Dangerous? You decide.

[TurtleTom]

I've been having a lot of tear out and shattered blanks when doing punky wood, segmented wood especially, and just difficult woods in general so I invented a new technique:
I put a 43 grit sandpaper flapper disc on a 4 1/5" grinder and sand the difficult blanks within a few thousand of the bushings. I use failed slimline uppers (or lowers) fore and aft of the blank on the 7mm mandrel to keep the sander away from the chuck and the mandrel saver. If you have a lot of bushings that would work too. RPM doesn't seem to matter very much.
I've had total success with the technique and generally about 20 to 30 seconds is all it takes to get to the bushings. Don't use much pressure as that could distort the mandrel. Don't quote me on the time because I'm very focused on what I'm doing and could be estimating the time all wrong.
Caveat: I've been using grinders for 55 years and am quite expert in their use having worked as a machinist and oilfield weldor for many years and even after. Starting out I was cut pretty bad with a cup brush and a good friend lost his life with a 7" grinder without a blade guard that shattered and severed his femoral artery. He never even got the door open on the pickup truck. Be careful with these things. Don't just use good judgement, ask an expert about what you're about to do with high speed tools like 10000 rpm grinders.
I'd be very interested in feedback from experienced turners and tool handlers about this technique.

 

[Woodchipper]

Can't help with the questions about wood but I do appreciate the caveat about safety with any type of tools- power or hand. It only takes one second to have an "Oops" occur in the shop or on the job. I'll confess- I had TS kick back about three or four months ago. I was running a piece of wood through the TS and, for some reason, let up on the pressure on the wood. The blade caught it and I got my first kick back in 40 years. I'll be 110 when I get the next one.

 

[TurtleTom]

I'll be 110 when I get the next one.[/QUOTE]

I've said that twice now. A long time ago I remember saying "it's only 1.5 HP how much damage could it do?"

 

[leehljp]

Tom,

That is one great way to handle punky wood and segmented wood too. I often comment when people bring up their "one way" and have mastered it, then try a different way (more than once) to increase their expertise field.

I "think" someone else mentioned recently using a hand grinder with a sandpaper grit to get them round. Great minds think alike! :highfive:

I am going to try this in the future myself. It will probably eliminate or reduce the problems caused in segments and heat caused separation.

The "old way" on segments was to wrap a blank with cord/string and Soak in CA. In the last two or three years, Gauze wrapped blanks and soaked in CA was the way. I have three hand grinders and I am going to dedicate one to this one method. Thanks for posting. I'm still learning!

TOM - You do realize that you are just digging a deeper financial hole for pen turners needed tools - don't you! :biggrin:

 

[Woodchipper]

Lee, could you tell what hand grinders you are using? Might look into that for future reference. I have a generic Dremel from Lowe's. Is that close to what you have?

 

[TurtleTom]

I don't think Dremel makes a heavy duty grinder. Mine is a 4.5" Dewalt 10,000 RPM. I've never seen one smaller than this. This is the tool weldors attach a 4.5" brush onto to clean slag off 5P and 6011 welds, especially on large pipe. There is nothing better for the purpose.

 

[Charlie_W]

I am pretty sure Tom is talking about an angle grinder with a flap disc.

 

[TurtleTom]

I am pretty sure Tom is talking about an angle grinder with a flap disc.

I never think to call them angle grinders. Thanks.

 

[Curly]

Tom you have come to the same turning method using an angle grinder that George (Robatucon) started promoting a number of years ago. I'm sure others "invented" the power tool gouge before that and more will in the future too. Doesn't take anything away from the accomplishment though.

 

[leehljp]

I have a similar Dewalt model that Tom has, along with a Ryobi 6.5 amp and a similar sized one that I bought in Japan. All corded ones.

I also have the Ryobi 18V cordless and while it does the job, it is a little unbalanced to me with the heavy battery way out on the end. I take this one when the job is not close to outlets.

Tom: "I never think to call them angle grinders. Thanks."

lol. Me neither!

I used a large 9 inch one back in the early '70s in the paint shop for body (car) repairs. We did not call them angle grinder back that I can remember. I still have my 9 inch from that I bought when I worked at the body shop and it still works well.

 

[TurtleTom]

I wasn't conceited enough to think I was actually 1st. Just 1st for me.

 

[Curly]

I wasn't conceited enough to think I was actually 1st. Just 1st for me.

That wasn't what I was getting at. You wanted feedback and George has done it a lot. Contact him and he will be happy to talk about it or search back in his threads and posts for what he said.

 

[triw51]

I was having trouble turning palm wood it kept splintering apart even with sharp tools. What I did was glue some 36 grit sand paper to a paint stick and using the tool rest I used that to "turn" down the blank to with in a few thousands of the bushing (I had wrapped the bushings with blue tape to protect them) Similar idea different method. Hope this helps some one else.

 

[BeeAMaker]

That would be cheaper than stabilizing the blanks first. After going though 2 gallons of stabilizer, this might be an alternative.

 

[JPW062]

"power Skew"
RO sanders from festool are supposed to be the best.
Not cheap, but they have lots of other advantages also. Should be best dust collection you have ever had on a lathe.

 

[PatrickR]

I have a couple Festool sanders and a Vac. There is nothing better. I have not tried this technique but will.

 

[Curly]

Correct me if I'm wrong but doesn't the dust collection rely on the sanding pad of a random orbit sander pad being flat on the surface. The RO sander on a pen blank is only going to have contact on a line a fraction of an inch wide, so not likely to capture much if anything.
Patrick posted while I was typing so he will have to confirm when he tries it.

 

[TurtleTom]

I bought the sanding pad from Lowes's.
Everyone is correct about the dust: It's horrible, complicated by the woods I'm turning seem to be all toxic.
I use a high speed fan to carry dust away from the lathe. since I have a huge beard, dust filters don't work on me so I discovered maybe a better way. I have some excess children's T shirts left over from some airbrushed T shirts I made for some kids. I pull the T shirt over my head down to my nose. I'm breathing through a very large volume under my neck and down to my chest so the dust doesn't enter at all. I can't smell any of the wood till I pull the shirt down.
I once tried making a polka dotted pen but it came apart under the cutter. I'm going to try again using the sanding pad.

 

[PatrickR]

Correct me if I'm wrong but doesn't the dust collection rely on the sanding pad of a random orbit sander pad being flat on the surface. The RO sander on a pen blank is only going to have contact on a line a fraction of an inch wide, so not likely to capture much if anything.
Patrick posted while I was typing so he will have to confirm when he tries it.

I don't think a RO sander would work for this. It relies on friction to drive the action. An orbital would be the way to go. I will try it and report back. The Festool system is strong enough that the vac has to be turned all the way down when sanding a flat surface or the sander is sucked down.

 

[Curly]

I have Dynabrade RO air sander and they need the friction to operate properly too, but as I don't have an electric powered one I didn't remark on that. Dynabrade do make gear driven types that spin an eccentric pattern all the time. I don't know if anyone makes an equivalent electric. I doubt the orbital will be as effective as an angle grinder for this application.

 

[JPW062]

Festool RO FEQ series sanders are gear driven. RO is Rotex, not random orbital. I don't think it needs any pressure to function. It will certainly spin without pressure. The Festool RO series is quite similar in design to an angle grinder. You don't apply pressure when sanding. You turn down the vac so it doesn't suck the tool down to the surface and let it float.
For this use you can turn up the vac as it is not on a flat surface, so won't suction down.
The dust collection probably isn't as good as a flat board, but probably better than anything else on a lathe. On a flat board with suction down the Festool sanders will pick up saw dust for 1/4"+ past the pad. Maybe 1/2".
https://www.festoolusa.com/products...ric-sander-rotex/571810---ro-150-feq-plus-usa

I will see if I can borrow an RO 90 from work and make a video.

 

[TurtleTom]

IMO if it isn't powerful enough to require a 90 degree handle just to manage the torque, it won't be heavy duty enough to keep up with the angle grinder.
That's a helluva good looking sander though, but I guess they make the best hand tools out there judging by the prices.

 

[PatrickR]

Ah, i was interpreting it as random orbital and didn't even think of the product name. That is one I have though. I'd guess the only real advantage over an angle grinder would be dust collection at the source.

 

[TurtleTom]

Ah, i was interpreting it as random orbital and didn't even think of the product name. That is one I have though. I'd guess the only real advantage over an angle grinder would be dust collection at the source.

I doubt dust collection is remotely possible turning a blank down in 20 seconds without serious vacuum near the tool rest. I'm hoping to get that set up soon.
That's some nice tools you use though, wish I could afford them.

 

[JPW062]

IMO if it isn't powerful enough to require a 90 degree handle just to manage the torque,

Actually, the RO sanders do have 90 degree handles and it is highly recommended you use them when in RO mode. If letting it float over wood it isn't absolutely necessary, but if you want to really take material off and lean into it, it sure helps a lot.
Most dealers will have an RO 150 you can demo. Stop by and give it a whirl.

How can you afford to waste the time you are by not using those tools?

 

[dogcatcher]

This thread posts 11, 12 and 14. http://www.penturners.org/forum/f14/turning-synthetics-skew-151350/#post1949744

 

[randyrls]

This is a great conversation. I have a large dust collection hood behind my lathe. It goes on a bar that clamps to the lathe bed ways and is adjustable. I run my lathe in reverse and make sure that the set screws are tight to keep the chuck from unscrewing.

 

[TurtleTom]

Robutaction sent a link to the definitive article on the subject. Bring a lunch.

http://www.penturners.org/forum/f30/blowouts-my-solution-110460/

 

[crokett]

I'm going to have to try this technique on some black palm. I have 1 or 2 blanks that I've had for several years, because the first 3 or 4 I shattered trying to turn them. i also wish I knew about this trying to turn some honeycomb aluminum I cast several years go.

 

[TurtleTom]

I'm going to have to try this technique on some black palm. I have 1 or 2 blanks that I've had for several years, because the first 3 or 4 I shattered trying to turn them. i also wish I knew about this trying to turn some honeycomb aluminum I cast several years go.

I cut black palm with a cut off tool, pushing in rather than sideways cuts. Never had any problems. It really doesn't take any longer that way, I've had people get indignant about this technique even though it works perfectly with a sharp tool.