Problem with wood pens

[Ron in Illinois]

I have learned all I know about turning from the school of hard knocks and
watching videos and reading. I am getting along fairly good with acrylics
using carbide tools.
The problem I have when turning wood, I cannot get the level of
the wood to be smooth like I think I should be able to do with
the tools-before going to sanding. Even when using-what I consider a sharp skew- I end up with a surface that like it has large open pores in it.
I tried oak, walnut,maple and cocobola. I have to leave them oversize and
relent to a lot of sanding. Still don't get the finish I see on othe turners work.
I spent most of today resharpening and will try again next week.
If any experience turners live in eastern Illinois along Interstate 70 that would be willing to give lessons, please let me know.
Thanks for all your help---without this site I would really have given up
a while back.
Thanks
Ron

 

[ianjwebster]

Hi Ron,

I feel your pain. I'm still in the early stages so can't be of too much help but here is my 2c worth.

Some (open pore) woods will always do that. For woods like Oak and Walnut I 'fill' the pores with several coats of medium CA. Then use my carbide tool to 'smooth' it level followed by sandpaper.

If the wood is just tearing out rather than pores then the mantra I was told - "Sharp tools - light cuts".

I exclusively use the carbide tools on wood and acrylic. When I get close to finished diameter I rotate the tool 45 degrees (so it's resting on the corner rather than the flat edge) to use a short of sheer cut. Helps a lot.

On soft, punky or 'brittle' wood I soak in thin CA, shave a bit off, soak in thin CA shave a bit more off and so on.

At first I was getting around 1 good pen for every 8 or so runined blanks. Now it's more like 5 - 6 good pens to every 1 runied blank.

Good luck

 

[Boz]

Ron,
Your oak and walnut are pretty open grain woods. Maple is much harder had should machine to a smooth surface. I would think that practice is needed on how you hold the chisel. Sometimes the smallest changes in the angle of the presentation of the blade to the work piece can make the difference between smooth cuts and chatter and gouges. I have found that when you get off into the weeds on a blank grab some course sandpaper double stick taped to a small block of wood and sand the blank smooth. Then try again with the skew. Sometimes when you have a garfed up blank the harder you try to correct your problems the more you just add to them.
Keep working and you will find a system that works for you. I am in St. Louis which is on the other side of the state. A little far to travel for a tech session.
Good luck

 

[ctubbs]

I notice no one has mentioned the speed of your blank. I always try to turn as fast as I feel safe. Slow = more catches and tare out. Faster will offer less chance for the tool to grab chunks and give a smoother surface, but nothing will improve the surface like sharp tools and good form. The wood you are using will also make huge differences in the smoothness of the surface.

You mention using a skew. It can be very unforgiving but can also produce glass smooth finish if well sharpened and applied correctly. I recommend that you find some FOG (found on the ground) wood and practice turning that until you get the feel of your skew, much cheaper than burning through expensive blanks. You are at the right place for asking questions. The Old Hats here are a wealth of great info. They have been very helpful in my quest. Do not give up, grab some wood and a tool and make shavings.

Charles

 

[Phillikl]

An old timer once told me: "Turning wood on a lathe is like shaving. You can shave with a sharp razor or a dull razor, just depends on your pain tolerance." At this point I hand him my "thought" to be sharp skew, And with 1 small eye, he responded with "You must like pain!"

While i do enjoy my carbides, I notice a false sense of security with their "sharpness". When I start to get the "chatter" effect, I take a few minutes to meditate with the wetstone. Seems to put everything back to normal.

On a side note, some of the world renoun turners started off as tool sharpeners.

 

[jcm71]

Ron,
+1 on Charles' comment above on speed. The faster the better. I turn at 3600 RPM, and I'm sure there are some out there who turn at even faster speed.
A couple of questions about your technique/methods. When you sand, what grits do you use? Do you stop the lathe and sand length wise for each grit? Regardless, with some woods you are still going to have some pores. When sanding, save your sawdust. Put in on a small piece of sandpaper and make a slurry using thin CA, and then apply the slurry to your spinning blank. Work fast here. Let dry and start your sanding process again.

Good luck

John

 

[leehljp]

Russ Fairfield, one whom has gone on but well remembered as a pioneer in the pen field, and one whom (I think) came from a wood turning background wrote something as to which tool (skew or scraper) for which woods.

See that here in the 7th post down:
http://www.penturners.org/forum/f28/requires-least-sanding-46171/#post842549


In addition to which tool to use, what Boz wrote was the first thing that came to my mind. In general, I have noticed here that while woodturners come with a lot of skill, and experience, the "micro" (compariably) work of pen turning requires different thinking and techniques.

As mentioned above, on open grained wood that isn't that noticeable with larger bowls will really show up as coarse on pens. I am not taking the time to be anywhere near accurate but figuratively speaking: Pens are miniscule in size and the speed of 2000 rpm is only as fast as 400 rpm on a bowl. I have noticed over the years that bowl turners come here and bring the concept of "slow". Doesn't work well with pens!

On open grained woods, you might want to put one initial coat of thin CA but follow with a couple of coats of medium or thick (after it is turned down to size) and let the medium or thick set up and cure. I allow 10 to 30 minutes depending on the ambient temp.

One last bit of information is that you do what I usually do and I have just come to accept that it is best for me - sand down. I do segmenting often and for me, I get the best outcome most of the time from "sanding down" from the last mm. This may be too much for some but I have less problems in the long run doing this - except with some segments with metal, which has finishing problems if sand paper is used. Sanding aluminum or brass segments, or bloodwood with holly or black/ebony with holly or maple - sanding causes problems with the finish that is difficult but not impossible to overcome.