WWW shows and found it satisfactory and relatively cheap. They will of course freight to you. Worth a look?
Drillit.

Paul39
31st October 2014, 09:49 AM
I have salvaged round steel rods from Xerox machines and printers. Grinding a flat on the end and having a saw sharpening shop braze a tip like one of these http://www.alibaba.com/product-detail/Carbide-wood-turning-tools-_2001827655.html?s=p on the end would make a tool that the shop could shape to your taste. You would then just keep it sharp by using a diamond card sharpener on the top.

I take my round EWT easy finisher bit off and lay it on a diamond card with a little water, scoot it round and round for a minute and re mount. I've been using the original one for a couple of years. I use it for roughing. For finishing I use freshly sharpened HSS or carbon tools.

If I were to make a tool to use the EWT round bits, I would use a 12 or 16 mm round bar so it could be rolled over easily for shear scraping.

Mild steel would be more inclined to bend than break.

Socket extensions are another source of tough steel:

http://www.harborfreight.com/pc-super-long-extension-set-67975.html

Wonder through hardware or engineers shops and look and ask.

Any of these close?

http://www.steelsolutions.com.au/steel-square-black-c-105.html

http://www.steelsolutions.com.au/steel-round-black-c-104.html

Oldgreybeard
31st October 2014, 09:50 AM
Ok, I have the information we need.

Supplier is Bohler in Dandenong South.
Material is 4140 High Tensile Ground Bar and comes in a 6m lenght and can be drilled, tapped or welded - but if welded would have to be rehardened afterwards. Price for a 6m length is $40.00 incl GST.

Bad news is that it is available in 12.7mm round bar but not square. Smallest square section is 20mm. They would cut to size eg. 12 x 12 ex a 12mm thick plate, but that would not be a ground finish and obviously quite a bit dearer. I have not checked other suppliers for square section yet.

12.7mm round bar cut to length (say 400mm long) should work out to less than $5.00 per lenght (incl GST).

If there is enough interest, I would buy a length and cut to size.

Bob

Oldgreybeard
31st October 2014, 10:56 AM
Following on from my earlier post, I questioned my engineer friend about other options such as stainless steel. His response was that it may be OK, but the high tensile 4140 steel is recommended for its strenght in resisting the rotational forces that would be applied to the tool and the fact that these are often in more than one plane eg. lenghtwise from the contact of the tip and rotation through contact of the side of the tool.

He suggested 4140 as the safer option.

Bob

VikingCode
31st October 2014, 11:27 AM
If you go to McJing's website you will see that they sell steel for tool making. I have from time to time bought some
at the WWW shows and found it satisfactory and relatively cheap. They will of course freight to you. Worth a look?
Drillit.
Argh, I was there on Friday and didn't even think to look for it. In my defense I was pretty worn out by the time we got to McJings stall.


Ok, I have the information we need.

Supplier is Bohler in Dandenong South.
Material is 4140 High Tensile Ground Bar and comes in a 6m lenght and can be drilled, tapped or welded - but if welded would have to be rehardened afterwards. Price for a 6m length is $40.00 incl GST.

Bad news is that it is available in 12.7mm round bar but not square. Smallest square section is 20mm. They would cut to size eg. 12 x 12 ex a 12mm thick plate, but that would not be a ground finish and obviously quite a bit dearer. I have not checked other suppliers for square section yet.

12.7mm round bar cut to length (say 400mm long) should work out to less than $5.00 per lenght (incl GST).

If there is enough interest, I would buy a length and cut to size.

Bob
400mm might actually be the ideal length too - the EWT full size tools are 12mm x 215mm (1/2" x 8.5"), which allows (if going for a carbon copy) 185mm inside the handle for a good grip. Only a couple of their hollowers and the parting tool are any longer.

On the subject of round vs square, square would be "safer" as its easier to keep flat/straight, particularly when hollowing out a bowl. However, I don't know if thats going to be any less safe than a regular bowl gouge with round bar. And its not like there aren't commercial carbide tools with round bars (Sorby TurnMaster, various deep hollowing tools, etc)

I'd be down for a few lengths - that way the wife can have a few shapes at her disposal.


He suggested 4140 as the safer option.
That makes me feel a bit less pedantic! :D

NeilS
31st October 2014, 02:38 PM
you could get a length of stainless rod/bar about 1/2" square

I doubt you'd need tool steel for the shaft
my understanding is that tool steel is for making the tools eg the scraper etc something you'd put an edge on

+1

I have founds stainless steel has been fine for the purpose. I have given mine a good workout at times and it has been fine.



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The tensile strength of mild steel is 370MPa (yield) to 440MPa (ultimate), which might be a bit too soft
316 stainless is between about 500 to 680MPa and
304 stainless up to 720MPa, which I have found robust enough with 12mm square rod.
A high tensile steels should take you above 700MPa, as long as you don't de-temper it with heat.


It is probably a case of what is readily available to you at a reasonable cost.

Sawdust Maker
31st October 2014, 03:03 PM
from the EWT site

"The Easy Rougher tool bars are CNC machined from solid stainless steel bar stock."

NeilS
31st October 2014, 03:21 PM
I have founds stainless steel has been fine for the purpose. I have given mine a good workout at times and it has been fine.




This is what I mean by 'a good workout'... it's the root ball of an apple tree that I turned the other day. For size comparison, it is hanging off a 5" chuck. The 12mm sq shaft had no problems with roughing that down. Can't say the same for the TC tip that had to deal with all the dirt and stone inclusions...:rolleyes:




329748

Oldgreybeard
31st October 2014, 04:17 PM
Neil's photo proves the point that 12mm sq Stainless can do the job.

However, my requirement is for 12.7mm round and I have now received confirmation of the price of $75 incl GST for a 6m length of 4140 High Tensile rod picked up from Dandenong, cut to size (400 mm) and delivered to my home - ie. $5.00 per peice. I will place an order next week and should have delivery in about a week.

The 6m lenght is about twice my immediate requirement, so am happy to share. Price $5 per 400mm lenght pick up in Mt Waverley 3149. There will only be 9 pieces available - first in first served. Unfortunately, I am unable to supply the 12mm sq SS bar.

Bob

hughie
31st October 2014, 08:22 PM
I tend to make most of my own hollowing tools. 4140 will do for a bar but as you have found its only sold in round, theres also 1045 which is fairly stiff. if you go towards Stainless you should be looking for 316 grade as its about the stiffest and it can be available in a square. But generally only from a specialist steel supplier who specializes in stainless.

If you consider m2 or m24 etc these are HSS steels and wont be cheap and the hardening is generally beyond the back yard heatreater as the initial temp is around 1300c+ and it requires triple tempering and just to make more interesting the heat treatment numbers need to be accurate.


What you need is a simple source of already hardened HSS of which you can insert into your hollowing bar as it can be ground with conventional grinding wheels.

Sources such as, broken HSS drills make an excellent resource for this. If your still keen to use TCT tungsten carbide tips. Then seek out a local engineering shop that has a few lathes as they most certainly use TCT cutter for turning steel and as they wear out or get chipped they generally throw them away.Look for the ones with a hole in the centre as they are the easiest to mount on a hollowing bar.

I would avoid going to Bohlers as they tend to be the dearest steel merchants around, do a Google search of your local area or city, in Sydney we have Edcon Steel as one of the cheapest and they will sell by the metre. I generally buy a couple of metres at a time of 4140

McJings sell HSS stock in various sizes and configurations, but the quality tends to vary. They also have silver steel as reasonable prices and this can be hardened with a blow torch and water as a cooling medium.

steamingbill
31st October 2014, 08:44 PM
There is a book called "The Frugal Woodturner" by Ernie Conover that you would find available in your local library system via an interlibrary loan.

He discusses ways of making your own tools its quite interesting.

Bill

Treecycle
31st October 2014, 10:29 PM
No idea where you are Viking code, but you also have Steelmark Eagle & Globe in Westall 95492666. It looks like you can get yourself some lengths from oldgreybeard now anyhow.
Attaching your cutting tip using a screw would be the best way as you can then easily rotate it when blunt or replace it. This way, no heat is involved that would change the tensile strength.
The main problem with mild steel is that it will vibrate due to its lack of tensile strength. I guess this could lead to fatigue failure over a long period of time, if you persisted with it that long.

Michael Brazeau
1st November 2014, 12:14 AM
I made a couple of the larger carbide cutters last year using 1/2" square bar I found at the local hardware store (not stainless steel just regular cold rolled steel). It's plenty strong enough for turning and easy to work with (grinding the end and tapping some threads for the cutter). Made the handles from some hard maple and they are really solid. I can post pictures later if you are interested.

hughie
1st November 2014, 10:26 AM
If you do a search I have several articles on making your own hollowing tools. Plus one on a brief description of the type of tungsten carbide tips that are generally around.

With the recent new format for the forum, I 'm hopeless at finding anything.

hughie
1st November 2014, 10:33 AM
Neil's photo proves the point that 12mm sq Stainless can do the job.
Bob
It kinda depends on the over hang, I tend to go up a size 13mm or 14,16 if its available.

But if look around for old linear bearing shafts they are either flame or induction hardened. Then ground and some are hard chromed to boot. These make excellent hollowing bars, the hardness is not a problem as you can localize the hardness by applying heat to area you want to cut or drill. Generally if you get it to a deep blue your on your way if not then cherry red and let it cool down.

NeilS
1st November 2014, 01:44 PM
It kinda depends on the over hang, I tend to go up a size 13mm or 14,16 if its available.




I defer to Hughie on all such matters.

hughie
1st November 2014, 04:54 PM
I defer to Hughie on all such matters.

My friend you are most kind. :2tsup:

Paul39
3rd November 2014, 10:52 AM
The Frugal Woodturner is still being sold:

http://www.amazon.com/dp/1565234340/?tag=googhydr-20&hvadid=48009071505&hvpos=1t1&hvexid=&hvnetw=g&hvrand=13544028563691618383&hvpone=&hvptwo=&hvqmt=b&hvdev=c&ref=pd_sl_6ayztyski7_b

I looked up the safety of the ebookee site, read comments below and make your own choice:

https://www.mywot.com/en/scorecard/ebookee.org#page-1

I think it is better to get the book from the library or buy a new or used copy.

Ernie is still teaching: http://www.conoverworkshops.com/wwprivate.shtml

Those of us who are trying to make our fortune turning, need all the help we can get. :D:D:D

BUY THE BOOK!!

Hermit
8th November 2014, 03:06 PM
For cutters, rather than buying original 'Easy' or 'Sorby' etc, this guys prices are hard to beat:
http://azcarbide.com/

To use them on a Sorby Turnmaster, the tool head needs to be modified slightly, but they fit the other brands without mods. I have a round one on an Easy Finisher, and it cuts as well as the original cutter.
A touch-up with a diamond hone after each use is well worthwhile, too, regardless of brand. Makes a huge difference. A properly sharpened cutter leaves a surprisingly clean surface.



And its not like there aren't commercial carbide tools with round bars (Sorby TurnMaster .....)

The Turnmaster is a 3/4" round rod, but it's machined flat on the bottom along the section that contacts the toolrest.
(The head unscrews and is indexed to tilt 45 degrees in either direction for shear scraping.)

Personally, I'd much prefer flat-bottomed shafts. One less thing to keep an eye on. :wink:

penguin
8th November 2014, 05:04 PM
you can also buy stainless steel for make a keyway form bolt suppliers in either metric or imperial in all different sizes and is in 300mm lengths

regards
penguin

powderpost
9th November 2014, 10:44 PM
Some people I've seen use tubing, while others warn against using mild steel as it is "prone to stress fractures".

For what it is worth, I have made numerous turning tools, mostly scraper type, from mild steel. These have had pieces of machine hack saw blade silver soldered to the top for the cutting edge. The size of the mild steel varied from 35mm x 10mm to 12mm x 12mm. I have not had any evidence if fatigue or fracturing over a period of 20 years.

Jim

VikingCode
11th November 2014, 07:18 AM
Hi guys, illness in the family has prevented me from pursuing this further in the last week. Yay chemo and such. And then unrelated, I lost my voice a bit over a week ago and it still hasn't returned in force so it sounds like I'm gargling marbles when I'm on the phone! If only the suppliers I'd found could answer emails :(



This is what I mean by 'a good workout'... it's the root ball of an apple tree that I turned the other day. For size comparison, it is hanging off a 5" chuck. The 12mm sq shaft had no problems with roughing that down. Can't say the same for the TC tip that had to deal with all the dirt and stone inclusions...
:rolleyes:

Yeah, okay, I guess that'd be ok :p Thats bigger than anything we've tackled so far, so I think that'd "just" do the trick.


I would avoid going to Bohlers as they tend to be the dearest steel merchants around, do a Google search of your local area or city, in Sydney we have Edcon Steel as one of the cheapest and they will sell by the metre. I generally buy a couple of metres at a time of 4140
There are a couple in the local area that have mild steel, one that has stainless, but the vast majority are all in Dandenong/right near Bohlers (which is too far for me to get to). Argh!

(and from here is where I start complaining about the weird quote features that won't actually generate the 'quote' for the posts I want until I submit this reply)

I'll see if I can find a copy of the book Hughie/Paul39, it looks like a good one to have around.

@Hermit, AZCarbide looks good - much cheaper than EWT cutters locally, and in all the shapes. I've seen a few people order from Carbide Depot (http://www.carbidedepot.com/detail.aspx?ID=151059), but AZCarbide prices are a bit better and come with the screw. Global Tooling (http://globaltooling.bizhosting.com/products/carbide-insert-knives.html) is cheaper again (for square), but no detailer/diamond shape - not sure if the geometry is any different on the rest though.

I've found Williamstown Metal (http://www.metalstore.com.au) also have an ebay store (http://stores.ebay.com.au/williamstownmetals?_trksid=p2047675.l2563) which *gasp* lets me see prices on the internet. And (decent) delivery rates. Who would have thought that could be a thing in this day and age!? While they're stainless length is 300mm, I'll shoot through an email to see if they've got anything longer (and 316).

Oldgreybeard
11th November 2014, 08:33 AM
I've found Williamstown Metal (http://www.metalstore.com.au) also have an ebay store (http://stores.ebay.com.au/williamstownmetals?_trksid=p2047675.l2563) which *gasp* lets me see prices on the internet. And (decent) delivery rates. Who would have thought that could be a thing in this day and age!? While they're stainless length is 300mm, I'll shoot through an email to see if they've got anything longer (and 316).

I received the 4140 x 400mm lenghts yesterday thru Bolhers via Springvale Steel - steel, cutting and pickup of 6m lenght from Bohler in Dandenong ended up at $3.00 (incl GST) per lenght. (I had been a customer of Springvale Steel spending in excess of $10,000 per month when I had my business in Springvale and still receive "mates rates" for my occassional purchases)

There are 8 lenghts available at $3.00 ea pick up Mt Waverley 3149. PM with postcode for delivery cost.

Bob