Has anyone replaced their Z axis assembly for greater travel?

As per the question, I am reviewing a potential replacement of the Z axis assembly in order to have greater Z travel. Your comments and especially your experience in this upgrade would be appreciated.

I’ve not yet received my 1F, but am looking at a solution to increase the Z height.

My first thought was to mount the Y rail castings onto rails made from CLS timber, like this. However, this would perpetuate the design “issue” limiting the width of the stock that could be secured onto the waste board.

So I thought about using aluminium or steel blocks, sized to match the Y rail castings and secured stainless steel bolts, through holes in the blocks, into the baseboard. The blocks would only need to be about 100mm x 60mm in size, and perhaps 50mm deep, raising the Z height by 2 inches.

Of course, with some machining expertise, you could machine a recess into the top of the blocks for the Y rail castings to fit into, and the bottom of the block so you could “stack” them for an even greater Z height.

But these are only thoughts, at the moment!

Someone made Rider blocks but that increases clearance not travel. I have not seen any posts relative to a custom axis

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:thinking: might different length end mills and a tool change mid carve work? Admittedly a bit clunky

Won’t the overall stability of the machine become an issue if you raise everything up a few inches with riser blocks?

As the spindle/router is zipping back and forth there is a lot of lateral force applied to the mounts. If you double the height, you decrease the stability of the mounting system. The material used to create the risers is not the issue. It is the longer moment arm created from the attachment point at the base to the point where the force is applied at the X rail height. Using only two riser blocks under the ends of the X rail would probably be a more stable configuration than four riser blocks under the Y rails.

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I only know of one former 1F owner who heavily modified his Woodworker to, among other things, accept a Z axis assembly from RoverCNC. He milled a custom aluminum adapter plate to get it to attach to the 1F X axis block. He used it for a spindle with a Mechatron ATC adapter.

Hey Tom, hey Gary @GaryD,

This was discussed here: Universal Z Axis Assembly.

We also had this the other day in this thread. Mentioned was:

Hey Bob, hey Peter @Nightowl,

you are right, Riser blocks seem something easy to add but most people underestimate the increasing leverage force. Nonetheless they are offered.

But the the increased leverage force acts on the two X rails then via the Z gantry. I would avoid that too.

I plan a table where the room where usually the wasteboard takes place remains empty, with the possibility to mount different wasteboards “floating” when necessary and more room for larger workpieces or a large 4th Rotary Axis.

But when thinking of such things one must be aware how strong and stiff such a U-shaped base has to be. You will either have to use thick dampened beech timber to construct such a thing and use triangular reinforcements or, as I plan it, weld it from steel profiles.

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Hey guys,
I will throw in my input in real quick. I can only attest to what I have tried with success. If you are aware I do offer some riser blocks that raise the x axis up enough to carve into a 8" thick piece of wood.
I do pocket tool passes from time to time and I have not had an issue. However I mainly use the riser blocks to do a vcarve into a thick piece of material.

Nonetheless I am not great at physics and have a question. Referring to the leveraging force… would this force be toward the 8 bolts holding down the x axis? I replace these with 90mm bolts when using the riser blocks.

Thanks guys

Here is my listing for the riser blocks: Riser Blocks | Etsy

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I think the bolts would experience the normal tension and shear forces associated with a fastener holding two components together - your longer bolts can’t hurt. I think the bigger issue is the lateral force which translates down from the top of the x axis (which includes the mass and force coming from the z axis assembly, spindle, etc) through to the bottom of the y axis.

My hope would be if I went with any type of riser block, or assembly to gain more travel (the OP’s original question), I would be choosing feeds, speeds, tooling, paths,… that keep unwanted forces to a minimum. I imagine it also will depend on what you are producing, and to what tolerances you want or realistically need to be working.

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I would think 4 riser blocks would be better than two at absorbing and preventing the forces

I can’t imagine any force strong enough from raising the Onefinity on blocks to affect the cutting operation. If the blocks are sturdy the machine will be too. If there is no give in the blocks there will be no more give in the machine than being directly on the table. Besides, any give will break the bit before the machine flexes.

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Hey Alden,

oh, more traffic in the Forum now. After midnight in Europe, now’s the time when the americans have quitting time, and me have to go to bed soon :slight_smile:

From physics point of view, that is not true. The longer the lever, the stronger the force occurring at the target point, with the same triggering force. And in most cases not the Riser Blocks will be the weak point, but the tabletop they’re attached to. If it’s a MDF surface, only compression of material will be enough for increasing give and instability.

You have to imagine that a power tool like a Horse Power Milling Motor not only is powerful when it does its main action, i.e. lifting a chip from the material by the bit’s flutes, but also that plunge and feed rates selection produce enormous force applied. With a CNC you can select milling motor speeds and feed and plunge rates that nobody would be able to keep with a hand-held router.

That’s for sure! :slight_smile: I mean, before something else would get broken!

I’m not thinking of enough movement to break a bit, but enough to affect the quality of the cut.

Yes, through bolting with a backing plate or a large washer will improve the stability of the connection to the table. That’s where the effect of the increased moment arm will be felt.

Rather than raise the machine, lower the wasteboard. Have a bed that can be raised or lowered like some 3D printers have. Don’t build a U-shaped table, build a square with all four sides and have an opening in the middle the size of the active area of the machine.

I’m thinking that is what I will do to create the space up front to be able to work pieces vertically. I may or may not cover this. I think I only need about 5 or 6 inches. Don’t see the need to work on anything thicker than 4 inches. I would still have a 48"Wx26"D horizontal work surface so could handle a 24"x48" piece of plywood.

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Hey Bob,

That would be more stable, but I need to build a U-shaped base in order to run larger workpieces trough it

How ‘large’ can they be? You’ll be limited in height by the distance from the floor to the table top, so about 36 inches more or less. That should be something that could be lifted over a rail in the front.

It is certainly possible to build a rigid U-shape table. I have not totally given up on that idea and will probably flip-flop a dozen more times before the 1F hits my doorstep. :slight_smile:

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Hey Bob,

Yes, I found it very advantageous too that Onefinity has so much backorder time, monthes in fact, to make room for the packages, room for the machine, ideas for the table build… But shit, now we got this tracking E-Mail now!

Long, not large. Sorry.

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Long as in wide (X dimension), or long as in vertical height (Z)?

I don’t know if the months of waiting is a blessing or a curse. :slight_smile:

I would like to start building a table but at the same time I would like to have the machine here to know firsthand dimensions and to evaluate the possibilities. I have no pressing projects to complete with the CNC so I will wait. I bought the Kreg 44x64 inch bench frame and put it together but that is as far as I have gone. I will hold off on building a top for now.

I’m thinking from what I have read on here (because that is all I have to go on at this point) that I want to look into reversing the Y rails and bring the servos up front. I think this will let me shift the cutting area back a few inches and position it behind the front rail of the Kreg frame. If that works; and I won’t know for sure until I have the Journeyman here and assembled; then I plan to create a vertical clamping surface about 6 inches behind that front rail of the frame.

I’ve been thinking about ways to remove that top frame rail or shift it back behind the vertical clamping surface, but nothing has come to mind that I am positive will work and maintain the rigidity of the frame. I do have one idea but I need the CNC to be sure of where to move the front upper rail to.

Hmm, I was thinking more about allowing additional space below the lowest Z height so I could carve thicker material with longer cutters, but I get the additional stresses and strains on the machinery and affect the rigidity.

I suppose it would be a lot more rigid to mount the machine on to a welded steel or bolted aluminium extrusion frame, and incorporate a removable/adjustable waste board, but that would need to be bolted down to ensure that remained rigid to the frame. A bit like your frame/table combination, @Aiph5u, but I don’t have shares in an aluminium extrusion company :rofl:!

It’s a curse, for sure!

Will that be big enough, in depth? I’m happy to be proven otherwise, but I thought (without checking) the minimum recommended table dimensions are 4’ by 5’?

Decisions, decisions… :thinking: :thinking:

Yes, it’s only the frame, I have not built the top yet which will be larger. At least 50x75 from what i believe others have done. But I am waiting until I have the Journeyman here and can take measurements directly. I want the table to be big enough to support an enclosure. I need that for two reasons.

Here is one of them.

His name is Ziggy, and like most cats he gets into everything. And in this corner of the basement where I will setup the CNC was one of his favorite things. Since I moved that out I suspect when the CNC gets zipping around to him it won’t be much different than those HO cars and he’ll be jumping up there wanting to play. Which would end in a bad way, mostly for him.

So I can’t have that.

The other reason is the laser. I want the enclosure to protect eyeballs, mostly Ziggy’s because he won’t know not to look at the light and he has told us he does not like to wear sunglasses. We tried; he wanted no part of them. :slight_smile:

It’s not possible to isolate this part of the basement from the rest of the house. And closed doors are against his rules. If there is a door closed somewhere he will sit that and scratch at that door until he digs a hole in it or you open it for him. I think he does it just to mess with me. :slight_smile:

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