Hi all,

I've attached a few pictures of my router. The first phase of building is complete. The grounded rods and the threaded rod for the X-axis have been mounted. I opted for the plan from Michael Walach (http://members.cox.net/walachcnc/plans.htm) .
It's a tabletop router with a moving table. It's supposed to be build from Delrin but I couldn't find any here so I opted for what I had lying around. I build subwoofer enclosures and have plenty of 10mm clear acrylic sheet. I converted all imperial units to metric (more or less) and designed my own linear bearings (which are in the process of being completed). I took the plexi to a local lumberyard and asked them to cut it for me. 30 minutes and 2 Euro's ($2.5USD) later (cheapo!) all my parts were cut to the millimeter. It took me three evenings to get this far. I've got 2 weeks of leave so that means plenty of time to spend in the shop! I'll keep the updates coming.

Greetzzz,

Dimitri

The results will be interesting, keep us updated!...isn't it rather difficult to drill acrylic without "crazing or chipping" it....

Not if you "modify" your drills. I use ordinary metal drills which I dulled a little. This prevents the drill from "grabbing". Also you've got to keep an eye on the drill speed. If you go too fast you'll melt a hole in stead of drilling one. I'm more worried if the acrylic can stand the forces applied to it when I'm going to route things on it. If it does, excellent, if it doesn't then this was an excellent way to refresh my machining skills. I'm off to the shop and will probably post the pictures of today's work later on.

Greetzzz,

RaiVeN

Would be great when it's completed. May be you can snap a lot of photos and some videos. Since it is transparent, you can see what's going where and how each component interacts. Good for CNC101 type FAQs.

Hi all,

Sorry for the delays but it has been hectic here. But I managed to spend some time in the shop. I finished the linear bearings for the X-axis and mounted the table onto the rails. It runs so smooth that it keeps drifting off to the left side because the stand it's on is not level. Nice!
I will finish the AB nut today and hopefully connect the stepper so I can shoot some videos of the X-axis moving. For now here are the obligatory progress pictures. Enjoy!

Dimitri

The results will be interesting, keep us updated!...isn't it rather difficult to drill acrylic without "crazing or chipping" it....

I spoke to a local plastics supplier yesterday and asked about the machinability of several different plastics. They suggested that cast acrylic will machine nicely, but extruded grade acrylic won't.

And last week, a rep from Garr tools visited me and suggested that I use a diamond coated end mill to cut acrylic and avoid melting. Actually, he was suggesting it for dry-cutting aluminum. But it aparently works very well for acrylic too.

By the way, Raiven, your project is looking very nice! The acrylic should look vey stylish when finished. =)

Thanks for the comments guys!
I managed to get the X-axis moving for the first time using turbocnc (3000hz at 1/2 step). I made a video of it but it won't upload (too large, have to find a way around this).
I noticed that the table has the tendency to "twist". After some pondering I noticed why: I mounted the linear bearings the wrong way around! I disassembled the entire table and started reassembling it again. I will test it tomorrow (no PC on site today) to see if the "twisting" is gone.

Dimitri

Hi everybody,

It's been a while since my last update but I managed to get some work done. Everybody wants a new sound system when it's summer. On the bright side this helps finance my router so it ain't all bad :D
I fixed the AB nut. It ran a little rough but after some work is running smooth.
While out of hex bolts one night, I made supports for the limit/home switches as a test. They came out pretty nice so I'm going to keep the design. I'll need to make 4 more for the Y and Z axis.
I finished the motor mount for the X-axis. I had to add some toothed rings (I don't know the correct english term) to keep the nuts from coming loose due to the motor's vibrations during slow moves.
And finally I completed the fixed gantry. The router is finally starting to look like the machines I see on the forum! There are 2 pictures of the gantry. One with the protective foil still on and one after I peeled it off (which took about an hour due to the foil being hardened by sunlight). I still need to align the rods but for that I first need the Y-axis basis. I am in the process of making the linear bearings. I opted for a different design this time. I took a close look at the table and noticed that it can flex a little when a large force is applied sideways. I figure that the weight of the Z-axis, the dremel and stress while cutting might be a bit too much. I took the design from jgro's plans (thanks by the way!), converted them to metric and modified them to fit my rod/bearing combo. They are coming along nicely but I forgot to take the camera with me to the shop today :-(
I attached some pictures of the work completed so far.

enjoy!

Dimitri

Interesting to see you using acyrlic, big fan of polycarbonate myself, have thought about building a another machine out of it, rather than aluminium as it is so nice to work with, plus I could cut the bits out on my other machine !.

It works!

I managed to finish the Y axis. It took some time to "dial" it in since I don't have the proper tools for that. I have been looking in the local stores but couldn't find one. Does anybody know where to get a dial online?
I hooked both the X and Y axis up to the hobbycnc controller. With a few pieces of acrylic and some glue clamps I managed to fix a pencil to the Y axis. I have to admit I got pretty nervous when I executed the first piece of g-code. My finger never left the escape button! :D
Even with one axis still missing and a simple piece of paper and a pencil the result was pretty nice. Only a pitty that the pencil was fixed and the line fades after a few centimeters. I've attached a picture of the setup and my first result. I can't wait to finish the z axis and cut my first part.

Dimitri

Congrats, Keep the pics coming and a video if you can.

Jason

Seen it, Love it, Wanna see final results

Vanger

Those linear shafts look "really" small.

I've been having problems uploading video's. Is there a maximum size? the file I have is about 4MB and shows the machine drawing the coca cola logo. I tried to upload but it doesn't work. :mad:

anoel: indeed, the shafts are small. They are only 10mm diameter. They were the only ones the store had in stock at that time. They are not as strong as I had hoped so I think I wont be able to do much more than milling PCB's on it and maybe some light engraving. I am going to start on the Z-axis now. See how far I can get this week. I would like to have the machine up and running by the end of the month.

Hey, i'm intrested in your acrylic machine, please post new picture! i know it's been a while... and the final results?

thanks for the compliment!

Unfortunatly I have halted the contruction of the router. The acrylic is just too "bendable" which results in poor accuracy. I originally wanted to route PCB's on it which requires a decent level of accuracy. In stead of pouring more money and time into something that won't work anyway, I've decided to stop working on this machine and am contemplating a new design (probably MDF and drawer slides).I've got time until the weather gets a bit warmer as my shop does not have heating and it can get pretty cold here in Belgium!

Thanks for all the support for everybody here on the forum but this is just one of those times where you have to cut your losses and move on.
But don't worry, I'll be back in the spring!

Dimitri

thanks for the compliment!

Unfortunatly I have halted the contruction of the router. The acrylic is just too "bendable" which results in poor accuracy. I originally wanted to route PCB's on it which requires a decent level of accuracy. In stead of pouring more money and time into something that won't work anyway, I've decided to stop working on this machine and am contemplating a new design (probably MDF and drawer slides).I've got time until the weather gets a bit warmer as my shop does not have heating and it can get pretty cold here in Belgium!

Thanks for all the support for everybody here on the forum but this is just one of those times where you have to cut your losses and move on.
But don't worry, I'll be back in the spring!

Dimitri
you should be able to strengthen it up by using 1/2" acrylic strips perpendicular to the gantry sides and where else needed you can use what is called acrylic weld a liquid applied with a dropper which welds the pieces together I have used it and you would break the acrylic befor the weld would break thats how strong it is.

Joe

The machine is not going to be scrapped! After some pondering I may have found a use for it. The Z axis was too heavy for this machine but if I replaced it with a pen I have a plotter! not wat I originally has in mind but it will work.
The only thing I need to figure out now is how to make a pen that I can lift off the paper electronically. I read somewhere on the web to use the coil from a relay. Any of you guys have a suggestion on how to build something like this?

Thnx,

Dimitri

Use a solenoid.

Look here (http://jameco.com/webapp/wcs/stores/servlet/CategoryDisplay?langId=-1&storeId=10001&catalogId=10001&categoryId=352010&productId=100352010&sitemIds=%28142463%2C+145314%2C+149753%2C+149761%2C+163803%2C+169834%2C+215141%2C+262166%2C+262174%2C+262182%2C+262191%2C+262203%2C+262211%2C+262220%2C+262238%2C+262246%2C+262254%2C+262262%2C+262271%2C+262289%2C+262297%29&f1=687%7CTubular-push&f1=688%7C24&action=Reset+Filter)

just thought I would wiegh in here, as this is my design..sort of.

Plans call for 3/4" HDPE not plexi. The hdpe is WAAAYYYY stronger and doesn't flex like the plexi. Not a bad looking machine, but you need stronger material. HDPE is also very easy to cut and drill.

www.bigbearcnc.com