excellent! just my .02

true, but the spiders could always be replaced with another material. They make them out of stiffer materials depending on the use.

Yes they do have a little play in them this is what I made and they have no play in them.

Joe you should add a 4th axis to yours so you can cut out gun stocks and stuff like that. ! Would be cool looking.

That is the next thing is an addon lathe on the cutting bed, My HobbyCNC Board is 4 axis now.

I just was not satified with my Z Axis so i redesigned it and I am now using skate bearings It is very smooth and easy to move compaired to the other one I had.

This has two 6" bearing slides and I managed to design it in such a way as to use U bolts and another bearing on the backside to keep it snug against the 3/4" Drill rod.

I am very happy with it now, and it has no racking in it at all that i can tell by trying to twist it by hand.

The travel is 6 3/4"

Joe

more

installed and with tool plate on.

That new Z axis is a great improvment from the old one i bet. Realy nice design.

Started Cutting the Bottom portion.

Joe,

what problems were you facing with the old Z axis set up? From what I can tell, your mod rotated the bearing angle irons 90deg and now require an additional bearing on the u-bolt to confine the system... Does this reduce the play much over the old system where the bearing angle irons alone confine the system? Is this new set up more adjustable or easier in some way? Thanks

-Rob

It makes it easier, and the additional bearing top and bottom on the rear ensures that all bearings are riding on the rail with equal pressure and locks it down to the rod, with the older system (if you are talking about my other machine) there can be slight movement, but works as you can see by me cutting all the parts for this machine on it.

Joe

Plus this new Z axis will not wear like the old one. I bet it will move smoother this way also.

Very smooth and with little force.

I sat down to update all my drawing files, and created several parts, motors, bearings, leadscrews etc. all except bolts and nuts. Wanted to make sure I keep up to date with them so it is not a chore later on.

Joe

another looking at rear of gantry

Hey Joe could you possably email me a copy of that torsion box article?

Sure i just sent you a message requesting e-mail address.

Joe

Finished cutting Large Y Axis and used the unit itself to make sure it is all lined up and leveled with itself, figured no better way that use the pipes themself. I used wax paper to protect the outer portions from woodglue to keep them removable.

just need to place outer skins.

I went to Lowes and got the Hitachi Router that (WarrenW from the zone) mentioned in his plog, this is the one.

http://www.lowes.com/lowes/lkn?acti...359-67702-M12VC

I made a mount and installed it on the New CNC and the Z axis has no problem lifting it.

lookin' good joe!

Well I took my other Machine apart and installed the new one, Very difficult job to do by yourself, trying to lift and hold at the same time.

Here are the tolerance just after I put it together with no adjustments whatsoever. I'm sure i could shim here and there to get it perfect if i needed to but for general cutting that is not bad at all.

Yeah or you could take the sacrificial deck out and use a flat bottom cutter to true up the tops of your ribs by making a pass over the whole assembly with the gantry.;-)

It is all glued together to make it stronger, so removal is not an option, but i could just skim the top cutting deck to true it up, but more than likely i will just leave it and skim the top of a 1/4" mdf i will place ontop to have as a replaceable cutting top.

Joe

Here it is so far i did not paint the bottom section i just needed to get it together, only thing left is to install the last end piece you see that this machine just cut out , I have spacers 3/4" thick at the motor mount to alow for it.

I also installed a quick router dust cover. You can see how much was left after cutting, not much at all the Cyclone even with just a small Shopvac got alot of it, I was very happy not having dust flying around. I cut the piece at 80ipm i can go faster but The 1/2"-10 lead screw started whipping a little i think it was bent slightly during shipping i can see it when i jog real slow.

Finished it up today, I added 4x4 post for legs and lowered off of sawhorses, It is pretty solid cutting surface is at 36" height. But I already have Ideas to start building it again and make it alot lighter. Look forward to Model 2006a (model 2007 was a mistake in typing....)

Looks great Joe. do any cutting with it yet? With this machine you could easily do some serious workworking. make some great looken cabinet doors and such.

wow! Looks like the Jgro on steroids!

(I'm building a shortened version of Jgro's "free router plans" unit) (from the zone)...but my little JapanServo steppers aren't quite up to the task - I got 5 tpi screws, but only 50 oz motors... (I'm definitely a NOOB)

i took it apart and it is sitting there waiting for someone to buy it... lol

The new one is beefy for sure.

well, I can't wait to start building a projector.. Don't have an idea yet which one.. I got into the CNC thing to carve out plaques from EPS foam, in which to cast into aluminum and brass. Mebbe I could cut "foamies" instead of MDF, and then cast aluminum parts for a dutier-heavier mill! Frank did it..
These aren't my pictures..they're simply gleaned off the net:
, and
and

To do something like that i would think you would half to mold and then grind. molds dont hold the tolerance to be able to use them as final parts. I work in a grinding shop. Its what we do. We mostly grind cnc routers bits and cutter heads for shapers. we also grind alot of Brazed on tools for manual lathes. the ones you find in Mccmaster Carr and MSC.

Joe's CNC Model 2006 R-2

OK Now here it goes, Seems like I'm never happy 100%, altho this machine is very solid and works really well I want to make it lighter without sacrificing its rigidness, The 200oz motors will cut at 80ipm but i do not want to go faster with them being afraid of loosing steps.

I have started to cut the new one using 1/2" MDF Instead of 3/4" for all the interior ribs and also Using 1/4" MDF for the Outer Skins of the Torsion Boxes, I can already tell this is going to be more than 1/4 the weight of the present one, I want to get the Drawings done and machine tested Before I send it to anyone, Hope you understand, If im not happy then i would not expect you to be either.

Joe

Here is the New Z Axis Carriage, It sure is alot of work to make things lighter by changing the thichkness, one thing changes another.

Anyway the new one weighs 9.5 lbs (old one 12.5 lbs) so you can start seeing how much weight is being shaved off.


Joe

Joe:
What is the speed of your cutting? IPM?, and what're you using, just a RotoZip? I'm cutting at only about 1 inch per minute, and with a RotoZip, and I gots serious burnage problems.. My CNC router only gets this fast (slow) , Due to the fact that the steppers stall badly at higher rate. They're little buggers, maybe only 25Oz and I gots 5 TPI leadscrews on the X and Y axes.. So my max speed is around 125 Hz (set on TCNC).

I built this rig to cut EPS foam for casting, even the spindle is too fast for that, cuz more than a 0.2" depth on Z results in serious meltage of the plastic, resulting in balling up on the mill itself

Gotta go.

Jefftt you are getting burnage problems due to your slow IPM. The rotozip has fairly high rpm's and your cutting to slow i bet.

Joe is using a Hitachi router I believe.

If you want I can look up the proper feedrates / rpm's for your router bits.

The spindal rate is to fast. On the router i use now I had to slow the RPM's down.

For the rotozip I made a router speed control switch here are the parts for about 15 dollars:
1. a ceiling fan motor variable speed switch (Not the light dimmer switch)
2. extention cord
3. Blue plastic wall socket box
4. and a light switch cover
this made a nifty little variable speed control.

I used a router speed control ( here ) from Harborfreight. Works great with my Dewalt, but it says it wont work with soft start motors. I believe you can still use it by starting it off at full speed then slowing it down after it gets going.

The switch is 3 position, variable - off - bypass ( full on)

I picked up one of these tile cutters yesterday. I have plans for it when I finish the house. It has a 12k 1.5 horse motor on it. I would like to try to adapt it to hold router bits. It only needs a Z and Y axis table.

EDIT: I checked the RPM and it's 3,550 not 12k. Need to think about this one.....

Wonder what it slides on?

Joe

It's actually slides pretty tight in the rail and may be able to be shimed as is. It looks like bearings on a teflon lined surface. I'm not willing to dismantle it yet..... my wife may suspect something is up. I figured doing the tile job myself pays for the saw anyway. Too bad it doesn't pay for the new knees I'll need ! If I remember correctly....It was like 3 months after the last tile job before I was without pain and that was 10yrs ago.

Slowing the rpm's down works also as they have stated. Another option is using less flutes on your router bits.

What kind of RPM's / Feedrate are you running yours Joe?

80ipm, 14,000-16,000 (calc from var. speed router), 1/4" carbide 2 flute endmill.

Thanks One thing also what bit are you using "Jefftt" ??

Joe

I'm feelin' yer pain, I just put down 300sqft of tile a month ago I started setting on my rump alot once the knees gave out

New Gantry side pieces, two 1/2" MDF Glued then will be bolted together.

80 IPM? I thought EIGHT was fast...
Joe..Right now..as of present.. I'm cutting EPS foam (Pink - Owens Corning, to be exact) and using little cheapy diamond encrusted nickel-plated mini bits (get a pack of 10 for 5 bucks)

But wood.., Just a 0.25" two fluted upcut flat mill..(Onsrud)

I did some fine milling with a 0.0612" upcut carbide mill (another cheapy from Harbor Freight) on Plywood, to do a 5X7 inch relief of Jesus, but didn't break any bits, but burned thru 6 of them!

I thought of the speed control, and that's a WAY easy solution.. but I want feed speed, and resolution. I know the spindle has to compensate for feed. I got my eyes on HobbyCNC's 200 Oz steppers.. just gotta see if my Stepperworld SP3/HT board will accommodate..

that stepperworld controllor says 1.25 Amp per Phase the hobby board and motors are 3a.

looks like I'll be getting the board, too, huh?

I have two hobbycnc boards and they work great.

At 18,000 RPM's you can run a 1/4" bit up to 300 IPM

Joe
The CNC looks like it coming along well. I am impressed with it. The quality and workmanship look great! Wish I had time to build one of these. How much do you have invested in the hardware for this?

I have not figured it out yet, I will be sitting down and paking a parts list with pricing for all the hardware, i have all the reciets.

Joe