antekboodzik
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Yet more making pegs
Hi,
I decided to make another renaissance lute for myself. This time I have started with... making pegs, as it is the most complicated and time engaging
task for me. I have very little experience with woodturning, and nobody to ask or follow, so here are few questions I would like to ask. And several
interesting threads here are devoid of pictures.
Now I need 13 pegs for a seven course instruments + a few spares. For that I prepared another simple lathe (a poor man's lathe). It is also designed
to be run with handdrill, but I found neat beared spindle (or however it is called), and use it with drill chuck and simple spur. It is the best part
of this setup, it turns perfectly without any loose or off-center. It has also the advantage of possibility to hold almost finished peg by its shaft
to master the peghead and end pip. Whole lathe setup is powered with 180W 230V motor. Also, I took plenty of chisels and gouges, including a
hobby-quality set of three woodturning tools - a skew, a straight chisel and a parting tool (actually not shown on the picture).
So here are few first pegs in european Cherry Wood... But only two or three are consistient in diameter and pretty, the rest vary with dimensions and
shape. Now I look jealously on videos on Youtube, where wooden pegs are made perfect in shape in a matter of minutes, and I have several questions.
1. This motor has 1400RPM. With slightly smaller diameter of wheel of the lathe it should have about 1700 - 1900 RPMs. Isn't it too low speed for such
a small work?
2. Has anybody tried to use for pegmaking this stuff?
http://www.proxxontools.com/store/pc/viewPrd.asp?idproduct=77
it has spedd up to 5kRPM. Would it be good for peg making?
3. I can make peg (at least one as presented) in 30-40 min. Is it too much? Shouldn' this work take less time?
4. I found it very hard to use "parting tools" - the real one I have, another one I made from tool blank and few small chisels. This kind of cut
produces a lot of noise, isn't effective and the lathe and a worked piece got vibrations resulting in very uneven surface. Why? Probably the tool rest
isn't stable enough.
5. I got an idea of 'dipping" pegheads in shellac, to provide simple finish, and stain it against moisture from fingers and dirt. Is it good?
6. Maybe it is not so easy work and require a lot of craftmanship? Or better tools, or maybe I am too Ham-fisted 
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antekboodzik
Oud Junkie
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I forgot to add, that I found that the belt is set to be rather loose. If I tried to tighten it (or put another one, shorther) it all resulted in
strange vibrations of whole setup caused by free parts of belt moving just like the string vibrate. Now there are no vibrations when simply run
without cutting, but I think there is possibility of belt "slippery", causing short stops of rotation and bad performance. Maybe this belt isn't best
one, or shall I tighten it really hard (but one wheel is made from plastic)?
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jdowning
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You will find some information/ideas about peg turning - with pictures here:
http://www.mikeouds.com/messageboard/viewthread.php?tid=6778&pa...
You have made a number of pegs with your current lathe set up so lathe speed is not an issue although for small diameter work like peg turning the
higher the speed the better.
For small size work your lathe needs to be free of looseness and vibration so make sure the lathe and components are securely bolted down to a solid
bench top. Replace the plastic pulley with a metal one and change the drive belt if it is slipping under adequate tension.
Do not try to use a parting off tool for small diameter work - just cut the finished peg free with a saw - the lathe being stationary.
You will need to use small size detail turning chisels for free hand lathe turning (make your own). Use small gouges for roughing pegs down to size
and then finish with scraper chisels. These are turning chisels sharpened in the usual way but then formed to a slight hook by burnishing (like a
bench scraper blade) - or by grinding the tool bevel and leaving a burr on the cutting edge without further honing. Scraper chisels are used with the
hook or burr upright with the work turning towards you (of course!). These tools produce fine shavings.
Don't varnish your pegs with shellac - it will soon wear off. Staining pegs black is traditional and OK - but that too will eventually wear away with
use.
With experience you should be able to make a finished peg in 10 minutes or less - but what's the rush!? Slight variations in peg shank diameter do not
matter as an accurate, consistent taper will be cut later with a peg shaper. Slight variations in the peg head shape matter even less - they are a
sign of a hand made peg variations that likely no one will ever notice. Make a template to check accuracy of your work.
Good progress so far - good luck!
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antekboodzik
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Thank you very much for your support and encouragement. There are yet 8 pegs
However, let me ask some more questions. On this video:
http://www.youtube.com/watch?v=CoDbHF1mBek
the maker is using straight chisels (?) and cut at right angle to the peg. It has never worked for me, making a lot of noise (like squeaking), and
causing vibrations. I was trying doing the same thing with narrower parting tools - it was only partial solution. Now I am using gouges for roughing
and skew chisel (or wide straight chisel holding it at 45 degree angle), and this cut rather cuts wood than scrapes it.
By the way - what is the sealing used at the end of this video?
Again, you are using tool support to hold profile cutters. I can't imagine how it works. At later stage of turning peg heads the line of contact
between tool edge and peg is quite long - how does it even work, being effective and not producing chatters, vibrations. and a lot of heat?
Also I was doing few trials with... bow lathe, but again, my tools must be inapropriate, because I was able to hardly remove any material only, and
producing a peg this way would take me probably a week or so.
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jdowning
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The straight chisel being used is a scraper chisel, The term scraper is a misnomer as - like a cabinet 'scraper' it does not scrape but cuts a fine
shaving due to the burr formed on the cutting edge. The burr on turning chisels is often formed on a grinding wheel - the burr forming naturally as
the edge is ground.
Using a skew chisel is tricky particularly on small work and not necessary when making pegs.
My profile cutters are also scraper chisels and they do work both in bringing the work roughly down to size as well as finishing to an exact profile.
Material is removed little by little using several passes of the tool.
At the end of the video the worker appears to be simply polishing/burnishing the peg with a cloth (mildly abrasive) - no sealer appears to be
applied?
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antekboodzik
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That's it! Thanks
I found that if I set the grinder to rotate backwards (an improvised one, powered by cordless drill), and then grind my tools at greater angle (not 30
like chisels, rather 70-80), it produces nice burr on the cutting side of the tool. I managed to do only few trials, but it is quite nice improvement,
both in speed and accuracy of work. This trick makes the tool to produce exactly looking shavings as on the mentioned video. It works also for skew
chisel (at least for one side of it), even using it "as normal" skew (the cut only near lower tip). But after some time of using the burr goes away,
so I repeat grinding... And sometimes the worked piece needs rather heavy sanding to wipe long, narrow marks after the tool has "chipped" more
shavings.
How do you raise burr on more complicated turning tools?
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jdowning
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Scraper turning chisels are usually always relatively thick and ground with a steep bevel to better with stand the greater forces (compared to a
skewed chisel cut).
There are three ways to sharpen them:
A - grind the chisel to the required bevel - say 80° and remove the grinding burr by honing to a sharp cutting edge.
B - repeat A above but use a steel burnisher to raise a hooked edge (like for a cabinet scraper). This is the most effective scraper edge but only
applies to straight edged or rounded nose chisels.
C - grind the bevel and leave the slight burr on the cutting edge. Less efficient than B.
Edge A has the least efficient, slower cutting action but does work if properly honed. This is the edge applicable to complex chisel shapes like the
forming tools that I use for shaping pegs in a machinists lathe.
Lee Valley of Ottawa sell a scraper chisel burnishing rig that is convenient for high speed tool steel chisels that require some force to raise a
burnished edge - but it can be done freehand.
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antekboodzik
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Thanks for comprehensive explanation. With that I have prepared one tool, which was an HSS tool blank with a burr raised with holding end of
hi-quality drill bit. This tool did most of the job. My wood turning is still far from beeing satisfactinery, however, with your explanation turning
pegs became a little easier and predictable, less frustrating and in the end less wood was wasted. And here is the final result
I decided to "dip" every peghead in shellac. I let it to soak for a minute or more, so the shellac has penetrated wood quite deep and this coat is not
so easy to be removed, even with sandpaper, so it should last for long.
But how can I "buff" pegheads to high gloss? I read somewhere that buffing wheels are used - but which wheels and with a polising compound or without
it? How to prevent polishing compound from contaminating shanks? Also, how with waxing pegs? What are waxes used in instrument making? Is this
technique used for pre-sealed wood or not, just on "bare" wood? I read also about waxing instrument tops - how it is done and for what? Isn't wax
"damping" the sound, as it is somehow oily?
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