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Date
Re: Erratic spindle speed

 

Hi Tom,
The fwd/rev switch is prone to having swarf fall through the opening around the lever and cause major damage to the electronics should it short the wrong terminals.? Consider fitting a shield to this switch to avoid this, for an example see the top picture here:?

Also consider checking for and removing swarf that has previously made its way into this switch.

John
Re: dividing wheel

 

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please, when you send a message, put the original language as well. At least, GoogleTrans will help.

Thks


On 07.12.23 23:03, Jacques Savard via groups.io wrote:

somebody cab? schow me? ?howto? make? the? wheell whit?? all the? hole?cab

I do not? hVE? nY? MILLING? JUST? A VINTAGE? LATE
AND A DRILL
how? you can make? all these? hole??

maybe? you have? way? to? do it? simple

jack 47 71

Re: Adjusting Gears Just Right

 

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It's pretty common on these lathes to have the? lead screw bracket's mounting wonky .A lot of folks have had to re drill/enlarge the screw holes to get things lined up .

animal

On 12/7/23 4:03 PM, CBJessee-N4SRN wrote:

I should have noted - I have just upgraded my LMS 7x12 with a 7x16 Bed Extension and find the gnashing is actually Gear B just barely contacting behind Gear D on it's back edge. The gears have ~2/3 engagement, likely due to problems noted below.

My Left Lead Screw Bracket is a bit beyond flush with the left edge of the bed casting and my Change Gear Adjusting Stud might not be quite located properly. LMS instructions are "On your original bed way casting, measure the distance from the front edge to the center of the hole for the change gear adjusting stud. If it is over 21/32" or less than 19/32", use the dimension you measured instead of 5/8" in the step above." My stud was 0.5" set back on my 2013 model LMS 4200 7x12, so I went with 0.5" as indicated.

I'll get a picture when home again and post - sorry if I'm not describing it well. I'm hoping some tweaks might help fix the issues. At worst, I can grind back the read edge of the 80-tooth Gear B. :-(

Trying to precision drill holes in the bed casting proved quite difficult, even with a drill guide.

BRET

Re: Adjusting Gears Just Right

 

Like the pdf how complex it can be .
The way I found is paper between the gears on setup. It fast and easy.?
Most gears like a gap of 0.005" [0.12mm] .
You adjust the paper layers till gears run quite.?
Today I can feel the gap need.

The 0.005" [0.12mm]?gap is only for most change gears in machine shop. Larger gears needs a greater gap and watch gears need a lot less. But here we do not care we are working with mini lathes.?

Dave?
Re: Adjusting Gears Just Right

 
Edited

? Here's that gear problem picture. Adding an M8 washer on the Stud moved Gear B off contacting the Left Bracket and gears engage more - is that a reasonable solution?
Re: Milling attachment for mini lathe

 

I like photos posted?
It helps see how others did the setup.?

This not my first mill attachment.?
I had a Pamgram on 9A South Bend back in the 1960's.??
Then did not know what I was doing.??
I learn with Lathe , Drill press and welding equipment.? I did line boring with just ?" hand drill.?
?I did not have any one say can done.?

Dave?
Re: Adjusting Gears Just Right

 

I read somewhere (don't remember) that if you use a slip of thin paper (newsprint works well) between the gears, that is the clearance you need. You crush the paper as you mesh the gears and tighten. Then you had turn the gear train by hand to get the paper out and then put some grease on the gears. That is how I put the banjo to mesh on my lathe...

On Thu, Dec 7, 2023 at 1:46?PM CBJessee-N4SRN <cbjesseeNH@...> wrote:
The LMS 7x16 manual says “?Proceed to move the shaft carrying B and C and the adjuster 'A' so that all gears mesh correctly, then tighten the adjuster securing nuts. This may take one or two attempts but make sure there is as little backlash as possible without being over-tight, (Turn the spindle by hand to test for backlash).”

If I just press the adjuster firmly up by hand and tighten the nut, the lathe seems to make a gnashing sound - is that what “over-tight” sounds like?

BRET


--
Buffalo John
Re: Adjusting Gears Just Right

 

I should have noted - I have just upgraded my LMS 7x12 with a 7x16 Bed Extension and find the gnashing is actually Gear B just barely contacting behind Gear D on it's back edge. The gears have ~2/3 engagement, likely due to problems noted below.

My Left Lead Screw Bracket is a bit beyond flush with the left edge of the bed casting and my Change Gear Adjusting Stud might not be quite located properly. LMS instructions are "On your original bed way casting, measure the distance from the front edge to the center of the hole for the change gear adjusting stud. If it is over 21/32" or less than 19/32", use the dimension you measured instead of 5/8" in the step above." My stud was 0.5" set back on my 2013 model LMS 4200 7x12, so I went with 0.5" as indicated.

I'll get a picture when home again and post - sorry if I'm not describing it well. I'm hoping some tweaks might help fix the issues. At worst, I can grind back the read edge of the 80-tooth Gear B. :-(

Trying to precision drill holes in the bed casting proved quite difficult, even with a drill guide.

BRET
Re: dividing wheel

 

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If you have the circular piece of metal you want to make into the wheel you can do the following:

Clickspring has a good video on how-to mark out these holes?

If you have access to Dave Gingery’s books (I have the compendium version, so I don’t remember which book it’s in) he shows a method to make them with just a drill press.



On Dec 7, 2023, at 3:03 PM, Jacques Savard <jacquessavard@...> wrote:

somebody cab? schow me? ?howto? make? the? wheell whit?? all the? hole?cab

I do not? hVE? nY? MILLING? JUST? A VINTAGE? LATE
AND A DRILL
how? you can make? all these? hole??

maybe? you have? way? to? do it? simple

jack 47 71

--?
Bruce Johnson

The less a man knows about how sausages and laws are made, the easier it is to steal his vote and give him botulism.

Re: Erratic spindle speed

 

Tom,
Is the F/O/R switch a DPDT (for just switching the polarity to the DC motor) or are there additional poles on that switch? Some of the mini lathes have an additional? pole on the F/O/R switch that connects the controller board's P1 to P4 connections for reverse. Some have P1 and P4 hard wired, so there would be 2 wires going to P1, one to P4 and the other being a wire to the pot. If you removed the pot for cleaning and disconnected the wires to P1,P2,P3, there is a chance that a connection became open during the whole process.

Pictures of the wiring would be helpful.

Regards,
Gary
Re: Adjusting Gears Just Right

 

Yeah, probably too tight. The plastic gears also tend to have tight and loose spots. When I was using them I set like I did back when I raced RC and slot cars. Use some news print. Put two thicknesses between the gears and hold them firmly together but not super griped. Tighten the adjuster down and remove the paper. You should be able to feel a little movement between the gears when it is set.?

Ryan?
On Dec 7, 2023 at 5:04?PM -0500, John Mattis <john.mattis@...>, wrote:

Bret,
I got frustrated?with adjusting the change gears a while back. and conceived?the design shown in the attached PDF.
I have posted this before.
Regards,
John Mattis (retired mechanical?engineer)



On Thu, Dec 7, 2023 at 1:46?PM CBJessee-N4SRN <cbjesseeNH@...> wrote:
The LMS 7x16 manual says “?Proceed to move the shaft carrying B and C and the adjuster 'A' so that all gears mesh correctly, then tighten the adjuster securing nuts. This may take one or two attempts but make sure there is as little backlash as possible without being over-tight, (Turn the spindle by hand to test for backlash).”

If I just press the adjuster firmly up by hand and tighten the nut, the lathe seems to make a gnashing sound - is that what “over-tight” sounds like?

BRET

Attachments:
Re: Milling attachment for mini lathe

 

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On Dec 7, 2023, at 3:42 PM, Bruce J via groups.io <bruce.desertrat@...> wrote:

I have the same ( or similar clone) ?one, I made a small pallet with a piece of ?” plate to attach to my cross slide in place of the compound. The screws shown fit into the mount for the compound, and there are two more ?on the far side if the vise that go into threaded holes that I made in the cross-slide. ?The attachment itself is mounted with two tapped holes in the pallet matching the ones in the base. I intend to make a rear-mounted cut-off tool that will mount on a similar pallet with the same mounting pattern.?

Forgot to mention that this design makes it very simple to accurately clamp workpieces in the attachment; remove the four screws holding it to the cross-slide and clamp the whole thing ‘on it’s back’ I’m my bench vise where I can get to all sides with a square while tightening the jaws.

--?
Bruce Johnson

The less a man knows about how sausages and laws are made, the easier it is to steal his vote and give him botulism.

Re: Milling attachment for mini lathe

 

开云体育

I have the same ( or similar clone) ?one, I made a small pallet with a piece of ?” plate to attach to my cross slide in place of the compound. The screws shown fit into the mount for the compound, and there are two more ?on the far side if the vise that go into threaded holes that I made in the cross-slide. ?The attachment itself is mounted with two tapped holes in the pallet matching the ones in the base. I intend to make a rear-mounted cut-off tool that will mount on a similar pallet with the same mounting pattern.?

FDDDAF70-4431-448E-BB67-72872475082F_1_105_c.jpeg

It worked pretty well this shows a test piece (the one in the back) and an actual part (a new tailstock center for my wood lathe, the keyway is ?” done in three passes, iirc ) I clamped it in my magnetic vise round-stock jaws I made a long time ago for my bench vise. I overshot the first pass by a bit.

80AD3FC0-95A9-43A7-9EE3-F8893AF3E2D9_1_105_c.jpeg

The new next to the old?

F964A1C9-643F-41AB-8F74-AD8B3B8B8F0F_1_105_c.jpeg

Ted Hansen’s Complete Mini-Lathe Workshop from Village Press has a bunch of good info about milling operations on the mini lathe (among an enormous amount of other info)




On Dec 7, 2023, at 1:47 PM, davesmith1800 <davesmith1@...> wrote:

It made in China.?
They do there designing by just copying a good product.?
It cost $59.00 free shipping.?
It part of my down sizing It nice to have some type mill.?

The next part is mounting to lathe.?
The first is to mount the tool post. The compound that came lathe was to high so got one that fits but is off a 7" lathe just right hight.

Dave?

--?
Bruce Johnson

The less a man knows about how sausages and laws are made, the easier it is to steal his vote and give him botulism.

Re: Adjusting Gears Just Right

 

Bret,
I got frustrated?with adjusting the change gears a while back. and conceived?the design shown in the attached PDF.
I have posted this before.
Regards,
John Mattis (retired mechanical?engineer)



On Thu, Dec 7, 2023 at 1:46?PM CBJessee-N4SRN <cbjesseeNH@...> wrote:
The LMS 7x16 manual says “?Proceed to move the shaft carrying B and C and the adjuster 'A' so that all gears mesh correctly, then tighten the adjuster securing nuts. This may take one or two attempts but make sure there is as little backlash as possible without being over-tight, (Turn the spindle by hand to test for backlash).”

If I just press the adjuster firmly up by hand and tighten the nut, the lathe seems to make a gnashing sound - is that what “over-tight” sounds like?

BRET

Change Gear Adjuster.pdf
Change Gear Adjuster.pdf

dividing wheel

 

somebody cab? schow me? ?howto? make? the? wheell whit?? all the? hole?cab

I do not? hVE? nY? MILLING? JUST? A VINTAGE? LATE
AND A DRILL
how? you can make? all these? hole??

maybe? you have? way? to? do it? simple

jack 47 71

Re: Erratic spindle speed

 

开云体育

Easy to check continuity on the switch with a VOM…or maybe a wire got disconnected while you were fixing the fuse.

On Dec 7, 2023, at 1:06 PM, Thomas Key <takey89@...> wrote:

Thanks everyone for you response.? I cleaned the pot with alcohol and while I was inside found that the fuse holder had a loose wire.? Put everything back together and the erratic RPM problem is solved (pot or fuse?, but now the chuck won’t turn clockwise. ?? Guess that means the forward/off/reverse switch is faulty.

Tom

<image_6483441.JPG>

On Wed, Dec 6, 2023 at 11:52 AM Chris Albertson <albertson.chris@...> wrote:
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"



On Dec 6, 2023, at 8:04?AM, Thomas Key <takey89@...> wrote:

??

On Wed, Dec 6, 2023 at 7:29 AM davesmith1800 <davesmith1@...> wrote:
Should numbers on backside or on side.
There are different brands but the numbers tells which one to buy.??

Dave?






--?
Bruce Johnson

The less a man knows about how sausages and laws are made, the easier it is to steal his vote and give him botulism.

Re: Milling attachment for mini lathe

 

It made in China.?
They do there designing by just copying a good product.?
It cost $59.00 free shipping.?
It part of my down sizing It nice to have some type mill.?

The next part is mounting to lathe.?
The first is to mount the tool post. The compound that came lathe was to high so got one that fits but is off a 7" lathe just right hight.

Dave?

Re: Erratic spindle speed

 

Thanks everyone for you response.? I cleaned the pot with alcohol and while I was inside found that the fuse holder had a loose wire.? Put everything back together and the erratic RPM problem is solved (pot or fuse?, but now the chuck won’t turn clockwise. ?? Guess that means the forward/off/reverse switch is faulty.

Tom


On Wed, Dec 6, 2023 at 11:52 AM Chris Albertson <albertson.chris@...> wrote:
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"



On Dec 6, 2023, at 8:04?AM, Thomas Key <takey89@...> wrote:

??

On Wed, Dec 6, 2023 at 7:29 AM davesmith1800 <davesmith1@...> wrote:
Should numbers on backside or on side.
There are different brands but the numbers tells which one to buy.??

Dave?



Re: Milling attachment for mini lathe

 

开云体育

Except for the second handle that looks identical to the one for the Taig lathe .

animal

On 12/7/23 8:52 AM, davesmith1800 wrote:

Just got my milling attachment for my new lathe.?

Dave?

Attachments:

Milling attachment for mini lathe

 

Just got my milling attachment for my new lathe.?

Dave?

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