If look this photo you see rasing block for 8" swing . I new it 7" but think they would try hard to hide it 
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Re: Erratic spindle speed
On Wed, Dec 6, 2023 at 12:37 AM, Thomas Key wrote:
What¡¯s a good contact cleaner?
I use one from CRC called "QD Contact Cleaner". Regarding replacement pot/switch combinations you need to pay attention to the switch -- whether the original is normally-open or normally-closed.? IIRC, the OEM version is opposite from the ones you normally find.
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Re: Erratic spindle speed
Yes there are several ?¡°numbers¡± but which numbers mater? ?If you have a generic 7x lathe then you can buy an exact replacement part from LMS. ? The 7X uses a pot that is slightly hard to find and LMS offers an easy solution.
But if this is from some different lathe, you have to remove the pot and inspect it. ? The brand or manufacturer does not matter, but all pots can be identified by measuring them with an ohm meter. ?You need to find or (by measuring) a few things:
1) What is the resistance, in Ohms between the two outside terminals or pins? ?Ignore the center pin for now. ? ?This will be something. Like 1000, 10,000 or 50,000 Ohms. ? it will be some kind of round number like that. ?So round the measurement you get so that it has a few zeros on the end.
2) Some pots have a switch built-in and these will have more than three terminals, likely 5. ?Does yours have the switch? ?These switched pots are for a combined on/off speed control. ?The stranded pots are speed-only controls.
3) the center tap will change as you rotate the knob. ?Measure the resistance relative to one of the other three pins. ? The resistnce will be either (a) proportional ?to the amount you turn the knob. ? In other words, a halfway know angle gives half the resistance or (b) very non-linear. ?The first is called a ¡°linear pot¡± the second is called ¡°audio taper¡± or ¡°log taper¡±,
As long as the replacement pot has all three characteristics matched, and can physically fit in the space you are good to go.
Different manufacturers will use different parts numbering codes to describe the pot. ?Although for example, 25,000 Ohms is always written ¡°25K"
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On Dec 6, 2023, at 8:04?AM, Thomas Key <takey89@...> wrote:
?? Should numbers on backside or on side.
There are different brands but the numbers tells which one to buy.??
Dave?
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Re: Gear ratio/ lead screw confusion
You find most programs for threading calculations will use 0.1% .
You can for most work you can go as high as 2% in a pinch 4%.?
Dave?
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Re: Erratic spindle speed
Should numbers on backside or on side.
There are different brands but the numbers tells which one to buy.??
Dave?
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Re: Erratic spindle speed
Dave¡what brand potentiometer should I buy if I need to replace the original?Tom?
The other problem if cleaner does fix .
The Chinese use low quality?
Potentiometer.
Dave?
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Re: Erratic spindle speed
What¡¯s a good contact cleaner?? Tom
Try spraying some contact cleaner into the speed control pot, then turning the pot from full-off to full-on & back several times to distribute the cleaning fluid.
Natch, do this with the lathe unplugged.? If this doesn't work you're looking at replacing the pot.
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Re: Erratic spindle speed
The other problem if cleaner does fix .
The Chinese use low quality?
Potentiometer.
Dave?
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Re: Erratic spindle speed
Try spraying some contact cleaner into the speed control pot, then turning the pot from full-off to full-on & back several times to distribute the cleaning fluid.
Natch, do this with the lathe unplugged.? If this doesn't work you're looking at replacing the pot.
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Re: belt slip on Mini Lathe Machine with 600W
I think it better or replace to use a 1725 rpm? motor.?
You get less belt slip.
Dave?
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My 15+yr old Speedway 10x14 lathe has recently developed erratic spindle speed. ?The lathe has had pretty heavy use and is now kicking into max RPM on its own at times¡.very unnerving and dangerous. ?There are also times when the chuck has jerky movement with the speed knob set at zero and the only way to stop it is with the kill switch.
Is the a simple fix like replacing the?potentiometer (+- $20) or will the entire power box (+- $200).
Thanks in advance for your help.
Tom
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Re: belt slip on Mini Lathe Machine with 600W
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I measured the motor speed as about 5000 RPM. I have it geared
down to give a spindle speed of 2200 RPM.
Tom
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Re: belt slip on Mini Lathe Machine with 600W
I have noticed that speed (5,000 RPM) on higher wattage/HP? motors.?
There one found that had 6,000 PRM.
Dave?
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Re: belt slip on Mini Lathe Machine with 600W
I measured the motor speed as about 5000 RPM. I have it geared down to give a spindle speed of 2200 RPM.
Tom
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Re: $1000 Budget: Which 7 x 14 to buy?
I got desperate for a wheel setup. So just cranked out a shaft. Kinda sloppy but it actually worked. Then for a wheel i found a baby stroller dumped in my back alley. And surprise , it had two nice front wheels that are about the same 9in or so. Just put some grub screws through the hub and this secured the wheel to the shaft. So far so good.
george ,?
On Sunday, December 3, 2023 at 11:43:34 AM PST, John Mattis <john.mattis@...> wrote:
I got a new Speedway mini lathe about 21 years ago. It's not perfect, but I have made several modifications to make it better. Perhaps the?best one is the modification I made to he change gear adjuster which is described in the attachment. I have also?attached a pdf of my?handwheel design. I have drawings and photos of everything?I have done and they are available on request. Regards,? John Mattis (retired mechanical engineer)
Forget about getting a perfect Chinese lathe. If it were tinkered into perfection at the factory, it would be like the British Myford lathe ($5000+).?
Instead, you can buy a Chinese mini-lathe and tinker it into perfection yourself.? Improving your new lathe is a good way to learn basic metalworking skills and (unlike with vintage American lathes), if you screw something up the parts are easily replaced.
Mike Taglieri?
On Sun, Dec 3, 2023, 1:55 PM mike allen < animal@...> wrote:
Unfortunately that seems to be the new norm with a lot of
purchased items these days . Reading some of the reviews for
things on Amazon& other sites? just enforces that statement .
animal
On 12/3/23 6:57 AM, Craig Hopewell via
wrote:
And some get total crap from Grizzly and LMS.
My old SIEG Homier 7x12 was far better finished (ways and
cosmetics) than two Grizzly 7x14's and one LMS 7x16 lathes.? ?One
Grizzly seized and the other would not reliably shut off - both
went back, and finally got a refund.? ?The LMS (that I received)
may be the worst finished of all four.
I stand by my statement.? ?Buy the cheapest (that has a free
return), with consideration of the variants, and hope for one that
is serviceable with minimal tuning.
--
Lone Tree, Colorado? ?USA
Attachments:
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Re: $1000 Budget: Which 7 x 14 to buy?
Hi Mike.?
I went with the Clough 42 controller system.? ? It interfaces with a Texas Instruments board and the software that is needed is available on GitHub.? ? There's also a forum on GitHub for support, etc.? James (Clough42) has a full video series on YouTube about how he designed and built the controller and software.? The system, the Clough42 kit has a board that plugs into the Texas Instruments board, a rotary encoder is used to feed RPM data back to the TI board and then the TI board drives a stepper motor to drive the lead screw through a belt and pulleys.? It sounds a bit complex but it's really not.? I'm not great with electronics stuff and this was fairly easy.? My stepper motor and encoder came from Amazon,? the TI board I ordered direct from them and the belts and pulleys and Clough42 kit I got through eBay.? I built my own mount for the stepper motor and it mounts to the lathe where one of the change gear parts was originally.? The whole mount pivots to adjust belt tension.? With all the parts, pieces and aluminum to build my motor mount I spent just over $400.00 US and to me it's been worth every penny as I often do tiny little projects that I single point thread and this allows me to turn to a finish diameter, do any SAE or metric thread with the push of some buttons and go right back to using the lead screw feed to turn.? It's literally seconds from turning to threading back to turning.?
encoder I used
stepper
power supply
and a picture
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Re: $1000 Budget: Which 7 x 14 to buy?
I got a new Speedway mini lathe about 21 years ago. It's not perfect, but I have made several modifications to make it better. Perhaps the?best one is the modification I made to he change gear adjuster which is described in the attachment. I have also?attached a pdf of my?handwheel design. I have drawings and photos of everything?I have done and they are available on request. Regards,? John Mattis (retired mechanical engineer)
Forget about getting a perfect Chinese lathe. If it were tinkered into perfection at the factory, it would be like the British Myford lathe ($5000+).?
Instead, you can buy a Chinese mini-lathe and tinker it into perfection yourself.? Improving your new lathe is a good way to learn basic metalworking skills and (unlike with vintage American lathes), if you screw something up the parts are easily replaced.
Mike Taglieri?
On Sun, Dec 3, 2023, 1:55 PM mike allen < animal@...> wrote:
Unfortunately that seems to be the new norm with a lot of
purchased items these days . Reading some of the reviews for
things on Amazon& other sites? just enforces that statement .
animal
On 12/3/23 6:57 AM, Craig Hopewell via
wrote:
And some get total crap from Grizzly and LMS.
My old SIEG Homier 7x12 was far better finished (ways and
cosmetics) than two Grizzly 7x14's and one LMS 7x16 lathes.? ?One
Grizzly seized and the other would not reliably shut off - both
went back, and finally got a refund.? ?The LMS (that I received)
may be the worst finished of all four.
I stand by my statement.? ?Buy the cheapest (that has a free
return), with consideration of the variants, and hope for one that
is serviceable with minimal tuning.
--
Lone Tree, Colorado? ?USA
|
Re: $1000 Budget: Which 7 x 14 to buy?
Forget about getting a perfect Chinese lathe. If it were tinkered into perfection at the factory, it would be like the British Myford lathe ($5000+).?
Instead, you can buy a Chinese mini-lathe and tinker it into perfection yourself.? Improving your new lathe is a good way to learn basic metalworking skills and (unlike with vintage American lathes), if you screw something up the parts are easily replaced.
Mike Taglieri?
On Sun, Dec 3, 2023, 1:55 PM mike allen < animal@...> wrote:
Unfortunately that seems to be the new norm with a lot of
purchased items these days . Reading some of the reviews for
things on Amazon& other sites? just enforces that statement .
animal
On 12/3/23 6:57 AM, Craig Hopewell via
wrote:
And some get total crap from Grizzly and LMS.
My old SIEG Homier 7x12 was far better finished (ways and
cosmetics) than two Grizzly 7x14's and one LMS 7x16 lathes.? ?One
Grizzly seized and the other would not reliably shut off - both
went back, and finally got a refund.? ?The LMS (that I received)
may be the worst finished of all four.
I stand by my statement.? ?Buy the cheapest (that has a free
return), with consideration of the variants, and hope for one that
is serviceable with minimal tuning.
--
Lone Tree, Colorado? ?USA
|
Re: $1000 Budget: Which 7 x 14 to buy?
Unfortunately that seems to be the new norm with a lot of
purchased items these days . Reading some of the reviews for
things on Amazon& other sites? just enforces that statement .
animal
On 12/3/23 6:57 AM, Craig Hopewell via
groups.io wrote:
toggle quoted message
Show quoted text
And some get total crap from Grizzly and LMS.
My old SIEG Homier 7x12 was far better finished (ways and
cosmetics) than two Grizzly 7x14's and one LMS 7x16 lathes.? ?One
Grizzly seized and the other would not reliably shut off - both
went back, and finally got a refund.? ?The LMS (that I received)
may be the worst finished of all four.
I stand by my statement.? ?Buy the cheapest (that has a free
return), with consideration of the variants, and hope for one that
is serviceable with minimal tuning.
--
Lone Tree, Colorado? ?USA
|
davesmith1800
John Mattis