Been searching around for just this, bought my 1510 back in January and have been completely frustrated with the non-stop wheel adjustments and just when you think you have it perfect it goes out again after a short time cutting, pretty much every time from what I can tell it starts binding and causing the Y axis to go out of whack. I am doing some larger pieces of acrylic with some detailed etching, when I do a small piece I have no major issues but once I try to run on a 48" piece and the Y axis has a lot of travel it is very problematic, a 1 or 2 mm mis-alignment will destroy the entire job and there goes a $200 piece of acrylic. I slowed the machine right down to try to reduce this, which helps a bit but still need to find a better solution and takes forever running at slow speeds and need it to run faster to get a cleaner etch, get a lot of back-fill when running slow, which means hrs with a Dremel after cleaning it up, which I was hoping to not have to do.

After spending as much as I have already I am approaching this cautiously, so I plan to start with changing out the Y axis wheels with the linear bearings as you have shown but keep the belt drive for now. I see you changed yours out to screw driven as well, was the belt drive still problematic after you installed the linear rails? Did you use slide in nuts in the C beam to secure the rails or did you drill and tap the linear rails to the C beam?

I was also curious about the X axis mod, did you use the same rail and just cut it down or did you order a different rail?

I really need to get some consistency to this machine and spend more time cutting and less time adjusting, seems so far I spend more time setting the machine up then cutting with it.

Interested in the mod kits as well, did you start producing them? It would be great to have a little more clearance, hoping once I get converted to the linear rails to make that mod as well.

Looking forward to making this conversion, hope it helps resolve many of the issues I have been having so I can spend more time reliably cutting.

 

So, it seems to have worked well. Just one quick cut in aluminum for now, but seems much more rigid than before. Although there is still some play on the x axis when pushing the router by force. Guess the whole x axis c beam is still twisting a bit.
Will test more by milling some new corner plates to rise the workbee after I get back home in 2 weeks.

 

Thanks for the suggestion, I will try it. I have installed the linear rails on X and Z only for now. I'll upgrade the Y later.

 

No problem,I started with those as they seemed much more challenging than the Y . As for the play, it only happens a bit when pushing on the router in the Y axis direction (z axis fully extended). I tested it in the middle of the gantry. In the X direction it is rock solid.

 

This is why I don't advocate using OB C-beam in designs over 1000mm axis length. The C-beam is just not stiff enough, particularly if you want to machine aluminum. That and the belt drive makes the 1500mm machines very poor performers. I refuse to sell them at all.

You need an X axis that is WAY stiffer than a c-beam can provide. With the linear bearings, you could add a second c-beam behind the main one since you no longer have the rear gantry plate. You would have to figure out a good way to connect them together to increase the stiffness.

MG

 

Well the backplate is actually still there as the backslash nut is attached to it. I was thinking of relocating the acme screw to the top and attach the backlash nut to the top linear guide L bracket. Then it would be possible to remove the backplate and either add another c beam or an aluminum or even steel plate on the back of the existing c beam. I can't remember exactly, but someone modified an ox this way. It should be on the openbuilds forums.
I have the 1000 x 1000 leadscrew version, and generally can't complain except for the problem stated in previous posts.
I did some aluminum cutting before the upgrade, it is not perfect, but so far acceptable for my purposes. Of course I would not complain if it was better

 

I am going to make some similar mods to my Workbee 1515 that I am cutting down to a 1510. I have a question about your Y-axis lead screw bearings and retainer. It looks like your bearing is on the outside of the Y-axis end plate(s). I am curious if you are only using the outside bearing, or are you perhaps using a second bearing on the inside of the Y-axis end plate?



On the motor side I am curious if you are doing something similar with the bearings. I can't tell from any of your photos, but it almost looks like you are leaning on the coupler to support the entire threaded rod.



Great build. This has given me direction on how to clean up a lot of the bad behaviors I get out of my machine.

 

Thank you for the information. Anything you would change about the bearing mounts?

I saw your images of the plates you cutout, that looks super solid.

 

Hai there openbuilds members.. i just need a suggestion on linear rail type for y axis workbee CNC, is it ok if using HG guide rail type? I found a good price for HGR15 type but i just wanna ask the professional before i buy the rail.
Thanks in advance

 

Quick question on this build - do you have measurements on the locations you drilled holes to mount the blocks for the gantry plates? Or was this a little bit of "point and pray" with location drilling?
Thanks!

 

I saw the drawings for the bearing blocks and the hole locations, I must have missed the one for the plates. I'll check again after work.
My hgh rails are showing up today, but have to order more blocks and the hardware. Mods to come soon!

 

Got my final linear block done this morning (sneaking parts in between runs at work lol) so I was wondering if anyone had tips to set the linear rails on the machine, placing blocks, drilling etc.
Thanks for any info!

 

Nothing?
Ok, guess I'll just try to figure it out.

 

Thanks Sharmstr, appreciate the info!
Would you happen to have the dimensions you used to drill the bolt holes for the Y plates to attach? Or would you happen to know if there are there resources for CAD files on the XY plates for the locations of the holes?
I'm guess I'm too used to working with prints..so I get hazy when freewheeling.
Sorry for all the questions

Made a quick paint sketch - the info I'm looking to glean is side mount hole locations like the ones circled.. I can't find info in the CAD section about any of the main axis plates, that's why I ask. Maybe I'm looking in the wrong place?

Dropbox - example.jpg - Simplify your life

 

Oh no worries, I understand that life happens.
If anyone could point me to prints for the axial plates so I could tell where to punch holes to mount the linear blocks I'll happily head that direction.
That's the only thing that's holding me back from being able to continue upgrading.
Something I could open in solidworks to dimension would be perfect if available on here somewhere.

 

Perfect! Thanks sharmstr, I'll check these out at lunchtime!

 

Where did you guys source the lead screws and linear bearings from? The link from the parts list has the linear bearings sold out. I am fed up with these belts and wheels. I have a bunch of aluminum that I can use to reinforce the machine and make it more rigid once I get some decent bearings that don't break the bank.