Hello,

I might be crazy, but reviwing my own list I noticed that the Nylon Nuts are missing on the Parts List of this build.
Can some one confirm?
I counted 32.

 

Hey MG, you previously mentioned that I should "definitely fuse each motor driver individually." Is that to say fuse each driver to ground? Or literally add an inline fuse between PSU and stepper driver in case of too many amps?

JB

 

Yeah, exactly. I use a 5A automotive blade type inline fuse between each driver and the power supply positive lead. Just for safety to prevent a fire in case a driver shorts to ground. Never put a fuse in the ground line, if you supply shorts out it may not protect the circuit. Also, there is a small voltage drop across the fuse, you don't want to have that in the ground lead.

MG

 

hi everyone,

trying the Estlcam on the c-beam,

can someone recommend the below settings for the Xpro v3 and c-beam xl kit

thx

steps per revolution

distance per revolution

max feedrate

 

Slowly getting my C Beam XL control box figured out. So far the high voltage side is complete and working flawlessly. I decided to keep the ATX in the tower so I could utilize the clean 12V, 5V and 3.3V lines for miscellaneous fans, lights and such. Also designed a bracket for mounting the stepper drivers , they are printing now. I will post pictures when they are done.

 

Stepper driver brackets printed with PLA plastic. Also created and printed a inline fuse holder for voltage to the drivers.

 

I've been using my C-Beam XL for about a year. It's my first CNC router and a learning experience but I've had much success routing projects in various types of wood. I use Fusion360 for CAD/CAM and my machine is controlled from a connected RaspberryPi3 running BCNC. I use the Pheonix controller w/DQ542MA Drivers. I love this thing and already considering converting to a longer Y-Axis... basically to a LEAD machine. Hey OpenBuilds, Maybe package that in a kit?


Lately I'm cutting some projects in Aluminum. I noticed an issue when routing an aluminum top plate for a tube audio amplifier requiring many circular 2D contours in a range of diameters and a rectangle cutout. The material is 6061 (Kaiser) aluminum from Metal Supermarkets @6.35mm thick.

I'm using an Amana Tool 51474 SC Spiral 'O' Single Flute, 1/8 D x 1/4 CH x 1/4 SHK x 2 Inch long up-cut router bit. It cuts smooth and leaves a great finish.

Here's my issue. All the cuts are 2D contours removing 0.5mm per pass @500mm/min w/the Dewalt 611 dial on the 4 speed setting. The first 2D contour is perfect and cuts through to the full 6.35mm depth. Each subsequent contour gets shallower and shallower.

My initial thoughts and possible causes:

1. The work surface maybe isn't true.
   -> I surfaced with a Whiteside 6210 spoil board surfacing 1" dia router bit a couple months ago, so prob not the cause.
2. The end mill could be slipping in the collet.
   -> It's the stock Dewalt 1/4" collet.
3. The router could be slipping in the mount.
   -> It's an OpenBuilds mount with a 3D printed PLA Dewalt spacer from Thingieverse.
4. The Z-stepper could be slipping/skipping steps.
   -> It's the OpenBuilds HighTorque motors - super strong so prob no?

IMO the culprit is either #2 or #3. Anyone on here have a similar experience with Z-depth minimizing over time when routing aluminum? Do most fellow OpenBuilders replace the stock Dewalt collet? Recommendations?

Let me know if you need more detail to help narrow down/troubleshoot.

Thanks ahead for insight and direction pointing.

Max

 

I have had exactly the same problem using a router by hand - the vibration caused by the flutes hitting the workpiece results in wear to the collet. If you are machining aluminium this wear will obviously be faster than if you were working with a softer material. Try measuring the length of tool sticking out of the collet before and after doing some cutting. Alex.

 

has anybody joined c-beams side=edge to side-edge. they will be meeting the uprights for x axis. I was interested in the middle area.

 

Mike

I'm working on a couple of designs using tandem c-beams. One idea I had is to mount them with the c-channels together, with a 40x40 in the resultant cavity. No way to bolt it together, but some good old 3M VHB tape should help. Also, nowhere to put the lead screw, but this is not insurmountable.

Putting a 40x40 in the channel on a single c-beam, with VHB tape in between and cast corner brackets tying it in top and bottom would probably be pretty strong as well. Again, no place for the lead screw.

I'm thinking 2 c-beams back to back (channels out) with a 1/4" aluminum plate full width in between would also work. That only adds stiffness in one direction, perpendicular to the plane of the plate, however. Doesn't do much for the other direction, or torsionally, which the c-beam is weak in. Adding a plate top and bottom as well would make it pretty strong. One of these days I'll have to learn to use the FEA in Fusion 360 and compare some of these methods.

Any of these methods would pretty much preclude the wheels/double plate gantry configuration, you'd have to use linear bearings to support the gantry plates instead.

MG

 

Hello all,

Long time listener (lurker), first time caller.

I was getting ready to order some parts and decided I should read this build first.

I am setting out to build my first CNC router, well - maybe second. I did build a bobsCNC e3 which I love. I just need something bigger.

My plan was a fixed gantry machine that would allow me to have work envelope of 24" X x 48" Y x 6" Z. I was planning on 1500mm members on the X and Y. My thinking was it would be large enough for my daily use and still allow me to tile jobs and process 4x8 sheet goods with rollers supporting the work in the fore and aft X direction.

For the spindle I was planning to use the 2.2 kw water cooled/VFD combo. I know this is heavy for a 48" span and intended to swap to a 1.5 kw or .8 kw if the deflection was too great.

The steppers will be NEMA 34 1200+ oz-in.

I was also planning on using OpenRail Linear Rail and RM2-2RS 3/8" V-Groove bearings throughout instead of the V Wheels.

I am going to be working with domestic and exotic hardwoods, softwoods, HDPE, Corian and non ferrous metals.

Given your collective experience with the OpenBuilds components is something like this worth pursuing?

Any input is greatly appreciated. If the 24" x 48" XY is not advisable I can drop to a 24" x 24" XY it just won't be optimal.

 

Several things come to mind.

• I would definitely not go longer than 1m X axis with c-beam components. In my opinion, it's just not stiff enough to handle any more length, even at 1m there is a lot of flex.
• a 6" Z travel is also very ambitious for an OB design. The OB Z axis support is not really sufficient for this length, and the longer moment arm will result in even more twist and X axis deflection.
• Your choice of NEMA34 motors is also not compatible with the stock 8mm lead screws. They would twist off the 8mm screws in a heartbeat. You would have to go to ballscrews. OB parts are designed for NEMA23 motors max
• Openrail is dated and being phased out, I would definitely not recommend it for new designs. Also, the steel v-groove wheels are not compatible with the aluminum openrail, it will wear out very quickly. Linear bearings would be a more appropriate choice.
• A fixed gantry moving table machine is not really compatible with your goals. Moving an entire sheet of plywood on a moving table and roller stands would be a nightmare. It would require serious motor torque, and would limit machining speeds drastically. Too much weight to throw around.
• a 2.2Kw spindle would definitely be too heavy and put too much force on the stock c-beam. Even a 1.5kW is a bit much. These machines are designed for 500-1000w spindles max.
• With all the modifications you are proposing, there is no longer any compatibility with OB gantry plates etc. You would have to design and build all new ones, which kind of defeats the purpose of using OB parts in the first place

You are talking about a machine that is in a 4'x4' or 4'x8' industrial class. OB parts are hobbyist grade and are not heavy enough for a machine of this size.

MG

 

Thank you for the input. I was really hoping I could use the OB items, they are very appealing. Maybe I will keep them in mind for a lighter duty machine in the future.

I was only going to use the OB extrusions and Linear Rail, everything else was going to be sourced elsewhere.

In your opinion is it worth considering extrusions at all for what I have laid out here? I was originally looking at 8020.net extrusions when I came across the OB ecosystem.

 

For your want list, I would definitely consider using 80/20 extrusions and either linear bearings or the v-groove wheels with steel track. That might be hard to find. Also, ball screws or rack and pinion drive.

Ambitious project for a first (well, second) timer. My suggestion would be just to buy a Lead Machine or Workbee kit and try it out, learn the ropes, and graduate to a larger machine later. Building a large machine like you want from scratch is not for the faint of heart. All the gantry plates must be custom made which will cost you dearly. Unless, you could make your own plates using a smaller machine...

Consider a kit from someone like CNCRouterParts.com if you have your heart set on a heavy duty build. Not cheap, but they make good kits.

Also, troll through the OB Builds section of the website, there are lots of good ideas there.

MG

 

I have been trolling through the builds for quite a while off an on, there are tons of things in there that have piqued my interests for sure.

As far as gantry plates and custom parts go; I might get a pretty good rate on one of his HAAS mills, possibly the VF-2. Nothing guaranteed, but if I buy the material outright he may be willing to help out.

I was originally going to do a welded steel machine with linear bearings / block bearings and ball screws and was looking forward to the challenge.

For the time being I will look at something like Joe's CNC vs. buying a kit from CNCRouterParts.com.

Thanks again for your guidance.

 

I have been watching his videos for several years now - that design is based on the Joe's CNC that I mentioned previously. Although Frank was basing his off of his friends who's is based on the Joe's CNC.

You could totally do it as well in a space limited environment, just make it shorter/narrower to suit your needs.

Thank you for the reminder about his channel.

 

Hey guys has anyone swapped out the stock 611 router for a water cooled spindle? Im currently building a noise enclosure for my cbeam xl and from what I've seen a watercooled spindle would help out a lot. What are your opinions on it? I'm concerned about the weight. For a 800w (1hp) spindle like https://www.amazon.com/Huanyang-Coo...D93XVDV8FZA&psc=1&refRID=T96FS5S33D93XVDV8FZA
The weight is about 8 pounds which seems to be a lot more then a 611. And with the added complexity of a vfd, and coolant loop is it worth it?

 

I'm not a big fan of the watercooled spindles.
Pros:

1. a LOT quieter
2. ER series chucks which can fit a large number of bit sizes
3. run at slower speeds than a router (easier bit selection, better for aluminum)

Cons:

1. hard to find router mounts for them
2. water cooling system is a pain
3. parts impossible to find
4. more expensive
5. generate a LOT of HF noise which can interfere with signals
6. previously were poor quality, newer ones are better

If you are stuck on a VFD spindle, I would recommend an air cooled one, much less complicated. Also, run shielded cable for motor, make sure shield is properly grounded, and don't run the cable in the same cable chain as the rest of your wiring.

MG

 

Thanks for the advice man, the noise is the main problem I'm trying to solve I'm making an enclosure thats a mdf box in a box with foam in between and in the inner box. But from what I saw I definitely need a vfd to get anywhere near quite even with a good enclosure. And thanks I definitely am gonna get some double sheilded cable off mcmaster but I didn't think about not running it In the same energy chain as the rest. I was thinking water-cooling because I have a bunch of stuff laying around for PC water-cooling (pump, res, a 240mm thick rad from ek and 4 120mm fans) from my old rig. I figured I could resuse it and not have to by anythine besides fitting and tubing. I am worried that the watercooled one I found from huanyang is gonna be bad because so many people seem to say it's very hit or miss. I also can't seem to find what the fittings and tubing sizes are on it.

 

Yeah, the water cooled units seem to be an older design, and thus a bit less reliable. Newer ones that are air cooled may be better, but I have not used one. Also, keep in mind that the noise generated is mostly from the bit cutting the material. A Dewalt router is actually fairly quiet when its not cutting anything. A quiet spindle motor is not going to help as much as you think.

I don't think you need double shielded cable, but it might help.

As far as quietness, just a single MDF enclosure lined with sound absorbing material like dense foam rubber would be enough, I think. There is a product called Mass Loaded Vinyl that is made to be sandwiched between 2 sheets of dense material that might work. Also, there is sound deadening drywall available. Standard styrofoam doesn't do much for sound absorption, except at high frequencies. A good dense foam rubber like carpet underlay might work better. Density is the key. Also, sealing the enclosure against air leaks is quite important. Sound can leak out of an enclosure through small gaps and holes, seal everything up with a good silicone sealant and use a good door gasket.

What the heck? do you want to operate the machine in your living room or what?

MG

 

Unfortunately the living room is **** close haha. I'm moving and am losing my access to a shop because of it (I used to leave it at my awesome friends machine shop). So the idea is to run it in the house for a bit while I'll try and find a better place for it. And after a bunch of research what you said is exactly what I found. I'm gonna try an MDF box in a box with mass loaded vinyl in between and seal it up tight. I am worried about the heat due to lack of airflow into the box but if that becomes an issue I'll figure that out.

 

I don"t know if its just me, but the c-beam xl has disappeared from the openbuilds web site. I was hoping to order one when my tax return gets here next week.

 

Not there from what I can see.

 

You can always just order the parts individually from the BOM and build it yourself. Probably not selling well because everybody wants the Lead Machine or Workbee. Try contacting the store people, maybe they'll make one up for you.

MG