Hello from Sunnyvale, California

[kb18951452]

Been kinda thinking here and there on MechMates for 2 years or so. This is my first time to log in wince Feb. 2009, (right before i moved to California).

I currently have a JoeCNC 4x8 Hybrid. Been considering some changes to is, and a friend of mine said "Soon or later is going to make more sense to just build a mechmate." And i must admit, He's right. For the kinds of things i wnat to do, a Mechmate is right of my ally.

I am capable ofwelding (Not very good Yet) And since i already have all the electronics needed for a mechmate (Steppers 3@900oz 1@600oz), And all the accompanieing electronics and software, A Mechmate seems like it might be a pretty good idea. My current machine has some issues i am still working thru (well lets be honest i jsut learned how to baby the thing past the problems, instead of just fixing them).

So, Thought i might get on here, see if i could get some ideas together, maybe start contemplating how much i might need to build one of these things.

I already have the electronics, I think my main project would be the base, and the gantry.

[gmcclure]

Welcome Ken, nice Blog on your web site

[MetalHead]

Glad to see you have a MechMate in your future !!

[domino11]

Welcome!

[kb18951452]

Been a while.

Want to start feeling out and gathering information for a specific build for my purposes.

I have an existing CNC, it has a rail systems similar to that of the mechmate (as in, i have v rails). I deal with twist, and deflection. The sources are numerous, and sintead of trying to stiffen what i got, i thought i might just build the mechmate gantry/carriage assemblies, and put them on my current machine. it would eliminate all the part that are causing the problems on my current machine.

So, If i could get a bit of help form the community, I'de appreciate it much.
I was looking over a sketchup model listen somewhere on here.

I don't know which is which, but i am going to say that the X is the Gantry, meaning the carriage riding on the gantry moves in the X. So, on that carriage is it a motor w/ rack and pinion on e one side, and just a wheel on the other? in other words there are 4 motors on the typical router mechmate? 2 to move the gantry, 1 for the carriage, and 1 for the Z?

Secondly, incase this has already been done, or if someone knows allready, how would i identify all the parts that are needed for the gantry, carriage, and z slide?

Thirdly, I read that some say to just have a machien shop make some of the parts and other say certain parts are easier to do yourself. I have access to a plastma cutter, and bending tools, And welders, actually, just about every metal working machine tyou can imagine, Are there some parts that will just be easier to buy from someplace as opposed to having them made, or trying to amke them myself?

Thanks ahead for all the help. I really like the mechmate design, and hope to have atleast half of one in my shop

[bradm]

Ken- (is that right?)

The X direction is the gantry itself. The "Y car" or carriage moves along the X gantry and supports the Z. There are four motors on a typical MM as you've identified.

You should consider starting from the standard laser cut parts kit, as the only pieces in that kit that aren't part of the gantry, carriage, or Z are the cable chain supports for the X axis, and you'll probably need them as well. Go See metalhead's store.

[kb18951452]

Kenneth, and thanks for the reply. Right now i have a n 8 ft gantry. I want to keep that, if i can. To reduce theamount of money spent on the conversions. Of course, by the time i am done with this, i am probably going to have allot of money tied into this.

I printed the plans out today, put them in a binder. Seems like i need to look over the plans, and check out everything that is under pages 10 20, 10 30, 10 40 sections specifically. Anyone have a grinder skate i can borrow? Seems something people would only be using one.

I'm beginning to read over the plans, there is allot here. Gonna take some work to get this done.

[bradm]

I see why you are thinking of X and Y differently; MechMates generally have a gantry that spans the short dimension of the table; looks like Joe's 4x8 hybrids are the
other way around, according to a quick look at cnczone.

It looks like a single alu beam gantry design spanning the 8 feet? Not to dissuade you, but perhaps you can describe what improvements you expect from a MechMate hybrid? I'm a bit concerned that you won't get the fixes you're looking for unless you build a MechMate gantry; in fact, I would argue that most of the MechMate magic is in the gantry and car design, both of which have wide, stiff, stable footprints.

If you are going to build a Mechmate gantry, then the kit above will include what you need, including the skate. If you aren't, then you'll need somebody's skate if you want to make rails.

Have some fun perusing the plans, and let us know what your thoughts are.

[smreish]

Kenneth,
I little insight...I didn't purchase a skate or have it laser cut....I made it.
In the early days when no skate existed, Gerald and the early adopters worked out a design.
I printed the final design on paper, spray adhesived it to steel plate, and made it by hand. A few holes drilled, a cutting wheel and a hole saw and I was done. The 45 degree angle was done by cutting out both parts of the "bent" top and welded them on the fold line. If you can't track down one here....it only took me about 4 hours to fabricate.

http://www.mechmate.com/forums/showt...0&postcount=12 THis is the detail of how it was done.

Good luck.

Sean

[MetalHead]

I sell just the skate and one also comes in the basic laser cut parts kit. Which you need the BLP kit anyway to build the gantry conversion.

http://www.cvsupply.com/servlet/the-MechMate/Categories

[kb18951452]

Mike, you are harder to find than a whiskey bottle in a preachers house. I have called several time but i just can't get you on the phone. My email is kennethscottbarry@gmail.com. I was hoping to get someone on the phone, ask a few quick questions, to get me going.

I think i am confused right off by all the different prints in the plans for what appear to be the same part. Seems there are 5 different "x rails" assemblies.
I think i Am going to need to do a bit of customizing to what i have now to get a mechmate gantry car. I believe thats where allot of the stability comes from. If i could do it with what i have, that would we awesome. I see people are doing long gantries.

I thought that starting with the longer gantry would be a good way to begin. My machine would take the fewest adjustments currnetly, to stick with the long gantry. Secondly, if i turn my gantry, i don't think my base table is long enough to, with the car, have 8 feet of cutting area, but i might be wrong.

[MetalHead]

Well shoot you must not be in a Baptist Preachers house !!! I sent you a PM. Work (real job) has been real busy the last few months eating up all of my time. Gotta do what pays the bills ya know !!!

[bradm]

Kenneth, if you take a closer look at the drawing designations (see the "reading the drawings page" which is about the seventh or so), you'll see that some are assembly diagrams, some are weldments, some are drill, and some are clearly marked as optional.

There is no problem with having a long gantry, but the width of the gantry may reduce your working area; you'll need a 6' table to have a 4' cutting area. With a "short" 6' gantry, a table to cut 4x8 sheets will be 6x10 feet; with a "long" 10' gantry, the table will still be 6x10 feet.

Both the gantry and the Y car are steel weldments for a MechMate. Is your current gantry steel? Is it a single bar, or a double bar?

[MetalHead]

Post some pics of your current setup and we can give you some ideas.

[kb18951452]

I'll get some pictures together of what i have right now. Have to look for them. Its 80/20 aluminum beam, with 1/8" steel plate bolted to one side of it (because the al. beam is a 6 footer and a 4 footer spliced together.

I think my table is 108" by 72". The nice thing is, I think i have enough tubing (it's all bolted together), to make a proper base. I might find someone to buy the al. 80/20 off me, to pay for the ubeams, and other metal i lack for the upgrade.

Question,
Looks like i need $500 for the BLP (Basic Laser-cut Parts), I have all my electronics already, and all the metal i need for the base table, except for my u-beam rail supports and software, and computer (remember i have a working machine),
Beside that, anyone venture a guess at the budget i will need for the rest?
That would be, general guess for fasteners, rails (hope to grind my own), Non lasercut parts, and however the zslide is done (i was thinking of getting one of those nice k2cnc ones, are they compatable with the current design?)

I am guessing that i need <$1000 Anyone venture a guess I don't even know how i will do this. Since my current machine is in use, and take up my entre shop (with room to walk around it)

[bradm]

Okay, let's make some assumptions: You are going to try to reuse existing table components which are 80/20 alu. You will make a new 108" MM gantry, car, and rails. You will bolt the C channel beams onto your existing table somehow, and sort out and stiffness issues. Your working area will be 72" - 24" = 48" by 108" - 18" = 90" (short of 8').

Also, note that I am not a mechanical engineer, and I'm about to shoot from the hip here:

You'll need two 72" pieces of 6" C Channel, two 108" pieces of 4"x2" tube, two 72" and two 108" pieces of 2" x 2 1/2" angle. Also the plate and stiffener for the Z Slide. I think you're into the $600 range for this steel as a guesstimate.

Then, you need rack if you don't already have it, and pinion gears. You'll probably want MetalHead's machined parts kit unless you have a lathe. You need the vee wheels and bearings.

I think you should budget with contingencies at closer to $2000, and then see how much you can beat it by. If you eventually decide to upgrade to an all steel table, another $600 or so.

[kb18951452]

i have an all steel table already, minus the rail supports being 2x4 aluminum extrusions.

I have rack and pinion also, so it will be reused. I don't know if i need to replace the aluminum or not, maybe , maybe, maybe not. I certainly see the benifits of having stiffer material for the verticals.

I could, however, just weld up my current (bolted) table, then drop the u beams ontop (and let them overhang to give m e the length needed, . So, smaller base, but normal sized ubeams on up.

[Gerald D]

http://www.cnczone.com/forums/944859-post16.html