Hogging my wasteboard ? Do you mean facing with a wide end mill to give it a uniform flatness.
Dave
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?
Iâm 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.
Dave
I didnât 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 â 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. âI love it when no plan comes together.â
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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 canât 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 donât 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.
Dave
x-carve_gantry.asm.1.7.pdf (3.2 MB)
What type of linear bearing are you going to use for âwhat would have been the maker slide?â 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?
I have one of these in the shop: http://www.amazon.com/sliding-working-stroke-engraving-machine/dp/B00K0IQ5R4/ref=sr_1_12?ie=UTF8&qid=1435499555&sr=8-12&keywords=cnc+z-axis
and was thinking about using it, but it comes with a Nema 17 motor and it would take some doing to retrofit.
That is a interesting unit. One thing Iâm not real fond of is the sheet metal box it sits in. It may be OK with the load sitting on the traveling block, but would it flex if in the vertical mode.
I am going to post photos of the linear slides I will be using on my Z axis on my build log in the assembly category.
Dave
It wouldnât flex if the entire back was attached to a 1/4 plate, like on my latest mod. But that Nema 17 looks like a toy. I understand it has tremendous mechanical advantage with that screw, but still ⌠look at that tiny thing.
I also installed a 3/16" thick piece of steel between the maker slides to stiffen things up.
I purchased a piece at Loweâs. 3/16 X 3 X 48. Cut it to 39 1/4 inches long and it wouldnât fit inside the x carriage because of the bolts for the wheels. I took the steel to a machine shop with a big shear and they cut it to 2 1/2 inches tall. Fits perfect now. Bolted the rails and the steel together as described with the furniture bolts.
To say that the cable for the second y stepper wonât go through the hole anymore is correct, however, you donât need to run it behind the machine. In the top of the rails there is a slot that the cable will push down in to. It is the same slot that the belt occupies on the back rail. I also took some clipped off zip tie ends and pushed them into the track along side the cable for the stepper motor to snug up the fit and keep them from popping out. Worked like a charm.
This modification made a very significant change in the rigidity of the carriage. Well worth the time and $$ to do it. Oh, I also made some very sturdy L brackets out of some angle iron and attached them to the Y rails to help eliminate any side to side flexing issues. .
My machine cuts much better now and I have eliminated much of the chatter that goes along with milling aluminum and deeper cuts in wood especially cross grain cuts.
Before the mod, I tried to mill some 1/2 6061 aluminum. The cutter just wondered all over the place and made a real mess. I am surprised that the bit didnât break. With the mods, I get a smooth and clean cut milling aluminum 1/2 inch thick all the way through.
By the way, get the 40mm bolts. I got the 50mm bolts and had to cut off about 1/2 inch because they were too long.
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@CharleyThomas Do you have some detailed pictures? I have a 0.8kW spindle on the way and would like to do this modification at some point too.
Here is a shot of my x axis. You can kind of see the plate between the slides and then the furniture bolts. At my true value, they happened to have the 3/16" plate x 1.5" so I only had to trim up the end.
I have some 3/16" plate laying around from a previous project that never went anywhere. when I tried to place it between the two pieces of makerslide, it seems too thick for the gap. Did you have any issues with it fitting? Did it create any issues lining up with the v-wheels because it was too far apart?
Mine slipped right in snugly. Try loosening one rail, fitting a piece in, snugging it up and see how far off your v-wheel is, if at all. My wheels seem perfectly seated (as perfect as those wheels and rail get anyway). Keep in mind, you can add a washer to one set of wheels or grind down a larger spacer.
Good luck.
Iâm happy to see that folks are able to do this mod to there machines and that the mod is making a difference.
I am just days away from having the engines installed in the W T Preston so Mike and I can do testing on the temp pond I set up in my driveway.
Dave
Yeah, I figured I could grind down the larger ones if need be. Hopefully it wonât be necessary. For now Iâm just finishing up the build as per the instructions with whatâs in the kit, but a bigger router is on my radar. Thanks for the input.
X Carve Rigid Mod.pdf (132.1 KB)
Here is a detailed description of how I installed the steel spline. I will repost with photoâs of the final result later today. I believe it was DavidSohlstrom that posted the size for the spline.
Hope this helps anyone who is apprehensive about making this worthy upgrade. It really does have a significant impact on the machine⌠in a very positive way that is.
Charley
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Very good write up on how you applied the mod to your machine. This will help those thinking about doing the mod. Looking forward to seeing the pics of your mods.
Dave
As promised, here is a pictorial. Unfortunately, I did not take these while I was making the modifications but hopefully with the write up and the pictures together it will help others. At the end of the document are some other things I incorporated such as a cabinet with a air filter and blowers for the electronics and a touch plate for Zeroing the Z axis.X Carve Rigid Mod With Pictures.pdf (841.3 KB)
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