White Rotary 41 - Several Interesting Differences
This is my first post on the Quilting Board. I've come across a machine that does things a little differently than most that I've seen. I am hoping that some of the members here might have some thoughts on, or even better, some experience with this particular machine.
The machine is a White Rotary 41, made in the late 1930s I believe. Its not exactly pretty, it has a lot of period styling, but it seems like a very rugged and durable machine.
It has a black wrinkle finish, probably very resilient to dings and scratches. I'm thinking that it might be about the most difficult kind of surface to clean, though. I've been experimenting with various methods to clean it. So far I have only done a once-over much needed cleanup of many years of surface grunge. Just good enough to take these pictures. More needs to be done.
I learn something from each machine that I study. I'm learning more than usual with this one. The White Rotary seems different in several respects, some almost unnoticeable, some much more obvious. I'll try to go on order of increasing significance.
Only a visual matter, one of the things I really like is the T-shaped bobbin cover plate. No practical reason - I just like its look.
(White Rotary 41 - Front View)
[ATTACH=CONFIG]518221[/ATTACH]
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Bobbin Winder - An eye-catching chrome bobbin winder, along with the pancake handwheel, contribute to the period styling of the machine. It looks like the 1930s. There is a contoured bar that extends upwards with a roller wheel to guide the thread to the bobbin. On the bottom of the winder is a curved, ball tipped handle.
Needle Plate Area - This area is raised very slightly from the main surface level of the bed. It seems like this might be nice for sewing. At the very least, I think it has a pleasing look.
(Bobbin Winder) (Needle Plate Area)
[ATTACH=CONFIG]518222[/ATTACH]
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Drive Method - Really not that unusual, but the White Rotary is a direct drive machine. The direct drive turns the handwheel in the opposite direction from belt driven operation. For those used to the top-of-handwheel-toward-you standard, it might take some getting used to. Also, since the pancake handwheel has no pulley, it would require a different handwheel to ever be used with a treadle.
The rubber drive wheel on the motor could probably use replacement.
(Direct Drive)
[ATTACH=CONFIG]518223[/ATTACH]
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Clutch or Stop-Motion - When the clutch knob is removed, it exposes some unusual components, most notably three ball bearings in a ring carrier. I was fortunate enough to have read about these ball bearings somewhere and knew of them in advance. It is best to disassemble this with as close to a handwheel-up orientation as possible, so that the ball bearings don't fall out and get away from you.
The clutch assembly may be seen with the clutch knob removed. First the 3 ball bearings need to be removed, then the ball bearing carrier, then the clutch washer. After this, the handwheel can be removed.
It has the normal clutch washer, but with only one tab. The clutch or stop-motion knob turns almost a whole turn, in tightening and loosening, instead of the more common 120 degree range. The ball bearings give it a really smooth feel at the point of tightening. The ball bearings are each 0.187 inches in diameter.
(Handwheel Up) (Knob Removed) (Clutch Parts)
[ATTACH=CONFIG]518224[/ATTACH]
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Tension Control - Most tension mechanisms I've seen are basically built on a threaded rod, having two saucer-shaped disks, with a spring and adjustable knob or knurled nut .
The White Rotary 41 has a unique oval-shaped tension control assembly located on the faceplate area of the machine. Until I can get a manual, I'm stumped as to how to even thread it properly.
There is a tension adjustment knob on the front of the machine. The mechanism is hidden inside and I haven't been able to see it yet, which brings me to something else.
Most machines have a removable cover plate, or have a door which opens to expose the needle and presser bars. The White Rotary 41 has an end cap assembly. It looks like the entire assembly, including needle bar, presser bar, tension control and thread take-up lever, may separate completely from the arm.
I haven't tried it yet. If this is true, its removal from the arm could affect the timing at the very least, if not reassembled in such a way as to preserve the exact position of all parts. A manual would help for this, too. Like the ball bearings in the clutch, mentioned earlier, I'd like to know what's in there and how it comes apart, and more importantly how it goes back together correctly.
Presser Foot Lever - This is a departure from more common and widespread designs. Very simple in operation, one rotating lever located on the outside of the machine, raises the foot and releases the thread tension at the same time.
This lever may operate more smoothly after it is cleaned and oiled. Since I'm more used to the other type of flip-up lever, above and behind the needle, I find it a little awkward.
(Tension Control) (Presser Foot Lever)
[ATTACH=CONFIG]518225[/ATTACH]
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Bobbin Hook Drive Mechanism - I've saved what I think is the most interesting difference for last. It is in two parts. And probably only of interest to geeks. (obviously I must be one)
First, I've noticed that turning shafts and bevel gears are commonly used in rotary hook machines. The designers of this machine managed to get a stall-proof rotary drive to the bottom of the machine with a single connecting rod. Quite a feat.
Second, is the rotation of the hook itself. Almost all rotary bobbin hooks turn twice for every needle stroke. This is necessary to have enough speed picking up the thread and getting it around the bobbin quickly enough to form the stitch. There is a clever mechanism on this machine that speeds the bobbin hook up, while getting the thread around the bobbin, then slows it down until the next needle drop. It changes speed like this during each rotation. By doing this, it accomplishes in one hook rotation what other rotary machines do in two.
(Machine Bottom)
[ATTACH=CONFIG]518227[/ATTACH]
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In closing, I would welcome thoughts from anyone who might know something about this machine or have any comments on it. Anything at all would be received with appreciation.
And lastly, thank you for reading this post, if you've made it this far.