Masso G3 ATC build update - table, pneumatics, mount,

Over the last months I have been busy planning, designing, printing, purchasing, and building.
I thought some might be interested in my progress.
My main work has focused on the 8020 table and pneumatics.





The table is almost complete, except for the final leveling of the cast aluminum bed. I am hoping to get it within =/- 0.02 mm across the entire surface.

The pneumatics enclosure is complete, and includes my version of an MQL coolant/lubricant system.
On the outside, I have a separate panel switches for main power from PSU to solenoids/MQL electronics, and a separate switch for the power to the MQL system, along with the external dial to control the main flow.

Being an ATC spindle, there are a lot of connections (4 for the spindle), as well as air for chip evacuation both for the endmills as well as for the tool setter air knife.

The MQL system came through research of various great builders online. I did not want a fog buster, but because of the cost as well as I did not want to use air to control the fluid. I decided on a design that uses a peristaltic pump. I chose a stepper motor version, and added a small driver and PWM signal generator to control the steps/RPM/flow (The knob on the panel front controls the frequency/RPM).

I 3D printed a mount for the mister mixer valve to attach it to the Z axis, and the knobs will be used for fine-tuning the air/coolant mix.

I have a temporary set of toggle switches mounted at the front of the table to manually control the solenoids and MQL system, both of which will eventually also be software controlled.

I will be experimenting with spindle mounts, and my first tests will be with double 80 mm 1F mounts. I purchased two smaller linear bearings to use with this set-up to replace the longer ones. Initially mechanical tests give me about 75 mm travel. I anticipate this being adequate for my main work in wood and aluminum. I will start with this set-up, then perhaps switch to a single mount to see if there is any noticeable difference in cut quality.

Next steps will be to decide on the tool change system. One of the limiting factors is the clearance between the bottom of the Z axis assembly to the top of my aluminum bed - it is only about 112 mm with the Z assembly in its highest position. This does not leave enough clearance for me to put the tool holder forks at the back of the table in an ‘above table’ mounting which is customary. My solution is to use drop-in holders (see photo) vs forks, and drill holes through the table for the endmills to protrude through. My rough calculations show that the clearance will allow for standard length endmills as well as longer reach tooling that I plan to use for thicker foam/Styrofoam. The other alternative is to use tradition fork mounts at the front of the table, but I do not like the idea of not having a clear path to the front.

I am also designing a vacuum work holding system, but am still awaiting a few components to be shipped (sadly, still waiting on my VFD).

Much to do and test in the meantime however.

Happy to answer questions if you have any.

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Stunning
And for the minimum length…

Fan-Dabi-Dozi👍

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Hey Tom,

this is what I like to look at :slight_smile:

Excellent execution with a steep learning curve, that’s you. Congratulations. Envy you for the “pffft” “pffft” you can listen to now :slight_smile:

Thank you, and still so much to do! Your build will get there as well…it has to…because I’ll need your help! :smiley:

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Wow, SO professional looking Tom! Love it! +/- 0.02 would be quite an impressive feat. Love the telltale pencil marks where you place the T-nuts… got the same thing on mine! Did your alum. plate supplier make any claims to the squareness of the machined edges all around? Those might make good reference edges to set machine squareness from.

I just redid my frame last week, took it all apart & reassembled it within +/- 0.002" all-around. My steel plate has (4) 6mm reamed holes that I place dowel pins in to engage the extrusion. I used those same 4 holes to set squareness of the machine after it is attached to the frame. I also placed (2) 6mm dowel holes in the front Y rail blocks to set alignment to my front base extrusion.

@Aiph5u Glad to cross paths with you again, had not seen you post in awhile. Hope all is well in your corner of the world my friend! :slight_smile:

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Thank you Bill for the kind words. I found a supplier of the Alca5 plate not too far from where I live. They are a huge distributor that were willing to sell to me directly - when I backed my vehicle into their warehouse I was surrounded by huge piles of 4’X8’ and 5’X10’ aluminum plate 2-6" thick, and a stack of aluminum bar next to me that looked to be 12" diameter by 10-12’ long - impressive. My small plate seemed a little out of place when the fork lift put it into the back of the Jeep.

I had spent time affixing and squaring my Woodworker prior to picking up the plate. The front Y blocks were set equidistant from the front edge of the extrusion and I went from there. I do not have precision rulers/tapes so I just do my best to make it all square. The plate sits between the Y blocks so I won’t use it as a guide - I did check it and it was not a perfect square, which is fine as I did not specify that as part of the purchase.

I would have had all the holes drilled/reamed/threaded but that would have been very costly. Your use of fixture pins/dowels is a great system. My plan all along was to rent a mag drill and drill the holes, then use the flat countersink bits I bought to go back over the holes to recess the fasteners. I used a piece of steel plate I had to attach the mag drill - it ended up working, but it made me anxious putting holes in that plate and hoping it would line up with the T-nuts below.

It worked well, but to get it as level as I did I needed to use metal shims in places, which was expected but bothers me that the plate is not directly against all the extrusion lengths. I know it is solid and stable, but part of me is considering removing the shims, bolting the plate, then getting the nerve to slowly resurface and flatten the plate when my spindle is up and running. I ordered a special ISO 20 surfacing bit for aluminum with blade inserts, and after I test it on some aluminum bar stock I may use it to surface the plate. I don’t care about any raised perimeter edges as I don’t plan on machining or laying stock out that far to the sides.

Once I have everything up and running the plan is to get up the nerve to have my spindle put holes in the plate. The first set will be to attach a Saunders fixture plate with modular vice system. That will be my main work-holding for the aluminum pieces I plan to mill. If that goes well I could use that method to create accurate fixture pin reference holes. For wood work-holding I have in mind to make my own vacuum pods and experiment with those, but another idea is to make a removable wood spoil board. Much to do before that!

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Good plan Tom. It’s disappointing that the dimensional stack-up of mounting the alum. plate to the 80/20 doesn’t net better out-of-the-box flatness so that you didn’t have to surface it. But there are simply too many variables at play to allow that. I ran into the same thing with my build but the table is so much smaller that the initial error was negligible, but still there (around 0.05mm overall flatness, which I can live with).

I put a couple 12mm slots in my table for locating a vise and a parallel/stop. In addition, I put a 1/8" hole close to table center that I use to locate a few fixtures I work with, then assigned that point to G56.

I was considering stating again and removing all shims. One thought was to loosen some of the top extrusions to allow the plate to be drawn tight, then tighten the extrusions. Perhaps the plate will help the extrusions level as I work my way around. I am also trying to be realistic - if I can get it reasonably level, then my fixture plate/vice will hold the aluminum stock reasonably level, and I would surface the stock anyway. This would be true for wood as well - once on the vacuum pods I would surface my stock. If reasonably level ends up being several 1/100ths of a mm I think that would still be OK. Again, this is me speaking with absolutely no experience milling anything :grin:

Well, you most certainly have an engineering mind, regardless of milling experience. That level of knowledge will serve you well. I was thinking the same thing, that the alum. plate could aid in positioning/holding the extrusions flush before fully tightening up the extrusion frame fasteners.

Some of the levelness variation could come from the Onefinity itself, possibly very slight variation in the X & Y rail blocks and how they locate & hold the rails. All this makes checking the flatness of the table very difficult when you need to rely on the machine itself to hold the indicator while sweeping the base. You end up measuring a combination of both machine and base error. Surfacing the alum. plate will take a theoretically near-perfect plane (I know this cast aluminum tooling plate is very flat) and machine it to comply with machine and machine base error. What would be sweet would be to use some of their 2" thick tooling plate and have it large enough to capture the Y axis mounting blocks. That cost would be ridiculous though. When I had my X-Carve, I had played around with the idea of setting the machine on a “B” Grade 3" thick, 24 x 24 granite surface plate.

All this will be more than sufficient accuracy for just about any project you would do, short of NASA being on your customer list. :wink:

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My hope lies in your last comment :grin:

I had priced some of that larger size granite - oh my - but I do see some people build their CNCs from it.

One reason I did not go with a plate size to mount the entire machine was the tight tolerances of the holes it would require, and it would have to be a job outsourced which would have added cost and perhaps an unusable result. When I first got my 1F and began ‘exploring’ it I noticed that, as you said, there are inherent variations that could lead to measuring issues/inconsistencies - an example is the play between the screws that hold the tubes in place and the holes in the mounting blocks.

Another reason for not using an all-reaching mounting plate was that I designed my table to allow 4 M8 screws and T-nut pairs to be positioned at what I calculated to be the correct locations to mount the blocks to the extrusion. Before designing my table and purchasing the extrusions I bought a small piece of the 40-8080 material to test fit. I chose this one from the online dimensional drawings as the M8 screws and T-slots lined up perfectly with the Y axis block mounting holes. I am sure they rolled their eyes when in my order I stressed that 3 key extrusions had to be cut square to exactly 935mm!

When I had my steel plate initially made, it did span the entire machine. However, I decided (in whatever frame of mind I happened to be in) that I wanted an elevated machine table, so I modified it accordingly. With the dowel holes in the front Y blocks and still sitting on a fairly precision frame, I was confident in being able to assemble it to a reasonable tolerance. It’s nearly impossible to tweak in an X-Carve to the extent I have my Onefinity built.

We have similar table builds, other than yours being much larger. If I ever replace my steel table, I’d like to go with the same material you used on yours.

I wanted a raised base as well - it is 1/2" (12.7…mm).

One challenge I am having is getting the clearance I need for my automatic tool change design. I have the z assembly in its highest position, and unless I use extremely short endmills, it won’t clear the top of the tool holder pull studs when I have tools mounted along the back. I am currently designing a system of tubes vs forks. I will drill holes centred under each tool holder tube, so that longer endmills protrude through it. Masso has several preconfigured tool logics (I am envious however of the options in the Acorn - I must stop comparing them!), and one makes setting up a ‘drop in’ tube-like tool holder possible.

I very much like everything about my 1F hardware, but this is the first limitation I have found. I will be quick to say that these machines were never designed to work with spindles, or ATC set-ups for that matter. The good news is that is giving me another design challenge to solve, and more things to learn in F360 CAD! I also will start teaching myself how to use joints, and CAD files from manufacturers. I will need this to design and build a pneumatically actuated retractable cover to protect the tool holders and tool setter at the back. A member on the FB group who has a set up like mine, and much more experience, has been very helpful. He is going to use a dust shoe that gets automatically dropped off and picked up between tool changes. I just purchased the same one - from a maker in the UK - and I look forward to the challenge of setting that up as well. I will say my 3D printer is getting a work out as well during all of this. I am also designing custom clips, that will attach on top of my drag chains (they slide over the existing clips). These will be to hold all the air and water tubes, and free up space inside the chain for power/data/sensor cables. I think it may work, and it will let me keep by current drag chain mounts. I did upgrade to 18X50 drag chains which (may?) help.

I like your idea of how to handle the longer end mills in the holder, that seems like an elegantly simple and clean solution. ATC would be very cool to have. The 1F is definitely a worthy recipient of such a setup.

That is my belief as well

Hey Tom, hey Bill @Machinist,

just a few moments where I can express some thoughts I had reading your discussion

I find some valuable inspiration in your discussion regarding the workholding plate.

The problem of the loss of work area due to a fixed-position tool magazine has also concerned me. At the moment, I would tend to see a swiveling tool magazine as the solution (retracting cover included of course)

Yes, I feel this way too, regarding the front

yes, my feeling too. Limitations give challenges!

What kind of vacuum holding system did you think of for your machine?

Can you provide an image of this?

Some industry machines are made in a way that they change tools without retracting the dust shoe - but with Onefinity I think it would be the easiest way to make it retracted at tool change. Still the question where the ideal place for the tool change would be. I’m still uncertain about that.

It’s always admirable what Tom achieves, isn’t it?

@Machinist Hey Bill,
thanks for your kind welcome, have your E-Mail address, will PM you.

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Ah the joys of waking up to a thoroughly presented @Aiph5u post! :grin:

I believe my best option for tool change is the one at the back (I can pass on my calculations if you wish).
Basically…

Tool change along the Y axis would allow for 5 forks, with 12 cm between them (gives ~5cm buffer either side). This leaves I believe enough room at the back Y axis for the dust shoe docking (It is 10.920"/~27 cm end to end). Tool setter could be at the front set out from the line of the forks. Clearance for forks not an issue.

Tool change along the back X axis would allow for 10 drop in tube tool holders, and the tool setter would sit between them where I can’t drill through due to below deck support. I calculate 7 cm needed between tubes/tool holders with this configuration. If I ever wanted I could put a staggered 2nd row of tubes in front for more tool holders I don’t need or can’t afford. The dust shoe docking would be in front of this row on the Y axis at the back. I think this to be the best solution both to accommodate longer endmills/tooling, as well as an efficient layout with respect to speed of tool change steps. It also allows me to design and implement a cover to protect the tool holders/setter.

Tool change along the X axis at the front would be similar to back only it would use forks (no 2nd row possible).

Here is the dust shoe I bought…it has a hole for a M8 sensor…

For my vacuum hold down here is my plan.
I purchased a Gast rotary vane oil-less vacuum pump to create the vacuum. I also purchased a small aluminum tank to aid the vacuum pull. It will also act as a separator, but I also will have filters on each of the vacuum lines as well. I will have check valves/release valves in strategic locations. The manifold with 4 (currently) valves for 1/4" tube will be mounted on the unused space of the table at the back behind the tool holder tubes. I plan to make a set of vacuum pods that will be either milled from plastic to test, then aluminum later…perhaps. The pods will have holes to mount them to threaded holes in the cast plate. I have a digital vacuum switch to show state of vacuum, and I may use this to control a relay/pump to maintain vacuum if for some reason it lessens during a cut. I have other ideas as well, but that will be my plan to start. Here is one machinist whose work I like to follow, and this video shows something similar to what I am planning.

My z travel is somewhat limited at the moment because I am experimenting with a stacked 80 mm mounting system, however as I calculated the main issue for tool change is the low z assembly clearance. I have a forum member who plans to solve the problem by milling aluminum Y axis riser blocks. He has the same set up as mine but he bought the RoverCNC z assembly and is using a Journeyman.

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Amazing work on this build :+1: :star_struck:

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I appreciate your kind words. I certainly am learning a great deal, and solving the challenges that arise along the way. It keeps my mind off the fact that my VFD still has not shipped :grinning:

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