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Terry Buetikofer
01-06-2011, 7:34 AM
Hi

I'm a new turner, and need some advice. I have a BB 5/8 bowl gouge and a DT 5/8 V gouge. Both have the same grinds. Because of something I'm doing wrong the BB cuts better then the DT.

I'm using the Wolverine sharpening jig. I have a ~45 degree fingernail profile. I started with the recommended grind on the DT, but changed it to eliminate that as a possible reason for the difference in cuts.

I'm not flaming the DT and know the DT is a much better gouge, but I can't figure out what I''m doing wrong.

Thanks in advance for any help.

tom martin
01-06-2011, 8:37 AM
Terry,
I have the same problem with DT gouges. I have both the 5/8 and 1/2 inch and have ground 1/3 of it away trying to get it to cut as well as my mastercuts or BB gouges.Last week I gave up on them and they lost their spot in my tool rack!
I have a tormek and a delta vs grinder with wolverine fixtures. I assumed I was doing something wrong also, but I 've run into other turners at my club that have the same issue.
Tom

John Keeton
01-06-2011, 9:39 AM
If you guys are talking about Doug Thompson gouges, why not just send them to me, and I will be happy to replace them with brand new BB gouges for you!!:D Well, probably not for you, Tom, since there is only 2/3 of yours left!;)

In all seriousness, I think the difference in the two is that the BB (M2 HSS) will probably take a sharper edge than will the Thompson gouge, but it will lose that sharper edge much, much quicker than will the Thompson. I have had excellent experiences with Doug's tools, and get great cuts with them, as apparently most everyone that has them. I can only surmise that it is something happening on your end. Without being there, and observing the issues, it would be hard to say.

Chris Stolicky
01-06-2011, 10:05 AM
I agree with John.

I have the same two gouges and I can get what seems like a sharper edge on the BB. I think that part of it is the steel, but the other part is that the actual metal on the sides of the flute on the BB are so much thinner. I tend to only use is for really fine, shearing-type, cuts.

The Thompson has noticeably more weight to it, can extend further off of the tool rest, and holds its edge much longer than the BB. The powder metal edges do seem to differ from pure M2 steel in all of my tools.

I have also evolved to maintaining Dougs grid (or close to it) on his gouge, but I use my Ellsworth jig for a sweeping grind on the BB.

Good luck, and just keep at it.

Kyle Iwamoto
01-06-2011, 11:07 AM
I will also agree with John and Chris. I have DTs and Sorbys, and I feel I can get the Sorbys sharper. SO, the DT's are the workhorses, for roughing and the Sorbys are the finishing gouges. I most always reach for the DT first. However, I just recently bought a Oneway 5/8 and been very happy with that. I have a Tormek. The Oneway is sharpened at a different angle, I tried to match the original (very strange) grind.... The Sorby and DT's are all the same grinds.

Steve Schlumpf
01-06-2011, 12:12 PM
Terry - Welcome to the Creek!

Just my opinion on this as I am not a metallurgist - but there is a difference in steel and you can see that difference when viewing the edge. I agree that the DT will hold an edge longer and, while I have other brands of gouges, the DTs are the only ones I use anymore. One thing you didn't mention is the grit on your sharpening wheel. I changed my slow speed grinder over so that I use a 120 and 150 grit wheels. The 120 takes a little longer if reshaping a grind but most times use the 150 just for a quick touch-up. Finer grit wheel + light pressure and you have one heck of a sharp edge!

tom martin
01-06-2011, 12:54 PM
I'm not sure it's the metal that I have trouble with. I think it's more the geometry of the the gouge. The flute on the Thompson is much shallower than the Oneway or BB.I can get my Thompson gouges very sharp, but they do not cut as quickly or with as much control as my oneway (or BB). Believe me I wanted them to work and the reason I've ground off a third is that I thought I must be doing something wrong and kept trying different angles and sweeps. I have the utmost respect for Creekers and rely on this forum for tool review. I believe that all the positive Thompson reviews are sincere and accurate, I just can't get them to cut!
John, I would be happy to send you some photos of my gouges to see if there is enough steel left to make it worth your while (and postage)
Thanks Tom

Doug,
I ABSOLUTELY love the two Thompson detail gouges I have, and my next skew will be coming from you.

Steve Schlumpf
01-06-2011, 1:00 PM
Tom - any chance you can post a closeup photo or two of your grind? Might be able to figure out what is going on...

Dale Miner
01-06-2011, 1:44 PM
My guess is it is more of a geometry issue than a metalurgical one. The grain structure of the cryogenic abrasion resistant metal is at least as fine as the M2? in a BB gouge, and should take at least as keen an edge and hold the fresh edge longer.

My first bowl gouge was a homemade one from O1 and had a U-shaped flute. That is the shape flute I learned to turn with. I did get tired of it not staying sharp, so bought a BB gouge. I hated that gouge from day one. The flute has a deep V shape with a small radius in the bottom. I could not get used to the flute shape, especially on the inside of a bowl, and went back to the homemade U-flute until I had a chance to buy a U-flute gouge from Doug. I will add that even though Doug has V-flute gouges, they do not have as tight a radius in the bottom as the BB gouge I have. As the radius at the bottom of the flute changes, so does the tool presentation. A larger radius requires closing the flute (pointing the flute away from the wood) more when working inside a bowl. Also, when making the initial presentation to the rim of the bowl, the flute needs to be closed moreso than with a V-flute. The smaller radius in the bottom of a V-flute allows for a more forgiving flute presentation when starting the cut. A open flute presentation with a U-flute will skate.

From looking at Sorby gouges, they have also have what I consider a 'tight' radius in the bottom of the flute, and like the BB gouge, I prefer not to use them for that reason. Each flute geometry has its own techinque.

From my way of thinking working the inside of bowls;

Larger radius = smoother cuts and more critical presentation.
Smaller radius = Less smooth cuts, and more forgiving presentation.

I can have spectacular catches with any flute shape however :) .

John Keeton
01-06-2011, 1:47 PM
Dale - excellent input!! Having only used a Thompson V gouge, I had never considered this. I do have a couple of smaller P&N gouges that I use for detail work, etc., and they do have a different feel to them.

Jon Prouty
01-06-2011, 3:18 PM
I have been using Dougs V shaped bowl gouges for a couple weeks now and can attest to the different feel / presentation to the wood from the U shaped BB tool. It took a little retraining to my brain but I think I found the sweet spot now. I expect that Dougs U shaped gouge will be much more similar to the U BB that I had before. Also, I believe Doug receommends the V shape for more wet turning than dry blanks... but for me I usually turn dry and bought the V shape anyway.
-----------------------------------------
Actually lifted this from Dougs FAQ on his site:
V Shape or U Shape that is the question!
If you ask 100 people the same question you’ll get 101 different answers. I prefer a V shape because the V shape flute can be very aggressive when roughing especially on green wood. When you need to remove a lot of stock when roughing a bowl or turning a hat where 99% of the blank ends up as shavings the V shape is the only way to go. The small nose radius is not grabby when entering a cut and can be used to create details. Because the wings tend to be longer on a V shape tool scraping is easily done on the outside of a bowl. In the past a V shape flute was known to clog with shavings, the design of this flute was changed so it doesn’t happen.

The U shape flute has some strong points especially when turning dry wood. The large nose radius allows the tool to shear the wood which is good to prevent tear out, the finish cut inside a bowl or long sweeping curves outside a turning are just two examples where this tool excels.
-----------------------------------------

Good luck - hope you find the sweet spot.
Jon

Terry Buetikofer
01-06-2011, 3:57 PM
Thanks for the comments.

Tom: Glad I'm not alone!

Steve: Thanks. I'm using a 120 wheel. I'll also post some picts later today.

Jon: I'll keep looking for the sweet spot.

I really like the overall feel of the DT, and know I'll love it after I get over this hurdle.

Bernie Weishapl
01-06-2011, 4:54 PM
You have gotten some good advice and I do agree with Jon. I use my Thompson V gouges for hog off wood, the U shaped for finer cuts and the P & N conventional for the finihsing cuts on most bowls.

Doug Thompson
01-06-2011, 5:41 PM
Terry,
Do take a picture so I can see what the problem is. The grind right out of the package is a standard grind that does most everything well... when it's changed the cutting angles could be lost. The basic grind is what John Jordan, Bill Grumbine and Jimmy Clewes use on these tools and they have no problem with sharpness, cutting angles or lack of control. Keep it simple.

Thomas Bennett
01-06-2011, 6:34 PM
For us novices out here, could someone tell me what a "BB" is? I read all the posts hoping to figure it out.

I got that "DT" is Doug Thompson and have a full selection of them.

I use the Grumbine for heavy roughing as others mentioned. I'm saving up to buy another and grind it with a steeper angle for really deep cuts.
I bought the 1/2 "v" and "u" and the 3/8 (I think) 'Jimmy Clewes", all of which I like. I've been using the Jimmy Clewes as a sort of detail gouge. One of my favorite guoges, though, is a 3/8 Glaser made of powdered metal. Like others mentioned, it just seems to be sharper than any other tool I have.

Thom Sturgill
01-06-2011, 6:47 PM
Thomas , BB refers to 'Benjamins Best' sold by Penn State (PSI) and others.
For those wanting a tighter V, look at Doug's Jimmy Clewes signature gouges. I have 2 and love them.

Jeff Nicol
01-06-2011, 8:32 PM
I have 2 5/8 Bens best an 5/8 Ellsworth signature and a Thompson 5/8 "U" and a 1/2" Thompson "V" gouge. What I have noticed is the BB gouges are semi-"V" the Ellsworth is a bit more of a "V" but ground at a longer sweep. The Thompson "U" is definitley a "U" and not a modified or semi "V". The Thompson "V" is very similar to the Ellsworth. That being said I can get the BB to sharpen at any angle, sweep or whatever, but as already said they don't stay sharp as long but cut like the dickens when sharp. The Ellsworth stays sharp a long time and is one of my all time favorite gouges and the Thompson "V" is in the same category as the Ellsworth gouge. With all that being said I had some issues with the Thompson "U" gouge right away and I thought that I was not getting a good edge on it, but it was sharp as sharp could be so I had to figure it out and what I found out was that how I addressed the wood with the gouge made the difference in how it performed. I did change the standard grind a little bit on the Thompson "U" at first but I think I am back pretty close to how it came to me ground at. I use the "U" for mostly rough outs and some shear scraping cuts but for the best finish I always end up with the Ellsworth or the Thompson "V". I may have to get another one and put a longer sweep grind on it to see if I like it better that way, so I guess I have tried a lot of tools and I will try some others some day soon.

I am a tool addict and my name is Jeff!!

Find the sweet spot,

Jeff

Harry Robinette
01-06-2011, 9:40 PM
Hi All
I use DT's now all the time,one thing I haven't heard anyone talk about honing.DT gouges take a hone unbelievably well,I hone all my tools and I own sorby,P&N,crown,oneway,bb,ashley iles,henry taylor,and even woodriver I have ground and honed all of them and my true opinion Doug's tools get shaper then any of them" IF " you hone them.Also if you try honing your tools I do believe you will see a marked different's in the sharpness and cutting of any tool you wont to use.
I know Doug and his Guarantee he'll stand behind his tools.But try honing I think you'll notice a marked different's in the sharpness. Just my opinion.
Harry

Rich Aldrich
01-06-2011, 9:47 PM
I have two Doug Thompson V gouges, a 1/2 and 5/8. The first time I used them was on cherry burl. I primarily used the 5/8 on a cherry burl. I made two bowls and a platter without having to sharpen the gouge. The burl was dry, so it was extra hard and came out beautiful. This is the first time I was able to start out with 120 grit when sanding.

tom martin
01-06-2011, 9:48 PM
Well I tried....several times to get a decent picture. I wasn't very successful. 176748176749
The thompson is on the left in the second photo the BB is on the right. They both have the same jig settings and were freshly shaped and sharpened. Looking straight down on top of the Thompson you can see that the bevel kind of wraps around the radius of the tool.I thought this might have been the issue and most regrinds involved trying to minimize this.
To be clear, I can get a decent cut with the Thompson, but not as good as I can with either the Oneway or BB. I did follow Dougs original grind for a week or so when I first got my gouges and then started all of the trial and error trying to get it to cut as well as my Oneways.
I learned to turn on a Oneway and that was the only gouge I had for years until I got a set of BB about four years ago. I've had my Thompsons for about a year and a half. I think Jeff is probably right on about tool presentation.
I think I'll retire my Thompsons until the AAW show and bring them along so I can watch the proper presentation with proper grind... I'm not opposed to change... life is scary when your alone in the Vortex!!!:eek:

Rick Markham
01-06-2011, 11:14 PM
I have a bunch of Doug's tools, but I have no experience using anything else (I'm spoiled). I have both the 5/8" U and the 5/8" V, I use both almost interchangeably, but prefer the U for finishing cuts and "end grain" at the bottom of the bowl. After watching a Mike Mahoney video, I did notice that I had to present Doug's tools, every so slightly different (from his demonstration) for them to perform at their best, it was subtle. I also changed the grind on mine, I kept the angle the same but swept back the wings, for me they work better, and my turning improved because of it. I actually want to give Doug a call and pick up another 5/8" U and 5/8" V so I can have a set with standard grinds. I agree with the honing statement, you can refine the edge with honing. For me I grind on a Tormek and they are pretty darn razor sharp after a 20 second touch up.

This is just my opinion, and it's worth what it's costing ya, I made very minute changes on the grind at a time until I found my sweet spot, and have since stuck with it. You might want to stick with a grind on them until you figure out the presentation to the workpiece, then work a grind from there. Maybe I had an advantage, of not knowing what I was doing and having to "play" with them a bit, to figure how they cut and worked to their potential. This thread makes me want to stick with what I know, which means "I'm stuck with Doug Thompson's Tools" and I am A-OK with that!!!:D

Terry Buetikofer
01-07-2011, 9:09 AM
Again, Thanks for all the comments. Here's a link to some pictures: https://docs.google.com/document/d/1GTv22IyEs00PhrwcHffY_Akd_8NU30j2uG2CbcSIVpI/edit?hl=en&authkey=CMOal74B

I kept the original grind for several weeks, then last week changed to what you see. This is the first time I'm sharing a google doc this way. Let me know if you have any problem viewing it.

I'm still digesting all the info here...

Doug Thompson
01-07-2011, 9:31 AM
Terry,
Thanks for posting, the nose angle to the very short upright wings. Don't grind anything until I get a picture posted later tonight that will show the grind a bit better. Give me a call at 440-241-6360

Doug Thompson
01-07-2011, 12:39 PM
See the new thread about grinding.

John Keeton
01-07-2011, 1:57 PM
Terry, Doug has provided some good pics in the other thread, and sounds like he is on top of helping you with this. One observation for your benefit, and others, is that you have developed a "dip" in your side grinds up close to the nose of the gouge. That will create multiple problems for you. The sweep needs to be convex, or at the worst, flat. Concave is not good.

Terry Buetikofer
01-09-2011, 8:09 PM
A big THANK YOU to Doug Thompson for helping me out with this. After speaking with Doug I realize the grind was all wrong. Thats been fixed now (back to his recommended grind), and the gouge is working great.

Thanks for everyones comments. I'll be trying out some of the suggestions...

Dan Kralemann
01-11-2011, 2:09 AM
See the new thread about grinding.

Where is this grinding thread?

Dan Kralemann
01-11-2011, 2:42 AM
For us novices out here, could someone tell me what a "BB" is? I read all the posts hoping to figure it out.

:confused: I have also not known what some of these abbreviations are and I have not found a page on this site that lets me know what they are. I belong to a website called Badger & Blade, and they have B&B Abbreviations/Acronyms, under their Miscellaneous section which is listed on their Wiki information page http://wiki.badgerandblade.com/index.php/Main_Page. I am respectfully requesting that an Abbreviation/Acronyms section be installed on this site. Thank you. Dan

Rick Markham
01-11-2011, 5:23 AM
Dan, BB stands for Benjamin's Best ;)

Rick Markham
01-11-2011, 5:27 AM
Dan, here is the thread, things move pretty fast in the turner's forum. Hope this helps! http://www.sawmillcreek.org/showthread.php?156654-Bowl-gouge-basic-grind-profile

John Keeton
01-11-2011, 5:47 AM
I am respectfully requesting that an Abbreviation/Acronyms section be installed on this site. Thank you. DanDan, this thread (http://www.sawmillcreek.org/showthread.php?17995-List-Of-Acronyms-Update-3-15-05)may be helpful to you regarding acronyms!

Dan Kralemann
01-11-2011, 11:20 AM
Thank you Rick and John.