.1875 seems to fit perfectly. V-wheels are still perfectly seated without having to futz with and of the other hardware. I am using 3 pieces of 1/16" aluminum as a test. But my gap (again with the v-wheels perfectly seated) was 11/64" or .172" as measured with calipers.
It would be really nice if there was a single piece of extrusion that could replace the two pieces. I would buy it if Inventables offered it.
There would need to be a demand to justify the tooling.
I can’t see why there wouldn’t be a demand for this mod. I am having to deal with flexing with my 1000 mm x-carve when trying to mill aluminum. This may be just what I need! I would love to be able to use some 1/4 inch bits to hog out some larger projects and then switch to a smaller detail bit to make it pretty.
At present we are dealing with a pair of beams that are less than an inch wide and less than 2 inches tall and are mostly air. Maker slide I believe was designed for use on 3D printers that have beam spans of less than 2 feet in most cases. Also 3D printers do not have any side loading or 3 to 5 pounds of weight in the middle of the span.
I understand why Inventables used maker slide in order to keep cost of the X-Carve at a price point that people can afford.
What Inventables did not foresee is folks pushing there machines to the max and the problems they are having with flex and beam sag.
I’m one of those people that will be pushing my machine hard. I will also be making parts that need to hold close tolerance, so I need to increase the rigidity of my machine.
One of the problems is that the gap between the 2 maker slides is not a even number that you can get metal in. The CAD drawings show the gap to be 4.15 mm This translates to .1633" . @StevenSchmelling suggestion .1875" plate is only .0094" less than 5 mm and would be easy to get here in the US.
FYI - I purchased 3/16" x 1" steel at the local hardware store, sandwiched it between the two maker slides and used 50mm “furniture hardware” bolts and nuts (flat heads). Works perfectly. The only downside is that I obstructed the passage through which the 2nd y axis stepper wire passes. That wire now runs around the back side of my machine to connect to the other y axis stepper.
I also used 1/4" aluminum plate to recreate the z-axis spindle carriage. I extended its height by 1" and added a third set of v-wheels. This allowed me to place the two universal spindle mount brackets farther apart. These two mods have virtually eliminated flex on Z and X. I can now run 1/4" flat end mill at .2" x 40"/min with no chatter and perfectly smooth cuts. I milled a circular pocket in poplar and the bottom was like glass. This would have been disastrous before the mods. I am using a 600watt spindle driven at only 48volts which yeilds only 6600 rpms (it is a 110 vdc spindle but my new power supply has not yet arrived from China).
Today, I am adding a single mid-beam support to each y-axis slide and I believe I will be good to go. I will try to post pictures if anyone is interested.
It seems to be working nicely. Here are pics of the mods: 3/16" steel sandwiched, y-axis supports, thicker, longer spindle mount with three wheels.
Spindle Mount: http://garritanoreunion.com/rexel/rigidity/IMAG0681.jpg
Y-Axis Support: http://garritanoreunion.com/rexel/rigidity/IMAG0684.jpg
could you reupload the files again. My computer does not recognize it on the pdf. It knows and reads the pdf, but there are no images
Do a right click and save as. Then try opening with adobe and see if that works. I just checked both files and had no troubles with them.
Good looking mods. will keep things much more ridged.
ok, that worked, Thanks!
THanks. Just ran it for three hours hogging out my wasteboard. Smooth as glass.
Hogging my wasteboard ? Do you mean facing with a wide end mill to give it a uniform flatness.
Yep. It was great to finally see all of the low and high spots. Nothing crazy but, at least now I know it is perfectly flat.
How did you go about drilling the wholes through the rails? I imagine they need to be perfectly placed and perfectly straight. What was your method of choice? Clamped together and on a drill press?
I’m not sure how Earwigger went about drilling his maker slides and the spacer piece. I do know how I will go about it when the time comes.
I may have an advantage over most of the folks that have bought machines and are thinking of making mods to the X rails.
I have a CNC milling machine that I will set up to drill the holes I need in my spacer plate. There will be 6 sets of holes spaced along the plate. Each set has 2 6mm reamed holes at 20mm center distance for 6mm locating dowel pins and a 5mm hole centered between the 6mm holes. Because my mill can not drill all the holes in one setup I will build a fixture that makes it possible to do the drilling in several setups.
The Maker slide will go into the same fixture and the 6 5mm holes for the bolts that clamp every thing to go through.
The plate I plan to put between the maker slides will be 92mm tall or 3.622" The space the maker slides through is 96.5 tall so I have some clearance.
I didn’t want to chance having things not lining up by machining things separately. I squared my machine, dialed it in really well and while it was still attached, I slid the steel between the slides. It was a snug fit. Then I retested the gantry - it worked great. I put a steel plate on the top and bottom of the assembly to maintain alignment and clamped the bejeesus out of it. Slid the gantry off and took the whole thing to the drill press. Drilled all the way through all three pieces. Then widened just the top hole to accommodate the larger diameter furniture faster nut, then inserted a screw, drilled the next hole, etc. Mounted the whole assemby with loosely fitted nuts on the through bolts. Replaced the gantry, and began tightening the nuts a little at a time, continuing to test gantry movement. I have to admit, it worked pretty well and it was SUPER lucky that 3/16" happened to be a perfect fit. The furniture bolts, I believe were either 50 or 40 mm and did not need to be trimmed down – another lucky break. Plus the bolts came in black - also lucky… it was a charmed project. Once everything was tight, not a single adjustment was required. “I love it when no plan comes together.”
Also - keep in mind the channel for your 2nd stepper on that axis. My bolts made it impossible to refeed that wire through. It now runs around behind the machine to connect. At least I can’t see it.
With my machine headed my direction it is time to do more design work on the mods I plan on.
Here is an updated PDF of what Inventables referes to the X axis and on my machine will be changed to the Y axis because on my machine it will be the short axis and X will be the long 1800mm axis.
I have added the new Z axis that handles the taller end plates that make clearance under the carrage 117mm.
I don’t have the stepper or the spindle yet.
I have reversed the Z axis in that what would of been the maker slide moves up and down and what would of been the V wheels are fixed to the carrage.
My Z axis will also use a 10mm ball screw in place of the acme or 8mm lead screw that can be ordered with the standard machine.
x-carve_gantry.asm.1.7.pdf (3.2 MB)
What type of linear bearing are you going to use for “what would have been the maker slide?” I assume you mean the piece with the triangle pockets moves up and down along with your z-axis motor and the acme nut is fixed in place?
and was thinking about using it, but it comes with a Nema 17 motor and it would take some doing to retrofit.