Sergei Slovenija
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I can not guess what it means in the settings.
60 at the bottom, 30 at the top.
60 at the bottom, 30 at the top.
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Sergei Slovenija
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Photo gears and number of teeth. The design allows you to put other gears (the axis slides into the slot of the lever + nut). There are no other spare gears for the machine.
Agroshield
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Can you post a photo of the full plate please.
It is the screwcutting plate. Everything on the plate can be done with the standard 30-60 gearing (and equal idler gears). Anything not on the plate will need other gears.
There are four thread series shown on it: metric, Whitworth, module and diam(etral pitch) (abbreviated DP). The first is obvious. The second is called Whitworth but might better be called 'imperial' as then there is no doubt it covers both Whitworth and UN (American) threads. Module and diametral pitch threads are used when cutting a worm thread, to mesh with a standard gear. Module is metric and DP imperial. A 1 MOD thread has a pitch of pi (3.142)mm*. 1 MOD is equal to 25.4 DP.
When cutting a worm thread, somewhere in the gearing you need gears that approximate a multipe of pi. It looks like 'B' engages those gears as it is common to both module and DP. 'E-F' work as doublers or halfs as it is common to module and metric above.
* and one of the coincidences of the imperial/metric conversion is that 1 MOD is very, very close to 8tpi (3.175mm pitch).
It is the screwcutting plate. Everything on the plate can be done with the standard 30-60 gearing (and equal idler gears). Anything not on the plate will need other gears.
There are four thread series shown on it: metric, Whitworth, module and diam(etral pitch) (abbreviated DP). The first is obvious. The second is called Whitworth but might better be called 'imperial' as then there is no doubt it covers both Whitworth and UN (American) threads. Module and diametral pitch threads are used when cutting a worm thread, to mesh with a standard gear. Module is metric and DP imperial. A 1 MOD thread has a pitch of pi (3.142)mm*. 1 MOD is equal to 25.4 DP.
When cutting a worm thread, somewhere in the gearing you need gears that approximate a multipe of pi. It looks like 'B' engages those gears as it is common to both module and DP. 'E-F' work as doublers or halfs as it is common to module and metric above.
* and one of the coincidences of the imperial/metric conversion is that 1 MOD is very, very close to 8tpi (3.175mm pitch).
Sergei Slovenija
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Based on the explanations, it turns out that I have one gear 30 and 3 gears 60. Corresponds to the diagram.
Sergei Slovenija
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Agroshield
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Thanks. It is quite comprehensive.
What is it missing? In metric, 0.6 (M3.5), 0.7 (M4) and 0.8 (M5). In imperial 11.5 (only used for US NPT pipe threads), 13 (1/2" UNC) and 26 (1/4 BSF).
If you had a need for these threads, you would have to put different gears in place of the 60-60 idlers you have. If you remove those gears, are their carriers mounted in a way that will allow the centres to be varied? At the bottom of the cluster, it looks like the two can be rotated.
If the centres can be varied and the whole lot rotated, you have round about 120 teeth total (i.e. you might get from 115 to 125 in the space) that you can proportion in the ratio you need to achieve the missing ones. Right now, they run at 1:1 ratio, so to get 0.6mm pitch, you can use 75 and 45 (120 total) with the gearbox set to 1mm pitch. For 0.7mm pitch maybe 49 and 70 (119 teeth total). For 0.8mm pitch, 52/65 (117 total) or 56/70 (126 total) might work if space and adjustment allowed. The 70 has already been seen so it now potentially has two uses. The 65 contains 13 as a factor, so might be useful later on for the missing imperial pitches.
What is it missing? In metric, 0.6 (M3.5), 0.7 (M4) and 0.8 (M5). In imperial 11.5 (only used for US NPT pipe threads), 13 (1/2" UNC) and 26 (1/4 BSF).
If you had a need for these threads, you would have to put different gears in place of the 60-60 idlers you have. If you remove those gears, are their carriers mounted in a way that will allow the centres to be varied? At the bottom of the cluster, it looks like the two can be rotated.
If the centres can be varied and the whole lot rotated, you have round about 120 teeth total (i.e. you might get from 115 to 125 in the space) that you can proportion in the ratio you need to achieve the missing ones. Right now, they run at 1:1 ratio, so to get 0.6mm pitch, you can use 75 and 45 (120 total) with the gearbox set to 1mm pitch. For 0.7mm pitch maybe 49 and 70 (119 teeth total). For 0.8mm pitch, 52/65 (117 total) or 56/70 (126 total) might work if space and adjustment allowed. The 70 has already been seen so it now potentially has two uses. The 65 contains 13 as a factor, so might be useful later on for the missing imperial pitches.
Seadog
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The two intermediate wheels can be any number of teeth. The primary (30T) and the final (bottom 60T) determine the ratio (2:1). The two intermediate changewheels ensure that the spindle rotation and the lead screw rotation are in the same direction.
Sergei Slovenija
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Ursus gears video.
Why is there a thread on the spindle shaft? There is no access to it with a protective cover on.
Why is there a thread on the spindle shaft? There is no access to it with a protective cover on.
Sergei Slovenija
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The gap between the cover and the spindle shaft seems to be small.
Pete.
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Perhaps there is a different cover for the collet closer. My lathe does.
Sergei Slovenija
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First iron blood 
I've been waiting for this moment for a long time.
I've been waiting for this moment for a long time.
Sergei Slovenija
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One of the motor windings burned out. Tomorrow I'll take it to a specialized workshop for rewinding. Issue price 230 euros + VAT. It looks like the motor is very old school. The winding wires are soldered to brass threaded lugs. Under the contact pad - cardboard insulation.
Old Italian designation for motor power in horsepower (Cv 5 - cavalry)
Old Italian designation for motor power in horsepower (Cv 5 - cavalry)
Pete.
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Are you sure? What checks have you made?
Sergei Slovenija
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My electrician checked. A megameter and some more complex device, the size of an oscilloscope.
+ The starting current, measured with clamps, showed on two devices more than 15 amperes.
I understand little of this. The engine died slowly. It just stopped abruptly (almost instantly), without the inertia of a lathe chuck + high-frequency hum, like a transformer. When reconnected, continued to work. But this did not last long. Managed to get the job done. Repair will take 3-4 days.
Off - When I was looking for a service, I found at least 4 companies that rewind the collector motors of hand tools, with the replacement of the collector. I have been looking at the old Biax scraper for a long time, the blue series, for which they do not sell spare parts. Now it makes sense to buy it cheap.
Pete.
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Off - When I was looking for a service, I found at least 4 companies that rewind the collector motors of hand tools, with the replacement of the collector. I have been looking at the old Biax scraper for a long time, the blue series, for which they do not sell spare parts. Now it makes sense to buy it cheap.
Those are easy to re-wind. 307 turns of 0.224mm (31awg) wire.
Or you could go full variable-speed portable...
