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It is CUTTING! Bolted Mechmate with linear bearings - Kansas, MO
OK, I've been on this forum for almost a year, completed the kitchen sink project a while ago, but the build of the structure of the machine has taken longer than planned.
My machine is a little different than most here. As the title suggests, it is a bolted together construction, but I did weld the major subassemblies. Basically, i wanted to be able to assemble/disassemble by myself or with the help of one person. I've actually done that by myself a few times now. I'm also using linear bearings, as before I found this site, I had purchased a set of those. This limits my table to about 6' of X travel (Y is about 4' and Z will be about 12"). In modifying Gerald's plans to allow the use of linear bearings, I tried to make it so that I could go back to V-bearings if I had the need for the full 8 foot of X travel. Sorry about the red color, but the price was right. A friend who owns an autobody shop had a gallon of 2 part enamel he didn't need, and offered it for free. Here's some pictures |
#2
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Looks great, where did you get your parts cut? With me living in Kansas too it would be useful to find a local place to get parts cut for the build.
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#3
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I used the Joe Mclain parts (Sweet Home Alabama). Didn't even attempt to source it around here as his price seemed reasonable.
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#4
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Kevin,
She's beautiful. Congrats. |
#5
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Congrats on a really nice table. WIth that nice Red color, maybe some pinstripe or flames would be in order?
Very nicely done. |
#6
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Kevin,
Great looking machine. I like the red paint....makes it feel fast, like a Ferrari Wayne |
#7
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Kevin,
Nice bright color. Why did you decided to go with linear rails and bearings? |
#9
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Thanks for the positive comments. As for why the linear bearings, as I said, I had somewhat planned a build in my mind using them before finding this site. Mainly because of their perceived precision. It will be interesting to see what kind of precision and repeatability I can optain when complete.
Gerald, you bring up a good point. While it is not difficult to move my gantry or Y-car, there is definitely more friction than with the V-bearings. I would think the mass, and therefore the impact on acceleration/deceleration would be a larger impact on overall speed, but no doubt the friction will come into play. Oh, from what I was told, it is Porsche red, so I guess it should at least LOOK fast. |
#10
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Kevin, I have some experience of using a linear bearing in the z-slide of the first MechMate. It has worked perfectly since day 1 and hasn't needed a moment's attention since. So, I can only speak well of linear bearings so far. That is why I will be looking at your results with keen interest.
Can't see from your photos, but remember to put the plugs into the rails over the screw heads. Most cases where I have seen linear bearings being used, those plugs were not fitted. Without the plug, the seal cannot wipe the top of the bearing rail clean. |
#11
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Kevin,
Nice machine! |
#12
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Did you factor in the cost of all the traffic tickets you get with a red machine?
Looks REALLY great! |
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Gerald, none of my rails came with plugs. Are they just a press fit piece of plastic?
I looked at your original design with the linear bearing z-axis. I had in mind something similar. From the pictures, I do not see any spring to maintain contact with the rack. Did you use a spring, or more of a fixed mount? Thanks. |
#14
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Yes, they are just press-fitted plastic. You press them in with a plate over the top to get the plug perfectly flush with the rail. Good rail suppliers will supply the plugs with the rail - didn't any fall out of the box when you unpacked yours?
The spring is very visible in this post. |
#15
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I see the spring now. Thanks Gerald. I bought these some time ago off of Ebay. I'm fairly sure there were no plugs, and it's too late to complain now. I wonder if I could find a plastic rod of the correct diameter, and cut it down into little plugs?
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#16
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Suppose you could also pour some filler into those holes and then slice off the excess once it has set?
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#17
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Different Z-slide approach
I think what I'll do is put something "soft" in the bottom on the hole, such as modelling clay, then top off the hole with epoxy or filler. That way if I need to get the rail back off, I can.
Some more progress to show. Here is my Z slide assembly. It's entirely aluminum to try to minimize moving mass. As you can see, I will have up to 30" of travel by unbolting the cross members. The linear rails bolted to the aluminum plate add quite a bit of stiffness, but I am still concerned with flexing while traversing under load in the X-direction. I have about an inch of clearance on the back side of the plate to add a T or U section for additional stiffness. It still needs some refining, but you get the idea. |
#18
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Different Z-slide approach
Opps, sorry about the pictures being sideways. Is there a way to edit the pictures once posted? Fixed since
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#19
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Try waxing the holes with a q-tip and filling them with Sika-Flex. It is usually used to fill expansion joints in concrete. It remains rubbery forever and it is very easy to use. Just squeeze from a caulking tube. Awesome stuff. Available at concrete supply houses.
BTW: Your machine looks great!!!!!!!!!!! The only thing that would improve it is a little blue paint. Sorry, I couldn't resist. |
#21
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hi,
my question might be a little bit naive, why do you need such long z-axis? |
#22
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I´ve had a couple guys express interest in having me cut foam molds for race car and custom car body panels. Plus, the incremental cost was insignificant. As I´m set up now, my z travel is only about 11 inches. If and when one of these jobs come through, I will make modifications for 24 inches.
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#23
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This is my first post....
Congrantulations... my friend this is beaudiful |
#24
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Thanks Jonny. I am on vacation in Brazil right now. Will post some more pictures when \i get back. I hope to be cutting within a week or two after returning. Don´t tell my wife that I am suffering withdrawals from working on the machine.
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#25
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Where? |
#26
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Maragogi
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#27
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2.500 Km
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#28
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Wow, Gerald has got a memory like a steel trap! Yes, we are in Maragogi. About 120 kilometers south of Recife. I´m curious, the guys from Brasil, what kinds of things are you going to be cutting with your machine?
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#29
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Wood and aluminum ... Gerald although not like this material
Aluminum: http://br.youtube.com/watch?v=nGH6kT...e=channel_page and future: http://br.youtube.com/watch?v=w28SzD...eature=channel and before: http://br.youtube.com/watch?v=rbcGQI...eature=channel |
#30
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I love aluminum!
. . . . . . . when it is used correctly (yes, airplanes are perfect example), but I hate it when alu is used just because it looks clean/modern and when steel will do a much better job. You can also make steel look clean & modern. |
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