best method for interfacing linear square rail to 80/20 framing?


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Thread: best method for interfacing linear square rail to 80/20 framing?

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    Default best method for interfacing linear square rail to 80/20 framing?

    Im in the design stage of my diy machine and trying to decide on the best method for attaching my 20mm square linear rail to extruded aluminum. Im still not 100% clear on the bolt size for attaching my rails since i havent received it yet. The online spec sheet lists an m5 bolt, but the technical drawing shows a 6mm hole. Anyway, im wondering if its sufficient to bolt the rail directly to the extrude, or is it better to sandwich an aluminum plate in between. If its an m6 bolt, i can use the 50mm x 100mm extrude which has slightly over 6mm slots in it, so i feel that without an aluminum plate in between, it should have a pretty stable mount directly to the frame with a bolt into the t-nut inside the frame. Has anybody had success with this method? Or is it much better to have a flat plate in between the frame and rail? Thanks

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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    My preference would be to use a plate, although I have seen pictures of it done both ways.

    My first build used T slot mounted on a steel frame with IVT rails and V groove bearings. My current build doesn't use any T slot, mostly steel tube. So I have not mounted square linear rails to T slot myself, although if I did, I believe using the plate is the best of the two ideas.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    I think 50X100 extrusion has 10mm slots so if you bolt directly you 're only sitting 5mm each side. The aluminum plate would be nice, especially if you get ground tooling plate. If you don't use plate, you ca get continuous t-slot pre-tapped at the same spacing as your LM rail. I'm pretty sure it's M6 for 20mm and 25mm and M8 for 30mm and 35mm.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    sounds good, i agree. using the flat plate should ensure a nice accurate flat plane mount. Really wont be expensive or hard to do. Most likely just order some 1/4" x 2-3" stock, and drill some slightly larger holes in it on a drill press for the bolts to pass through. Now i just need to decide how to orient my x rails. The y and z rail mounting seems pretty straight forward in my head, really only one way that makes sense for that, but for x axis rails i cant decide if i want them laying flat on the top of my frame, or mounted sideways on the outer side of my frame. It will be a dual screw, dual stepper x setup. Mounting the rails on top will make adjustment easier since the rails will already be on a flat plane with eachother and slight side to side adjustment can be made to get them perfectly parralell before tightening down, but the downsides are more debris getting on them, and also i cant think of a great way to place the ballnut on the gantry. I guess a flat plate will just have to be extended downward from the side of the gantry to mount the ball nut on. mounting them on the sides will keep them away from debris and i can picture a good way to orient the ballscrew and nut, but adjustment becomes more difficult since it needs to somehow be adjustable up/down and side to side. also i feel like theres more chance for the rail to shift during heavy load and vibration with them mounted to the side. Im not sure how secure they will be just with the clamping force of the bolts squeezing the rail against the plate and the plate against the 80/20. i suppose once its adjusted i can wick some green loctite retainer in between the faces to make sure it never shifts, but it would be nice to leave it so its still adjustable.

    any thoughts on mounting the x rails on top vs on the side?



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    Without a CAD file to look at it's difficult to give you design advice. Personally, I'd mount the rails on top with a T-Slot design.

    For the gantry ballscrew, you will either need to mount it on top, or between the rails, or at the back, or below. Between the rails or below would be the best choices, however I have never seen anyone sort out the geometry to mount a ballscrew below the gantry. It could work well, but there is more chance of debris getting into the ballscrew. Some very successful commercial designs have rack and pinion driven from the top so I'm not certain how important it really is where the driving point comes from. IMO, lower is better but everything in design is a trade off.

    Some big VMC's have the ballscrew between the rails, but closer to the bottom rail. That is what I am doing with my design.

    This requires an offset (spacer) from the tube,

    If you want better design advice than you need to either

    1. Look at some designs that have worked well and copy those

    or

    2. Do a design log, and post some pics of your CAD models, and ask for feedback

    T-slot isn't the best material for a CNC. It works OK, but not like steel. Consider filling your tubes with epoxy granite or bolting some steel stiffeners to the unused faces.

    I looked though your other thread, how big is this machine?

    5mm lead ballscrews generally isn't a good choice. So you will be looking for low inductance steppers and the highest voltage power supply you can use, assuming whip isn't a factor.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    This will actually be a dual screw/dual stepper X axis setup like I mentioned earlier. It sounds like you are giving examples of a single screw setup unless I'm misunderstanding. The machine will actually be pretty small. My linear rails are 1000mm, 700mm, 400mm, but I plan to use pretty wide stances with the carriages for good stability. Shooting for a work space of 650mm X 400mm x 200mm. So the total width of the gantry side will be 350mm on outside of carriages, leaving 650mm travel.

    I tried to put mechanics together with 1610 screws but I just couldn't make it happen for my price range. I only paid 500 total for all 4 screws, end supports, all 6 20mm rails, 12 carriages, couplers, and ball nut mounts. With 1610's, I couldn't find a full package like this and it was already coming to like 600 just for the linear rails. I'm hoping the 1605's don't take away from performance much.

    Speaking of which, why are the 1605's considered a bad choice? I would think that should give me better torque and precision, but less speed. Not sure if I mentioned it, but this is just a hobby machine that I'm looking to cut carbon fiber parts with and some aluminum parts now and then. Speeds are not important. Definitely not looking to make money with this. Do the 1605's have less precision?

    I've been talking with vince (corvetteguy50) which has an eBay store and might be getting the electronics package from him. 4x 300oz nema23, gecko 540 on 48v, 1.5kw spindle, uc100, as well as all the cables I need. He also has 600oz steppers but I feel like that's overkill for this. I can still upgrade to those for like another 80 bucks if you guys think I would benefit from 600oz steppers.

    For the size of machine, I think I can get decent rigidity from the 80/20. I really don't need insane tolerances for what I'm doing with it.

    At this point in think I'll just start drawing and posting some pics for input.

    I am curious on the 1605 vs 1610 thing, so it would be great if you guys could shed some light on that. Also let me know if you think I would benefit from going up to 600oz steppers. The 300's are about 2mh inductance and the 600's were around 6mh.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    Quote Originally Posted by QuinnSjoblom View Post

    I've been talking with vince (corvetteguy50) which has an eBay store and might be getting the electronics package from him.
    errrrrrrp. full stop. Dog got some issues maaaan. He ride the short bus.



    Never seen a bigger d******** on YouTube who likes the sound of his own voice in my whole life. Yes, I've watched (painfully) several of his videos.

    Dude made a video about how to pick the correct stepper motor and yet has no idea or concept on how to do the math. OMFG! Serious fail! He won't find any sympathy here.

    Probably the worst person you could ask for advice on anything.



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    Quote Originally Posted by NIC 77 View Post
    errrrrrrp. full stop. Dog got some issues maaaan. He ride the short bus.



    Never seen a bigger d******** on YouTube who likes the sound of his own voice in my whole life. Yes, I've watched (painfully) several of his videos.

    Dude made a video about how to pick the correct stepper motor and yet has no idea or concept on how to do the math. OMFG! Serious fail! He won't find any sympathy here.

    Probably the worst person you could ask for advice on anything.
    Hmm, OK good to know. Havent really been talking with him so much for advice, rather seeing what he has and putting a package together. Should I be worried about ordering from him? Really the only thing up in the air about what I order based on his advice is the stepper choice. The g540, uc100, psu, 1.5k spindle, and cables are pretty straight forward choices that I came to on my own. Seems to be a good deal for what I'm getting. Basically same price as getting it all elsewhere, but only one shipping charge so saving quite a bit. He does have 100% positive feedback and I don't see another place to buy everything in one shot. Seems cheapest and most convenient whether he knows what he's talking about or not. Just need to decide on which choice of stepper.

    One of them is 300oz, 3.5a, 1.8 degree step, 2.4mh inductance.

    The other is 600oz, 3.5a, 1.8 step, 6.4mh

    I'm assuming 300oz should be plenty, or should I go 600oz?

    Also still curious on the cons of using 1605 screws



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    Provided your LM rails have 4 sets of races you can pretty much mount them any way you like.

    As to screws, depends on how big the machine is and what you're doing with it. Smaller machine, under 2' X 3", I'd say go with the 5mm pitch and use the smaller steppers. Larger machine, use the 10mm pitch and go with the larger steppers.

    I personally feel if you don't need more than 200-250ipm rapids then the 5mm pitch should be fine. Because of the efficiency of the ballscrew, they're easier to back-drive as opposed to ACME. Meaning, for coarse-pitch ballscrews, you may need a larger stepper than you think to prevent any "jolting" forces from causing the stepper to lose position. However with a larger machine, having a higher rapids speed may be desirable, and if you use the 5mm pitch, whip becomes a problem unless you move to the next size diameter screw - which complicates things a bit because now a larger stepper may be needed just to overcome the inertia of the screw and give reasonable acceleration. Here, the coarser pitch screw would require less stepper RPM to attain the same rapids speed, thus mitigating whip.



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    Quote Originally Posted by louieatienza View Post
    Provided your LM rails have 4 sets of races you can pretty much mount them any way you like.

    As to screws, depends on how big the machine is and what you're doing with it. Smaller machine, under 2' X 3", I'd say go with the 5mm pitch and use the smaller steppers. Larger machine, use the 10mm pitch and go with the larger steppers.

    I personally feel if you don't need more than 200-250ipm rapids then the 5mm pitch should be fine. Because of the efficiency of the ballscrew, they're easier to back-drive as opposed to ACME. Meaning, for coarse-pitch ballscrews, you may need a larger stepper than you think to prevent any "jolting" forces from causing the stepper to lose position. However with a larger machine, having a higher rapids speed may be desirable, and if you use the 5mm pitch, whip becomes a problem unless you move to the next size diameter screw - which complicates things a bit because now a larger stepper may be needed just to overcome the inertia of the screw and give reasonable acceleration. Here, the coarser pitch screw would require less stepper RPM to attain the same rapids speed, thus mitigating whip.
    Ok, sounds like for my application, the 300oz steppers and 1605s will be fine. Very small machine. Working area will be only 650mm×400mm (26inch X 16inch).

    I can't stress this enough, this will be a hobby machine that will be milling very few parts and I absolutely do not care about fast rapids, crazy feeds, or mass production. If I can mill a basic 40mm X 40mm bearing block out of aluminum with a pocket for a bearing in it within a couple hours, I'm happy. Faster would be nice, but not important. I never plan on making any kind of money with this machine. I just want it to have decent precision. Main purpose is for designing and prototyping rc helicopter parts out of carbon fiber and aluminum. Possibly mill some large foam plugs for making fiberglass canopies.

    I guess placing this in the wood router section may have caused some assumptions that it was a bigger router that I wanted to produce with. Couldn't really find a more appropriate diy machine section to ask about the rail mounting orientation in.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    The 600oz motors will much less torque at high speed than the 300oz motors, because steppers lose torque, as rpm's increase. The higher the inductance, the faster the torque falls off.

    The issue with 1605 screws is that you need to spin them fast, if you want your router to move fast (which you do). You need 5 revolutions to move 1 inch. Most steppers have a max usable rpm in the 800-1200 rpm range, which means a max speed of ±240ipm.
    So, you want the motor with the highest torque, at the highest speed, which would be the 300oz motor.


    If possible, a 2.2Kw spindle with an ER20 collet is a much better choice, as the larger collet gives you a lot more tooling options than the ER11 collets in the 1.5Kw spindles, which can only hold 1/4" bits and smaller.

    Gerry

    UCCNC 2017 Screenset
    [URL]http://www.thecncwoodworker.com/2017.html[/URL]

    Mach3 2010 Screenset
    [URL]http://www.thecncwoodworker.com/2010.html[/URL]

    JointCAM - CNC Dovetails & Box Joints
    [URL]http://www.g-forcecnc.com/jointcam.html[/URL]

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    I can't stress this enough, this will be a hobby machine that will be milling very few parts and I absolutely do not care about fast rapids, crazy feeds, or mass production. If I can mill a basic 40mm X 40mm bearing block out of aluminum with a pocket for a bearing in it within a couple hours, I'm happy. Faster would be nice, but not important.
    I can't tell you how many people have started out with the same assumption, and changed there mind when they see how slow it is.

    But you should be fine with the 1605 and 300oz motors. Not super fast, but not terrible either.

    Gerry

    UCCNC 2017 Screenset
    [URL]http://www.thecncwoodworker.com/2017.html[/URL]

    Mach3 2010 Screenset
    [URL]http://www.thecncwoodworker.com/2010.html[/URL]

    JointCAM - CNC Dovetails & Box Joints
    [URL]http://www.g-forcecnc.com/jointcam.html[/URL]

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


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    Quote Originally Posted by ger21 View Post
    I can't tell you how many people have started out with the same assumption, and changed there mind when they see how slow it is.

    But you should be fine with the 1605 and 300oz motors. Not super fast, but not terrible either.
    Excellent, thanks. One thing to consider is that the amount of money I spent on the full mechanics package (500 bucks) is no more than it would have cost me to buy just rails and carriages by themselves, so if later on I decide faster speed is important, I can get 1610 screws (just the screws, support blocks from 1605 will still work) and I'm not spending anymore than I would have doing it in the first place. I will design my machine so it's possible to make slight changes to the distance between screw support blocks in case I get different screws later on that might be slightly different length.

    I have a design feature in mind that I want to run by you guys. Pretty simple concept, but I haven't really seen it. My main rectangular frame will most likely be 100mm tall 80/20. I would like to design it so a 3/4" sheet of mdf bolts to the top of this for cutting carbon fiber sheets. Then I would have my t slot table mounted to the bottom of my main frame. Mdf could be removed and the t slot table surface is about 4 inches lower. This would allow for a vice to be mounted at the lower level to bring an aluminum part up to about the same level my mdf surface would be. Advantage of this would be that a don't need a ton of z travel to allow for the height of a vice being attached to my main table surface. Could this work well or is it a bad idea? It's not a requirement for me to get the travel I need, but it does make things more convenient. My z linear rails are 400mm so I could have as much as 250mm actual travel (10") with a 150mm stance on my z carriages. But if I use my idea, I don't need nearly that much travel. 200mm would be more than enough and would actually give me more useable workspace when bolting down a vice to the lower level. That would give me a wider 200mm stance with z carriages and the whole gantry assembly could be kept lower with better stability. I do realize that this greatly reduces my useable table space when using a vice since the vice needs to fit in between the sides of the main frame, but any aluminum part I would be milling would be no larger that let's say 75mm×75mm, and that's a pretty huge part for even a large rc helicopter.

    Last edited by QuinnSjoblom; 11-20-2017 at 10:15 AM.


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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    If you're going to make an investment down the road for faster performance down the road, an upgrade to step-servos (or easy servos as they're called), or even the ClearPath SDSK servos, keeping your screws, would be a better choice.

    There are some very specific examples of where you'd want faster rapids in a smaller machine, but mainly it's up to the CAM and the way you organize the toolpaths that have a better impact on overall machining speed. Specifically, the more the cutter stays down cutting and the less time it spends in air, the faster the machine will be overall regardless of rapids speed. At the tools sizes you'll likely use, you won't be machining anywhere near the potential rapids speeds. One extreme example of bad programming would be machining two rows of holes, on a plate spanning the entire length of the machine, with each row on opposite ends, going back and forth hole to hole. The CAM wouldn't do that, it would attempt to find the shortest path which would be drill the first row, left to right for example, then go across and drill the second row, right to left. In 3D machining this is not always possible, depending on the design.

    Your vice concept isn't new, so there should be no issue with that. However, you don't always need a vise (which would require a set of parallels for thinner stock anyway.) You could always screw the aluminum plate down on the edges, then CNC holes to hold the plate down before further machining. Also use the holes in your parts for hold-downs by running a screw or bolt through them. Another option would be to mill grooves onto the MDF, install t-slots, and use a quick-vise, which are two separate parts of a vise that get clamped down on the t-track.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    Apologies for the earlier outburst.

    I just really don't like the way that guy has mocked other people's vids. I hope he got their permission to use them in his videos. Simply making fun of others then posting some videos of an industrial quality machine does not an expert make you.

    I criticize designs all the time, but it is either for someone who is looking at buying a machine from a company, or for someone who is looking to improve their design. Not making fun of someone's build who has perhaps no knowledge that I'm doing it and no opportunity to respond.

    I prefer to find examples of people who have done things well. I find that to be a classier approach.

    So enough on that subject from me.

    Quinn, if you look at this thread, post #27, you can see some theoretical mathematical performance predictions using a certain Nema 23 based on the provide torque vs speed graph.

    http://www.cnczone.com/forums/diy-cn...126-cnc-3.html

    The second thing is the critical speed

    Metric Critical Speed Calculator | Nook Industries

    So looking at the Nook critical speed calculator (which can be over conservative depending on how straight the screw is), and using an end fixity of B and a 950mm bearing to bearing length for your longest screw, with a root diameter of 13.5mm (for a 16mm screw) we get 1809 RPM max.

    5mm / rev x 1809 RPM = 9045 mm /m = 356 IPM

    The Nook calculator can be over conservative as mentioned, and that is a respectable speed to do a wood carving at (if your machine is rigid enough for it). As Louie mentioned, you could perhaps upgrade to something like a clearpath in the future to get up to that speed or even a bit more.

    So what this means is that you need to be careful about selecting your steppers and drivers, and a higher voltage power supply (if your drivers can handle it) will give you better speed characteristics.

    I believe A_Camera is using Nema 23's and 5mm lead ballscrews and getting good performance, so it can be done (although I don't consider it to be the norm), you just have to be careful about selecting your components. Some Nema 23's will run up to 2K RPM with useful torque, others, perhaps half that.

    Also, as you can only input one value for acceleration into the software, the torque at the maximum RPM you can run at becomes the deciding factor. All things considered, my preference is to use 10mm or more as a lead, and not try to spin your screws at really fast RPM's. As far as precision goes, the resolution for either, with microstepping will be less than you need to worry about, and even the smallest amount of backlash or runout in the spindle will dwarf that error.

    Yes, if you got all your stuff (and if it's good quality stuff) for $500, that's a really good deal.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    Thanks for the input guys. Good stuff. For now I'll build the machine with the 300oz steppers and 1605's. Sound like I can get plenty of speed for my needs without worrying about whip or other issues. I'm guessing this won't be the last machine I build. Been in The rc heli hobby for about 5 years now which I love, but I'm running out of things to blow my money on. Probably spent 5k at least per year on that hobby the last few years. I'll probably gain some experience and learn some lessons on this machine, then possibly start fresh on something bigger, better, more expensive in the future. Also the ability to machine parts for the second one will be nice. I think for the 1500 total I'll have in this first machine, it should perform decent. Definitely better than the 3 grand I originally planned on dumping into a stepcraft. So glad I didn't go that route! Learning a lot more going diy anyway.



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    Your feed rates really aren't determined by you so mach as they are by the spindle speeds you have to work with. In other words spindle speed, the number of teeth on the cutter and the optimal feed per tooth determine how fast your feed rates should be.

    On machines that use routers with high minimal speeds your feed rates will be much faster than on a conventional milll like a Bridgeport. At least they will be if you want to optimize tool life.

    The good thing here is that there is some variability in parameter selection. For example you can find end mills with one to eight cutting flutes. It is also common too sacrifice tool life for surface finish.

    In any event i don't think you will have feed rate problems with the materials you intend to cut. I just want you to avoid dismissing the importance of hitting optimal feed rates.

    Quote Originally Posted by QuinnSjoblom View Post
    Ok, sounds like for my application, the 300oz steppers and 1605s will be fine. Very small machine. Working area will be only 650mm×400mm (26inch X 16inch).

    I can't stress this enough, this will be a hobby machine that will be milling very few parts and I absolutely do not care about fast rapids, crazy feeds, or mass production. If I can mill a basic 40mm X 40mm bearing block out of aluminum with a pocket for a bearing in it within a couple hours, I'm happy. Faster would be nice, but not important. I never plan on making any kind of money with this machine. I just want it to have decent precision. Main purpose is for designing and prototyping rc helicopter parts out of carbon fiber and aluminum. Possibly mill some large foam plugs for making fiberglass canopies.

    I guess placing this in the wood router section may have caused some assumptions that it was a bigger router that I wanted to produce with. Couldn't really find a more appropriate diy machine section to ask about the rail mounting orientation in.




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    You have gotten some good advice so im going to add a few points or opinions that might help.

    First if you are talking true 80/20 extrusions i find them less than optimal for linear rail mounting. For one thing the faces of the extrusions are not flat, 80/20 does this on purpose but is makes mounting narrow linear rail problematic. If your rails are wide enough to span the higher parts of the section you are likely buying more rail than needed. There are a number of other issues with T-Slotted extrusions in general.

    Some extrusion manufactures like Misumi offer a grinding service to give you a better mounting surface for linear rails. Generally this is offered on heavier extrusions. This is something worth considering.

    Personally though id go with a sub plate mounted to the extrusion. That is if i where to use extrusions at all.

    In the end it really pays to consider steel especially for the gantry. The reason is strength and costs. Prime aluminum is expensive, with a lot of pricy add ons required. If you can pick up steel drops you will likely find a suitable gantry beam for 60 cents a pound. I mention the gantry here because it is a common weak link in many designs.

    As for you inset vice design, approaches like that might be more common than you realize. Often this approach is used to support a fourth axis. There are problems but each can be over-comed. First it is likely that the MDF will not be stiff enough to span the distance alone. No big deal as you can stiffen it in a number of ways. The second problem is keeping the support extrusions for the X axis from moving laterally. Normally this is handled with angle brackets or full height end pieces. However if you want to keep the interior clear you quickly run out of space for the linear drive components.

    Lastly a little safety advice, if you expect to do carbon fiber build a totally enclosed machine with dust control!!!!! Yeah this adds a bit to the cost but if you plan ahead it can be an integrated solution. Actually dust control should be thought about for machine life span, dust in the drive components will lead to early failure. This means putting thought into how linear components are mounted and protected.



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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    interesting, didnt realize misumi offered milled surface extrusions. I was planning on using aluminum plate in between the extrusion and rail for the reasons you mentioned, but it sounds like maybe i can eliminate the need for the plate if i go with the milled surface misumi. I never really considered steel as an option because i have no way of working with it, unless there are companies like misumi or 80/20 that can give me custom size pieces.

    As for the carbon fiber, yes really nasty stuff. i plan on having 2 levels of dust collection. Ill have something right over the spindle sucking it up as well as a full plexiglass enclosure around the machine that i will pull air through into a filter of some sort.

    If i was to consider steel, how would i go about constructing it that way? is that just assuming i would be able to cut, mill, drill holes in it? Not really possible for me unless there's pieces i can buy that work as is.

    one thing to add, ive decided against the dual level table for dropping the vice down for a couple reasons. As others have pointed out, its not hard to get creative with fixturing which eliminates the need for a vice in most cases. This will be dual drive x, so having to drop down the mechanics underneath isnt relevant since i wont have them, although with the dual level design i cant use as many cross supports in between the side frames. originally i had planned to still use them, but leaving a partial section open in the middle without cross beams to give a small area to drop a vice down. Anyway, doing away with that idea. Ill have a regular table top. Im thinking multiple sections of 25mm x 75mm stacked together to create a t slot table. much cheaper than buying an actual solid aluminum t slot slab. Using the milled surface misumi is now an option, but i had also considered maybe just surface milling my table once its all build to get a nice flat surface without the portions that dip in on either side of the t slots.

    Off work for the next 5 days so plan to start drawing my cnc in fusion 360. Ill post once i have something. Im sure alot of my ideas will be shot down and better suggestions given. Thats what you guys are here for. Also it looks like all my ballscrews and linear rails arrive friday so thats exciting! Cant wait to check them out

    Last edited by QuinnSjoblom; 11-21-2017 at 06:57 PM.


  20. #20
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    Default Re: best method for interfacing linear square rail to 80/20 framing?

    I'd be interested in seeing a price comparison between regular 8020 T slot and Misumi ground flat T slot.

    Have you seen any builds using it Wizard?

    Cutting steel isn't too hard, you can do it with an angle grinder, but it is much easier if you have access to a large bandsaw. Getting things flat is where steel can be tricky.

    Not too hard to drill and tap some holes, but as a minimum you need a good variable speed drill press. A simple hand drill isn't good enough. I use a small mill.

    The other option is to use aluminum extrusion, and I'm not talking about T-slot. I'm talking about square aluminum tube, perhaps 3/8" wall thickness, not to hard to drill and tap some holes for your rails, and you could fill it with something afterwards like high density polyurethane or epoxy granite, you could even press in so ribs made of plywood. IMO, performance wise, that would be superior to T-Slot, and cost wise it might be on par. You'd have to make some inquiries to see what is available, and visit the metal merchant with a long straight edge to see if it's flat. IMO, aluminum products are typically flat enough for our purposes.

    If you do this, please report back, I'd like to hear the results for cost and flatness. Also, look at the price for a full length from the wholesaler, and you'd use the rest for other parts of the machine, otherwise the cost may be double for what you get.

    Aligning the rails and drilling / tapping some holes is really a joke - not hard to do, but like I said, you need at least a good variable speed drill press.



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best method for interfacing linear square rail to 80/20 framing?

best method for interfacing linear square rail to 80/20 framing?