Another Banana Bender's Build !!!

[epineh]

Chich has been doing some fine tuning to the Z axis and it is really starting to look the part, should be pretty sweet once it is all up and running.

I am saving for a spindle now so things will be quiet for a while, once I have it the toolchanger build can start, several drawings have been done in chalk and at least two beers have been drunk so that takes care of the planning stage

The design has changed a little, in that I am going to make this a cantilevered gantry, I have a couple of reaons for this, the main two are simplicity of building and ease of job loading, with no side gantry slide at the front it is all nice and unobstructed.

It will look a bit weird but hopefully it goes to plan and works for my needs.

Russell.

[epineh]

Well time to brush the cobwebs off this build, I have received my spindle today, 0.8 KW air cooled with er11 collet, I already have a VFD for this, 1.1 KW so I have a tiny bit up my sleeve so hopefully I can get reasonable spool up times, not the end of the world but always nice to push things along.

I have a friend with a really big VMC who has kindly offered to cut out the pieces for the router for me out of 16mm plate aluminium, I have purchased about half a sheet and hopefully that should be enough to make the whole machine.

Bed size is still a respectable 400 by 800 and will consist of a solid sheet of 16mm plate ally with a grid pattern drilled and tapped for job clamping (probably 6mm), and also I am going to try Rod's method of cross clamping as I am doing something similiar with my first machine, though not as pretty looking as Rods setup

Still unsure of the servo drives, at this stage I am going MESA 7i43 anything IO card with "Dumb" H Bridges with EMC closing the loop to the PC, this is a little daunting for me but I hope to plod along and give it a go.

Plan B is to build standard step/dir servo drives and I was always going to try build a version of the DSPIC servo drive, it originally used an obsolete op amp for the power stage but now has a standard PWM output to drive discrete power stages and works very well by all reports.

Unfortunately I have decided to put a hold on the toolchanger until the machine is finished, I will still have a go at it but for now the rest of the machine will take priority, besides I am thinking of starting from scratch rather than adapting an existing spindle which should give me a few advantages.

Enough of my ranting, I will post some pic's once I have some plate aluminium cut out.

Cheers.

Russell.

[chich2]

Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? Is it Made Yet? .......................... How about NOW???? ................. Now maybe?????
Can't wait to see your build Russ. It's going to be a sweet machine!

Chich

[epineh]

Lol Chich, no not yet

At least I am back on my feet after being crook for a few weeks, not quite 100 percent but almost !

I am tempted to try machine the Z axis servo mounting plate with my old router, never did try cutting aluminium with it, would be interesting to see how it goes, sounds like a good weekend project.

Cheers.

Russell.

[epineh]

Alrighty...some pics

The bed is done, 50mm grid spacing drilled and ready to tap, my mate had a little trouble with the rigid tapping (broke one tap) so he started the thread and left it at about 5mm deep and I will get busy with the battery drill tonight and finish it off. (8mm thread)

The whole thing is straight off the VMC so it all needs a little cleaning up. The second lot of parts make up the base for the machine, 5 of in total, they sit on the bottom, and the bed, X axis linear rail base's slot in, the bed then bolts to the base pieces and should all be nice and rigid.

The aluminium is all 16mm thick, as mentioned the bed is 800mm by 400mm. With a bit of luck the bed can be converted to a vacuum table eventually if required, otherwise I will just make a small jig with vacuum for milling PCB's, about the only need I have for a vacuum table (for now anyway )

Once I clean things up I will sit the pieces together and post more pics which will make things a little clearer. It is a cantilever design so it might look a little strange for a while (maybe forever, lol).

I put the spindle in one pic for interest sake.

Cheers.

Russell.

[chich2]

W O W!!!!! Looks awesome already!!!!! And doesn't even look like a router yet!

Chich

[Rodm1954]

Looking great Russell.
16mm plate will make it strong as. It is good to have your parts made on a CNC machine.
Is it finished yet? Sorry couldn't help myself.

[epineh]

Originally Posted by chich2 W O W!!!!! Looks awesome already!!!!! And doesn't even look like a router yet! Chich

Thanks Chich, hopefully soon it will start looking like one

Originally Posted by Rodm1954 Looking great Russell. 16mm plate will make it strong as. It is good to have your parts made on a CNC machine. Is it finished yet? Sorry couldn't help myself.

Cheers Rod, I think (hope) it should be rigid enough and yeah it is nice to watch a big machine cutting out parts for a router !

Lol you guys are sounding more and more like my kids...are we there yet ???

The last machine took a couple of years and then some to make so don't hold your breath, though I have learned a thing or two in the process, and I have all the parts now ready to assemble more or less apart from the rest of the plate to be machined so you never know

Oh yeah there is going to be provision for a lathe headstock/4th axis that will literally bolt on to the end of the bed, plans at this stage are for a large servo to drive the spindle, something along the lines of a C40 generator/starter converted to a servo, with a bit of luck and research power should be between 1 and 2 KWatt.

The design would probably be able to use some kind of gang tooling but a quickchange toolpost is probably the most likely option for now. Should make for some interesting video's if it doesn't catch fire.

Enough pie in the sky...better get back to it...

Cheers.

Russell.

[neilw20]

Don't forget to add a temperature sensor, so that Mach3 (scaling) can automatically compensate for the hot weather you get up there.
LM35 is perfect. 10mv/deg C. That will be some accurate machine, as well as pretty.

[epineh]

Hi Neil, nah it isn't hot up here...middle of winter and it is a balmy 25 deg, may go for a swim later

Bedsides, you guys would probably need temp compensation to stop ice buildup

Hope all goes well for you guys at the BBQ, I expect to see lots of pictures !

Cheers.

Russell.

[epineh]

More pics, I cleaned up the pieces and tried them for fit, so far so good, the bed will sit a little lower as I need to chamfer the bed to fit in the rounded part of the base pieces but you get the idea.

Next is to mark and drill the base pieces ready for bolting together, also chamfer the bed then it is onto making the linear rail bases and clamps, you can see the slots on the end of the 5 base pieces, this is where the linear rail bases will slot in, as with everything else they will be made from 16mm plate.

Cheers.

Russell.

[Rodm1954]

Hi Russell,
I couldn't work out how your base supports fitted but it is clear as mud now. Will the area between the table and rails be where the tooling will sit?