Hello :)

I've got a Sieg X1 (http://www.siegind.com/Products/br-x1-super-lathe.htm) and its seems quit nice for such a small size.

The problem I have with it is that when changing direction on an axis the handle turns a few degrees before the table moves. Its anoying. Is this 'backlash' ?? How can I stop it?

I would like to convert this to CNC, but I have no clue how, and know little about it although I've seen some projects where it has been done. I don't need 4 axis right now, 3 is fine.

Anyone have any suggestion where I can start?

Thanks :D

The problem I have with it is that when changing direction on an axis the handle turns a few degrees before the table moves. Its anoying. Is this 'backlash' ?? How can I stop it?

You can allow for it because it's probably consistant, you just have to add a little extra movement when the screw changes direction. I've done that and it worked okay, keep the gib strips fairly tight so it can't kick you out when you withdraw the tool.

To remove backlash you have to figure out where it is, is it in the nut or is it in the bearing, or both? Either way you have to add springs to take up the slack, could mean a second nut.

Best way is to fit a zero backlash ballscrew with a pair of angular contact bearings on the end, how good are you? :)

Thanks :)

How good am I? Not very hehe...

I was having a look on ebay just now and came accross this: ebay link (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130093626142&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=130093626164&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget)

Perhaps that will suit my purpose?

You can allow for it because it's probably consistant, you just have to add a little extra movement when the screw changes direction. I've done that and it worked okay, keep the gib strips fairly tight so it can't kick you out when you withdraw the tool.

To remove backlash you have to figure out where it is, is it in the nut or is it in the bearing, or both? Either way you have to add springs to take up the slack, could mean a second nut.

Best way is to fit a zero backlash ballscrew with a pair of angular contact bearings on the end, how good are you? :)


Considering its an x1 how big is your pocket book?

chris

This is really for me to try things out on. Limited budget, but only becuase I don't know if it will work :)

As far as the backlash goes, it seems to be coming from the end of the mechanism where the handles are attached. There is very very little in the threaded bar and nut.

Having disasebled it all I was surprised to find there are no thrust bearings. The ends seems to have been designed without thinking about play or friction.

I think this is the 1st problem I'll need to solve. I and make some replacement parts which can house thrust bearings, and I think that will go some way to removing the backlash.

Thanks :)

How good am I? Now very hehe...

I was having a look on ebay just now and came accross this: ebay link (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130093626142&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=130093626164&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget)

Perhaps that will suit my purpose? They do look tempting ;) You buy them and tell me how good they are :D :beer:

Thanks :)

How good am I? Not very hehe...

I was having a look on ebay just now and came accross this: ebay link (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130093626142&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=130093626164&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget)

Perhaps that will suit my purpose?

I have some of those MSD 542 stepper drivers on my X-1 with 1.8Nm steppers and it works well, though backlash is a problem. I have bought from MotionControlProducts a couple of times, and they were pretty decent. They also are on this forum and were very helpful asking my servo-related questions :)

Welcome to the top of a fun, but very slippery, slope ;)

I've decided, since I'm so new to all this, and because my milling skills are somewhat lacking, to take things a little slower :)

I've purchased a driver and a single motor from them. This will allow me to design and build some mounts and to test on a single axis before taking the plunge and getting the rest. Should it not go according to plan, at least I've not spend as much cash. :p

The motor should arrive on thursday. :)

Well I've made one mount :) Its my 1st design to see how things work out.

http://www.zen103585.zen.co.uk/rob/IMAG0004.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0005.JPG

Everything seems to fit ok

I've not found a supplier for lovejoy couplers yet but I've not really looked that hard. I made some temporary brass couplers, which make use of the keyway on the X1.

http://www.zen103585.zen.co.uk/rob/IMAG0010.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0011.JPG

Unfortunately I'm still waiting for my thrust bearings and motor driver, but I think it will work ok :)

Bear in mind this is my 1st real job on the machine so be gentle with me :p

Looks excellent to me.

Regards
Phil

Well I've made one mount :) Its my 1st design to see how things work out.

http://www.zen103585.zen.co.uk/rob/IMAG0004.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0005.JPG

Everything seems to fit ok

I've not found a supplier for lovejoy couplers yet but I've not really looked that hard. I made some temporary brass couplers, which make use of the keyway on the X1.

http://www.zen103585.zen.co.uk/rob/IMAG0010.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0011.JPG

Unfortunately I'm still waiting for my thrust bearings and motor driver, but I think it will work ok :)

Bear in mind this is my 1st real job on the machine so be gentle with me :p

Why thank you kind sir :D

I now have a fully CNC'd Y axis :D
It all seems to work perfectly well, so now I just need to make the other mounts and purchase motors for the other axis.

Hehe, didn't think it would be so pleasing to move the table backwards and forwards!!

Well I got all 3 axis working and made ran a bit of gcode i wrote on some scrap MDF.

All working nice, expcept huge backlash on Z :(

All in all, I'm disappointed with the abilities of this machine.
On aluminium, I've had to reduce the amount and speed it cuts so much that even simple parts take hours.

I guess I need to somehow make it more rigid. Don't know how yet.

You may want to consider getting the spindle rpm up and use smaller diameter cutters. This will increase the effective rigidity of the machine.

Regards
Phil

Well I got all 3 axis working and made ran a bit of gcode i wrote on some scrap MDF.

All working nice, expcept huge backlash on Z :(

All in all, I'm disappointed with the abilities of this machine.
On aluminium, I've had to reduce the amount and speed it cuts so much that even simple parts take hours.

I guess I need to somehow make it more rigid. Don't know how yet.

Well I got all 3 axis working and made ran a bit of gcode i wrote on some scrap MDF.

All working nice, expcept huge backlash on Z :(

All in all, I'm disappointed with the abilities of this machine.
On aluminium, I've had to reduce the amount and speed it cuts so much that even simple parts take hours.

I guess I need to somehow make it more rigid. Don't know how yet.

I got my 'Lovejoy' couplers from RS (rswww.com) - expensive, but you can have them next day if you want. You could also try MarchantDice.

Yes, X1 performance isn't stellar - I am trying to use it to build a larger, more capable machine, and pocketing out big holes is a very,very slow process :(

But you do get what you pay for - the X1 is cheap and at only 40kg, featherweight! You did a very nice job of those motor mounts though - it can make nice stuff if you're not in a hurry.

What part of the X-1 isn't rigid enough for you? IMHO the table is pretty solid, the column is OK but the head and spindle are pretty flimsy. I'm getting loads of chatter on my 10mm mills, IMHO and it isn't really fast enough at 2,000 rpm to run anything much smaller than 6mm bits in aluminium.

Yesterday I superglued my Z-axis gib lever tight - if you're finding loads of Z-backlash, you might try adjusting the gib until it moves more smoothly - I get lots of binding at some settings and total head wobble at others.

What sorts of cutting speeds and depths and endmills are you using BTW?

Thanks for replying :)

I'm pleased with how the motor mounts turned out :) but the Z one is certainly a major cause of the backlash. I've had to gear it down as I couldn't get the motor to move the head when mounted inline, unless the gib was very loose.

http://www.zen103585.zen.co.uk/rob/IMAG0013.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0014.JPG

http://www.zen103585.zen.co.uk/rob/IMAG0015.JPG

X and Y work well, with around 0.1mm backlash (guessed).

Yes its the head and spindle which is vibrating and chattering. It happens most when plunging. Normal cuts are not really a problem.

With 10mm end mill, I've plunged as slow as 3mm/min @ 2000rpm but it vibrates so much I get scared, and G00 Z5 as quick as I can :)

Normal cuts in the XY plane up to 1mm deep, 60mm/min full width cutting is not too bad at all with 10mm end mill.

Another problem I have, I think my motors or the powersupply is under powered. I'm running on 12v, and even the X axis won't move faster than 12mm/s. Y is limited to about 8, and I've had to set Z at 2!

Things are just soooo slow!

Your mounts are very nice looking - I can't wait to see what you'll come up with once you're CNC'ed :)

What steppers and drivers are you using? I am getting 1100mm/s in X and Y and 600+ in Z with a direct drive with. IMHO, 12v is way too low, and what sort of current can your PSU deliver?

My X-1 doesn't like plunging either - it isn't nice watching the whole head assembly skew off the vertical, is it? I tend to plunge at about 5mm/min and make sure your end-mills are centre cutting and your quill is fully retracted and locked to the fine adjustment wheel.

I probably wouldn't run a 10mm mill at 2000 rpm unless you're doing very light surfacing cuts. I've been running a 10mm 4-flute at 500 rpm 300mm/min, 0.2mm depth of cut, which seems to work well.

One thing which I think this forum needs is a bit of an X-1 manufacturing database with peoples favourite speeds/feeds/DOC for different mills and drills - the X-1 seems popular enough to warrant one :)

Your mounts are very nice looking - I can't wait to see what you'll come up with once you're CNC'ed :)

Thanks! But aren't I CNC'ed now even with the issues I have? :)

I tested a bit of Gcode on some MDF earlier:

http://www.zen103585.zen.co.uk/rob/IMAG0012.JPG

This allowed me to play with a whole bunch of Gcodes as well as shifting to polar coordinates and back to cartesian. Its a bashguard for bicycle trials bike cranks, in case you were wondering. I'll me making it in aluminium once I've sorted out the issues with the X1. :)

Steppers: Here (http://motioncontrolproducts.co.uk/product_info.php/cPath/10_14_32/products_id/80)
Driver: Alien CNC 1/8 Microstepping (http://www.aliencnc.com/aliencnc_009.htm)

Datasheets are downloadable from both links :)

PSU is a generic 12v 5Amp regulated one.

I have connected the motors bipolar series as per Alien CNC datasheet. I'm not sure if parallel would be better, but would probably let the motors spin faster. Maybe some kind people can take a look for me :)

To be perfectly honest I'm totally clueless as to what speeds/feeds/cuts to use. Remember I'm a newbie :)

It vibrates at 3mm/min with a 10mm mill at 2000rpm? Somethings wrong. You should check the ways and gibs. They should be pretty tight. I found out that allmost all the vibrations and chatter came from the gibs on the head of the mill (X2). I have now lapped the ways and tightened the gibs and now I can take 1.5mm cuts at 200mm/min (last time I did this, I got a fairly nice surface with no cooling in alu) with 60mm/min plunging using a 10mm mill. I don't think the X1 is that much weaker then the X2.

Edited for typos

It vibrates at 3mm/min with a 10mm mill at 2000rpm? Somethings wrong. You should check the ways and gibs. They should be pretty tight. I found out that allmost all the vibrations and chatter came from the gibs on the head of the mill (X2). I have now lapped the ways and tightened the gibs and now I can take 1.5mm cuts at 200mm/min (last time I did this, I got a fairly nice surface with no cooling in alu) with 60mm/min plunging using a 10mm mill. I don't thing the X1 is that much weaker then the X2.

The poor old X-1 only has 150W of motor power - mine occasionally stalls trying to put a 5mm drill through 25mm of aluminium :( The MT2 spindle doesn't seem that rigid either, and the quill mechanism can't be helping.

I would agree that the Z-gibs are a weakspot though - the gib adjustment screw seems to go all the way from locked-to-the-current-Z to floppy-head in about 90 degrees :(

Thanks! But aren't I CNC'ed now even with the issues I have? :)

I tested a bit of Gcode on some MDF earlier:

http://www.zen103585.zen.co.uk/rob/IMAG0012.JPG

This allowed me to play with a whole bunch of Gcodes as well as shifting to polar coordinates and back to cartesian. Its a bashguard for bicycle trials bike cranks, in case you were wondering. I'll me making it in aluminium once I've sorted out the issues with the X1. :)

Steppers: Here (http://motioncontrolproducts.co.uk/product_info.php/cPath/10_14_32/products_id/80)
Driver: Alien CNC 1/8 Microstepping (http://www.aliencnc.com/aliencnc_009.htm)

Datasheets are downloadable from both links :)

PSU is a generic 12v 5Amp regulated one.

I have connected the motors bipolar series as per Alien CNC datasheet. I'm not sure if parallel would be better, but would probably let the motors spin faster. Maybe some kind people can take a look for me :)

To be perfectly honest I'm totally clueless as to what speeds/feeds/cuts to use. Remember I'm a newbie :)

Sorry - I didn't mean to imply you weren't CNC'ed - I just assumed you'd made the motor mounts manually.

Looking at the stepper driver, it looks suspiciously like the one I had blow up on me, but then again all of these multi-output boards look very,very similar, and at least yours has heatsinks (advanced integrated heat management my arse!). According to the datasheet, 12v is the bare minimum you can use, and it will actually cause the board to run a lot hotter than 24v, and limit your maximum stepper power output. IMHO you need a 24v PSU with 2/3 your rated stepper current - i.e. 2/3 * (2.1A/motor * 4 motors) = 5.6A.

As for the speeds/feeds, I didn't mean I expected numbers from you - I was just thinking out loud! I'm not much less of a beginner either - I've only been doing this about 6-7 months myself.

Cheers.

150W? That explaines quite a bit. You might want to do a little upgrade to the machine, but it might end up costing more then a better machine in the end.

Out from what you just told, I would take a look at the spindle and maybe check the preload on the bearings (if the X1 is anything like the X2 this should be simple). Lap the ways of the mill with some fine grit sandpaper (Takes way to long to do it any other way and mine turned out quite good. No slop anywhere and it took 5 hours total), but make sure the gibs have a nice surface before you start.

I bet someone here has replaced the stock motor on their X1, so a little searching on that area might help you out a bit. Well you could live with those speed & feeds, but I think it sounds rediculously low.

Forgot to mention that those are some nice mounts your making. Keep up the good work!

PS. What are you planning on making with this mill? Just for hobby or are you thinking about producing something?

I've spent some time adjusting the Z gib as best I can. The vibration is reduced, but not by much when plunging.

it isn't nice watching the whole head assembly skew off the vertical, is it?

Not one bit! Thats what I mean by scarey hehe! I double checked that my end mills are centre cutting - they are. (phew! that could have made me look stupid lol)

As far as I can see the spindle bearings are ok. I cannot move it by hand or feel any wobble. I've not opened it all up for a closer look though.

Am I just expecting too much from such a little machine?

Should I use a lower spindle speed for plunging than for milling?

I've spent some time adjusting the Z gib as best I can. The vibration is reduced, but not by much when plunging.



Not one bit! Thats what I mean by scarey hehe! I double checked that my end mills are centre cutting - they are. (phew! that could have made me look stupid lol)

As far as I can see the spindle bearings are ok. I cannot move it by hand or feel any wobble. I've not opened it all up for a closer look though.

Am I just expecting too much from such a little machine?

Should I use a lower spindle speed for plunging than for milling?

IMHO, you might be expecting too much from it. What are you doing with your plunging cuts? I usually try and drill out the spot I'm planning to start my slots or pockets from, so that it plunges through air and then cuts mostly horizontally. That should work for blind holes/slots too.

I can't quite understand why a 2-flute slot mill is harder to plunge than a twist drill, but it does seem to be.

I know on my manual X2 that the column mount is the source of some of the chatter and play when milling. I have seen a small fix somewhere that beefed that mounting point up with a large washer I think. Spread the load out further to the sides of the column. You wouldn't think cast iron would twist much, but somehow it does. Not a lot, but enough to actually see when cutting deep. You may look into beefing that part up on your mill as a starting point. It's a weak point in the design of both the X1 and X2.

Little update :)

I've had a play with 24v supplying my motors and they are able to move 2-3 times faster. A good start I think, but the powersupply itself keeps cutting out. I guess its got an over current protection or something. I'll be on the lookout for something a bit more powerful. Maybe more volts too?

I'll try to pre-drill instead of straight plunging whenever I can from now on. It should be a big difference.

Kind of sad that I found myself looking at bigger mills, before I've even made anything useful with the X1... oh well...

I'm certainly learning plenty from this 'experiment' though :)

Something I've discovered is that the little threaded blocks that the lead screws go through do not appear to be aligned particularly well. When the lead screw is out far, it spins freely, but when its screwed in it gets stiffer the closer it brings the bearing block to the threaded block. I have attempted to align it, but the retaining bolts don't allow much movement. This is the case on all 3 axis.

Little update :)

I've had a play with 24v supplying my motors and they are able to move 2-3 times faster. A good start I think, but the powersupply itself keeps cutting out. I guess its got an over current protection or something. I'll be on the lookout for something a bit more powerful. Maybe more volts too?

I'll try to pre-drill instead of straight plunging whenever I can from now on. It should be a big difference.

Kind of sad that I found myself looking at bigger mills, before I've even made anything useful with the X1... oh well...

I'm certainly learning plenty from this 'experiment' though :)

Something I've discovered is that the little threaded blocks that the lead screws go through do not appear to be aligned particularly well. When the lead screw is out far, it spins freely, but when its screwed in it gets stiffer the closer it brings the bearing block to the threaded block. I have attempted to align it, but the retaining bolts don't allow much movement. This is the case on all 3 axis.

Which version of the X-1 do you have? I have the Super X1-L, and I think its size and travels lulled me into thinking it was more solid than it really is - having seen the original short table version, I do appreciate how lightweight it really is!

The sad thing is that the X-2 looks a lot sturdier but actually has less travel - the Y travel is particularly bad IMHO. I did quite a bit of looking at other mills before deciding to build a bigger one myself, and there is nothing with the Super-X1L's travels under 100kg!

Just take things easy and it'll perform pretty well!

Cheers.

Little update :)

I've had a play with 24v supplying my motors and they are able to move 2-3 times faster. A good start I think, but the powersupply itself keeps cutting out. I guess its got an over current protection or something. I'll be on the lookout for something a bit more powerful. Maybe more volts too?

I'll try to pre-drill instead of straight plunging whenever I can from now on. It should be a big difference.

Kind of sad that I found myself looking at bigger mills, before I've even made anything useful with the X1... oh well...

I'm certainly learning plenty from this 'experiment' though :)

Something I've discovered is that the little threaded blocks that the lead screws go through do not appear to be aligned particularly well. When the lead screw is out far, it spins freely, but when its screwed in it gets stiffer the closer it brings the bearing block to the threaded block. I have attempted to align it, but the retaining bolts don't allow much movement. This is the case on all 3 axis.

Hi,

I've read where many people have found they can eliminate/reduce the
binding of the lead screw by screwing the lead screw in to where the
bearing block (handle) is close to the threaded block and then loosen the
2 - M8 allen bolts that hold the bearing block to the table. Then retighten
the 2 - M8 bolts. That should help to align the bearing block and the
lead screw to the threaded block.

Mike

Yes I have the Super X1 L :) It was the Y travel that seemed to be the limiting factor on a few of the small machines I looked at.

I've done as you said, Mike, and it did help - thanks. Motor "rapids" now reaching 15mm/s X, 10mm/s Y, 4mm/s Z @ 24v volts. This is an increase from 5,5,2.

My 24v supply is a bit of a bodge, until I find a good supply at a good price :) The unit was continually tripping as its only rated 1A continuous. I've connected a pair of lead-acid 12v batteries in series with each other, and in parallel with the power supply. Any large current needed can be pulled from the batteries, while the unit can recharge them slowly. Its not ideal, but its only temporary :)

I've been reading that someone increased rigidity of the X1's column and head by filling them with concrete to increase mass!

I've now built myself a 32v PSU and have increased rapid speeds to 20x, 15y, 5z mm/s :)

I have also taken a 12v output to feed a computer case fan housed in my driver box. I'm not sure the fan is necessary but it was simple enough to do and is somewhat reassuring.

Well I got all 3 axis working and made ran a bit of gcode i wrote on some scrap MDF.

All working nice, expcept huge backlash on Z :(

All in all, I'm disappointed with the abilities of this machine.
On aluminium, I've had to reduce the amount and speed it cuts so much that even simple parts take hours.

I guess I need to somehow make it more rigid. Don't know how yet.

You might do what I did, fill the base with polymer concrete (which is basically epoxy + sand). Also fill the column with rebar and epoxy/polymer concrete. All of that, plus my Z-axis mount, tripled the weight of the machine.

See my build thread (http://www.cnczone.com/forums/showthread.php?t=36748) here for some other ideas.

Chris.