Bowl Gouges

[big chief]

Hi everyone

Can someone tell me what bowl gouge is best/easiest to use for pulling cuts?

I have seen different types like fingernail, long and strong, and superflute. What are the differences or advantages of each type?

Thanks

 

[TEP]

Hi chief.

Anything from a 3/8" gouge upwards, with long grind wings. There appear to be two prominent forms of groove a 'V' or a 'U' shape. I don't know if one is better than the other, my preference is for the 'U' forms.

As with most in woodturning we all have our personal shapes and likes. Just try a long grind on a gouge and see how it goes. Then you can adjust it to suit yourself. The 'long & strong' I wouldn't worry about too much, they are just a bit longer and heftier than a normal gouge. Stick with the standard tools until you get used to them.

 

[robo hippy]

Any bowl gouge will work. Spindle gouges tend to be not as sturdy, and a spindle roughing gouge is for spindles. How much you can take off in a pass depends on how far back the edges are swept, and how much horse power/torque your lathe has. I actually prefer a heavy scraper for roughing, and the gouge for finish cuts, though a shear scraper works fine as well.
robo hippy

 

[big chief]

Thanks for the replies

Had a go at my first bowl this morning. Got the outside finished great. Then when I started on the inside the bowl came flying off the chuck and marked the outside! I was fuming!

Ah well, practice makes perfect......

 

[loz]

Hi Chief !

Here a link to a great online video for anyone starting with bowls./

http://www.woodworkingonline.com/2006/1 ... r-an-hour/

 

[Vulthoom]

Right at the end the presenter puts a handplane on the shelf behind
him flat down on the blade....

Tut, tut, tut......

And is it just me that goes cold all over when they watch someone using a bandsaw...... 8-[

 

[big chief]

Hi Chief !

Here a link to a great online video for anyone starting with bowls./

http://www.woodworkingonline.com/2006/1 ... r-an-hour/

Thats a great video. But how do they make it look so easy!!!

On a side note to this thread, what is the best way to deal with end grain? I found it very hard to get turned smoothly. Is there a better way to turn this?

 

[robo hippy]

Well, that video was different, and like an old saying goes, "All of God's children are different, and some of us are more different than others." I do a lot of things differently than he does. I would suggest getting several videos to watch by different turners and watch them, then experiment to see what works best for you. There are a lot of them on You Tube.

As far as the catch on the inside of the bowl, I would guess that it was with your gouge. There are 2 main causes for this catch, and we have all done it. Most of the time, it is because the flutes of the gouge are too straight up, rather than rotated slightly away from the cut. The inside edge will rotate into the wood and you have a catch. The other reason is that if you are roughing (taking a bunch of wood in one pass), you need to rotate the gouge almost 90 degrees to the side, as in pointing to 3 o'clock. If you have the flutes more up, and get then entire nose burried in the cut, it gets very grabby. Too much steel in the cut at one time. If you have variable speed, down to 50 rpm or less, you can play around with this to see what happens, and where you get the catch. You have already done this at higher speeds. You can get the same catches when doing the outside of the bowl, but they are more common on the inside of the bowl.

robo hippy

 

[big chief]

Thanks Robo Hippy.

Really appreciate you taking the time to give such an in depth reply.

Its great to get so many different opinions on things and to try them to see what works best for me.

 

[Bob Chapman]

I agree with Robo Hippy - we must do things differently from the guy in the video. There are a few things I disagree with the video about, but just to mention two:

The size of the spigot (tenon) to hold the bowl in the chuck is determined by the size of the chuck. The size of the foot of a bowl is, or at least, should be, determined by the size of the bowl. There will be very few instances where the two are identical. In general making the spigot double as the foot of the bowl is a mistake in design terms.

Secondly, hollowing a bowl from centre outwards means that by the time you get down to the required wall thickness there is little strength left in the walls to support them during the final cuts (unless you leave them very thick). Hollow from the outside towards the centre, leaving as much wood as possible in the centre for as long as possible to support the bowl.

Having said that, it's your bowl - so you can do what you like!

Bob

 

[big chief]

Cheers Bob, some helpful tips there.

Can you give me any advice on working the end grain? I find I am having a bit of difficulty doing this.

What is the best tool to use for the end grain?

Thanks again

 

[CHJ]

big chief, in your opening post you refer to a gouge to do a pulling cut, in my limited experience attempting a pulling cut on the inside of a bowl is not one I would recommend until well versed in the mechanics of the forces involved.

For starters there is a a real risk that there will be less bevel in contact with the wood when pulling as opposed to pushing, any slight mis-alignment or as robo says too steep a bevel grind can rapidly result in a catch as the cutting edge dives in and rotates the gouge in your hand.

As far as end grain tear out is concerned, keep gouges as sharp as possible, even re-sharpening immediately before the final couple of fine cuts.

Try wetting the wood with water or finishing oil to swell the fibres and lubricate the cutting edge. If the wood is very fibrous or soft try firming up with sanding sealer or even thin CA glue if the area is small before final finishing.

Be prepared to do hand sanding with the lathe stationary for difficult grain bits, this can often take considerably longer than the rest of the turning

Bob's point about retaining strength in the outer edge as long as possible is very valid, and to expand on the point try not to leave a bowl unfinished on the lathe for any length of time as there is a real risk of the periphery distorting whilst it is resting, making it very difficult to finish turn.

 

[hpl]

Hi Big Chief

Just been reading the post and thought I'd add my thoughts.

The video on the link is very good IMO and very similar to how I turn.

On the end grain, a gouge is usually the best tool to cut with. Taking several very light cuts with a very sharp gouge is usually the answer. If you note on the video on the link, while Brain is turning the outside he talks about keeping the handle low and taking shearing cuts. You will need to experiment with this to find how it works for you, the angles you need etc. (I could show you but not so good at describing it, watch the video closely) but in many timbers this will give you a very clean cut that needs little sanding. If you are talking about the end grain at the bottom of the bowl then it is cutting from the rim down to the bottom, light cuts and getting the angles right so that the gouge is cutting, not scraping. If it is a square bottomed bowl then you could cut either way, but getting the angle of the tool so that you are producing fine shavings, not dust. Again, the video is very good, I think. Start from that point, get it right and then experiment from there would be my advice. Light cuts with sharp tools gives a good result, but the tool has to be cutting, not scraping to get a really good finish.

As has been said there are different ways to produce good results. I rarely use scrapers, some people would use a scraper on end grain, in fact on lots of things, I just think gouges are quicker and for me produce a better result. Again, to get a good result they need to be sharp and presented to the wood at the right angle to get a fine shaving, not just dust.

Fingernail is the shape of a grind, long and strong is just a heavier bowl gouge and the superflute is the shape of the inside 'U' on a particular bowl gouge. I have one, can't say it is much different to the normal 'U' in use. Just this week I used a spindle gouge on the outside of a large diameter 'bowl' I was turning as it was the right shape and sharp at the time and I could get the rest close so didn't need the strength of a bowl gouge. Nothing is hard and fast.

HTH

Johnny B

 

[Bob Chapman]

Hi Big Chief,

Johnny B has said it all I think. I'd only re-emphasize his advice on sharp tools and getting the correct angle - which comes with experimentation and practice.

Bob

 

[Bob Chapman]

Hello again,

Almost as soon as I'd written the previous post I came upon this:

http://www.woodturningdesign.com/askdale/18/18.shtml

I haven't read it all, but I assume Dale Nish knows what he's talking about!

Bob

 

[Jenx]

Hi - Bob & Chas, I'm right glad you have described in the way you have... I hollow my bowls inside, by starting at the rim and going towards the middle ( (left to right, if you will ), and was thinking that I was maybe doing something wrong !

A little mention on 'shear-scraping' if I can, as a relative novice : -

A good few months ago, I read here somewhere an excellent description which I'm sure was Tam's ( TEP ), describing how to shear-scrape with a 'conventional' scraper.. and he mentioned that caution was needed when doing so... I tried it at the time, and managed to scare 7 colours of the sticky stuff out of myself, as I was nowhere near cautious enough and managed to cause the tool to slam back onto the 'flat', with a catch that will live in the memory for quite some time to come yet :wink: .... definately a case of trying to run before I could walk.... so I left it alone.

However - recently I managed to get hold of a Sorby RS200-KT Multi-tipped tool, and have used the larger scraper-tip that comes with it to good effect in a shear-scraping fashion. I appreciate that my own technique may have improved a little.. but this tool is ( or it is in my hand, I should perhaps say .. ) infinitely easier and I think safer, to use in the shear-scraping fashion.
That said.. I appreciate the thinking that 'better to learn to use the few basic tools and save your money'..... but in this particular instance, I can only say that the use of this excellent tool has allowed me to make marked improvements on my finishing cuts and it inspires a high degree of confidence when using it. -- its very 'easy & friendly' to use.

Probably the best £40-odd quid I'd spent, for a long time - its made a big difference to what I've been making recently.

 

[rsser]

Yeah, I've moved away from conventional scrapers for bowl insides to this kind of tool too. The half-round shaft allows an easy roll to a shear angle. It's a pity though how poor quality the steel of the tip is.

Not hard to make your own. Grind an old HSS electric planer blade to shape using one of its existing holes for the mounting screw. Grind a flat on a bit of mild steel rod, tap for the screw and arrange a handle.

Mate a tool like this with an Irons toolgate and you can benefit from regular radius sweeping, as well as getting the rest some way into the bowl to reduce or eliminate vibration.