Tool rest or bigger gouge

[Kirk Amidon]

Quick background, been turning bowls up to about 11" diameter and maybe 6" deep on my lathe. Been having some challenges with the lower inside corners with vibration and cut quality.

This issue occurs when my gouge is extended furthest off of the tool rest - 3 to 4 inches as I make the turn. I'm using 3/8" gouge (has 1/2" shaft) never sure what size to call it. The tool rest is a standard 12" one for my Delta lathe.

From looking around, there are two things I might do which can help with the issue. First, it seems that when the gouge is not extended, there is not a vibration/quality issue, which leads me to the following: Should I get a larger gouge to help with dampening that vibration, say a 1/2" (5/8" shaft) or look into a "J" style tool rest which will get deeper into the bowls and reduce the overhang need? Each solution ends up around a C note.

 

[Mark Jundanian]

I suggest the toolrest solution. I think it is more important to get the work support close to where the cutting is happening. If that is not possible a heavier tool can help, but isn't the first choice solution.

 

[Roger Wiegand]

Either will help a lot. The J-rest is probably the best solution to your immediate problem. A bigger gouge will be more generally useful, making many cuts more stable without having to swap out of move the rest. Ultimately you probably want both.

Are you already angling your straight rest into the bowl while you hollow? It's hard to imagine just how you are getting to 4" off the rest in a 6" deep bowl.

 

[Ron Solfest]

What both Roger and Mark said, but I'll add that the 5/8 gouge (shaft) is my favorite gouge used easily the most so I'm pretty sure you'll end up with one of those eventually. I have an S tool rest, but almost never use it as angling the straight rest into the center of the bowl provides plenty of support for the size bowls you're turning I think. Taking a light cut with a sharp gouge can help. Sometimes for a deeper, flatter bottom (sharper shoulder curve at base) I use a bottom-feeder ground gouge (very steep ~ 75deg to 80deg bevel) to reach across base without running into lip of bowl with shaft.

 

[Kirk Amidon]

Thanks - Solid advice.

As for the long reach on smallish bowls. Maybe this is a technique thing, but my gouge is sharpened at 60* or so, and with the tool rest angled into the bowl, I get the tool closer to parallel to the rest than perpendicular, which makes for a longer overhang. An additional gouge with a steeper angle would help that, as will paying more attention to the secondary bevel.

The other minor issue, is that the banjo sometimes gets in the way and does not allow the rest to position where I'd like it.

 

[hockenbery]

Like above both will help.
get the Robust J-rest first. 5/8 diameter gouge is a good tool to have.

The biggest contributors to vibration when extended over the tool rest are
Resistance to the cut and Bevel drag.

reducing resistance to the cut - sharpening the tool, shallower cut, slower feed rate, higher lathe speed.

reducing bevel drag - don’t push the bevel against the wood float it over the cut surface, clean the bevel, shorten the bevel length by grinding the heel off the bevel or creating a secondary bevel.

 

[robo hippy]

If I have to reach out 3 or 4 inches, and don't have the proper bowl rest, then I use a 5/8 gouge. 3/8 is too thin to hang that far off without having vibration issues unless you are only doing 'whisper' cuts that yield fine tiny shavings that float in the air.

robo hippy

 

[Kirk Amidon]

Looking at Robust, and about to call them with one question, but another can probably be answered here. 9" or 14" J rest?

 

[Mark Jundanian]

That depends on how deep you need to reach into your piece, and the width of the opening you're accessing through. For an open bowl my 9" Robust will reach about 4", allowing for the banjo. My Hannes J is about the same, but because of the thick rod design I can get that reach through a narrower opening. The Robust J needs a wider mouth because of the supporting structure and the 14" will need a bit more than the 9".

But here's the bad news, you're going to need and use more than one rest. I don't consider myself extreme, but I have 7, and the only one I don't use is the OEM. Maybe I should get that 14" Robust?

 

[Kirk Amidon]

That depends on how deep you need to reach into your piece, and the width of the opening you're accessing through. For an open bowl my 9" Robust will reach about 4", allowing for the banjo. My Hannes J is about the same, but because of the thick rod design I can get that reach through a narrower opening. The Robust J needs a wider mouth because of the supporting structure and the 14" will need a bit more than the 9".

But here's the bad news, you're going to need and use more than one rest. I don't consider myself extreme, but I have 7, and the only one I don't use is the OEM. Maybe I should get that 14" Robust?

As it sits, I have 5 straight rests, 6" (x3), 12", and 24". No curved yet.

Is there a downside to getting the 14 vs 9? Seems that the 9" does not offer much in the way of length over a 12" straight, but the curve would be helpful.

 

[William Rogers]

I have both the 9” and 14”J rest. For an 11” bowl the 14” rest would be my choice. For a 8” bowl the 9” rest would be my choice. When thinking about the size the 9 seems more like the straight 6” and the 14 seems more like the 12” straight.

 

[hockenbery]

I have the 14. The largest bowls I do are a bit over 17” and this rest works great.
For any bowls too small for this j rest the straight rests work fine.

I do have a smaller J for my Jet 1221 to supplement the rest that comes with it which is too shorty to hollow a 10” bowl comfortably.

 

[Kirk Amidon]

Update: Just got off phone with Robust, who says neither the 9 nor 14" rests will fit my lathe. Logic was two fold, one that the height of the tool rest is 2 3/8" tall, excluding the post, and even with a short post it would be too tall.

What other options might I have? Again, a 1970's vintage Delta/Rockwell 46-450 lathe.

 

[Roger Wiegand]

It's moot I guess, but I have both and never use the smaller Robust J rest. The straight rest gets me where I need to go on pieces where the small one might be appropriate.

Look at Hannes tool for lower profile J rests, possibly.

 

[Mark Jundanian]

Yes, I would send you to Hannes, too. There are other makers of curved tool rests, but names escape me at this momment. Google curved lathe tool rest and I am sure you'll see some other choices.

 

[Bill Boehme]

This issue occurs when my gouge is extended furthest off of the tool rest - 3 to 4 inches as I make the turn.

Your statement about "making the turn" leads me to suspect that your bowls might have a cross-section that looks something like this: \______/

• Are the sides somewhat steep and straight (45° is borderline steep and 60° is very steep)?
• Is the bottom somewhat flat?
• Is there a fairly tight transition area where the side and bottom intersect?

A bowl with this kind of cross-section presents some challenges, especially at the corner, and can result in excessive tool overhang. I prefer turning a bowl that has a continuous curve from rim to bottom with no discernable transition from side to bottom. Some bowl cross-sections that I like are parabolic, elliptical, catenary, and semicircular sections. I don't try to exactly replicate any of those forms, but I use them as guidelines. Another thing that could help would be to drop the tool handle and roll the tool over so that you are making an arcing cut towards the interior center. You would probably need to find a mentor to demonstrate this technique.

 

[odie]

There's a lot of good advice in this thread, and all of it will help. It's likely that a combination of these things could result in a cleaner cut than any one by itself.

Al is correct to bring up the "sharpness" issue. How sharp a gouge is, is probably the one single thing that solves more problems than anything else!

-----odie-----

 

[Kirk Amidon]

Thanks again. Just went out and staged a couple pictures for clarity.
Here is the overall shot, due to rim the banjo cannot get any closer to bowl.



Second is a look at the reach to the actual corner. I think Bill has a point, that my bowls are a bit too sharp a turn, as the tool is still close to 3" off the rest when perpendicular into corner.



Finally, the typical gouge tool rest relationship as the bottom of bowl is cut.



Hopefully this will help provide a better picture of what I'm doing, and basis for suggestion.

BTW - I'm impressed at how helpful everyone here is, and not just on my threads. I've spent hours combing over the past posts and have learned a lot in the process, and have found it has really helped my progress.

 

[Lamar Wright]

First.........I always try and get the tool rest as close to my work as I can without causing an issue. As Al and Odie mentioned always keep your gouge sharp!!

 

[Mark Jundanian]

I think a J shaped rest will help your situation. If there is a local club in your area perhaps there would be an opportunity to borrow one to try?

 

[Karl Loeblein]

What is your tool rest shaft diameter? If height above your tool rest is an issue then you should be able to find a S or J curve tool rest made from round bar stock. Something like this one from Lee Valley that can be ordered with different post sizes:

https://www.leevalley.com/en-us/sho...ve-bowl-supports-for-modular-tool-rest-system

 

[odie]

Finally, the typical gouge tool rest relationship as the bottom of bowl is cut.

After you reach "the corner", sometimes it's preferable to reverse the orientation, and do a pull cut to the center.....needs to be right on the centerline for good control. As you approach the very center, the angle needs to be increased a bit. (Make sure you leave the teat in the very center, as that helps keep the tool from skipping over the center. The teat is easily sanded away later on.)

The curved tool rests are a great advantage for this kind of interior work. I have several brands.....Hannes, Robust, Oneway, and recently added a couple Robo Tool rests. All of these have their most useful applications. (Note: @robo hippy is discontinuing his line of tool rests, so check his availability. AFAIC, Robo's rests are extremely well designed and built, and are the best of those I'm familiar with.)

-----odie-----

 

[George Kuipers]

Update: Just got off phone with Robust, who says neither the 9 nor 14" rests will fit my lathe. Logic was two fold, one that the height of the tool rest is 2 3/8" tall, excluding the post, and even with a short post it would be too tall.

What other options might I have? Again, a 1970's vintage Delta/Rockwell 46-450 lathe.

Have a look at the Oneway j rest,very short post.

 

[Dean Center]

I'm with Al. I think you need to look at your gouge for the fastest, cheapest way to improve things. The larger diameter gouge will help, but a shorter bevel can really make a difference curving through the transition zone. 30 seconds on the grinder to resharpen the edge and remove the heel will answer the question.

 

[robo hippy]

I had one of the Oneway inside rests, and didn't like it. The section of an arc style fit well inside a bowl that is already 80% roughed out, but a pain for a solid blank that you are roughing out, and required a lot of moving the banjo and adjusting the set screw. Also, with the Oneway, it would vibrate when you were roughing off of the tip/end of it.

robo hippy

 

[Kirk Amidon]

For closure, I could not find a rest in stock which had a short enough post for my lathe, so pulled trigger on a 5/8" gouge from D-Way. Figure one way or the other, I would have ended up with one anyway. Thanks again for the thoughts/ideas.

 

[Kevin Jenness]

For closure, I could not find a rest in stock which had a short enough post for my lathe, so pulled trigger on a 5/8" gouge from D-Way. Figure one way or the other, I would have ended up with one anyway. Thanks again for the thoughts/ideas.

A hacksaw would take care of the extra post length.

 

[Mark Jundanian]

For closure, I could not find a rest in stock which had a short enough post for my lathe, so pulled trigger on a 5/8" gouge from D-Way. Figure one way or the other, I would have ended up with one anyway. Thanks again for the thoughts/ideas.

I think you'll be pleased to have that gouge.

Is your fit problem the tool post length or the height of the rest component itself?

 

[Kirk Amidon]

I think you'll be pleased to have that gouge.

Is your fit problem the tool post length or the height of the rest component itself?

The issue is mostly that of post length - it is a 12" lathe. There are two versions of banjo i have for this lathe, a light duty and a heavy duty. The HD one is set up so the locking mechanism limits the amount the post can be inserted, the stock 12" rest has just under a 3" post which works fine. The lighter duty banjo does not limit the post insertion length, so the limit is the bed itself, so a slightly longer post is possible, so a total of about 6" is ok, given it is a 12" lathe. The Robust rest itself is likely too tall, which was what they said.

Was not sure about cutting down a post, but have a longer one I can try to cut.

 

[Mark Jundanian]

And as I recall you already have several straight tool rests, so clearly there are configurations that can fit (though maybe special order).

Were you able to check out any of the rests made from heavy round bar stock like the Hannes? I'm thinkin' in the future that's going to be your best bet.

 

[Bill Boehme]

As Mark said, a hacksaw can be used to shorten the post. On my previous lathe, I had to shorten the posts of a couple of tool rests. The posts are either mild steel or ductile cast iron and easily cut with a hacksaw and cleaned up with a file.

 

[robo hippy]

Well, easy to cut with a hack saw if you have an hour or so..... Jigsaw with a metal cutting blade a bit better, angle grinder with a metal wheel would take a couple of minutes...

robo hippy

 

[Bill Boehme]

Reed, maybe it's time to buy a new blade for your hacksaw. It shouldn't take but a minute or three to cut a tool post with a hacksaw.

 

[Gerald Lawrence]

When I bought my Robust rests I was told that Brent actually recommends a longer post and then cut to needed length. Yes Reed I used a hacksaw, maybe 5 minutes if that

 

[Timothy Allen]

I, too, have cut down a tool rest post, with a hacksaw, and in a few minutes.

One tip -- grind or file a chamfer on the bottom edges of all your tool posts, makes them easier to insert into the banjo (especially if you have a dual wedge locking mechanism, as opposed to a simple set screw).

 

[robo hippy]

Well, I haven't used a hack saw in years, so maybe my blades were dull. Same with the metal cutting blades in the jigsaw. Now that I have an angle grinder, that is all I use.

robo hippy

 

[John Tisdale]

Want a freebee? I have a J-rest for my Oneway 2424 - has a 1"-dia post that will, no doubt, need to be cut off.
Was custom made and is useless for hollow-forms - my taste in shiny objects is evolving.
Just send your cell number to my inbox and I'll send a pic.

 

[Kirk Amidon]

Follow up: I've received and put a handle on a D-Way 5/8" bowl gouge, and have been impressed with how much more mass it has over the 1/2" sized gouges I have. Additionally, I was able to cut down a nova post I had, which will allow me to try some additional rests, and have another curved rest on it's way. (Thanks John)