Thanks Ken,
thats great, It looks just like that, only problem was I turned it around and the bolts fell out ;-)
If you coloured bits different colours it loses it in .sat
do you want to do the rest of it?
la_coterie,
I also found that .sat does not maintain original colors or layers when importing, same thing with .stp, as the different components were different colors. It seems to import to the same color that is active.
I will have to pass on doing the rest of it as a commitment although as you/if you post parts I will see what time permits in converting them to 3D solids/surfaces.
Maybe this will encourage you to get your feet wet in solids/surfaces.
Ken
I like it and I want to ad that it is possible to cheat a little more. E.g. you can make the table let’s say 300 mm, keep the rod just above 600 and put a support in the middle under the rod. By letting the table have one cluster of bearings on either side of the support you will increase the stiffness dramatically (I guess 4 to eight times). Anyway, the thicker the better.
Another cheat is to only use a thick, circular rod like the one in your picture on one side of the frame (table or whatever), letting it guide the direction and on the other side of the frame just use a flat iron standing on the edge. A simple ball bearing carriage (ball bearings above and under the flat iron) is all it takes on that side to keep the direction and you get around the problem with keeping two circular guides exactly parallel and you save time and money as well.
/jan
(Sorry about all bad typing in English. It isn't my native lingo, I just do the best I can.)
la_coterie that skate-o-rail looks very interesting concept
Like alot of other people in here im constantly searching for a DIY table where i can make all the stuff myself , rather than just purchasing expensive industrial linear bearings.
will defantly consider this setup for my plasma table
cheers
la_coterie....Very nice design!!! Thanks for sharing it.
I myself am kinda new here and have been lurking for awhile. I've looked at different designs and found a few that I liked and this I really like. K.I.S.S
Anyway, I may be way off here but I can't help but think that it might work better to flip it upside down and have the 2 bottom bearings at the top (at roughly 11:00 and 1:00 or 80 degrees apart) without elongated holes.....meaning that they would be fixed. Then put the single bearing that was originally at the top, on the bottom now (6:00) with elongated holes to allow for adjustment. My reasoning is that by having 2 fixed points at the top, you're creating a "V" that will allow the pipe to automatically center itself on both sets. Then you just tighten the bottom bearing up against the underside of the pipe and that's it. I just think that 2 adjustment points allow more room for error. I've added a .dwg file to show what I mean...
I'm thinking that this might cause some stress to the part by having a "wedging" effect but by closing the angle to maybe 70 degrees this could possibly be avoided???
I'm no engineer so I can't say for sure, but that's my 2 cents. Anyone with an opinion please let me know what you think....
Originally Posted by Steve_01
That is basically what i did here on my Z Axis, and it locks it to the rail very well.
http://cnczone.com/forums/showpost.p...&postcount=207
Joe
hi
I'm still searching on the world wide web , and come across this website seems alot of good bearings for CNC made machines
link www.vxb.com i went to there linear bearings section http://www.vxb.com/page/bearings/CTGY/LM
have a look guys see what u think
cheers
hi
have a look at this CNC Bushing 25mm Linear Bearings Aluminium Pillow Block
http://www.vxb.com/page/bearings/PRO...ystems/Kit7270
Code: Kit7270
Price:$39.95 not a bad price if u ask me
Chrome Plated Linear Shaft 60" (5 feet) Long 25mm Diameter Hardened Rod
http://www.vxb.com/page/bearings/PRO...ystems/Kit7198
Code: Kit7198
Price:$79.95 again not a bad price
cheers
Looks nice -
I would like to use something similar to that for my rails....
Please check out my CNC blog
http://cncinside.com
How long does it take to chain drill this on a windy handle mill compared to the cnc mill you spent your money on? and hows the patent application going? could the same effect be achieved with 3 bearings? thus slimming down the patent application?Hi All,
I've been lurking and talking onboard bits of various designs, In particular
http://www.terry-is.f2s.com/future/l...g/linearb.html
although I've used the generic design some years previous.
This uses 60 x 8mm and 25 x 10 for the bearing holders, the bearings being 19 x 7 x 6 shielded. You'll probably notice that its in steel, I guess it would work as well in aluminium and be much quicker to machine.
Do you know how long it takes to chain drill that lot? I don't I've a cnc mill lurking in the corner of the barnThere's no reason why you couldn't do it with a windy handle mill (manual) if the sole objective is to save money. Well I have to save money I've spent it on a cnc mill
Keith
Hi. I was surprised to see a link to my website at the start of this thread. I was intending to make some prototype bearings of that type, but never got around to it. I posted that rendered CAD drawing on this forum quite a while back to get some feedback and try and improve on it. As I remember there was not that much interest. Looks like things have changed though, and I'm glad somebody has taken the idea and tried to make something of it. I know what you've made is not exactly the same, but if my CAD rendering inspired you to make what you have, then I'm very happy. I really hope it works out.
Wow I just dug out the old thread. Over 1.5 years old now......
Here's the link...
http://www.cnczone.com/forums/showth...highlight=idea
Best Regards Terry.
Hi All
Sorry I've not been very active in my thread, I'll try to answer some of the posts.
Steve_01 I think your idea would be very good for a Plasma table. My logic is as follows, with a plasma table the weight of the gantry is always downwards, with a router table the weight is being lifted when in cutting mode, so that's why I designed it with 2 bearings underneath. On a small hobby router I can't see that in practice it would actually make much difference.
I've drawn a revised version for those wanting to put a table on top of the rails rather than at the side, see attached.
Kipper, I'm not sure if you're talking tounge in cheek or not. Anyway I think it could be done on a manual mill with a rotary table, after all you're making 16 or maybe 24 of the side plates..
MrBean thanks for giving me the light bulb moment and linking what a project I'd already done with this one. I'd been searching the web for design ideas (cribs) but to me many had seemed rather complicated to what should be a simple thing. I guess it depends what equipment you have available, after all with only a drill and a hacksaw my design is damn near impossible!
I've moved on a little, I have parts of the gantry assembled, but being loathed to spend money I lack the rails, I'll post a photo soon.
Here's some photos, of the gantry, not finished, there are some stiffening rails to add and the brackets for the motor and gearing to add, and of course the rails, and the table - heck there's a lot to do still...
Here we are, avid reader(s)
I've moved on a bit, got some rails now, well actually stainless steel and triangulated the support beam as it has to hold a 18kg motor!
As best I can tell with a dti sitting on the floor and putting my weight on it I seem to have about 0.002" deflection, at which point I thought f**k it that will do
Once the guide rails were aligned, which wasn't too difficult having a fairly large mill table to rest it on, it was relatively easy to adjust the skates to roll without play, the best way was to tighten the blocks loosely (if that makes sense?) and tap with a nylon hammer.
After all the designing & machining it's good to actually be able to "play" with a real one instead of a computer generated one. In fact when I go in the workshop I feel a compulsion to move the chariot along its axis
It will propel itself along with belts & servo but next will probably be the table as I have the material for that & I keep modding the belt drive system. Once I start making the drive train bits I won't change it as it only leads to errors
Do you have picture of the bearings from the abouther side?
I'll take one over xmas.
belt drive works a treat!
Cool, I am truying to make my machine based on your berings so if you could take pictures og moutings and how you solved a Z axis and please take pictures of your belt drive solution.
Very interesting..
One thing I can say. The bearings are asome....
Here we are a xmas treat, now as this progresses I'm not sure if I should start a new thread in build logs, whats the view?
A few shots of progress so far, the Y drive belt system which under power using a servo seems very good and fast though rather dangerous at the moment because it's just powered by a battery rather than computer so doesn't stop quick! and has a good chance of crashing into the ends
For the technical minded its on a 12.25 reduction with a 28Tooth pulley on final drive, 5mm pitch which according to my spreadsheet with a 1000ppr encoder will give over 17metres/min in Mach3 at 25khz mode or to be really crazy at 45khz mode nearly 31metres/min holy cow!
The Z axis is almost conventional with linear rails and a ball screw, I considered that this was probably the best way to go as it can be kept more compact and hence the Z will remain close to the Y minimising any twisting action.
As an aside, here's a party piece for the season, take a linear rail and take a carriage off the rail allowing the beaings to drop on the floor, preferably a tiled one, you won't believe how for those balls travelIt can also be used for an ice breaker at a meeting. (I acceppt no responibility for the bearing that remain missing
Asome!
Nice xmas pictures
How big are yout servo? (torque)
I am planning to use 1160oz-in stepmotor on y and Z axis and 2 of them to drive gentry...
I hope it will be enough
urmm, don't know! I think it's a bit of overkill (too big) but the price was right it's about 100mm diameter and 200mm long.How big are yout servo? (torque)
Don't forget your torque gets multiplied my the reduction gearing at the expense of speed, so I could probably pull lorries out of the snow with this setup
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