Thx dddman, I am still contemplating price vs waiting a week...

 

Shipping, duties, etc. across the border can be ... tough. Kind of takes the "free" out of "Free Trade", eh ?

If you are not in a rush, wait the week or so. But be quick, some of these items go out the door faster than they come in.

 

So my wife came in from work late last night and brought in two packages that UPS had left on the porch. The first order from OpenBuilds and the order from McMaster-Carr. You guys ROCK!!! That was some fast shipping; next-day, wow. Thank you.

 

Serge, because I am waiting on the Gantry plates from Chris, I decided to wait for the last v-slot and get it from OpenBuilds. Thank you for identifying another avenue for parts though, it is always nice to know you have options when needed

Also, Once I get everything and begin my build, I will start a build thread in the forums.

 

Chris, do you (or anyone else) have mounting plates for the Harbor Freight trim router and/or the Rigid trim router? I have a HF trim router that I used on a door hinge project and can use that temporarily until I decide to get the Rigid. I don't want to use hose clamps....

 

I'm a new member and I need help finding a source for V-slot aluminum. By the way take it easy on me I'm a 85 year old novice.

Thnx in advance.

Forgot to sign in; dalgibbs

 

dalgibbs, click on OpenBuild's parts store (if you're in the US)....

 

Hi Rich,

Yes, I am making mounting kits for many types of routers... I have made and sent out 4 different types so far...
Makita 700c
Dewalt 611
Bosch Colt
Bosch 1617

Looks like I may have one more to add to the list lol
Chris

 

Two actually... I will take one for the Harbor Freight trim router and one for the Rigid trim trouter just as soon as you can make them

Rich

 

Does anyone have the body diameter of the Rigid trim router?

 

@dalgibbs where are you located?

 

I'm sure Chris can make you one, but I wouldn't waist the money for the HF trim router. Mount will cost you more than the router and you'll be buying another soon. Chris does good work you won't be disapointed with the mount but I would go ahead and get the Ridgid if thats the way I was going and get Chris to make a mount for it.

 

I was just thinking, because I already have the HF router.....besides, having both would:
A) save the cost of the Rigid initially
B) give me options
C) give me a backup

 

Chris, if nobody identifies the diameter before tomorrow, I'll run down to Home Depot and get a measurement for you.

 

Rich, don't get me wrong I buy some things from HF too, but the first time the HF router shells on you in the middle of a job and ruins the part and your out the cost of 2 mounts plus the cost of Ridgid router, I just don't see the savings. But that's just my opinion.

 

Thnx for the reply. I am located in Kenyucky.

 

Hi Rich,

I think Paul is right.... use the money you would have spent for a second mount kit towards a good router.... you may not need one as nice as Paul's Bosch 1617 in the picture I posted, but something a little more durable than the HF Trim.

 

Well I'm a new old guy (73) and I'm having a try at CNC. I live in a Retirement Village in Melbourne, Australia & space is very tight. I built it where it is, but it will move to a shed to work.
I got the plates off Anthony (asb-79), and started from there. He has been a great help in helping me source parts as well. I tried to follow the video as best I could to build the OX. When it came to the controller card, it was suggested that we use the same sort as the Shapeoko, but they were out of stock. The Shapeoko people suggested the tinyG. So I bought one. After we (the video and I) completed the mechanical construction, the fun started. I thought I should be able to duplicate what was shown on the screen! I fumbled around for some days before a nice man (chmr) rescued me by pointing out that the tinyG was quite different. I started using TGF X and everything has been fine since then, except for the Z axis.
After I fitted the second set of eccentrics I fitted a pen to it and printed the Shapeoko test pattern. Great Joy in the household!
One exception. The carriage won't stay up. It falls down under its own weight and with the Makita fitted it is hopeless. Now I read that people are fitting a Nema 23 to solve this problem. I do not understand how this can stop it. Can someone please explain how that will solve the problem without power being on.
Personally I think that the Acme thread is too fast. But I have a real problem trying to understand what the Acme terms mean, for instance, in my Mendel Max printer I use 10 x 2 in the Z axis i.e. 10 mm in diameter and a pitch of 2 ( one revolution advances 2 millimetres). However, the Acme in the Z axis here is 8 x 8 with a pitch of 2??? I saw an explanation in one of the earlier entries,but I didnt get it! I think I'm getting thick!
What I think I should do is have a slower pitch like my Mendelmax and that should stop it falling down. I would appreciate your opinion.
As you can see in the photo I am using the bracket designed by Anthony to hold the Makita in place.
I believe that tiny G will be able to handle the current drawn by the Nema 23s, if sufficient cooling is used. To that end, I've mounted the card about 30 mm off the bottom of the case and have mounted a 70 mm fan, so that I get cooling top and bottom because it has large heatsink pads on the bottom surface. I'd like opinions on that as well,please.
A rather rambling introduction, I'm afraid, and I don't think it will get any better!
I am very impressed with this design and I appreciate the fact that it's been made available to us. Thank you. [

 

Excellent work @gwandad a machine to be truly proud of.

The MEMA 23's have slightly more magnetic de-tent when in the off condition but I would be inclined to use a finer pitch of screw for the Z axis.

Tweakie.

 

Aha. Thankyou. I get it now.

 

Can I respectfully suggest that the recommended Acme screws in the Part Store be changed to, or added to one more suited to the job for the OX?

 

I've been lurking here a while and my machine is coming along. I really need to start a build on it as the design has changed a bit from the OX. It still shares the same basic setup for linear motion, same number of wheels and same configuration. I'm finally at the point where I can do some assembly and verify the design. Its really been a fun project, lots to learn and lots of problems to solve.

This is the X/Z cart:


When I did the CAD drawings I put the holes for the eccentric spacers centered on where holes would be if there were no eccentrics. So in theory I'd get 1/2 the adjustment toward the rail and 1/2 away. I didn't really know what to expect and wasn't sure how to measure so I went off the CAD drawings provided by OpenBuilds.

What I found is that the two rails I have are slightly different heights. One is nearly spot on 60mm tall, give or take 0.05mm over its length. The other is about 59.6mm tall on average. Unfortunately that 0.4mm difference is enough to put the part just out of the range of adjustment on my eccentrics. So if you are designing your own plates you want to err on the side of more adjustment towards the rail (3/4 should do it). I'll be making the adjustments to my plans before I release them. If you have one rail that doesn't seem to play nice, try putting some calipers to it and see if its smaller than the others.

The 80x20 mm sticks I have are black anodized and both are spot on 80mm (+/-0.05mm). I've ordered some more 60x20 mm in black to see if I can get a piece thats closer to true dimension. A $25 piece of rail is cheaper than throwing $200 worth of custom water jet cut Alu in the recycling bin.

I haven't tried any of this yet for myself so you can take this with a big bag of salt:
On the subject of the z-axis: I'm using 4 start 3/8" ACME rod and parts from Dumpster CNC. This is fast rod, 1 turn = 12.7mm of travel. Thats faster than the 8mm rod in the parts store. At 200 steps the smallest height increment is 0.0635mm. If your want to carve 3D stuff them you probably want a Z axis that can match the speed of the other axes, otherwise that will limit the overall speed of the machine. If you are going to use the machine like a mill, for flat stuff, then Z speed is not really a consideration. The 20 tooth pulley in the parts store has a pitch diameter of 19.10mm. So the smallest increment you can resolve on the X and Y axes is ~0.1mm. So the pulleys are still around 2x 'faster' than either rod.

Configure your machine for the jobs you want it to do, thats the beauty of DIY machines.

 

Sage advice @Gareth

Tweakie.

 

This is more a query than any thing else.but using a z axis that fast will certainly be a bigger problem than the 8mm I'm using, so how do you support the router? I can set, via tgFX, the Power Management to have the "motor on active", or "power always on". Question: Is having the power always on a problem? I have zero experience here, but if it is not a problem, then the speed of the Acme rod doesn't really matter & I've been chasing a "red herring".

 

I had assumed motors were always on even on the X and Y axes. Is this not a valid assumption? X/Y don't have much holding them back other than the stepper. A spinning tool bit should be able to move the Y axis without the stepper holding it.

I don't know how I will handle turning the power off when shutting down the machine. Maybe I will have to use some kind of physical axis lock or something.

 

If it's any help - on ballscrew driven, servo operated, machines it is common for them to have an electromagnetic brake fitted to the Z axis motor to prevent the axis downward travel when the machine is shut down and power is removed.

Tweakie.

 

You are right, the motors are powered during the print, but setting home before a print..oops! job is virtually impossible with the z axis, without fudging it. I guess we can change the gcode to stop it somewhere off the work area at the end. I did some snooping around CNC kits today & found Shapeoko uses 2.1mm per rev, as do a few more including the smaller Fireball ones, then the larger ones go up to 5mm per rev which was the fastest one I could find. Not all of them list the speed, just saying things like precision acme etc. I've ordered a composite motor & shaft of 2.0mm per rev plus an extension (dual shaft) so I can fiddle with the start to my hearts content! Gareth, I wish you all the luck in the world in your quest for speed & would be very interested to find out what you achieve, so please let me know. This reminds me a bit about the story of the old bull & the young bull.... I'm outa here, Thank you all.

 

Thanks gawndad! I'm probably going to find out something I don't like! I'm ok with that. The machine design wont have to change. I can swap the rod out easily enough to a finer pitch if that ends up being more practical.

 

I wonder if I could go off subject a little please - Im building my OX & the kit came with Mach3 - Im new to routing/CADCAM & a little surprised at the complexity. (Come from a plotter background) Can anyone recommend a good SW for a beginner to designwith & drive the router please?