Woodcut negative rake scraper ... as a lacer skew

[QuarkVI]

Hi,

for those of you who own or have seen a woodcut negative rake scraper in person .... am I seeing things or is this essentially a skew with an Alan Lacer grind?
reason I ask is I was looking at purchasing the bigger Lacer style skew from D-Way in the states (can't find a big piece of hss to grind my own) and just happened to see the woodcut scraper while perusing their gouges when a lightbulb went off.

Will work out a whole lot cheaper and is local so seems to be a winner.... unless I am missing something... just needs the one side softened so it rolls on the tool rest.

Busy going down a skew rabbit hole and next thing to try is a lacer grind and want a big skew for bigger spindles and roughing. So far I don't care for oval skews and a couple of smaller round skews I made over Christmas are handling quite nice. Also been playing with a bedan for a few months (diy out of 12mm square hss) and can't see an advantage over a skew but absolutely hate the way the corners dig into the tool rest so it has been relegated to a parting tool.

Happy New Year to all.

cheers
Robin

[Mobyturns]

Call it what you will - Alan Lacer skew - negative rake scraper - Glenn Lucas french curve negative rake scraper - They all have the same basic design as a tanged flat bar ground to your preferred shape. The only differences between the neg rake scrapers and skews will be in the stock bar size;, wheter they have rolled/radiused edges or not; and the grind angles.

There is such a wide range of skew angle preferences that I guess the Woodcut neg rake scraper probably would cut as a skew though you may wish to play with the grind angles.

[hughie]

The simplest way to get a negative angle scraper is to simply lift the handle on your current scraper to a negative angle. The benefits in this are you dont need to buy one and your scraper is both positive and negative.
Does it work? yes. I have been using mine this way when ever the need arises.

[Sawdust Maker]

Would a 30 mm P&N skew suit?
Available from Vermec in Brisbane or Jim [CWS] down Geelong way

PS and I've converted a scraper to a skew

[Woodturnerjosh]

The simplest way to get a negative angle scraper is to simply lift the handle on your current scraper to a negative angle. The benefits in this are you dont need to buy one and your scraper is both positive and negative.
Does it work? yes. I have been using mine this way when ever the need arises.

I still found my regular scrapers to grab when used like this, they also left an inferior surface on burls compared to a scraper sharpened as a negative rake. So I'm wondering what angle you have your regular scrapers sharpened to? Mine were always around 70 degrees and I think I use around 50 on the negative rake. (they are useless in softwoods though)

[Mobyturns]

Guys I think its the other way round - repurpose a Woodcut a neg rake scraper as a skew chisel.

[brendan stemp]

Robin, I would suggest you contact Woodcut and ask them for one of their NR scrapers without the grind; ie just get the steel and shape it yourself. You will save some steel this way because the NRS's grind is not quite what you want for a skew.
The background to the NR scraper is that it was a name given to a skew chisel to plicate the traditionalists who hated seeing the skew used as a scraper. The main difference will be that the Woodcut NRS will be thicker steel than a skew with the same width. But essentially the Wodcut style of NR scraper is a derivative of a skew chisel.

[rsser]

You can get M2 blanks from McJing. For this maybe the 8x30x200 but there are other sizes. https://mcjing.com.au/categorybrowser.aspx?categoryid=647

I fabbed an undercutting sidescraper out of one. Did rough shaping by cutting with a 1mm x 100mm angle grinder wheel (aka Inox). Took a while.

[rsser]

Gary Pye sells a big round-nose scraper that might prove a better option to mod.

So with a - ve rake on the top are you sposed to rub the bevel?

[powderpost]

I am fascinated by this type of discussion. I am a traditionalist and generally use turning tools in what is accepted as the "traditional" method. There is two very important issues missing from this discussion. The first is the skill level and understanding, of the operator, and I add quickly, I am not denigrating any body. The second issue is that we are using a VERY variable material, requiring variable solutions

A traditional skew can be successfully on wood in a scraping mode. However the variables in wood play a part. The edge on a standard skew used as a scraping tool will work well and will last longer on softer timbers but perform abysmally on the harder species. The solution is to increase the sharpening angle to produce a stronger edge, which creates a negative rake tool. It is essential the the cut be on or below centre and the handle held up. I have done this for a long time even before the advent of the negative rake syndrome appeared, even on burl material. In my opinion, shear scraping is a better option.

If all else fails to produce an acceptable finish on wood, then do what ever it requires to get the job done. I can't see any of the older professional wood turners resorting to using a negative rake tool.

Jim

[Woodturnerjosh]

Unless I'm being misled by the article on negative rake scrapers that Stuart Batty wrote, but haven't they been used by instrument makers on ivory and blackwood for over a century?
Yes, I realise this is way off the original topic :)

Josh

[rsser]

One of the things that used to be done by some turners was to burnish a hook & then rub the bevel. Lee describes it in his book on sharpening. The hook does the cutting.

It takes more control than conventional scraping so I didn't persist with it.

This presentation though is still practiced by some Oland tool users.

[Paul39]

I just looked at a photo of an Alan Lacer skew. I would take a skew you have or one you buy and grind the curve on it.

I accidentally made an AL skew by using the toe of one of my Chinese junk skew that I used to round over the ends of my tool handles. As I was working down to the drive or tail center I did not want to risk hitting either with my "good" skew. I was using the toe a lot and resharpening, so eventually I had a curved skew. I liked the result so much I did the same with my Thompson.

A skew can be used as a negative rake scraper but I think the edge would be worn off much quicker than a scraper with some steel under the edge. Skews are generally thinner than scrapers so would be more likely to vibrate and give a rough surface.

My favorite scraper is an unhandled knife from a 12 inch jointer - planer. It is over 12 inches long, 2 1/2 inches wide, and almost 1/2 inch thick. I ground the sharp cutting edge off and put a gentle curve on the end. The only reason I would use a scraper with a ground negative rake would be on the inside of boxes or vessels where you could not tilt down a regular scraper to the negative rake position.

[Woodturnerjosh]

367419 As I couldn't find it available online anymore... here is Stuart Batty's article on negative rake scrapers covering where they are best used, sharpening angles and advantages/disadvantages when compared with regular scrapers. I've only been turning for a decade and I find they achieve a much better surface on eucalyptus burls than regular or shear scraping or even a gouge (as supported by the article written by a traditionally trained production turner)

[rsser]

Thanks WJ. An interesting read.
So the raked top essentially pitches the burr forward. This would put it right in the firing line.
Funny that a time-served turner doesn't know about turning a hook; though he does mention a 'burnished burr'. Maybe it's a US thing. It makes for a stronger and cleaner cutting edge.

[Paul39]

I agree with Stewart Batty's article. I did not say in my post above that I only use scrapers in the negative rake position. I make mostly bowls so there is plenty of room to have the tool rest high and point the heavy scraper down.

I have a 1725 RPM grinder at the end of my lathe with an 8 inch100 grit white wheel on the platform side and an 8 inch 200 grit white wheel on the bowl gouge jig side.

When I come into the shop I turn on the lights and the grinder. I grind the scrapers with a quick swipe upside down on the platform, use it until the burr is gone 15 - 30 seconds, quick swipe on the grinder, repeat.

On hard timber, hard maple, oak, cherry, walnut, I get about a 220 grit sanded surface from the scraper. I have not gotten any burls yet.

I grind my Bedan looking mystery metal tool the same way for gouging off bark, dirt, etc. before using a bowl gouge.

I have been turning 7 years and only last week started making deep hollow vessels. I expect to be making a negative rake scraper or two for cleaning up the insides. I hollowed with an EZ Finisher and the surface looks as though I used a chain saw. Two Norway Spruce from a Christmas tree and one Red Oak.

[QuarkVI]

as a FYI

Following on from Brendan's suggestion I contacted Woodcut as to whether they provided the scraper unground - unfortunately they do not.

cheers
Robin