I have started, then later rejected, many ideas in building my latest homemade CNC machine - I am moving them to this post to clean up my build post and still keep track of the ideas I have tried...

I will list an explaination for why I rejected the ideas as well - Use "Next" or the index to the right to view the rejected ideas...

 


Rejected Because: Since I started my own Aluminum Foundry I just decided to not make any parts out of MDF...

Here's a look at the motor mount that I designed and cut with machine #1 :) You can see the six holes that will bolt the motor mount to the t-slot aluminum extrusion. Since I used the first homemade CNC machine to manufacture these - they are perfect! These particular mounts will hang off the bottom of the Y Axis - I will make two more of these (I think) for the X and Z axis. On the other side of the motor mount I will need two bearing mounts that hold the lead screw bearings.

Motor Mount Bearing Mounts Bearing Mount - Bearing Installed

 


Rejected Because: This Idea still showed racking and was just not tight enough...

I've decided not to use Angle aluminum for the linear rails of my homemade CNC machine this time - because it was proving just too difficult to attach it to the T-Slot... Basically the screw heads were getting in the way of the bearings... So I looked for something that would sit in the t-slot channel and I found some 1/2" galvanized pipe that fit fairly well and should give me a nice rail for the bearings to ride on... I might have to sand it smooth if it's rough - I'm not sure about that one yet - but here's a look at the rails and a preview of the base so far... Don't mind the 2X4 legs - they are temporary :)

Rails Base Preview

 


Rejected Because: I thought that adding an extra bearing I'd avoid the racking I was seeing with the homemade CNC Machine - I was wrong

Here's a shot of the four linear bearing trucks I made last night - came out pretty good... Basically I wanted to have room for 6 bearings so that's what determined the length of these (which is 100mm by the way) - the T-slot aluminum is 60mm so these hang over the edge by 20mm on each side... I'm figuring that's not going to be much problem - but we shall see... The next picture is the over all shot and then a close up of trucks installed, and finally a video of the gantry moving :)

Linear Bearing Trucks Gantry Preview Trucks Installed

Video of Gantry Moving

 


Rejected Because: This idea racked as well and really just took up too much space for it as well...

Well... I got the linear bearings installed and started working more on the gantry and they still rack :( even after adding another bearing from the original idea... So something is flawed with that idea... maybe it's because they're not exact - or maybe the idea just isn't totally good - I dunno... So... I started working on a new linear bearing idea! :) Basically I'm taking regular L-Brackets and rounding one side down with my grinder and installing two bearings two washers and the L-bracket make it just right to ride on the pipe - so far without racking :) Here's some pics of how that looks... basically I was trying to make my own V Bearings and I think these came out pretty good... if these don't work on the pipe like I hope, I know that a similar design will work really good on angle iron (with a point at the top) - but the pipe is already installed :) so I thought I'd give these a try... The last picture is a current look at the machine - I've got the motor mounts and linear screw mounts installed :)

New Linear Bearing Idea New Linear Bearing Idea New Linear Bearing Idea New Linear Bearing Idea New Linear Bearing Idea New Linear Bearing Idea New Linear Bearing IdeaCurrent Look

And here's a video of the gantry moving with these new bearings : Video

It seems a little tight and hard to move - but I think I can loosen that up a bit but I want to see if it loosens up with use...

 


Rejected Because: This idea was close - but in the end I decided that I didn't want the bearings to ride on the aluminum - I figured I'd get too much wear - and also the parts were made from MDF and I've decided against ANY MDF in this build... it was close though! :)

Ok - sorry to take so long between the last update and this one - but i wanted to really work out this linear bearing idea before I kept posting things that I eventually change :) so this update is (I hope) the last in this "Linear Bearing Idea" saga...

Needless to say - that last idea racked too :( so I started looking at solutions I could buy instead... But that's just not my style ;) hehe - so after searching through a bunch I came across a few that I could try to re-make for my purposes and here's the latest linear bearing idea...

Basically I used my first homemade CNC Machine to cut me some parts again - which means these are made from MDF (as that's about all I can get away with cutting on machine #1) but they should suffice until I can #1 make sure they are exactly what I want and #2 until I can use my second homemade CNC machine to make them from hard plastic (like Delrin) or aluminum... I might be able to machine Delrin (or the like) with my first homemade CNC machine - and I got a piece to try - so that update will be coming soon ;)

Without further ado - here's the pictures and videos of the latest (and hopefully the last) linear bearing idea!

Current Look Current Look Current Look Current Look Current Look Current Look

and here's a video of that Y-Axis moving HERE

Ok - so that seems to work really well and I've got ideas to stiffin it up if it does rack - but so far (after 100 or so slides back and forth trying to loosen it) it's not racking...

Next we have my idea for the X Axis and I'm not 100% sure on this one yet - it seems solid - but I'm not sure about having the trucks on the inside... I think I'll move them to the outside - anyway - here are some pics of it and a video :)

Current Look Current Look

Video of X-Axis Idea

 


Rejected Because: Previous Idea was expanded on, and I thought about making the MDF parts from aluminum - but decided against that because it's just going to be really difficult to get accurate results from my hobby foundry right now - and I've thought of another linear truck idea that so far looks like a keeper and is easy to assemble...

OK - been working on this linear truck idea for way too long - the last idea was pretty solid - but I've expanded on it a little bit connecting the two pieces with a piece of threaded rod rather than being two separate pieces - they act as one piece now... This makes it so that I don't need a piece of extruded aluminum right on top of the top piece and that gives me more table room :)

Also is a picture of the bed I put together that the sacrificial MDF will rest on... More updates coming tommorrw and make sure to keep an eye on the site as I will be posting about my NEW latest hobby very soon! ;)

Latest Linear Truck Current Look

 

 


Rejected Because: I think it will be too difficult to cast perfectly dimensioned parts in my hobby foundry - I just don't have the skill yet :)

It's been a long time since I've updated with any progress - I've been working on the Aluminum Foundry so I could cast parts for this project out of aluminum :) Finally I've had sucess with that and have made my first custom part ever :) To check THAT project out - go HERE

and here's a picture of the unfinished part straight out of the sand :) - it's not pretty - it has to still be machined - but I couldn't wait ;)

Z Axis

 


Rejected Because: MDF Parts...

Ok - Started working on the X Axis today as I think the Y Axis is pretty solid so far... Basically these X Axis trucks are wider than the Y Axis ones - basically running on the width of the extruded aluminum. I still kept the idea of bolting them together to keep it so it moves as one piece. I also bolted on what might be the beginning of the Z Axis - but I have to figure out it's linear motion so there's a good chance this idea will change... More than likely I will add an X Axis bar to stabilze the Z Axis as well which will really stabilize the X Axis too - we'll see :)

Without furthur ado - here's the pictures and one video :)

X Axis Truck X Axis Truck Start of Z Axis

Check out the video of the X and Y axis moving :) Click Here