Model Engine Maker

Help! => Machines, Tools and Fixtures => Topic started by: maury on February 18, 2019, 09:02:49 PM

Title: X45 CNC upgrade
Post by: maury on February 18, 2019, 09:02:49 PM
I have an X45 converted CNC machine, and have Serious backlash. After having investigated the cause, I have come to the conclusion I need to replace the ball screws and and thrust bearings. The current ball screws are too small for that machine, and are worn. The thrust bearings are cheap ball bearings with only a mechanical tensionor. I have already replaced the balls in the Z axis with larger balls...

I have been investigating where to get the parts I need, but have had little success. The best option I have found is a kit from cncconversionkit.com. has anyone has experience with this company?

Their kit also includes the electronics, so I will probably replace that too, as the new motors will probably need more power. I can buy only the mechanical parts from them, and get new drivers, may even move up to Mach4 and suresteppers. any suggestions or help in thus area?

If anyone has any ideas or suggestions about how I could proceed with my upgrade, I would appreciate the help.

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: steamer on February 18, 2019, 09:51:14 PM
Maybe Ron Ginger can chime in here?

Dave
Title: Re: X45 CNC upgrade
Post by: maury on February 19, 2019, 09:12:41 PM
Steamer, thank you for your response.
Still looking for a source for ball screws and angular contact bearings.

maury
Title: Re: X45 CNC upgrade
Post by: RonGinger on February 19, 2019, 10:45:38 PM
When I did the lathe build class at the CNC workshop I ordered my ballscrews from a Chinese vendor on Amazon. I ordered one first as a check, which arrived in the 2 day usual Amazon shipping. Once I decided the quality was good I ordered 20 sets directly. I was amazed how easy it was. The vendor name was Ten High Electronics and Machine.

On our second batch of screws they made a mistake in machining the end. I sent a mail message and within a couple days they agreed to replace them, and the new batch arrived in about two weeks. I was amazed at that service. I will certainly buy from them again if I ever need them.

If you buy from Amazon they are bare screws, you have to do your  own end machining.

For electronics I have usually used CNC4PC.com Arturo custom built the 14 boxes we needed for the class. We used a controller by PoKey for Mach4.

I suppose I am biased, but I strongly support Mach4. It has been shipping now for over 4 years and there are lots of them out (I dont want to offer any number because I have inside information, but I assure you, its a big number) Most are going into OEM machines and many dont even show the Mach4 label. The real market for Mach4 has been the industrial world.

Mach4 requires a motion control- a small controller board connected to the PC by USB or ethernet. This now makes Mach4 a simple PC application and laptops or old desk top boxes are fine. There are several motion devices in the hobby world, Smoothstepper, PoKey57CNC, several from PMDX.com CNC4PC sells them all, as do several other vendors.

Title: Re: X45 CNC upgrade
Post by: kvom on February 20, 2019, 12:42:11 PM
I have one of the CNC mini-lathes Ron mentioned.  That said, I converted my mill from mach3 to PathPilot, and really like it.  The pulse generation is done my a Mesa card in the PC, so the mill runs more smoothly than under mach, and my rapids are faster.
Title: Re: X45 CNC upgrade
Post by: maury on February 20, 2019, 03:15:06 PM
Ron, Kvom, thanks so much for the reply. It seems most of those suppliers didn't show up on my searches. Guess I need to learn how to be a better GOOGLE hacker.

I'm working on the mechanical part first, and will look into Mach4 and PathPilot later.

I have a question about the Ten High ball screws. Are they anti-backlash adjustable? I can machine the ends, and that probably would be the best option since I haven't disassembled my machine yet and don't have the dims I would need.

maury
Title: Re: X45 CNC upgrade
Post by: maury on February 27, 2019, 09:10:12 PM
y'all, I have my machine torn down now, and am taking measurements to figure out the details of adding the Y and X ball screws. Don't have any pictures yet, probably will next post.

I have checked out Ten High for ball screws. When I removed my old ones, I found they had 2 nuts for each screw, I assume to adjust out backlash. as opposed to the ones with 1 nut and custom size preloaded balls to remove the backlash. I was able to find any ball screws on the TenHigh site with 2 nuts. After a lot of poking around I ran across AliExpress.com. They sell ball screws with machined ends and 2 nuts. Don't know id they are trustworthy, located in China. I only ordered the Y axis screw, about $60 with shipping. Will see what I get when it comes.

Motor Questions:
I have been searching motors/Drivers/power supplies. One question is whether I should wire my motor bipolar series or parallel.
Could someone shead some light on this please?

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: steamer on March 01, 2019, 12:17:43 AM
y'all, I have my machine torn down now, and am taking measurements to figure out the details of adding the Y and X ball screws. Don't have any pictures yet, probably will next post.

I have checked out Ten High for ball screws. When I removed my old ones, I found they had 2 nuts for each screw, I assume to adjust out backlash. as opposed to the ones with 1 nut and custom size preloaded balls to remove the backlash. I was able to find any ball screws on the TenHigh site with 2 nuts. After a lot of poking around I ran across AliExpress.com. They sell ball screws with machined ends and 2 nuts. Don't know id they are trustworthy, located in China. I only ordered the Y axis screw, about $60 with shipping. Will see what I get when it comes.

Motor Questions:
I have been searching motors/Drivers/power supplies. One question is whether I should wire my motor bipolar series or parallel.
Could someone shead some light on this please?

Thanks,
maury

What you want is the ball screws that Ron directed you to.   that's the way to go.

Dave
Title: Re: X45 CNC upgrade
Post by: Admiral_dk on March 01, 2019, 11:34:56 AM
The wiring depends on the motor and speed controller you hook it up with - the manual should give the info you need.
Title: Re: X45 CNC upgrade
Post by: maury on March 01, 2019, 02:53:24 PM
Steamer, thanks for the reply. I trust Ron's expertise, so I am inclined to go with the Ten High. But, the screws I removed from my system had two nuts. Backlash is the problem I'm trying to fix, so I would like to understand why it's better to go with a ball screw with one nut as opposed to one with 2 adjustable nuts.

Admiral, also thank you for your response. I have read the manuals for the motor drivers and for the motors. they have a very light discussion about the options for wiring the motors in parallel or series. The motor drivers will work either way, and are programmable for the correct current. The only indication I have been able to find balancing the two is there is a little more torque at same speed for parallel connection vs series connection. It also takes more current. Again, I'm trying to learn here and a bit more detail would be helpful. Maybe it's just the engineer in me trying to get out.

maury
Title: Re: X45 CNC upgrade
Post by: steamer on March 01, 2019, 04:17:18 PM
Ball screws are generally preloaded so a second anti backlash nut is  not required.
Title: Re: X45 CNC upgrade
Post by: RonGinger on March 01, 2019, 07:39:03 PM
I have used both one and two nuts. On the lathe class with the Ten High screws we only used one, partly for simplicity, partly low cost. They were also 'good enough'. That last one is a very scientific term.  ::)

For my own mill- a Jet knee mill, I used cheaper screws and did back to back nuts. They have been a problem, the Y nuts gets loose and it s a real bear to get into to adjust. I really should replace them now that I know a better source.

Its hard to do a real accurate measurement, but I felt like the lathe screws were in the .001 range of backlash. I think a lathe can stand more backlash because you almost always make cuts in the same direction. Mills need to be better because you are always changing direction.

All ballscrews are not all pre-loaded. Its the old pay for quality game.
Title: Re: X45 CNC upgrade
Post by: Admiral_dk on March 01, 2019, 07:43:23 PM
Well I honestly haven't experimented with these things .... but I'm guessing that it isn't that difficult to change the wires from one to the other - it might take much longer to change the parameters in the controller. For this reason alone I might try them both - unless I was so satisfied with the first try, that I couldn't care about any improvements.

Best wishes

Per
Title: Re: X45 CNC upgrade
Post by: maury on March 02, 2019, 05:00:01 PM
Guys, thanks a lot for all the help. I really appreciate it. I'll try to keep the thread up to date as I progress and share what I have learned.

Since I already ordered the Y ball screw, I think I'll do the Y axis with it and see how it works. Ron, I agree the double nut version can have the problem of coming loose and needing adjustment. Also, it's a pain to re-adjust, hope the design has improved on the screws I ordered.

I also ordered the motors, angular contact bearings, and most of the electronics and boxes. So the process begins. I will be able to reuse some of the motor mount brackets, saving some time there.

The old design used a belt drive for the ball screws, with a 2:1 ratio. Since this is a fairly heavy mill, the torque increase will be welcome. I believe I can still get about 40in/min for the rapids. anything faster than that scares me, plus most if my cutting has been less than 15 in/min anyway.

BTW, a really neat find I ran across at the ball screw site is I can order new bellows for the ways, and they have sheet metal coil springs for protecting the ball screws. Javen't figured out a good way to oil the ball screws yet.

maury
Title: Re: X45 CNC upgrade
Post by: Neil-Lickfold on March 02, 2019, 08:10:26 PM
In the real world, is there a lot of difference between the C7 or C5  ball screws compared to C3 grade ball screws? Those that have made the conversions, what sort of precision is achievable with these converted cnc mills?
I have a mill and are thinking of  the cnc conversion myself, but not sure of the real world advantages for the home shop that is mainly making 1 of something.
Neil
Title: Re: X45 CNC upgrade
Post by: RonGinger on March 02, 2019, 09:00:38 PM
Quote
I have a mill and are thinking of  the cnc conversion myself, but not sure of the real world advantages for the home shop that is mainly making 1 of something.
Neil

I hear this a lot. Suppose the one  piece is a curved spoke flywheel? Or maybe a Stevenson link. Things like this can be setup and run at one pass, maybe taking a half hour or so. I suspect you couldn't even get the rotary table set up for i ts first cut in that time.

I will admit it can take some time doing the CAD and CAM, but its still a lot faster on CNC. And speed alone may not be that important,  its a tool that lets you do vastly more complicated parts you probably wouldn't even try without it.
Title: Re: X45 CNC upgrade
Post by: kvom on March 02, 2019, 10:26:42 PM
Replacing the rotary table for any curved profile is the first obvious advantage.  I sold mine after not using it for a couple of years.

Thread milling studs is much easier and faster than single-point threading or using dies.

Engraving.

Manual machines still get plenty of use alongside.
Title: Re: X45 CNC upgrade
Post by: Dave Otto on March 02, 2019, 11:42:30 PM
Also, when it comes to 3D surfacing there are things that you can do with a CNC, that would be pretty hard to do on manual machines, if not impossible.
Attached are a couple pictures of the intake valve body that I made for my Pacific Vapor Engine using 3D tool paths.
Not saying this part couldn't be made by other means, many have; just trying to show some of the fun things you can do with your CNC mill. ;)


Dave
Title: Re: X45 CNC upgrade
Post by: Jo on March 03, 2019, 08:06:49 AM
I always think bits like that are really impressive Dave but I wonder how long they take to make  :noidea: .

If I made that I would make 3 bits and silver solder them together which would probably take a couple of hours... so how long from start to finish did that take to machine? ( Lets assume that the part is already drawn up in CAD and that the CAM tooly planning bit took zero time  ::) )

Jo

Title: Re: X45 CNC upgrade
Post by: Jasonb on March 03, 2019, 08:18:46 AM
Jo, to some extent you can let the CNC machine get on with its own thing leaving you free to work on other items or just fondle castings. Also none of those dark silver solder lines you keep moaning about when others use soldered fabrications. Plus with spindle speeds of 5000rpm or so the tools can be fed much faster than with old iron machines so the cuts don't take as long.

By way of example this is one of John S's start to finish including drawing and producing the code 40mins :)

(http://www.stevenson-engineers.co.uk/files/flywheel.jpg)

Having just got a CNC machine I can already see uses for it that would be far easier than doing by hand. The Forest Style engine that I'm working on at the moment has several parts that would have been ideal for this and saved many setups with the rotary table or working with co-ordinates. I've already got my name on the list for a new engine design which the drawings should be ready for later in the year, 3 parts on that are crying out to be CNC cut one of which is a wavey spoked fltwheel.
Title: Re: X45 CNC upgrade
Post by: Jo on March 03, 2019, 08:34:32 AM
I can see lots of uses for one but its like 3D printers if it takes hours and hours to do the printing/machining  :Doh:
And I know Mike's CNC mills like to add little features to make his parts unique so he still has to keep an eye on them ::)

And the original over 4 grand needed to buy even the little Seig one  :paranoia: You could buy a decent mill and convert it for that sort of money  :thinking:

Jo
Title: Re: X45 CNC upgrade
Post by: Jasonb on March 03, 2019, 08:48:24 AM
I can see lots of uses for one but its like 3D printers if it takes hours and hours to do the printing/machining  :Doh:
And I know Mike's CNC mills like to add little features to make his parts unique so he still has to keep an eye on them ::)

And the original over 4 grand needed to buy even the little Seig one  :paranoia: You could buy a decent mill and convert it for that sort of money  :thinking:

Jo

But how many hours to do something like that brass flywheel manually, could you draw and machine that in 40mins?

ARC are doing the small Sieg for just under £3k and giving others away! Yes you could convert something for less but for those not into all the electronics the ready made machines are plug and play. Also you get things like much better bearings and spindle compared with the similar sized manual machines as well as a lot more subtle differences such as reprogrammed chips to get the best characteristics out of the brushless motors at speed which you don't get just by sticking ball screws and steppers on a standard machine. Also the KX1 is nothing like a X1 mill under the outer casing.
Title: Re: X45 CNC upgrade
Post by: Jo on March 03, 2019, 08:55:09 AM
If someone was to give me one.. I would pay the postage  ::) And I do understand the electronics  ;)

£3K is a lot of casting sets  :pinkelephant:

Jo
Title: Re: X45 CNC upgrade
Post by: Jasonb on March 03, 2019, 10:34:24 AM
I'll carry this on in my "Going over to the dark side" thread rather than hijack this one any more.

http://www.modelenginemaker.com/index.php/topic,8882.0.html
Title: Re: X45 CNC upgrade
Post by: maury on March 06, 2019, 08:18:38 PM
Guys, lots of great discussion on why to use a CNC in your shop. I always believed in using the correct tool for the job, and have found CNC fills the bill for the more complex parts. Even simple ones like cutting a lever out of sheet metal.

So, a lot of the electronics has arrived, and I have bought a Windows 7 computer to upgrade my old XP box. I have downloaded the Mach4 trial version, and I think I'll like it. One thing I noticed, but was able to fix was the tool table size. I have a tool numbering scheme that uses 256 numbers. Fortunately I was able to configure the Mach 4 tool table to 256. That would have been a killer.

Now for the second killer question. I used the nesting feature in Mach3 more than a few times, and I can't do without it. I don't want to buy nesting from BobCam.

---- Is there a nesting wizard for Mach4? ------

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: Neil-Lickfold on March 06, 2019, 11:34:36 PM
What is the difference between using C7 ball screws and C3 ballscrews?  Apart from cost?
Any info will be appreciated.
Neil
Title: Re: X45 CNC upgrade
Post by: maury on March 06, 2019, 11:46:58 PM
Neil, if I understand correctly, the difference between the C grades of ball screws is the accumulated error with length. (rolled ball screws) So, a C3 ball screw would be a lot closer at say 6" from zero then a C7 would. It depends on what you are trying make. I think most hobby mills are fine using C7. If you are trying to make large professional parts, C5 would be better. C3 would be even more accurate over length.  Look at the specs.

Ground ball screws will be more accurate over the shorter lengths.

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: Neil-Lickfold on March 07, 2019, 03:21:05 AM
With the C7 and C5 the specs look terrible to me. If trying to make parts to 0.02mm can they be tuned to be able to do that on the C7 or C5 ballscrews? Or do I need to have C3 or better? Looking to be able to achieve better than 0.02mm over a 280mm long part with a home machine.
Title: Re: X45 CNC upgrade
Post by: kvom on March 07, 2019, 11:44:35 AM
(http://Looking to be able to achieve better than 0.02mm over a 280mm long part with a home machine.)

I would say you are dreaming.   :disagree:
Title: Re: X45 CNC upgrade
Post by: Jasonb on March 07, 2019, 01:24:28 PM
Or better start saving up for a Haas
Title: Re: X45 CNC upgrade
Post by: RonGinger on March 07, 2019, 02:09:51 PM
Quote
Now for the second killer question. I used the nesting feature in Mach3 more than a few times, and I can't do without it. I don't want to buy nesting from BobCam.

---- Is there a nesting wizard for Mach4? ------

Thanks,
maury

What did you use in Mach3?  I do the support for the Mach native wizards and I do not know of nesting. Likewise we  have not done a nesting wizard for Mach4, although Brian is working on a special plasma package and that may have some nesting. I will find out.
Title: Re: X45 CNC upgrade
Post by: maury on March 07, 2019, 03:37:19 PM
Ron, thanks for the reply. The wizard I use is called "Nesting" in the wizards menu. It is by Oliver ADLER.

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: RonGinger on March 07, 2019, 07:59:57 PM
OK, those were user contributed and never  supported by Mach. I do not know of any similar program, sorry.
Title: Re: X45 CNC upgrade
Post by: maury on April 01, 2019, 04:33:43 PM
Folks, it's been a while, and a lot of work has gone into the project.  I want to thank all the
responders for their comments and help. So here is an update.

I ordered the "Y" ball screw directly from the factory in China. Didn't know what I was going
to get, but it was only a little more than $30, so I just took a gamble.

In the mean time, I ordered the electronics and motors, and set out making the panels.

Pic1 is the whole system torn down.

Pic2 is the start of making the motor control panel. After everything was laid out I drilled the
holes, sanity checking the fit into the box.

Pic3 is the motor control panel with the parts mounted and beginning of the

Pic4 I'm laying out the power supply panel.

Pic5 is both panels mounted to the machine. most of the wiring is complete.

Thanks for tuning in
maury
Title: Re: X45 CNC upgrade
Post by: Vixen on April 01, 2019, 07:46:53 PM
Hi Maury,

That looks like a very tidy electrical installation.  :ThumbsUp: :ThumbsUp:

When do the mechanicals arrive?

Mike
Title: Re: X45 CNC upgrade
Post by: steamer on April 02, 2019, 12:17:22 AM
[quote

All ballscrews are not all pre-loaded. Its the old pay for quality game.
[/quote]

Yes im sure you can get ballscrews without preload...but why would you.   

Dave
Title: Re: X45 CNC upgrade
Post by: maury on April 18, 2019, 10:18:03 PM
Guys, thanks for the comments.

It's been a while, and a lot has happened.I have refinished most of my back deck and have started
planting flowers in the many pots I have. Started a lot of them from seed. The garden is in,
and the tomatoes and peppers are starting ot bloom. So, in my spare time I worked in my CNC project.

I am using ball screws with two nuts which are adjusted to squeeze against each other to remove
the backlash. We'll see how that works. The Y axis is all done, and the X axis is also in except
for wiring up the motor. I also painted the walls in my shop while I had everything torn up.

The electronics/wiring is all done, so, since the Y axis is all done I wanted to fire it up and test
what I have so far. I am currently using Mach 3 because I have a license and it does nesting.
I may move to Mach 4 in the future,but it's not priority right now. I was able to get Mach 3 and
the ESS configured, so I went fro broke and connected the big power supply to the Y  motor driver.
Everything was smooth so far.

So what I observed when jogging the Y motor was an erratic behavior. The jog was .001. As I jogged
the motor it went in one direction on the first jog, then reversed direction on the second jog, and
alternated with each additional jog. If I up the jog to .010, the behavior was motr random and jumpy.
I spent a half day checking the wiring and documentation, and have come up with no explanation.
I am probably going to need some help with this. I can post the details of what I have and all my
configuration data if there is someone who can help debug this problem. I appreciate any help.

Here are some pics of the progress. The 10mm tap came in today, so I can finish the mechanical on
the Z axis.

Title: Re: X45 CNC upgrade
Post by: maury on April 20, 2019, 02:33:04 PM
Well folks, I found the problem. After a near sleepless night thinking about what could be wrong I came up with a few more things to check and re-check.

I was poking around when I decided to check the motor connector with an ohm meter. One of the windings seemed open - BAD. So I rechecked the wiring with the motor document. Well, there it was. I misread the drawing. Fixed the problem and the motor worked great. I connected the X motor and re-tuned both. They are very robust and smooth running.

Now, I',m working in the Z mechanical. Hope to get the Z and A working in the next week.

Happy Easter
maury
Title: Re: X45 CNC upgrade
Post by: maury on April 20, 2019, 10:27:33 PM
The Z axis is in now too. Motor working properly. Just need to mount the head and counterweight and I can test out the machine.

I have a config question:
in the Port setup dialog there is a Kernel speed setting. Does anybody know what this does, and how I may set it to my best advantage?

Thanks,
maury
Title: Re: X45 CNC upgrade
Post by: Neil-Lickfold on April 20, 2019, 11:54:24 PM
When people add a gas strut for the Z (head counter balance), what spec or model number do they use?
I don't want a weight going up and down the back of the machine.
Thanks,
Neil
Title: Re: X45 CNC upgrade
Post by: kvom on April 21, 2019, 12:40:40 PM
The Z axis is in now too. Motor working properly. Just need to mount the head and counterweight and I can test out the machine.

I have a config question:
in the Port setup dialog there is a Kernel speed setting. Does anybody know what this does, and how I may set it to my best advantage?

Thanks,
maury

I believe that's used for the pulse rate when using parallel port interface.  With ESS pulsing the value is ignored.
Title: Re: X45 CNC upgrade
Post by: maury on April 21, 2019, 01:58:52 PM
Thanks KVOM, that simplifies things a bit.

As far as picking the gas struts goes, my machine has a counterweight on the back. I know it's a kludge but it works. Its not an exact balance, there is still some weight in favor of the head. You will need to get the weight of your head and pick a size that works. Not much help, but every machine is different.

maury
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