cross cut zebra wood

[RogerH]

Hi everyone.

I purchased some beautiful, cross cut zebra wood on here, and have been having a heck of time turning it (first time for me).

I have turned other stuff that can be tricky like burls, and segmented blanks, and other cross cut blanks, and I was able to make those work.

I am batting .000 with this stuff. I have tried twice, and ruined 3 out of four blanks. Only one satisfactory tube, and it is beautiful stuff when finished.

My chisels are extremely sharp-I sharpened both my skew and bowl gouge just before I tried to turn them-and no luck with either. I am getting blow outs at the ends of tubes when I get to a thickness of 1/8 to 1/4 of the bushing, no matter which direction I start from.

Any suggestions?

Thx

Roger

 

[Drstrangefart]

Keep soaking it with thin CA as you go? That's what I'd try.

 

[RogerH]

I think you are right. I put ca around it to start after I had blow out after I roughed it round, but then I got lazy and didn't reapply every few passes, and so then I got the blow-outs when I was down to 1/8-1/4 of the finished diameter.

Thx for reminding me. I'm also gonna put CA at the end of the blank where it intersects the bushings to try to eliminate the blowout.

 

[Drstrangefart]

I think you are right. I put ca around it to start after I had blow out after I roughed it round, but then I got lazy and didn't reapply every few passes, and so then I got the blow-outs when I was down to 1/8-1/4 of the finished diameter.

Thx for reminding me. I'm also gonna put CA at the end of the blank where it intersects the bushings to try to eliminate the blowout.

Cool. Just remember to wax the bejeezus out of the bushings. I have far worse sticking than when I can run without stabilizing.

 

[jbswearingen]

What speed are you turning?

 

[Justturnin]

I know X-cut can be tricky. I actually use a 3/8" bowl gouge to cut mine w/ the wings swept to the handle (not really but they go way back) and then I remove a lot of the unecessary steel from under to creat a micro bevel. Then I take light, feather light cuts. When I get close I will turn it and use as a neg edge scrapper (straight across no bevel rubbing) and just shave off little whisps of wood. And when I start to get close I usually chicken out and get the 60grit gouge to finish.

 

[RogerH]

Brad-about 1500 rpm.

 

[RogerH]

Allan-great idea. I always just let the CA coat the bushings when I do a CA finish, and then use the parting tool to scrape it off, and score a line between the bushing and end of the blank when I am ready to take the blanks off the lathe. Bees wax is a heck of a lot simpler, and I'm sure faster too! Thx for the tip.

 

[RogerH]

Chris-wow you are WAY more sophisticated on your chisel grinds than I know how to do. I am just happy (and a little proud of myself) that I can keep my chisels super sharp bc I got a slow speed grinder and a sharpening jig a couple of months ago !

What a great idea to put a little back bevel on the underside of the bowl gouge. I think I'm to chicken to try it now, but maybe some day. I can and will work the wings back on it, to prevent snags.

Thx for the suggestions. It is BEAUTIFUL wood.

 

[jbswearingen]

Roger--

Try higher speeds. Make sure you're wearing your face shield!

 

[RogerH]

Thx, Brad.

(That will be an incentive to put on the new belt I have for my reeves drive. It has been slipping for about a month, and I've just put up with it !)

 

[bitshird]

Roger, also try turning from both ends to the middle, with X cut Zebra you are dealing with many many layers of wood, a lot of times you will have better luck turning the blank to a reasonable size, then start working from the ends to the middle, you will notice that most of the blow outs happen when you are coming up to the ends, and also the CA helps as well.

 

[Drstrangefart]

Allan-great idea. I always just let the CA coat the bushings when I do a CA finish, and then use the parting tool to scrape it off, and score a line between the bushing and end of the blank when I am ready to take the blanks off the lathe. Bees wax is a heck of a lot simpler, and I'm sure faster too! Thx for the tip.

I'm pretty sure there will still be a bit of cleanup, but the barrels SHOULDN'T be bonded to the bushings hard enough to tear chunks of wood off when you go to separate them. There's a reason you haven't seen me post a pen made out of the cedar from Dad's deck. Sooner or later I'll try again and apply wax quite liberally.

 

[RogerH]

Thx, Ken.

 

[xxShadowxx]

for some of the hardest to turn stuff, i resort to sand paper if soft material, or diamond blocks for harder stuff - soft stuff gets eaten right through, and almost never fails, hard stuff takes a while, but vs failing i find the time acceptable tradeoff

be warned, mad dust maker there :biggrin:

 

[patmurris]

After blowing a few cross cut woods, heavily spalted or wormy stuff, or very fragile or porous blanks i now do the following:

- if the wood is really porous, wormy or too light to be trusted i soak the blank with thin CA before drilling
- after drilling, i run thin CA inside the hole and let dry
- i run a file through the hole until the tube easily slides through
- i heavily scratch the tube with 40 grit then clean it up with a wet cloth then wipe it dry.
- i glue the tube with epoxy, not CA
- i roughly round the blank on a sanding belt or disk before turning
- i apply thin CA on the blank ends
- i keep soaking the wood with thin CA several times while turning
- i use a sharp gouge and take light passes from each end toward the center
- once turned, i apply a couple layers of thin CA as a sealer before sanding

...with all those precautions, i can now turn pretty much anything!

Note: i tried sanding instead of turning, but it can quickly make your barrel out of round...

 

[Lenny]

After blowing a few cross cut woods, heavily spalted or wormy stuff, or very fragile or porous blanks i now do the following:

- if the wood is really porous, wormy or too light to be trusted i soak the blank with thin CA before drilling
- after drilling, i run thin CA inside the hole and let dry
- i run a file through the hole until the tube easily slides through
- i heavily scratch the tube with 40 grit then clean it up with a wet cloth then wipe it dry.
- i glue the tube with epoxy, not CA
- i roughly round the blank on a sanding belt or disk before turning
- i apply thin CA on the blank ends
- i keep soaking the wood with thin CA several times while turning
- i use a sharp gouge and take light passes from each end toward the center
- once turned, i apply a couple layers of thin CA as a sealer before sanding

...with all those precautions, i can now turn pretty much anything!

Note: i tried sanding instead of turning, but it can quickly make your barrel out of round...

What Pat said! That was my thought as well. Good luck with the next one!
They can be a real challenge but are well worth it in the end!

 

[Sabaharr]

Turn slower and take small bites. I know, I am impatient too, but it should help with the addition of a good CA bath every few passes.

 

[AultMan]

Easy answer

Put your tools down and get some 40-grit. = 100% success rate.

 

[RogerH]

THANK-YOU to everyone, but particularly to Pat, for all the advice.

RE the use of 40 grit-I have tried that, and as Pat said, I often end up with something out of round.

CA soaking, reverse coating the inside of the blank, using epoxy on the tube, and more thin CA as I turn with VERY sharp tools, seems to the be consensus of how to do it. Again, I truly thank you guys for all the ideas !!

 

[AultMan]

sandpaper

If you wrap the sand paper all the way around you can avoid the out of round issue. I do it all the time.

 

[glycerine]

What tools are you using? Have you tried a scraper after turning it round?

 

[RogerH]

John: Thx for the idea of putting the sandpaper all the around the blank-those are just the sort of inventive ideas I come to the site for !

Jeremy: I am using primarily Sorby chisels. My favorite is their spindle gouge, which I used for my first try on the cross-cut zebra. When that didn't work, I went to my Sorby skew. Both are very sharp-I have a slow speed grinder and jig and so I sharpened before I began work.

Thx again to everybody who posted.

 

[glycerine]

John: Thx for the idea of putting the sandpaper all the around the blank-those are just the sort of inventive ideas I come to the site for !

Jeremy: I am using primarily Sorby chisels. My favorite is their spindle gouge, which I used for my first try on the cross-cut zebra. When that didn't work, I went to my Sorby skew. Both are very sharp-I have a slow speed grinder and jig and so I sharpened before I began work.

Thx again to everybody who posted.

How are you holding the skew? Are you using it like a skew or like a scraper?

 

[sbarton22]

what is this kind of pen supposed to look like?

 

[okiebugg]

crosscut blanks

FWIW, almost everything I turn is crosscut. I like the grain characteristics and chatoyance you get from a project.

I do about 1000 RPM +/- 500RPM

Ultra sharp 1/4 to 3/8 spindle gouge and extremely light cuts when roughing. I find that the skew puts too much lateral pressure on the blanks and may cause internal forces to mini-crack the wood. Once I get the square edges cut mostly off of the blank, I switch to a Pen Pro to smooth out the blank at this stage and look for cracks. Again with woods like CC Zebra, Bocote, Padauk and others, I go back to the gouge and light cuts, take it down close to the finished product.

The one thing you must focus on are the corners/ends of each blank. If you use a skew or a scraper, you must start at the outside edge of the ends and it works pretty well with the gouge. The corner/ends are most likely to blow if you go from the center of the blank to the outside. With these grainy woods and crosscut woods light cuts are the simple answer.

Again for what its worth.

 

[srf1114]

Man Crosscut Zebrawood is my bane.
First time I did it it went flawlessly, so of course I felt piece of cake. Next one had a rescued blowout. third one split two weeks after completion.

Then doing my latest one, Majestic FP. the Body turned beautifully, but went through 5 different blanks for the cap. Even the successful cap had a blow out but I was able to rescue that one. Turned out awesome, but took several months of frustration.