Thanks, I am sure it’s a good product. I was curious to see whether it improves on a shop-made solution.
You’ve addressed my curiosity.
Hey Roger,
Do you still have the 65 mm mount installed?
The router or 65 mm spindle that is slid that much downwards into the original 65 mm mount is already a source of adding more leverage force to the system. If you look at professional milling motors, they are always clamped near the bottom where the axle exits the housing. Now instead of adding a second instance of increasing leverage force into the mechanical system as Riser Blocks do, I would rather lift the router / spindle so that it is clamped more at axle end. As you correctly stated, the Z stepper motor is in the way and router / 65 mm spindle would bump the stepper cage. But this problem can be solved by lifting the Z stepper cage using taller stepper mounting blocks (see pic 2) and extending stepper axle with another coupler. The advantage over Riser Blocks between X and Y axes is that 1. you do not add a source of increasing leverage force somewhere in the mechanical system, and 2. you eliminate a source of high leverage force that is present in the original system. The difference is, when you lift the stepper cage, you do not interfere in the stability of the mechanical system between your milling, plunging and feeding bit and the machine base.
Yeah it’s working fine with the riser blocks. No issues with what I use it for
Hello all.
Does anyone have a profile for making temporary riser blocks out of wood handy?
I am interested in buying the 3D printed ones, but unfortunately, I have a project that cannot wait for delivery.
Before I take my 1F apart, it would be very handy to mill out the blocks first!
Thanks!
Hey Andros
I can ship them tomorrow if you make an order today. And we can change up shipping to make it faster if you are in the United States
Thanks, I messaged you.
Hey Tom,
a little like shown here, except that there the user uses an extruded aluminium profile (instead of two 3D-printed plastic blocks), which I think is much better.
Curious… why not glue some scrap plywood together and use that. Would only need a couple of 3/4" pieces per foot…
would probably save a lot of time, and i wouldn’t trust the print to not collapse under weight and movement (not saying it wouldn’t work, because it might, but unless it’s solid (no gaps) the possibly exists). Depending on how you are screw it down i would also be concerned it would shake off with the higher CG (a tnut and a machine screw would eliminate my fear here)
Just things to consider if you haven’t
Hey Chris,
probably the same reason why the Onefinity CNC machine’s feet are made of aluminium and not of plywood 
I’m a utilitarian, so i was just inquiring
Hey Chris,
wood consists of cells that contain liquids (replaced by air when dryed), and this makes the material too compressible for this application. The leverage forces would make the mechanical system too susceptible to bending.
I can’t find what the janka rating of plywood is, but it’s alot… alot more than the cnc is and whatever is added ontop of it. That’s why they use it as a base for your roof and maybe your floor, not to mention for cabinets which can hold large pieces of stone (granite).
If there is going to be any variation of collapse it’ll be in the 1,000ths of an inch
Hey Chris,
from mechanical point of view, there is a big difference between if you put the entire Onefinity on a more than 48" x 48" big table top made of plywood or if you put one single X foot on a plywood piece of 4" x 2.3".
A road may support your car, but a small cube of road surfacing material placed under one wheel possibly not.
Yes, that’s why i was asking why not… because if you added a small piece per leg it’ll raise it up, without raising the work surface. I found the plywood for my risers in my scrap pile, oversized them for the feet, and screwed them in, then got longer lag bolts and secured the cnc to the subframe.
That’s actually what i did on top of my 5×5 1/2" baltic birch, ontop the torsion box because even with the stock risers it only barely cleared the surface, like maybe 1/8".
As for your car… there’s a very small piece of it that actually makes contact with the road, basically the size of an index card depending on the size of your tires and inflation level.
Will the road hold it depends on who built it and how good they built it with what kind of materials they used to build it.
Hey Chris,
but the problem here with the riser block is not in the compressibility of the material. The play with which the machine will be bent will be in the linear bearing’s play. What you add by adding a riser block under the X axis, is leverage force, and deflection amount. The CNC machine is a mechanical chain, and force applied to one end will bend the entire system until the other end. One end is the cutting edge of the cutting tool that tries to cut the workpiece, the other end is the workpiece attached to the machine bed with the four machine’s feet attached to this bed. When you drive the cutting edge (one end) through the workpiece (other end), all parts between those ends (milling bit’s cutting edge → milling bit’s shaft → spindle collet → spindle axle with spindle bearings → spindle holder → Z slider bearings → Z assembly → X carriage → X linear bearings → X assembly → X feet → Y carriage → Y linear bearings → Y assembly → Y feet → table top → workpiece clamps → workpiece) will be subject to forces which originate from the cutting edge of the bit meeting a resistant force on the workpiece. The question is now to design this mechanical chain to avoid weak spots. Between different chain links, there act leverage forces, which have always one effect: To make a resulting force bigger or smaller in relation to the acting force.
Usually you want that your milling motor not to be bent away from the ideal cutting position by the mechanical load of the cutting process, so your goal is to have a machine whose mechanical chain is stiff and is not bent.
Therefore any engineer will tell you
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if you want to make a machine like the Onefinity higher in relation to the machine bed, you would rather put a riser under each Y axis than under the feet of X axis, and
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you would avoid using small riser blocks, but use wider parts instead.
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if you nevertheless want to put the Onefinity’s feet on a block that is only as small as the foot’s footprint, better choose the strongest material.
But the play that you introduce with the risers as described in the thread earlier will not consist of the compression of the riser itself. The play will be always be in the linear bearings, and increasing the length of the lever (that consists of the entire X assembly height) will make the effect of any bending bigger (and the danger of chatter) and of course increase the linear bearing’s wear.
So if you’d ask me, how would I make a Onefinity one or two inches higher than the machine bed (=here a table top)? I would anser: I would not put risers under the X feet, but under the two Y rails, with a part that goes all the way through from front foot to rear foot, one on each side, and I would make it of a 4" wide, possibly 1-2" high, steel extrusion profile with 1.5 or 2 mm wall thickness.
oversized, that’s what I meant with 2.) above
Did you do that on Y feet?
Yes, but still it is a big difference if this small tire’s surface is on a little cube of road material, or on a larger road surface.
I agree, that’s why i was speaking of the higher center of gravity.
And yes i did put it on the y feet.
Putting pieces of plywood on the y would have resulted in the same thing as raising the x except i also have clearance where the x blocks are because it’s like 1/8" on the foreman, but without compromising the CG at the x
Hey Chris,
I realize I can see that in your image from the other post now.
My plan is not to use a table top at all, but to weld a U-shaped base from steel profiles that holds each Y axis at its sides and has a space in between for things like rotary axis or higher workpieces, and a system of height-adjustable wasteboard/machine beds.
That was not understable to me. What?