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I need to machine some wider material.
Googling I can find lots of approaches and I'm struggling with what is considered the best approach in 2022 (ideas tend to evolve).
Gordon Scotts:?
Gadget Builfers:???(extends on above but incorporates a handle extension)
Twinsquirrel:??(handle extension is frowned upon and there is mention of buying and cutting down a longer screw from LMS).
Mikesworkshop:??(referenced in the above madmodder,? made his own longer screw but at end mentions not lengthening slot in carriage [hindsight]).
Maybe if I take everything apart and pour over the above 4 threads in more detail the subtleties of the differences would become apparent,? but instead I thought I'd ask :-)
Thanks!
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I did Gordon Scott's method years ago & have been pleased with it.
Roy
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My understanding is that the Gordon Scott mod moves the effective range of the leadscrew towards the operator (so you can cut wider material since you've moved the cut position relative to spindle).? However you're not gaining any additional travel.
has a so the effective range is increased plus moved towards the operator.
The Gadget Builder version appears to remedy try to increase the travel by adding an extension to the front of the shaft (which I presume is shown exposed out of the spacer in this image):??
This idea of a shaft extension is poo-poo'd on the?madmodder.page,? they seem to recommend a longer screw instead such as the above LMS.
I'm not understanding the "If I were doing this modification again then I would not mill out the carriage slot. Instead I would simply move the leadscrew nut? 25 mm further back on the cross slide. This would achieve the same result as extending the slot" comment on the?mikesworkshop page.
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I just finished up? an extended travel mod on my 7x a couple days ago. ?? I don't have access to a mill to cut the carriage and the LMS kit only addressed part of what I wanted to do so I did it all myself, on my lathe.? Mine ended up being pretty much what Mike did as I thought I had a new idea when I thought about moving the feed nut farther back on the carriage but it turns out Mike already had that idea, LOL!? I made my own spacer, 1.350" long from aluminum and drilled new mounting holes in the carriage that distance farther away from the operator.? That allows for the extended travel towards the operator.? I then made a new feed nut from 3/4" brass, mainly just because I wanted the nut and screw to be a "mated" pair.? The factory nut would work just fine.? For the feed screw I made one from a 12" piece of 12L14 steel.? By making my own new nut and screw I could thread the screw so it just fits the nut eliminating a lot of the backlash in the system without having to use the goofy factory adjusting system.? I ended up with a bit more than I wanted at around .008" but it's much improved. ? I originally thought about extending the original screw but in my opinion it was easier to turn a brand new one than try and extend the old one.? My screw is now about 10.5" long.???? :-D
What Mike means by "If I were doing this modification again then I would not mill out the carriage slot. Instead I would simply move the leadscrew nut? 25 mm further back on the cross slide. This would achieve the same result as extending the slot"? is that if you move the nut further back on the slide there's no need to mill out the slide.? Moving the nut back accomplishes the same goal, giving the nut more room to travel towards the operator.? Both? ways effectively do the exact same thing and no milling is needed with just moving the nut farther back.
Honestly, I have very... not even what I would call moderate skills, especially compared to many of the members here and this was a project that I was very capable of doing.? I bought 12" of brass and have 11" left and I bought 6 pieces of 12" 12L14 and have 5 of those left too.? I'm super happy with how it turned out.? Oh, the other thing I did buy for this project was live (rotating) center but it could be done with a dead center... but I wanted an excuse to buy live one, LOL.
My suggestion is to go the Mike route, moving the nut and make a new screw.? It was a fun project and my lathe has more capability than it did before.? Win Win situation!
Ryan
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Ryan H wrote:
>? I don't have access to a mill to cut the carriage and the LMS kit only addressed part of what I wanted to do so I did it all myself, on my lathe.?
I have a mill, several.? ??
Curious what was lacking in the LMS kit?? it seems to achieve both more travel and relocating the travel.? The same as "the Mike route".? Obviously it's $$$ and not DIY
> What Mike means by "If I were doing this modification again then I would not mill out the carriage slot. Instead I would simply move the leadscrew nut? 25 mm further back on the cross slide.
> This would achieve the same result as extending the slot"? is that if you move the nut further back on the slide there's no need to mill out the slide.? Moving the nut back accomplishes the same
> goal, giving the nut more room to travel towards the operator.? Both? ways effectively do the exact same thing and no milling is needed with just moving the nut farther back.
I understood the wording of what he wrote wrt accomplishing the same (and what you say isn't - no offense intended - any clearer) but I'm just not grokking it :-)? I suspect it won't make any sense until I take everything apart and re-read at which time I'll have an "ah ha!" moment.
I do like the idea of making a new screw from the perspective of also making a custom mated feed nut.? ? ? I'm assuming it would alleviate the need to do this:?
Thanks for the reply.
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For my needs, the LMS kit lacked extended travel away from the operator. I need to be able to move the tool holder past the chuck for a part I make. I have a fixture in a quick change tool holder that holds three small parts that get a 1.3mm slot milled it them. I put the end mill in the chuck and feed the parts past it to cut a screwdriver slot. Not optimal but when lacking a mill it works fairly well. And beats the way I was doing it, cutting a slot with a Dremel tool and filing each one by hand.?
Ryan
On Feb 21, 2022, 1:31 AM -0500, Tony Jones <tony@...>, wrote:
Ryan H wrote:
> I don't have access to a mill to cut the carriage and the LMS kit only addressed part of what I wanted to do so I did it all myself, on my lathe.
I have a mill, several.
Curious what was lacking in the LMS kit? it seems to achieve both more travel and relocating the travel. The same as "the Mike route". Obviously it's $$$ and not DIY
> What Mike means by "If I were doing this modification again then I would not mill out the carriage slot. Instead I would simply move the leadscrew nut 25 mm further back on the cross slide.
> This would achieve the same result as extending the slot" is that if you move the nut further back on the slide there's no need to mill out the slide. Moving the nut back accomplishes the same
> goal, giving the nut more room to travel towards the operator. Both ways effectively do the exact same thing and no milling is needed with just moving the nut farther back.
I understood the wording of what he wrote wrt accomplishing the same (and what you say isn't - no offense intended - any clearer) but I'm just not grokking it :-)? I suspect it won't make any sense until I take everything apart and re-read at which time I'll have an "ah ha!" moment.
I do like the idea of making a new screw from the perspective of also making a custom mated feed nut.? ? ? I'm assuming it would alleviate the need to do this:?
Thanks for the reply.
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I'm sure you'll see why moving the nut back or extending the slot forward accomplishes the same thing as soon as you can physically see what is happening. Either one gives more room for the nut to travel towards the operator before it hits something. Hard to explain but much more obvious visually. You'll definitely have that Ah-ha! moment! :-)
I looked at the split nut mod but it didn't seem to keep adjustment all that well for Mike so I didn't do it. I'm hoping mine stays about the .008 I have now. I'll be happy with that :-). Perfect???No but a vast improvement over what I had before and I think if the thread was cut with the help of a traveling steady it would help the precision of the thread but again I don't have one of those.?
Ryan
On Feb 21, 2022, 1:44 AM -0500, Ryan H via groups.io <ifly172@...>, wrote:
For my needs, the LMS kit lacked extended travel away from the operator. I need to be able to move the tool holder past the chuck for a part I make. I have a fixture in a quick change tool holder that holds three small parts that get a 1.3mm slot milled it them. I put the end mill in the chuck and feed the parts past it to cut a screwdriver slot. Not optimal but when lacking a mill it works fairly well. And beats the way I was doing it, cutting a slot with a Dremel tool and filing each one by hand.?
Ryan
On Feb 21, 2022, 1:31 AM -0500, Tony Jones <tony@...>, wrote:
Ryan H wrote:
> I don't have access to a mill to cut the carriage and the LMS kit only addressed part of what I wanted to do so I did it all myself, on my lathe.
I have a mill, several.
Curious what was lacking in the LMS kit? it seems to achieve both more travel and relocating the travel. The same as "the Mike route". Obviously it's $$$ and not DIY
> What Mike means by "If I were doing this modification again then I would not mill out the carriage slot. Instead I would simply move the leadscrew nut 25 mm further back on the cross slide.
> This would achieve the same result as extending the slot" is that if you move the nut further back on the slide there's no need to mill out the slide. Moving the nut back accomplishes the same
> goal, giving the nut more room to travel towards the operator. Both ways effectively do the exact same thing and no milling is needed with just moving the nut farther back.
I understood the wording of what he wrote wrt accomplishing the same (and what you say isn't - no offense intended - any clearer) but I'm just not grokking it :-)? I suspect it won't make any sense until I take everything apart and re-read at which time I'll have an "ah ha!" moment.
I do like the idea of making a new screw from the perspective of also making a custom mated feed nut.? ? ? I'm assuming it would alleviate the need to do this:?
Thanks for the reply.
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> For my needs, the LMS kit lacked extended travel away from the operator.
The LMS kit has alonger screw (which should preserve the same position as stock away from the operstor) while the longer slot brings the position closer.? I thought this was as good as it got?
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?Ryan wrote:
I looked at the split nut mod but it didn't seem to keep adjustment all that well for Mike so I didn't do it. I'm hoping mine stays about the .008 I have now. I'll be happy with that :-). Perfect???No but a vast improvement over what I had before and I think if the thread was cut with the help of a traveling steady it would help the precision of the thread but again I don't have one of those.?
For information:? I have since installed a Delrin nut on my minilathe which works very well and this eliminates backlash very effectively. Details of this mod are on my website, see:
Mike
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That's pretty slick Mike!??I thought about doing an insert for the nut because like you say, I don't think threading straight into the plastic would hold. My thought was to do an insert piece that would have a nice course outside thread, screwed into a block of steel or brass. The metal block would of course be the main holding but with the holes drilled all the way through the screws would serve to keep the insert from unscrewing from the block or a few other screws could be used expressly to keep the insert in place. I'd have to measure sometime but I think a 3/4" or so block would fit under the slide. I think that would be sufficient size to hold an insert?
Thoughts?
On Feb 21, 2022, 6:03 AM -0500, drmico60 via groups.io <mikey.cox@...>, wrote:
Ryan wrote:
I looked at the split nut mod but it didn't seem to keep adjustment all that well for Mike so I didn't do it. I'm hoping mine stays about the .008 I have now. I'll be happy with that :-). Perfect? No but a vast improvement over what I had before and I think if the thread was cut with the help of a traveling steady it would help the precision of the thread but again I don't have one of those.
For information:? I have since installed a Delrin nut on my minilathe which works very well and this eliminates backlash very effectively. Details of this mod are on my website, see:
Mike
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A couple of years back I bought some
longer cross slide screws off of eBay. I am not sure if they were
custom made or actual parts from other lathes.? I made a couple of
educated guesses on the Grizzly web site and bought 3-4 screws for
other models of similar overall appearance, but none were a match
in any respect --- Fatter shaft, different pitch, different thread
form, etc.
Does anyone have any ideas if these
screws are custom made or repurposed OEM parts from a different
model(s)?
John
On 2/20/2022 7:19 PM, Tony Jones wrote:
toggle quoted message
Show quoted text
I need to machine some wider material.
Googling I can find lots of approaches and I'm struggling with
what is considered the best approach in 2022 (ideas tend to
evolve).
Gordon Scotts:?
Gadget Builfers:???(extends
on above but incorporates a handle extension)
Twinsquirrel:??(handle
extension is frowned upon and there is mention of buying and
cutting down a longer screw from LMS).
Mikesworkshop:??(referenced
in the above madmodder,? made his own longer screw but at end
mentions not lengthening slot in carriage [hindsight]).
Maybe if I take everything apart and pour over the above 4
threads in more detail the subtleties of the differences would
become apparent,? but instead I thought I'd ask :-)
Thanks!
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Ryan, I think that the normal size of the brass nut would not provide sufficient space to allow an insert. If you could fit a 3/4" block in the cross slide channel then maybe it could work and using the mounting screws to prevent insert rotation is a good idea.
The advantage of moving the nut to the end of the cross slide is that it enable a split delrin nut so if eventually some backlash occurs then it can be adjusted and the back lash eliminated. I have had the delrin nut in place for several years and I have never had to adjust out the backlash!!
I think it should be possible to attach a small shelf to the back of the standard OEM crosslide and then fit the split delrin nut to it.
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On Sun, Feb 20, 2022 at 04:19 PM, Tony Jones wrote:
Googling I can find lots of approaches and I'm struggling with what is considered the best approach in 2022 (ideas tend to evolve).
Tony- I just joined this group, so you probably have decided what to do in the month since you posted that question. However, I thought I would add some thoughts as I just completed mods on the compound and cross slide on my 7x14. One method that didn't make your list is the very well thought out set of ideas from 'grepper' in this post: It's well worth a read. I used his method to change the compound (I made a new leadscrew and retainer 'block', saving the original parts). It worked so well that I modified the cross slide using the same ideas. I had already 'milled' the slide to extend the travel, so the work involved making a new leadscrew and an extended retainer block with bearings, a bushing for the dial to ride on, and a key for the handle. I'm really happy with the results.
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I'll try again to post a pic of my slide mods:  Sharp-eyed readers may spot the green masking tape at the left. That's covering an opening where the motor controller box would normally be mounted - I still have the 'temporary' off-lathe controller wired to the lathe motor, even though I have the stock controller back from the repair service "Old UHF Guy". Also, I repainted the black 'drip tray' and 'backsplash' to white as it makes it easier to see the work in the chuck.
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On Tue, Feb 22, 2022 at 04:04 AM, drmico60 wrote:
The advantage of moving the nut to the end of the cross slide is that it enable a split delrin nut so if eventually some backlash occurs then it can be adjusted and the back lash eliminated. I have had the delrin nut in place for several years and I have never had to adjust out the backlash!!
I think it should be possible to attach a small shelf to the back of the standard OEM crosslide and then fit the split delrin nut to it.
I didn't move the brass/bronze (?) nut. I 'milled' the slide with my router and left the nut in the original spot. But a split nut sounds like an excellent idea for eliminating/reducing backlash.It seems to me that it doesn't matter how much space is between the two parts of a 'split' nut; the important thing is that the two nuts are 'out of sync' a small amount to tighten the fit of the threaded shaft. So adding a secondary nut at the back of the slide might be a possibility? I haven't thought through the details on this, so it may not be practical or any less work than moving the stock nut. Making a new LH nut may involve making a tap 'from scratch' if one isn't easily found for sale, so a bit of a challenge there.....
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A secondary nut at the back of the cross slide would work, but you'd need to make something to mount the nut. I've done something like this two different ways -- one for my mill and one for the cross slide on my lathe.? My mill separate-nut approach uses a steel plate bolted on to the right side of the saddle.? The plate has a hole for the feed screw to pass through, and the separate nut is threaded down the feed screw until it fetches up against the plate.? Adjusting it removes the backlash, and to fix it in place I use a piano-wire finger that fits into a hole drilled in the nut.? Here's a photo of it:  My anti-backlash scheme for the mill is very similar to the approach Sherline uses on their mills.? I saw it and adapted it to my mill so can't claim originality, other than adding something like it to my Sieg SX2 mini mill.? My upgrade has been working fine for several years.? With it I can perform climb milling so it really does take care of backlash. For my lathe cross slide I took a different approach (sorry, no photos for this one).? I cut the bronze nut in half along its width (right between the two threaded holes in the nut), then made a shim to get the nut heights to match the feed screw height. This way the nuts can be hard-mounted to the cross slide using the preexisting holes in the cross slide (this is a LOT better than the funky 3-screw OEM method).? I threaded the two nuts onto the feed screw, with a light spring in between them to remove the slack as needed -- to do that, one of the mounting screws is loosened so the spring forces the nut away from its neighbor, then the screw is re-tightened so the system can handle cutting forces without significant deflection.? This can be done from the top of the cross slide so it really is easy-peasy. I like the spring-adjustment method because all the threads will bear evenly on the screw.? A nut that is split lengthwise and tightened down will only engage the screw on either side of the split so wear is concentrated there.? My scheme is based on the spring-loaded anti-backlash ACME screws I've seen...but it should be much "stiffer" because the nuts are fixed in place when in use. Right now there's enough clearance in the nut mounting holes to accommodate the needed displacement but it wouldn't be difficult to machine a slot for more adjustment range.
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On Fri, Mar 18, 2022 at 08:27 PM, Mark Kimball wrote:
I threaded the two nuts onto the feed screw, with a light spring in between them to remove the slack as needed
That sounds like an excellent solution to removing backlash. Does the spring have the leadscrew 'inside' it - i.e. is it slid on the leadscrew between the two nuts?? Did you cut down the two halves of the 'old' nut block to give enough space for the spring, by sawing out the spot where the setscrew used to bear?
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Yes, the spring slips over the leadscrew.? I repurposed the old nut block, but did run into a problem.? I cut it on my mill with a slitting saw, but when I installed the nut in my vise I "squished" it a little bit so it didn't fit on the lead scew.? I bought a left-handed tap from LMS to re-do the threads and that worked OK, but it did make the mod cost a bit more than I expected it to.?
I bought the spring from McMaster-Carr, P/N 9434K72.? It compresses down to? .13" wide so the gap between the nuts has to be a little more than that.
Mark
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There's one small thing I neglected to mention regarding my cross slide anti-backlash modification.? I put a short set screw in the now-unused middle screw hole to keep swarf out of there.? It also could be used as a place to put in a drop of lubricating oil, if one finds the need to do so.
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