evildean published a new build:

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Yes, I imagined I would need to build a cube with V-slot extrusion. The extra V-slot, plates, t-nuts, and bolts needed adds to the cost considerably! Initially the presumed benefit was an increase in cutting capacity, but the top of the Z-axis would contact the 40x40 cross member instead of the router bit. Might save me a router bit, but does not increase machine capacity!
Current configuration allows for 28 inches cutting on the Y-axis, and 32 inches on the X-axis. X-axis potentially has an infinite capacity because you could continually feed material through sides. I could get another 2 inches easy if I put spoiler board on top of the 40x40 cross member, but I would need two 3 inch lengths of C-beam in place of the V-slot spacers I created to mate the Y-axis with the X-axis. The C-beam spacers would increase the Z-axis travel and are another modification I am considering regardless.
Presently there is no perceptible deflection anywhere except on the Z-axis. Not enough to make the machine unsuitable for production... but present none the less! Side to side the Z-axis is solid, but if I grab the Nema motor on top I can realize some deflection front to back. This is probably the weakest point of the Openbuilds offerings, and I imagine any other entry level machine. Anyone address deflection on the Z-axis? I am open to thoughts, suggestions, ideas in that regard for sure.

 

Thank you for taking time and sharing some experience with the new guy fellas! Always appreciated. I'm feeling your vibe Flo... I would much prefer a machine with zero deflection. Coincidentally I believe I may be taking your suggestion ala OX around the C-Beam Larry? I will post pix of my progress shortly. From what I have gathered, I maybe in the minority utilizing the OX model "cage" around the C-Beam, while retaining the gantry plate and mini v-wheels provided in the C-Beam bundles? (Not to be confused with the C-Beam Machine Kit!) I wonder if my description makes sense to many? I've got to get these pictures up. A thousand words and all that...

 

All right, here is what I have right now. Preliminary result suggests I have not improved the aforementioned deflection on the Z-axis much? Maybe I need to preload the V-Wheels a touch more? Still I remain optimistic. It will be addressed!

 

Larry mentioned linear rail earlier. It seems most logical to me.... What is the consensus on the inclusion of OpenRail?

 

Side note:
The Makita trim router pictured is just setting in the too large mount I ordered from OpenBuilds. Anyone have a source for a couple of the spacers used for a 65mm router body with this mount? Shipping to zip code 53590 if possible. I qualify my next statement by mentioning I have better than 25 yrs. experience as a carpenter! That Makita trim router is so quiet just running in my hand.... that I think it may be broken? I will duct tape it to the Z if thats what it takes to cut something soon! Then there will be more questions.

 

Oh Yea, I forgot to include a picture of the workbench I assembled. Quick and dirty but I am very satisfied! Kreg jigged together for the most part,and I had all the tools and hardware already so $125 for materials at "Home Depot", and an afternoon later provided a crucial piece of the puzzle.

 

I agree with all of you. My mechanical senses tingle for all the reasons mentioned. My intent was to cut custom gantry plates, hopefully with this very machine, that will allow me to stand up the Y-axis beams and realize my intended vision for the machine originally. With an offset gantry I might gain up to 5 inches on the Y-axis? If the Y-axis beams are on edge instead of flat I also gain about 3 inches on the X-axis. I arrived at this point where I had to place my initial order from Openbuilds, because I needed something tangible in order to gain perspective, and explore these very limitations. In my efforts I am pleasantly surprised by the rigidity of the Y-axis C-Beams in this configuration! I would not have automatically considered this config. The exposed screws in this position make me nervous for obvious reason, but the strength where the X and Y connect is solid. I really need more time to analyze the situation, and better determine what piece or section is the root of my Z-axis deflection pushing front to back. Everything else in this temporary configuration feels rock solid!

@Rick 2.0 Thank you for the link to Chris Laidlaw's stuff. I knew he was a source of gantry plates and such, but did not know about the eBay store with a convenient stock of very nice looking items. No way will I see results like that with my build... Wow!
chrisclub1 on eBay

 

@Rick 2.0
Yes, that is the spindle mount adapter I was looking for. I just don't have any friends cool enough to own 3D printers. Truth be told, I probably do.... I should get out more! Thank you for the heads up.

@Steven Bloom
Thank you for pointing out the spindle plate. I had previously read your Sea-Ox blog with great interest, and had bookmarked your generous source of custom plates. Your design focus, maximizing the Z-axis travel, is of particular interest. I will look forward to your updates.

 

I continue assessing the deflection I see on my Z-axis, and I want to say the Openbuilds gantry plates I've used are the source for much of it?



I think I may improve some if I flip the X-axis beam over so the screw faces forward. That way my Z-axis would bolt through to the C-beam gantry plate with the added benefit of its four mini v-wheels. Does that make sense?



Also I think I really want one of these... CNC Router Mount and Dust Collector Kit

 

@Florian Bauereisen
Thank you for the encouragement. It will require some assembly tweaks to put all on the one side. Im still trying to find time for it though. I will post an update soon.

 

@stargeezer
I have come to the same conclusion. Honestly I'm not sure the Openbuilds plates are worth using for anything! As you noted too many holes and far to thin. I will be purchasing better build plates for sure! Sucks because I have realized my estimate of $1400 usd. Any additional dollars spent are over budget. Maybe I should have considered the "V-Carve" kit from "Inventables" after all...?

 

@stargeezer
My previous post does sound a bit harsh. Your perspective and description of the openbuilds plates is magnificent. I absolutely agree! After some careful thought and reconfiguration I have eliminated much of the deflection despite the limitations. Now its mostly the C-axis beam twisting, but it is still much stiffer. I will post some pics again shortly. I have also contacted Chris Laidlaw for some of his offerings. The stuff in his store looks amazing! Made in the USA!!! Affirmation is the best fuel for motivation. I'm sorry for your experience with the Shapoko. I am grateful for your honest critique. Thank You.

 

If looking closely you may notice the V-slot is stationary in this configuration. Only the router, router mount, gantry plate assembly move up or down the Z-axis. The end plate on bottom of the V-slot is stationary also! The router case (top) will run into the Nema motor plate above! I'm going to run some test/example codes in wood anyway. I'm very excited!

 

E... thats Eccentrics not concentrics! I'm such a boob!

 

The need to feed and support a family consumes me presently. Things are usually winding down around the holidays, so I am grateful for the work, but dad-gum I want to play CNC wannabe real bad!

@Anthony Webb
I think this configuration would work superbly as a "pick and place"! I am only just learning so most anything I share is from that perspective. You may be able to eliminate spacer blocks but the clearance between gantry plate and c-beam is limited. I had to add additional precision shim between plate and v-wheels, plus shim the plate and nut-block, creating just enough clearance for the 5mm bolt heads that go thru bottom of plate and up into the t-nuts slotted in the spacer block you referenced. Hope that made sense? The bolt heads, thin as they are, are beneath the plate. Riding back and forth just above the c-beam. Without shim addition they rubbed the exposed V-wheel slots scarring them. If you do the same and the bolts up through plate...... Nope you need the t-nuts to thread into. Unless you can put nuts on top? Like if you had a nut inside those black angle brackets? Not sure that would work? Just playing that out loud for your perspective. You will find a way make it yours that is for sure.

One motivating factor for using the V-slot assembly on the Z axis was a desire to explore a V-slot bundle. I had three C-beam bundles already, and no prior experience with the hardware. Valuable decision too... for fact of revealing difference between a nut-block and the anti-backlash nut-block! V-slot bundle comes with anti-backlash nut... C-beam bundle has regular nut-block! I also thought the V-slot would get my router closer to the X-axis, but I'm not sure that is the case?

Although limited experiments in wood have exceeded expectations, my attention has focused on rigidity.
Not for necessity though! It's more like I'm tuning an engine to know or feel like I'm getting the most, or even more, from any given tool or machine. I probably don't need it... but I like to know it is there.

 

My first sign ever. Cheap 1/2 inch plywood I had laying around. Wishing I could get back all the scrap wood I ever threw away!