[j2sip]

Hi, newbie here..

I tried emailing Dave Rigotti (using [email protected]) three times and a failure delivery notice is sent to me everytime. What gives?

I'm still planning to buy his PRO kit.

Thanks

Jordan

PS
Is there another email address of Dave out there? Pls help.

[strond]

I am in the same boat as you. I also want to buy the PRO kit but all the emails I sent him got rejected.

[j2sip]

This http://www.piclist.com/techref/io/st...m/SLAm_bld.htm seems more attractive although the commonly available stepper for it is the one from hobbyCNC. Oh well.. I hope somebody offer us alternate choices for both motor and drives (no Geckos pls). BTW my router is a 3ft X 2t affair with 30"x18" cutting area.

[diyengineer]

http://www.kelinginc.net/
Steppers and servos, drivers and everything else.

cnc4pc.com
breakout boards, relays, the works.


Just a few options.

I purchased and soldered a 4 axis hobby cnc pc board together a year ago and worked well but sold it for bigger and better right away. Good board on a super tight budget though.

I bought gear reduction and my servos through keling, and everything else through cnc4pc. Both are awesome people. I purchased Viper drives though, they do no make stepper drives.

[j2sip]

Finally!

Thanks, diyengineer. It seems Dave is busy, with another drive design perhaps? The keling 425oz-in or the 282 oz-in is what I'm eyeing at the moment. I understand that I will not be getting the full power of the motor if I use unipolar driver. Knowing that, my CNC will have a 1:4 drive reduction. Do you think it will have enough force to mill wood? and perhaps aluminum?

[diyengineer]

Do you have a picture of your machine? how much does each axis weigh that the stepper must move? What kind of maximum Inches per minute do you want? What do you plan on machining metals or woods or both? Load up some pics!

Finally!

Thanks, diyengineer. It seems Dave is busy, with another drive design perhaps? The keling 425oz-in or the 282 oz-in is what I'm eyeing at the moment. I understand that I will not be getting the full power of the motor if I use unipolar driver. Knowing that, my CNC will have a 1:4 drive reduction. Do you think it will have enough force to mill wood? and perhaps aluminum?

[j2sip]

The machine is still in its design stage. It uses homemade V-bearings
[IMGhttp://i49.photobucket.com/albums/f251/j2sip/1.jpg[/IMG]


A "ghosted" version showing redution drive and chains.




Which leads me to another question. Will the 4 V-Bearing hold the table in place? There will be no preload as such, the table is being held only by the force of the bearing.

[j2sip]

I'll be milling wood and if possible aluminum. Using spreadsheets that I found in the forum, I am able to go 350IPM with my setup and 1500IPM without the gear reduction!!!! I have already built an MDF router but got only as far as the machine itself. So if Sir Dave permits, his board will be my first!

Thanks,
Jordan

[diyengineer]

1. Stick with the 350IPM, you will get a lot of TQ with that gear reduction system compared to direct drive. 1500IPM is worthless because the table is so small i doubt the motors would even be able to spool up to the fullspeed before they hit a limit switch. Ontop of that you wont be able to cut anything @ 1500IPM and you wont have as much TQ when you are actually using the machine to cut. =)

2. The long chain on your X axis and Y axis both need chain tensioners. The smaller chain on the x and y axis that actually connects to the stepper does not need chain tensioner, BUT the motor mounts should adjust so can engage the gear into the chain, apply pressure on the assembly and then bolt it in. (basically instead of using 4 round holes to bolt the stepper in, use the same diameter hole, but make 4 slots for adjustment). Easy fix.

3. The front of your frame is split, you are really going to want to box the front of it in. Even if you have to build around your table chain, or in front of it would even be easier. Just make sure your frame is fully boxed, with that missing front connection it weakens the rigidity a lot. Easy fix.

4. The bearings should have a slight adjustment. 2 can be fixed in place, but the 2 across from the fixed ones should be slotted (the holes) for adjustment. Between things sagging, flexing, thermal expansion and contraction, dirt, grime, dust, wear and tear, you will NEED atleast 2 out of the 4 to adjust. then you can tighten them up when they get loose, or loosen them up if they get to tight. Without adjustment you would be really screwed =O

random ideas:
Start from the begining and you can see how i set up a machine that i was going to build before i went another route (link below). I modeled it in solidworks. Might give you some design help or ideas? It took many people off the forum helping me to get that design down. I pretty much took the best of everyones ideas and crammed them all into one machine. Lots of wisdom there. You can also see how the machine evolved and changed over time with better ideas and peoples comments.

http://cnczone.com/forums/showthread.php?t=100925

1. If you really wanted to you could look into belt drives instead of chain drives? Lighter weight, a lot quieter, cheaper to replace when they wear out, and no oiling or greasing.

2. If you didn't want to deal with the hassell of adjusting those bearings, and all that stuff you could just buy a set of 2 of these rails. The SBR-20's would be perfect for your build and all bolt on! A "set" comes with 2 rails and 4 bearing blocks. They are amazing, especially how cheap they are and how much time and frustration they could save you. (looks like for a little less the $300 dollars you could convert your X and Y axis over to them, 2 rails per axis and 4 bearing blocks per axis) (4 rails total with 8 bearing blocks)

Anyways, i tried to throw out as much wisdom your way as i could. =)
Keep up the good work! It's late and im tired haha!

Here is my current build:
http://cnczone.com/forums/showthread.php?t=103291
I didnt build the smaller cnc machine, because i bought this older monster that im fixing up. A lot of smart people and random knowledge on that thread as well.

[strond]

Just an update. I was able to email Dave. I ended up ordering his kit.

[diyengineer]

Just an update. I was able to email Dave. I ended up ordering his kit.

Nice! you will be pleased. You should be able to solder it together in a few hours. the instructions are very straight forward. Make sure to join his Yahoo group for questions. It will save you a lot of headache!

[j2sip]

An update:

I've already bought a hobbycnc pro kit thru a forwarder in our country. It's on the way and I can't wait to get started. It's been 2 years since I got interested in this product and have only ordered it a couple of months ago.

[j2sip]

My box arrived! A tube of goodies from Roton and a box of yummies from HobbyCNC. I wish I'd have free time to document my build.

[diyengineer]

Thanks, diyengineer. It seems Dave is busy, with another drive design perhaps? The keling 425oz-in or the 282 oz-in is what I'm eyeing at the moment. I understand that I will not be getting the full power of the motor if I use unipolar driver. Knowing that, my CNC will have a 1:4 drive reduction. Do you think it will have enough force to mill wood? and perhaps aluminum?

Id stick with the 282oz or less. I think the 425 is a little large for the hobbypro if im not mistaken.

It's a good kit overall, for the price it will get you started. it will work for wood or metal except you wont be able to take a huge bite out of metal. it depends on a lot more then just stepper power. rigidity will be your first enemy.

[j2sip]

I haven't registered to dave's hobbycnc yahoo forum yet so may I post this question here.

the transformer suggested in the hobbycnc kit is a center tapped one and I have bought a transformer that has only two secondary wires. can I use this? It's 24v 12amps.

Thanks

[j2sip]

I finally assembled the kit and all went well considering my noobiness. As long as you follow, i mean FOLLOW RELIGIOUSLY the included instruction, theres no reason for trouble. Is it ok to put it in a wooden case?

[WoodSpinner]

I finally assembled the kit and all went well considering my noobiness. As long as you follow, i mean FOLLOW RELIGIOUSLY the included instruction, theres no reason for trouble. Is it ok to put it in a wooden case?

sure, wooden case would look kewl, make sure to install heat sink and fans.

John

[j2sip]

sure, wooden case would look kewl, make sure to install heat sink and fans.

John

Thanks. I can't find a heatsink paste nearby so I have to go to the city this week end. The hardware part is quite manageable. I hope the software part too. I'll be using linuxCNC, heeksCNC, freemill and freeCAD. Oh the cheapier the better! It's only for fun anyway.

[j2sip]

Here's my completed kit. I now only need a suitable pc. The kit is topnotch!!!





A rendering of my design


It nedds some lovin'



I plan to use these for connections. i hope they are suitable.

[j2sip]

I've just finished setting up my board in MAch3 and it works!!!!!! NIce little board. I thought one of the steppers is not working. I tried everything to no avail.Then I tried connecting the stepper directly to the board and it did the trick. Im happy!