[Sheridan Basses]

Thanks Ahren. I loosened the bearing block and pulled it back towards the motor with a clamp them retightened. Looks as though the coupler was rubbing on the brace. Hopefully that did the trick. Kicked up the velocity on the axis in Configs to really push it hard and it appears to be much smoother. Maybe that would explain why I was getting ovals instead of circles on some test cuts. Going to start fine tuning to remove any backlash, etc.

Did I mention that the R&P drives rip? Very fast. Starting to get real excited now. Thanks!!!

[rfeatherhawk]

Randy

Sorry -- I'll get this cleared up right away if I still owe you something. You were building a modified Joe's machine if I remember, so the new spring tension system doesn't work. I thought I sent you springs and turnbuckles, but if I overlooked this, I'm very sorry and will get some out to you right away.

Ahren
www.cncrouterparts.com

Thanks for the help Ahren.

[rfeatherhawk]

The R&P system is based on a pinion with a 1" pitch circle. The total linear distance traveled per revolution of the pinion is thus 3.14159". With the 3:1 reduction, this means that the distance traveled per motor revolution is 3.14159 / 3, or 1.0472". If you have a stepper with 200 steps per revolution, this means you have 200 / 1.0472" = 190.9861 steps per inch, or 0.005236" per step. With 10x microstepping (like in the G540), you would have 1909.861 steps per inch, or 0.0005236" per step.

Ahren
www.cncrouterparts.com

I'm using the Gecko 203V drive and can I assume that this formula will be the same for them?

Thanks

[ahren]

Randy,

The Nema 34 system has a 2:1 reduction instead of the 3:1 on the Nema 23 system. Most Nema 34 motors have plenty of low-end torque, so it is geared for greater speed. The rest of the equation still applies, so the distance travelled per rev is now 1.5708". 200 / 1.5708 = 127.32 steps per inch, and with the G203V's 10x microstepping, this comes out to 1273.2 pulses per inch -- that's what goes in the Mach 3 motor tuning page.

Ahren
www.cncrouterparts.com

[rfeatherhawk]

Ahren,

That sounds Great. It slipped my mind that the nema 34 R&P has a 2:1 reduction. Looking forward to getting this up and running. I'll try to post a video when the time comes. (Soon I hope.)

Thanks,

Randy

[rfeatherhawk]

Randy

Sorry -- I'll get this cleared up right away if I still owe you something. You were building a modified Joe's machine if I remember, so the new spring tension system doesn't work. I thought I sent you springs and turnbuckles, but if I overlooked this, I'm very sorry and will get some out to you right away.

Ahren
www.cncrouterparts.com

Ahren,
The parts made it here today. Thanks

If these turn out to work ok, do you want the other springs and turnbuckles?

Randy

[P.Passuello]

Hi Ahren,

What do your recommend to use as lubrication on the rack and pinion?
I am concerned if I don't lubricate it will wear and if I do it will attract all the dust in creation.

Cheers
Peter

[DanOSB]

if you lubricate it with some kind of oil it will attract dust and make it stay there.. not coming off.. its better to leave it dry.. make sure no oil or anytihng on it.. and blow air every now then.. that would be my suggestion.. keep the teeth down instead of up so the dust wont build up on teeth..

[rfeatherhawk]

What about a dry lubricant? I would think that some lube would be better than none like liquid wrench or equivalent. Just a thought.

[freecncplans]

I spray WD40 on my racks and pinions once a day. It gets dust all over it, but the teeth push it out with no issues. This machine has ran for several months and we run it everyday for 5 or 6 hours a day. Sawdust is not an issue, metal shavings may be another story though.
Sean

[Tartan5]

I see most people are using the R&P systems on wood routing systems. Does anyone have any idea of the repeatability and accuracy of these, and would it be ok for a unit that mills aluminium?

Thanks!

[oldhack]

I see most people are using the R&P systems on wood routing systems. Does anyone have any idea of the repeatability and accuracy of these, and would it be ok for a unit that mills aluminium?

Thanks!

Ive done mostly wood, but i have tried aluminum and plastic and corian. Works fine for all of those. If youre using a 3 1/2 hp router then you can cut a little deeper with each pass. I use a 2 1/4 hp Makita router and cut out some 1/4 aluminum with no problem at all. I only did 1/8 passes and lots of WD40. At work they use a solution that they make to do the same thing. The accuracy is what you make it if you build your own machine. The store bought ones are just as good. I think its better than the screw system, but thats my opinion. My answer is .... Get one.

[jsheerin]

How do you cut corian? Does it take different bits and do you use coolant? I'm interested in that for a future project.

Thanks,
John

[solodex2151]

I see most people are using the R&P systems on wood routing systems. Does anyone have any idea of the repeatability and accuracy of these, and would it be ok for a unit that mills aluminium?

Thanks!

It all depends on what system you mount the pinion units too. I have noticed on my 2x4 prototypes that you can achieve < 0.005" accuracy if you run in the system properly. Haven't tested repeatability, but I would imagine it would be with .007" per foot.

Regards,

Nate

[adam_m]

How do you cut corian? Does it take different bits and do you use coolant? I'm interested in that for a future project.

Thanks,
John

Corian mills up just like lumber... and uses wood tools - no coolant needed.

Adam,

[jsheerin]

Thanks. I had no idea.

[adam_m]

I can't wait to see what your going to mill up... I like some of your past projects, nice work!

How's the new machine coming along?

Adam,

[jsheerin]

No real progress - I'm packing for a move. Pics of the project I'm currently finishing up are here:
http://ldsg.snippets.org/HORNS/images/090925_Goto_BLH/

[Drools]

Is making speakers part of your business? There are some interesting looking speakers there!
Good work!

[Bear5k]

Alrighty all, I finally have some pictures of the Nema 34 systems to show you. I haven't had time to set up video yet -- business has been through the roof in March, and I want to use a G201X and a 960 oz-in stepper before I shoot it, but at least here are some decent shots. The system comes with a unique tensioning system that works really well (if I do say so myself ), and is even easier to adjust than previous spring and turnbuckle system on the Nema 23. The spring and turnbuckle will still be available for those not using my carriages, such as Joe's users. Pictures below. The first run will likely sell out this week, but I'm working on getting more in the pipeline ASAP.

Best regards,

Ahren
www.cncrouterparts.com

Ahren - I know these are for the NEMA 34 motors, but it triggers a question on the NEMA 23 mounts:
a) Any chance to update the NEMA 23 mounting system? and
b) Is there any chance of offering multiple reduction gears? A 3:1 reduction gives this a similar theoretical resolution as a 1 TPI screw. I'd love to get a bit more if there is room (doesn't really look like I can get all the way to a 6:1 in the pictures). I just don't need 1000IPM jogs if I'm only going to cut at 200ipm - 250ipm (predominantly thick Baltic Birch plywood).

Also, count me in with the group who'd like some more concrete numbers on backlash. Lots of great reports, but anecdotes aren't yet data without a fair bit of methodology and consistency behind the measurements.

Thanks!