Lowrider CNC

[jhitesma]

Well, remembered to measure my spare door today...and it's 36". Which according to the calculator means I could get 26" of working area out of it...so big enough to fit 20" sheets. Hmmm....Would be kind of neat to build it wide enough to do a bit more than 60" wide and cut two sheets at once.....

So maybe using that door is worth looking into. I also looked for rails today but didn't have my calipers with me so wasn't able to actually measure anything. Got a lead on a few local metal suppliers I can call this week to get quotes from though.

Printing is almost done. The last "big piece" is about 2 hours from finishing. Then I just need to do the last set of big spacers and tension cones...and a last set of wheels Bearings should be here tomorrow so will probably have it fully assembled other than tubes/motors/electronics/belts this week. Will be a few more weeks until I can get the rest of the bits though.



Looking at the parts though...I found it odd that two of the supports on the 611 plate are cut out to fit the 611 router...why not just center the router? I don't really see any good reason for doing it the way Ryan has...I may have to ask him about that.

I also noticed...there's a lot of open area on the 611 plate. What if...instead of removing the 611 and mounting the "enterprise edition" cutter in the 611 hole....what if you just mounted a more standard cutter right to the plate and used the plate itself as the insulator. Well, one issue there is the plate is currently just MDF and I wouldn't trust MDF to hold the guide. But I can cut a plate from ply and use that instead.

The cutter looks like it could fit:



That's mounted where the holes are for a second motor which Ryan drew in but later decided wasn't necessary. But I'm not sure if it would clear the rails in that position. May have to add some holes closer to the edge. Could easily do a version of the cutter without a mount and just add some m3 mounting holes in the base instead.....

Hmmm....may have to fire up onshape tonight and do some experimenting....

 

[moebeast]

If the tube is in the way, maybe turn the cutter around so the needle is off the edge.
For a dedicated foam and vinyl cutter, the plate could be much smaller to save footprint. If a 36" door will give 20" cutting, and you have one, I would go as is and have the router option. On the other hand, 4x8 is my dream for building kayaks and other plywood boats.

 

[rockyboy]

I like the idea of having it waiting there on a separate location from the 611 - would make changing tools and calibrating a whole lot easier I think.

I just finished printing the last part for one of the side carriages a few minutes ago. Still need to print all the parts for the second side carriage, and the LCD holder. That will probably take all of next week to finish up.

But in other good news, my shop is finally cleaned enough that I have a space to build and put it! :applause:

 

[jhitesma]

If the tube is in the way, maybe turn the cutter around so the needle is off the edge.
For a dedicated foam and vinyl cutter, the plate could be much smaller to save footprint. If a 36" door will give 20" cutting, and you have one, I would go as is and have the router option. On the other hand, 4x8 is my dream for building kayaks and other plywood boats.

Yeah, I really want a machine that can handle full sheets of 4x8 for other reasons. But while I'm at it I kind of want to test the lowest cost easiest way to build a dedicated foam cutter as well just to help others who aren't interested in cutting 4x8 sheets.

I posted on the vicious forum asking about the offset on the 611 and found out that it's to give room for the vacuum shoe attachment. So yeah, a dedicated foam cutter could use a much smaller tool plate. (and the spot I was thinking I could put my laser isn't such a great spot after all since that's where the dust shoe fits!)

I also realized the issue with mounting the needle separately is the needle guide projecting down would interfere with using the router unless you remove the guide. So a separate needle mount would have to have a quick connect/disconnect shoe of some kind.

Which brings me back to my original idea of building the needle cutter so it can fit inside the 611 base and use the 611 base quick release. Eyeballing it I didn't think it would fit...but one of the posters on vicious1 brought it up so I opened onshape and measured....and it's actually viable. The back of the cutter to the front of the guide hole is 50mm which leaves 20mm of space to work with. There may be some issues with clearance for the flywheel...but that could be shaved down a few mm if necessary. The only other catch is the needle won't be centered in the 611 base but that's no big deal. So...I'm going to play with some cad tonight and see if I can come up with a way to fit the cutter inside a 70mm tube that can clamp into the 611 base. I have an idea on how to do it already...

 

[jhitesma]

Another interesting approach to mounting things on the low rider:
http://www.vicious1.com/forum/topic/im-working-on-a-dw660-mount-for-the-low-rider

Maybe I should finish up my 525 mount needle cutter revision.....wonder if it would stick out too far though...

And wouldn't make it easy to put the 611 on. So I think I'll still keep looking into making one that can fit inside the 611 mount...

 

[rockyboy]

It's an interesting idea, but as you point out it still doesn't address using the 611 as a quick switch tool. I think your idea of putting it fully inside the 611 mount is the way to go - if we can figure out how to cram it all in there...

Still printing over here... estimated 20 hours or so of printing left for all parts...

 

[jhitesma]

Other than the other set of wheels I'm done printing Well, I have a few little things left because I was waiting until I swap back to the Raptor PLA to do them. But...probably going to be a few weeks until I have a budget for tubes/steppers/belts/idlers...so things are going to slow a bit at this point.

Speaking of wheels though, I finally uploaded the video I shot last week of the first set:

I need to make a few adjustments to them. The bearings sit a little too deep so they rub. I also made some printed spacers to go inside since I don't have metal ones - I'm thinking by making those spacers a little longer I can push the bearings out and re-use the existing prints. But I may have to make the wheels a few mm narrower overall. We'll see.

Tempted to call some local metal suppliers tomorrow...but really don't have cash for tubes this week so probably shouldn't just yet.

 

[rockyboy]

I was able to get one of the side carriages together tonight! :applause:



If it looks a little rough, that's cause I built it by hand after gluing a template to the MDF. I did screw the two sides together and do all the drilling and scroll saw work at the same time, so things line up pretty good - hopefully I'll be able to get enough accuracy out of this build so it can cut itself some better parts if I need them.



Back to watching the printer go... only have 4 parts of the other carriage completed so far. *sigh*

 

[moebeast]

I've been playing around in Fusion360 thinking about the smallest, cheapest 20"x30" dedicated foam cutter. This is the Low Rider style carriage I came up with.



Moving the Y-stepper to the side plate would make it more compact.

Next, I'm looking at putting Z-axis on the carriage for simplicity. I'm looking at CD-ROM mechanisms and 3D printer parts. I want it to use readily available parts.

 

[jhitesma]

Neat mobeast. Just a few thoughts....

For a dedicated foam cutter you only need about 10mm of Z. And only really need to lift the cutter...so maybe instead of a screw mechanism it would be worth considering something servo activated. May need a few gears or some linkages to get enough travel out of a servo but could be a way to use parts people interested in cutting foam would already have on hand and eliminate the weight/cost of an additional stepper.

I like where you're going with the carriage as well, but wonder if maybe the cutter could be incorporated into the design more...could make it tricky to print so would still have to be multiple parts...but just thinking it would look slick to have a cutter/carriage that look integrated instead of tacked together.

I'm still trying to think of a good "printer style" Y mechanism so the machine could be build smaller. Was also thinking at that size it may be possible to get away with 1/2" EMT or some smaller square stock for the X instead of 3/4" emt just to help make things even more compact.

 

[moebeast]

Neat mobeast. Just a few thoughts....

For a dedicated foam cutter you only need about 10mm of Z. And only really need to lift the cutter...so maybe instead of a screw mechanism it would be worth considering something servo activated. May need a few gears or some linkages to get enough travel out of a servo but could be a way to use parts people interested in cutting foam would already have on hand and eliminate the weight/cost of an additional stepper.

I like where you're going with the carriage as well, but wonder if maybe the cutter could be incorporated into the design more...could make it tricky to print so would still have to be multiple parts...but just thinking it would look slick to have a cutter/carriage that look integrated instead of tacked together.

I'm still trying to think of a good "printer style" Y mechanism so the machine could be build smaller. Was also thinking at that size it may be possible to get away with 1/2" EMT or some smaller square stock for the X instead of 3/4" emt just to help make things even more compact.

I thought of the servo idea,and I like it, but I would need help with the firmware to change the z commands to a pwm signal. It is probably simple. I have seen them used on diy plotters.

As for integration of the cutter into the carriage, it should be trivial to add it on to one of the bearing pieces and still be printable. Combining it all in one will be more of a challenge, but I'll give it a try.

Going down to 1/2" tube wouldn't save much space unless we used smaller bearings as well. It is worth looking into.

 

[moebeast]

Here is the more compact version. It needs a esc mount and a way to attach the belts.

 

[jhitesma]

That's a neat looking setup, and still printable! But would still require the low rider style Z.

I've been thinking about this all day...and the more I think about it the more I like the idea of only moving the cutter and not the whole X axis for Z. It could really simplify things a lot and eliminate 2 steppers and leadscrews. Even if moving the cutter still used a screw it could be done with a cheap bit of all thread and a much smaller cheaper stepper since it's so light.

I was wandering the aisles of the big box hardware stores today trying to get inspired. Saw a couple of low cost towel bars that were almost perfect for an X axis...but not quite long enough

I just keep thinking that if the idea is only to cut foam then the machine can be built much lighter/cheaper since there's so much less weight on the Z and very little force while cutting.

Ryan (allted/mpcnc designer) is working on a new core-xy setup for a sand table that uses a lot fewer parts since it's designed to be light and simple instead of capable of machining. But the needle cutter is so low force I wonder if it could run on one of those. djk4linux already has the parts printed for one so maybe we'll find out soon There's no Z on that setup...but...something can always be rigged.

Dealing with a servo...could be done with a Gcode post-processor...or maybe a change in the CAM software...changing the firmware would be the hardest option but also possible.

Just finished printing the last wheel for my low-rider! Gotta to assemble them and see how the second half rolls. Wish I had some tubes now so I could fully assemble it and try pushing it around

 

[dkj4linux]

That's a neat looking setup, and still printable! But would still require the low rider style Z.

I've been thinking about this all day...and the more I think about it the more I like the idea of only moving the cutter and not the whole X axis for Z. It could really simplify things a lot and eliminate 2 steppers and leadscrews. Even if moving the cutter still used a screw it could be done with a cheap bit of all thread and a much smaller cheaper stepper since it's so light.

I was wandering the aisles of the big box hardware stores today trying to get inspired. Saw a couple of low cost towel bars that were almost perfect for an X axis...but not quite long enough

I just keep thinking that if the idea is only to cut foam then the machine can be built much lighter/cheaper since there's so much less weight on the Z and very little force while cutting.

Ryan (allted/mpcnc designer) is working on a new core-xy setup for a sand table that uses a lot fewer parts since it's designed to be light and simple instead of capable of machining. But the needle cutter is so low force I wonder if it could run on one of those. djk4linux already has the parts printed for one so maybe we'll find out soon There's no Z on that setup...but...something can always be rigged.

Dealing with a servo...could be done with a Gcode post-processor...or maybe a change in the CAM software...changing the firmware would be the hardest option but also possible.

Just finished printing the last wheel for my low-rider! Gotta to assemble them and see how the second half rolls. Wish I had some tubes now so I could fully assemble it and try pushing it around

I'm really interested in what you two are doing with this... and I really like the carriage design, Mark. But I'm also interested in a light-weight Z-axis like Jason describes. Here's what Ryan's ZenXY looks like right now



Like the Low-rider, there is a horizontal twin-rail gantry... but without any Z lift mechanism, as Jason mentioned. The rails could be spread apart to utilize a large enough carriage to carry a laser/needle-cutter/drag-knife/etc -- like Mark's idea -- but I really think it also needs a real Z-axis of some sort. The ZenXY is initially designed to hang underneath the work surface (it carries a strong magnet below a sandbox, dragging a steel ball bearing around in a layer of sand) and I'm interested in using it in the more conventional above the work surface configuration. The ZenXY gantry also simply rides on top of the outer rails, without any bearings below to "enclose" the rail, and depends on gravity to keep it in place.

I think Ryan has plans to eventually make the ZenXY design adaptable to other applications (laser, needle-cutter, plotter, etc) but right now the emphasis is on getting the sandbox art application finished. He's understandably a pretty busy guy and spread pretty thin for time... so I don't think he'll be modifying the ZenXY design for other applications anytime in the near future. -- David

 

[moebeast]

That's a neat looking setup, and still printable! But would still require the low rider style Z.

I've been thinking about this all day...and the more I think about it the more I like the idea of only moving the cutter and not the whole X axis for Z. It could really simplify things a lot and eliminate 2 steppers and leadscrews. Even if moving the cutter still used a screw it could be done with a cheap bit of all thread and a much smaller cheaper stepper since it's so light.

I was wandering the aisles of the big box hardware stores today trying to get inspired. Saw a couple of low cost towel bars that were almost perfect for an X axis...but not quite long enough

I just keep thinking that if the idea is only to cut foam then the machine can be built much lighter/cheaper since there's so much less weight on the Z and very little force while cutting.

Ryan (allted/mpcnc designer) is working on a new core-xy setup for a sand table that uses a lot fewer parts since it's designed to be light and simple instead of capable of machining. But the needle cutter is so low force I wonder if it could run on one of those. djk4linux already has the parts printed for one so maybe we'll find out soon There's no Z on that setup...but...something can always be rigged.

Dealing with a servo...could be done with a Gcode post-processor...or maybe a change in the CAM software...changing the firmware would be the hardest option but also possible.

Just finished printing the last wheel for my low-rider! Gotta to assemble them and see how the second half rolls. Wish I had some tubes now so I could fully assemble it and try pushing it around

I am trying to use the components from my Turnigy Fabricator to build this machine, so I only have four steppers. One of them has a shaft on both sides, so I could try and set up a single stepper for the X axis. I also want to keep the extruder intact to mount on my MPCNC, so I will shoot for three.

I think the Z on the carriage would be better, so the modelling I did today will count as learning. A high quality servo costs about the same as a cheap stepper, so I don't think I'll go that route. I think a printed rack and pinion might serve. The trick is to get the stepper and the cutter to fit in the same vertical area. I would like to be able to use a 32" door as a table.

I did learn to use "Joints" in Fusion360 tonight.

 

[dkj4linux]

I've decided that my MPCNC-imspired CoreXY machine -- that I've already built, tested, and demoed -- will make a better testbed for the horizontal two-rail gantry system than the ZenXY machine.



I've spent a couple of hours this morning in Onshape, designing a gantry-rail end to replace the 4 silver uprights and convert the current vertical (over-under) configuration to horizontal (side-by-side). I'm printing the first piece now to fit-check and once the rails are are in place I'll start looking at a carriage design similar to that Mark showed yesterday. A major consideration for the carriage in a corexy design is termination of the 4 belt ends... which I found quite tricky from before.

I'll probably document this conversion effort in the thread I've already got going (http://forum.flitetest.com/showthread.php?35285-MPCNC-inspired-CoreXY-laser-engraver) but I'll of course be keeping an eagle-eye on what you guys are up to over here. -- David

 

[jhitesma]

That over/under actually seems to make more sense to me than side by side for a foam cutter. It would give more usable work area for the same size machine I would think. That combined with a sheet feed system could give a very compact machine for foam cutting.

 

[dkj4linux]

That over/under actually seems to make more sense to me than side by side for a foam cutter. It would give more usable work area for the same size machine I would think. That combined with a sheet feed system could give a very compact machine for foam cutting.

It does make a lot of sense... and I did come to that conclusion when I rebuilt that wimpy little Makeblock system as a laser engraver...





Of course, the tall laser housing and no Z-axis requirement lent itself to the idea of a more upright gantry. And light as it is, that little machine has the same 2' x 2' footprint as the larger and much heavier CoreXY machine I'm converting.

I'm really just wanting to give the larger machine a lower profile and lighter gantry. The conduit and printed parts construction of MPCNC seems very heavy/clunky at this smaller size but of course it really shines at the larger sizes suitable for cutting full sheets of foam. But the CoreXY scheme -- I'm afraid -- doesn't really scale all that well. How much/little... who knows?

I guess I just need to play with it and see for myself... I'm curious. Besides, it keeps me off the streets...

 

[moebeast]

Here is where I got to today. I think this is going to work with simple X-plates. It needs a couple details before I print one, and I haven't re-designed the cutter attachment yet. It just needs four bearings to ride the rails, and an extension out the back of the bottom to hold a nut.
I should also add nuts and bolts to check for clearances.

 

[rockyboy]

I really like the look of this - but it seems the distance between the rails is smaller than the stock Lowrider design too, right? That'll mean a redesign of the all the other parts as well...