End Grain Maple Bowl - Tips?

[howlingbaboon]

Hi All

I tried to turn my first end grain bowl last night and encountered a few difficulties and wondered if you good folk could offer me some tips. The wood is maple, slightly spalted, and was from a tree that was felled recently but died at some point over the winter. As I turned it, I seemed to get a lot of tear out. After an enormous amount of sanding, I managed to get the outside really smooth and was very happy with it.

The inside is where I encountered the first problems. The first, an odd German chap repetitively playing Spice Girls and Whitney Houston full blast (don't ask? ), probably caused the others. I got a couple of catches and had to make it a bit thinner than I was planning. I tried my best to get the torn grain smooth using a round nosed scraper and a pair of sorby ring scrapers (one of them caused a catch). Again it was a nightmare to sand smooth, starting on 120,180,240 etc. There were few rings of tool marks that I just couldn't shift. They didn't look too bad however until I waxed and used fine wire wool. This left the tool marks a dark grey colour and seems to ruin what would otherwise be a nice grain pattern. I've used wax before without that happening so I'm not sure what caused it.

I didn't spend much time on the foot (as you can see). The problem I'm worried about with this is those radial cracks which appeared while It was in the chuck. Did they appear because I cranked it to tight (old sorby precision chuck) or because the bottom of the bowl contains the pith? (off centre). Do you think it will keep cracking now?

Any tips you have would be most appreciated

[fuzzyturns]

Well, there are so many things that would need to be said here,so I will compile them into one overriding comment: book yourself a day or two of tuition with a professional wood turner. On this forum, one of the best is George Foweraker (GBF), but since I don't know where you are, he may be a little far away.
Join a local club, they will have experienced members that can give you tips and pointers.

[howlingbaboon]

Wow, that bad? I'm based in Lancaster. Here's where I'm up to so far if it helps with advice:

I've had an introductory session with the chap who donated the lathe to our makerspace.  Most of what I've learned so far has been from online research and videos (but quite a lot of those). So far I've done some spindle work, chess pieces, candle sticks, a couple of types of spiral. After a couple of failed attempts with some old wormy Lime (1st I delved too deep and found bottom, 2nd foot cracked and came off lathe) , I recently turned a dry small Beech bowl and 3 large green alder bowls ,one with a natural edge, all face-grain (now bagged with shavings). I'm happy with those, so far so good. fingers crossed!

Sorry I should have given a bit more detail about my experience (or lack of ) I'm sure you are right, I could use more lessons. In the meantime, any tips for my next venture to the lathe?

[Les Symonds]

Frankly, there are so many issues which may have caused your bowl to fail, that you could write a whole book about it......indeed, there are many books out there explaining all this to you.
Principally, I suspect that you are trying to run before you've learnt to walk. Any green-turned bowl is going to undergo massive changes in the dynamics of the stresses built up within the timber. In its wet and natural state, the forces are held in balance, but spinning it at speed causes a high degree of moisture loss. Cutting 90% of the volume away as shavings just adds to the sudden release of stresses. There are two basic guidelines that you need to follow (and dozens of others that might help)....

• Until you're used to this sort of work, try to avoid leaving the pith intact. Most of the cracks will be radial cracks emanating from the pith. If you remove the pith you lessen, but not negate, the likelihood of cracking
• Turn the timber to an even thickness throughout. This means that the inside profile will follow the outside profile, quite precisely. You've told us that you didn't pay much attention to the foot....big mistake. Leaving the bowl bottom-heavy, as yours is, and leaving a mass of timber at the foot, both result in uneven releases of the stress in the timber. It was almost inevitable that your bowl was going to crack.

As fuzzyturns said....get yourself some training and as for your next venture on the lathe, get some dry wood and practice making a bowl with an even thickness throughout.
Les

[Bryan Milham]

Les and Fuzzy have hit all the important facts. Green wood is a joy to turn but you do need to know how to handle it.

Can I suggest you use green wood as practice wood and don't worry too much about what happens when it come off the lathe. Just learn your tool control form it, it's cheaper than the dry stuff you have to buy.

[howlingbaboon]

Thanks for the advice guys. I've a garage full of chunky green logs now. Plenty to practice on. Here's one of the larger Alder bowls I turned. As I knew this to be green, I paid much more attention to getting it even thickness using the calipers. This brings me to another couple of questions.

Does dry wood also need to be even thickness or can you get more creative with shaping that? Is there still risk of cracking?
I've mounted my bowls so far with a dovetailed mortice. I've had to allow a bit more thickness in the base to take this into account, is that the right way to go about it? The last large bowl I did, I let the inside bottom bulge up a little in the middle to try and take account of it.

Any clues on my original question about the grey marks? I guessing its to do with preventing tear out or dealing with it. As I say it was my first go at an end-grain bowl so a few end-grain pointers would be great.

[howlingbaboon]

I just watched this series of demos by Mark Silay. Feel I learned a lot. Think I'll be coming back to them as there was so much for me to learn.

https://www.youtube.com/watch?v=A9cLCrjOZYY

[seventhdevil]

go to ebay and buy a second hand ringtool that someone used once and gave up because they didn't know how to use one. they are intended for endgrain use and will be perfect for you if that's what you wish to make.

[howlingbaboon]

Funnily enough, we were donated 2 of them about a month ago. I've been struggling to find any videos on how to use them properly(searches often find captive ring stuff instead). I've had some success but a few careless catches. Do you know how they are sharpened? Was wondering whether a morticer chisel sharpening bit might work...?

[bodrighywood]

go to ebay and buy a second hand ringtool

My favourite tool for taking the wood out at speed. Not difficult to use. Just don't try to sharpen on the wheel, use a diamond sharpener.

Pete

[howlingbaboon]

I'm learning here! So they're not just for finishing then? Do you mean a diamond stone like this one?

http://www.axminster.co.uk/diamond-cone-mortice-chisel-sharpener-502458?gclid=Cj0KEQjww7zHBRCToPSj_c_WjZIBEiQAj8il5NDkFUTEILTTdP2aXQ8ha20vuxhnxfPFCluSpH8R0hMaAjZg8P8HAQ

Or do you sharpen these by hand?

[bodrighywood]

I'm learning here! So they're not just for finishing then? Do you mean a diamond stone like this one?

http://www.axminster.co.uk/diamond-cone-mortice-chisel-sharpener-502458?gclid=Cj0KEQjww7zHBRCToPSj_c_WjZIBEiQAj8il5NDkFUTEILTTdP2aXQ8ha20vuxhnxfPFCluSpH8R0hMaAjZg8P8HAQ

Or do you sharpen these by hand?

No, this sort of thing.

Pete

[edbanger]

Hi Howlingbaboon

Please Do Not and I repeat Do Not attempt to turn a bowl like Mark Silay I've just watched his video and these are advanced cuts with tools and actions that will cause you problems.

As a beginner you would never use a tool without one had supporting the tool on to the tool rest at all times.

I turned it off when I saw his Special grind on the bowl gouge this tool looked dangerous!!!

Please book a lesson here's a list of professional woodturners from the RPT site in your area http://www.registerofprofessionalturners.co.uk/county/lancashire/ and here is The AWGB site, but I can not see anyone close to you on the map https://www.awgb.co.uk/awgb-tutors-map/

This is the problem with youtube when your new to turning you don't know who or what you are watching. Also youtube will never replace having lessons as the person demonstrating on the video can not see how you are interpenetrating the instructions so there's not way to correct the person watching.

I've uploaded a few video's on basic turning safely! you can find them by searching Olivers Woodturning. I'm not for a second claiming that my ways are the best and only ways to turn, there are a lot of better woodturners than me but they are safe and will get you started if you can't afford lessons.

Also join a club you can learn a lot for free or very little money the AWGB clubs are listed here https://www.awgb.co.uk/club-map/ the closes to you seems to be Preston a google search for woodturning clubs might bring up other clubs closer that are nothing to do with The AWGB.

Ed


 

[Les Symonds]

I'm with Ed on this.....the dangers of learning through videos on YouTube is well documented. As Ed says, Mark Silay's practice of turning one-handed is not for beginners: indeed, if you look closely you'll see that he has a few catches and skips of the gouge when he is doing it. I've spent most of my life in and around teaching and I have always been of the belief that you should never demonstrate any technique that you would not want a student to use. OK....I accept that perhaps he was turning single handed so as to give a better view of the cutting edge to his students, but the danger is that students will often want to emulate the skills of the demonstrator. A fact that is confirmed here, in this thread.
I learnt the hard way, to turn. I didn't have any tuition and I watched a few videos and read a few books. That taught me a myriad of bad practices which I am now having to drop and replace with sound techniques. If I had my time over again, I would have gone to a professional for tutoring.
Les

[howlingbaboon]

Don't worry guys, I'm no fool and am not about to ever try anything one handed and understand that it was a somewhat cocky and dangerous means of making his point about controlling most of the cut with the rear hand and body at the pace the tool wants to cut.  I can take the point without feeling the need to try his dangerous demo. I do appreciate your concern however. Health issues prevent me from traveling much or committing to specific dates for classes etc and as you've pointed out, there doesn't seem to be a local club or instructor. I have had some teaching from 3 real people so far though so am not completely flying solo here. I feel like I'm progressing safely and steadily and books videos and forum tips are just handy hints and slight adjustments at this stage. As a teacher and outdoor instructor I am quite familiar with assessing and avoiding risks but also enjoy the adventure of self learning. Had the odd catch but who hasn't?