Replacing V Wheels with Linear Guide bearings

It look like they will have kit up to 39" travel in X and 52" travel in Y, it’s really bigger than a 1000 Xcarve who is ±32" travel in X and Y

Interesting I stumbled upon this thread, I am in the process of adding linear rails now. Rails ordered, picking up new plates tomorrow.

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Did you go for the MGN15 or HGH15?

MGN12 15 wouldn’t retrofit.

Looks good. Is there any concern with trapping debris on the lower rails?
I’m unfamiliar with how well they stay sealed against chips and dust over time.

I need to model my setup as well.
I’d like to add linear rails in the future, but I figure at the same time I’ll upgrade the extrusions also.
So linear rails, extrusions and endplates all at once.

The biggest opportunity for contamination is the top rails, where debris can collect in the screw holes and make their way into the carriages. I will probably seal up all the holes, and the carriages have wipers on both ends, so hopefully that will eliminate any issues. I’ve yet to find actual plastic plugs made for these rails, so I may end up using modeling clay or maybe silicone to fill the screw holes. I also intend on some sort of side shield to cover the carriages (yet to be designed).

After a full year of running my Z-axis with the same linear rails and no attempt of plugging the screw holes, the carriages did become contaminated, but easily cleaned with WD40. I will probably re-clean & seal those holes at the time of my rebuild.

Google for “Hiwin dust caps”. Different rail sizes take different cap sizes. If using clones, double check your measurements.

…deja vu. Look at comment #24 above.

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I opted to skip the retrofit when I found out 8020 40mm bars were $20 @ 1000mm. I would love to see a closer look at the plate you have inside the x carriage. Do you plan on going official HIWIN? Did you have someone cut your plates or did you mill them yourself?

This project is sort of a two-pronged approach. Since my machine is very custom, I optimized the design with new side plates. I also bought new sticks of 20 x 40 to replace the Y makerslide. Not out of necessity, as the rails will work with existing makerslide, but because I’ve damn-near completely cloned my machine at this point. I can reassemble & sell the “original”. As far as going with official HIWIN, that will depend on the supplier. I’m working in conjunction with @LukeWilson and he is the sourcing specialist, so whatever he comes up with.

The 2nd prong of this project is to develop it as a true retrofit that someone could add-on to an existing TBD screw-drive upgrade (oops, spoiler-alert). I’m still in the design stage of this aspect of the project. The X axis is not proving to be as “upgrade-friendly” as the Y axis. Still fleshing out options here. The wide makerslide will not be usable to upgrade, due to its lack of slots. And dimensionally, it may not be feasible to keep the existing side plates.

I don’t mess with making my own plates, since I can have them laser cut where I work. For this round, I’ve opted to go with 3mm high-strength steel on the plates.

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Any updates?

Yep, running smooth now!

BEFORE pic :laughing:

AFTER pics :sunglasses:

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whoaaaaa bill. that’s awesome haha

specs on the rails?

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welp, I’m super jealous now. I’d really love to get some more detailed pictures and maybe (with your generosity, of course) some design files. I want to hear how it’s working, and what it’s capabilities are. I am seriously wanting to do this conversion and anything that saves me time and trouble is most genuinely appreciated.

I see you’re still running what looks like the factory steppers. I’m using 270oz steppers, and that inboard configuration makes me think you might lose a substantial amount of X travel with the longer steppers. Is that the case?

That is a massive increase in rigidity :rofl:

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I’m hoping to have this kit (the linear rail upgrade) available within the next week or two. My laser shop had some brake press issues that delayed us receiving the parts.

Regarding the inboard config of the motors, you may lose 1/4" or so with the 270oz steppers, but there’s a surprising amount of room back there. Bill’s original design has evolved into a kit that can accomodate direct drive or inboard belt drive on all 3 screws, so assuming you have space behind your machine stepper length isn’t an issue.

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Thanks guys!

@PaulAlfaro, those are MGN12 series rails & carriages.

@Pyrex, would love to get you more pics.Might be a minute, as I’m in the process of building a new controller and need to focus on getting it back up & running. I can’t speak to the full capabilities, but I did cut some aluminum using a .125 end mill, depth of cut .060 @ 35 ipm. Probably could have pushed it harder, but I tend to run conservatively. I did this mostly for increased accuracy & repeatability. I didn’t lose any travel with my motor inboard, being the smaller motors. I have no plan of upgrading motors because the screw drive gives me a 10x increase in power anyway.

@HaldorLonningdal lol, it’s rediculous now! Doing a rather unscientific test with a dial indicator placed on the spindle nose, I previously had +/- .008 - .012 (both sides of zero, so total was .016 - .024 tir) by placing lateral force against the frame. This force was placed lateral to the v-wheels in both directions. After the linear rail upgrade, the same forces measured +/- .002. I was pretty happy with that!

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My biggest concern is the increased rigidity of a linear rail system might be lost attached to such a flimsy X axis, almost seems like the appropriate time to change to a considerably beefier gantry. (on the 1000mm machines, smaller machines like a 500mm or 750mm would probable be adequate)

True that it would be nice to upgrade to something more substantial, but where do you finally draw the line before you’re building a completely new machine? This kit was developed to offer an upgrade path without building a whole new machine. A modified x-carve (light-duty machine) will never be as good as a properly designed medium-duty machine, but a screw drive and linear rails can move the machine to the top of its game.

All I can say is WOW. I have futzed with some designs and looked at different options to build a stronger version of the 1000mm X-Carve for some time - as the V-Wheels are perhaps the weakest link in the system. As I worked through the design - moving to lineal bearings the extrusions became the weak link, then the belts and the motors. Before long it was move to a whole new machine. As I totaled up the costs I was getting to the cost of a Precision Matthews PM30 bench mill to do the work in Metals that I want to do. So I dropped the money on that and will create a CNC kit for it - and then build the new gantry system. Still thinking about what will be left of the X-Carve after that is done - and arrived at “not much”.

Looking at all of the posts and project above, I am blown away by the work. Bill Blades - that is an incredible build! Perhaps by cloning the X-Carve unit I can resell it too - nice idea. It could be a good project to get my Robotics Team kids involved in - let them make a new gantry CNC for the team. Hmmmm.

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@DavidSchneider, thank you so much for your kind words! Having been a machinist/toolmaker for the first half of my career, and a tool designer for the second half, I have a pretty strong grasp on what will work, what won’t, and what’s worthwhile doing. I completely agree, that upgrading the x-carve can be a slippery-slope. And I did exactly what you proposed after I had completed my linear rail upgrade. I had so many original x-carve parts that I found myself at a crossroads: either sit on a stack of x-carve parts and extrusion that I would not use, or buy a few more components to basically “rebuild” the original x-carve and sell it, which is exactly what I did. I ended up putting together a reconditioned machine with all new electrics (less the x-controller) and sold it for a tidy sum.

I would still like to get a small bench mill at some point, as it has certain capabilities that the x-carve can’t begin to touch.

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