I’m thinking about adding the stiffy rail to my X50 Journeyman. I’ve been using a 1/2" upcut bit at around 300 ipm with a 3/8" cut. I get a bit of vibration when doing so but the cut looks fine. Usually this is just my roughing out cut and I’ll leave .020" for the final pass with a 1/4" bit.
I have the Z-20 upgrade and I’m using a 3hp spindle. For those of you who have added the upgrade did you see a difference? I’m in the middle of doing some upgrades to the Z axis (replaced the stepper with one with a brake) so I have one spare stepper. So I’m going to do the Y axis pro upgrade. I’m thinking with even more power I could push my Journeyman harder so the stiffy might be a worthwhile upgrade for me.
I have a Woodworker X50, and recently added the 3rd rail.
In anticipation of the switch, and to see the difference if any, I measured deflection at 3 locations on my machine, applying push/pull force (max 50N) in both X and Y direction. I did the same after the installation of the 3rd rail. Deflections were measured using a 0.002mm increment dial test indicator, and video recorded for more accurate reading.
Using software I created scatter plot graphs for deflection (microns) and applied force (N in 5 N increments).
Results showed the 3rd rail reduced machine deflection in all locations and directions by about 25 - 45%.
The graph below shows the deflection at the bottom of the Z20 assembly when force is applied in the Y- direction, with and without the 3rd rail. NOTE: all axes were positioned in the middle of their max travel, with motors on.
What are you cutting at 300 IPM, I use a 1/2" UP and run about 100 IPM and feel like I am pushing it, I cut all hardwoods, walnut, maple and cherry most of the time.
Also what RPM?
Pat
TM, were you noticing any issues while cutting before adding it? It’s possible the vibration is very small since I don’t see anything in the cut.
Pat, 300 ip is the standard recommendation for the bit. I run it at 15,000 to 18,000 rpm.
I’ll most likely just order it as being even more rigid isn’t a bad thing. I was hoping to start testing my brake engaging circuit this week. Now is the ideal time to install it. It has a 1 to 2 week lead time plus shipping time and with the holidays it could be early next year before I see it.
I knew the machine allowed for a fair amount of flex before adding the 3rd rail, but because I am very conservative with my machining - preferring accuracy/finish over speed - I am able to mitigate the effects of deflection as best I can. Adding the 3rd rail was partly an experiment to quantify the difference, but also as part of my plan for a new Z assembly I am designing. It will use linear rails, and I plan to leverage the benefits of the 3rd rail by having the new Z assembly mounting plate also attach to the top of the 3rd rail block, not just the X axis gantry block.
There is not a lot of data like this out there to find, but I imagine the results I found are on par with similar hobby CNC routers - in general not a very rigid class of CNC. Having said that, my next build - and hopefully sooner my new Z assembly - will use linear rails and guides (more similar to the new Shapeoko’s HDM), so I am curious if that will make for a more rigid machine.
For now, I can use the deflection data along with some software to keep the ‘theoretical’ deflection as a fraction of my toolpath chip load, with the result being reduced or eliminated chatter while machining. So far the numbers, and my results when machining aluminum, seem to support this.
Almost all hardwoods (maple, birch, cherry, oak, etc). Wood, like cherry, will burn if you go too slow. So I try to keep the speed up when hogging out material. If I remember correctly I run a 1/4" up cut around 100 ipm. But I’m usually doing a finish pass.
I will be machining a whole new backplate, which will be at least as tall as the X50 + 3rd rail blocks. Rails attach to that, guides to the moving plate. I purchased two Carbide 3D Shapeoko HDZ 80 mm mounts that will attach the spindle to the moving plate. My ATC spindle is heavy and very tall, so having the two mounts will add rigidity.
Hey there TMToronto, before you get to far along on the new Z axis can we chat? I too am beginning to see the Z gantry as a weak link, but not for your reasons. I am looking at Z travel. Using an ISO 30 taper with an ATC starts to eat up height. Yes I am still putting the new machine together… got COVID (over it now) so that set me back again.
The X & Z axis plus a 25# spindle gets heavy for one guy. So tomorrow a “single leg wire rope sling” arrives… soI have a date with my come-along to lift that sucker. Still haven’t figured out if I need to elevate the Y axis with spacer blocks. Like I said, tool clearances.
Oh by the way anyone reading this, we blew by the OneFinity warranty a long time ago.
Happy to chat - you know I enjoy the engineering and build aspect of the hobby as well as the machining. I added 8020 extrusion blocks under my Y axis blocks when I started the ATC phase of my build - the limitation at that time was how low the X axis gantry block was, relative to the pull studs of my ISO20 holders. I did not want a ‘from below the table’ tool rack option at that time, as I had invested a fair bit into my cast aluminum table top.
My goal for a new Z assembly will also be to get more travel in both directions, but especially to get more downward travel. I have the Z20 on its lowest position, and have ~20 cm between it and the cast table. It is ~2 cm lower than the X axis gantry block. I plant to have the back plate of my new assembly level with that block, so right away that gives me and extra 2 cm clearance. It does not seem like a lot, but I am guessing you appreciate how these little differences can have profound impacts on the rest of how the machine setup works, especially the ATC aspect.
Reach out any time - happy to gain your insights as I believe your engineering experience may provide greater value than the results of my current investigations.
Damn Canadians and their metric … hmm 20/2.54= 7.87" … chuckle. I used to play French Horn and we often had to transpose sheet music on the fly. Boy is that a lost art. Sorry just hit my funny tonight.
I will let you know how my initial rigging turns out. Should have it by Monday.
Well, if it makes you feel better, I have often the need to do conversions back to metric when going to many manufacturer feed/speed docs, or videos from non SI machinists/countries
Looking forward to your progress. Also, when your time permits, please share your thoughts on the Z assembly functionality, rigidity, and design options - would enjoy the discussion.
I grew up outside of Erie Pa. right on the Pa/NY state border. Buffalo was oh about 80 miles (130 km) away. So, before the world got crazy the phrase was… “Do you want to go see the cousins?” which translated to “Do you want to see the falls from the Canadian side.”
