Spokeshave chatter
- This topic has 16 replies, 7 voices, and was last updated 1 year, 4 months ago by
.
-
Posts
-
Confession time: Even having built some moderately involved things, I still struggle with what is usually considered one of the simplest tools: Spokeshaves. The problem is chatter, _especially_ as the work becomes wide, like cleaning and fairing the curve on a 2 1/2″ wide back support for a chair. Like all things, this will likely end up being a sharpening problem, but I can get my planes sharp enough to work in figured woods. I’m wondering if others struggle with this and what they’ve done to overcome it.
Make sure the iron is sharp, skew it across the work, set it to take a fine cut, sharpen it up nice.
Maybe make sure the surface where the blade sits is flat.
By the way, if you feel you have good luck avoiding chatter, especially on wide work, please let me know whether you sharpen your blade straight across or do you put a radius across the width of the blade? Do you tend to get shavings that are just, say, 3/4″ wide, or are yours wider? Do you use Paul’s sharpening method, or something else?
Only times I have this issue are when the blade isn’t sharp or the blade is protruding too far.
I’ve found grain direction is also important, are you perhaps taking too big a cut against the grain?
It’s essential, really essential, that the edge is sharp….. that’s already been pointed out.
Whilst the ‘mouth’ gap may not be as important as it is with, say, the finishing cuts on a plane, it can be an influence on the thickness of the shave – and ultimately your control of the tool. Perhaps some experimenting with adjusting the gap with shims or spacers under the blade may help to eliminate the problems. In shaping, many repeated thinner cuts give better hand control than one great slice.
Another very old trick with shaves like this was to arrange the blade so that it was slightly skewed on its bed. This allowed you to take fine shavings at one side, moving over to thicker cuts on the other side where you need to get more meat off in one stroke.
As with everything we do, it gets better with practice.
Good luck.
If you’re using something like a Stanley 151 and working on flat material wider than the shave, how wide (not thick) would your shaving be? Do you sharpen the blade straight across, or do you use a small camber so that you only get a narrower shaving?
Ed, thanks for the reply…. if I understand you fully, you are shaving a flat board wider than the shave’s blade?
If that’s the case, then I would not use a spoke-shave, it is a job for a standard plane if you want a flat surface. A spoke-shave is intended for shaping rounded or curved sections, not as a plane substitute. As far as the spoke-shave blade is concerned, I don’t see any advantage in sharpening it to a slight curve as you would with a standard plane – in use it will always be wider than the work that it’s cutting and the corners will never dig in.
To attack small areas on a flat board, you may find a card scraper or Stanley/Record No: 80 more use; these are intended to be slightly curved in their application, producing a very shallow concave cut.
Good luck
PS…. apologies, I have just re-read your original question and it appears that you are shaping the curved back comb or lower rail on a chair-back, correct?
If this is the case – and this is my method – I’d use the shave to form and curves or chamfers on the narrow edges, but as the flat surfaces, front and back are respectively concave and convex, I would go to a heavily set scraper to form the shape and get the thicker shaves off, refining the set for finer shavings as you get close to the end-shape.
You can use card scrapers, but to avoid bending the thin metal, try clamping two or three together between two pieces of scrap wood and drawing it downwards from each side to meet in the the middle. A bit laborious, but it will do the job.
However, the absolutely ideal tool for this shaping job on chair-back components is not available in the UK, never exported here – though easy to get second-hand if you are in the US – and it is the Stanley No: 82 scraper. Look it up on line. It’s perfect for this job. So, Ed, if you are in the States, get one!
Good luck
The work is flat in its width, but curved (concave) in its length. It’s the sort of thing you’d think you’d want a compass plane for. So, the work is wider than the shave, but curved. Think of the upper and lower supports on the back of Paul’s rocker, the pieces that all the slats go into. In fact, I looked at Paul’s video in which he is fairing the curves on those supports and noticed that he is only getting narrow shavings, which is what made me wonder if he has sharpened a camber across the width.
@HOWARDINWALES
Somehow, I didn’t see the second half of your reply. When you say a “heavily set scraper” do you mean like a #80? So, you’d let the blade protrude a fair bit to deal with the concave arc?Ed, if you are looking at the various rockers on this site, I would suspect that the concave back rail or comb sections are achieved with a spoke-shave with a slightly curved base. The older classic makers used to offer both variants, flat and curved bases, which may account for your ‘chatter’ if your base is flat, also amplified if the cut angle is straight rather than skewed. The blade would then need to be extended beyond the sole to overcome the curve. The convex backs will work as normal with a flat base.
By ‘heavily set’ I mean to say that the angle of the ‘hook’ on the edge of the scraper blade is well pronounced to give a deeper cut.
When I mentioned the Stanly No: 82, I did not intend to confuse it with the No: 80 pattern which is a different tool entirely. There are plenty of pictures of both on the internet. Sadly, Stanley hasn’t made it since the 1950s, though Veritas brought out something similar….A couple things have helped. First, I’ve stopped using the knurled adjusters on the 151. They are too coarse. Instead, I am advancing the blade with them on a piece of scrap until the blade isn’t quite cutting. From there, I tap with a hammer to set the depth of cut. This is giving me far more control and is allowing a finer shaving. Second, I’m tightening down the blade significantly more than before. To some extent, I use the hammer to advance the blade and the knurled knobs to bring it back if I go too far, then relax the knurled knobs (take advantage of the backlash) so that tapping with the hammer will work.
I also have a #52 and I think it works better than the 151. I can tap with a hammer, as just described, but I can also tighten and loosen the thumbscew which gives very fine control of the depth, although over a limited range.
The problem isn’t entirely gone, but these things have helped. I’ve also played with putting a camber across the blade for working on wide stock, and I think that may help a bit. Not sure yet.
One thing that can cause chatter is if the bed the iron sits on isn’t flat or the cap iron from edge isn’t flat.
You might have to file the bed or get the iron front edge flat.In this post Paul shows how to restore the 151 variants and uses a medium diamond paddle to take off the high spots.
https://paulsellers.com/2014/07/restoring-a-151-record-marples-or-stanley-spokeshave/
@LORENZOJOSE That’s a good point. I had done it when first setting up the tools, but I redid it yesterday as well. I found a piece of 100 grit paper glued to a thin paddle to be ideal because it cuts quickly. So, that had already been done.
@HOWARDINWALES Regarding the scrapers, would you go directly from the bandsaw to scrapers without anything in between? No edge tool or rasp?
- You must be logged in to reply to this topic.
