CarveOne's Steel Channel Rebuild

[Khalid]

very nice build so far.. CarveOne, watching your work on this machine stressing my mind to make similar but in smaller version for making molds of steel and Aluminum.. currently stuck whether i have to make a mill like X3 or the router similar like your this one...

[CarveOne]

Looks good Carveone, I will also be going all steel for frames. I am an old school welder and have my own gas drive setup. I used to do pressure welding up to 7500psi so I think I can put this together square, an old millwright told me.. "put a tack here and one opposite, work your way around with tacks to keep things square". It has worked for me so far.

I will also be using cncrouter parts for the x and y axis bearing slides, I like how they work.

Just as you are doing, I want to be able to do aluminum and alloys when I have to for panel work I build electrical and hydraulic/pneumatic panels for a day job so I want a rigid setup to do this. Keep up the good work, I will be following your progress.

Auto

I hear a lot of warnings about welding on the CNC Zone, and to stay away from it because of warping. My thought is always "Then how have people been building precision weldments all these years?" It's all in how you go about doing it, as in everything else. This frame is not absolutely perfect, but it is my own fault for lack of a good welding jig to hold it straight, and not having the proper gas flow. The MIG gas cylinder was almost empty from building the 12' machine's frame and I used up the last of it this time. I'll get another cylinder in the coming week. Though the frame is off a little it is something that can be compensated for in an acceptable manner.

The procedure that you mentioned is the one that I also use to compensate for "pulling". It works quite well.

I think I am about the only one here that uses vertical X axis rails for my machines that uses cncrouterparts.com bearing carriages. It puts all of the gantry weight on the two bearings in the top carriages that roll on the edge of the rail. The lower carriages don't support any weight, just keep the gantry support square and prevent lifting when plunging the cutter into material being cut. The horizontal rail method that Ahren recommends and FLA uses can support more weight because four bearings in each carriage carry the load.

I haven't had any ABEC7 bearings go bad so far, just wanted to point out this difference.

If you are going to cut steel, then I would recommend using thick wall box tubing for the frame instead of channel as I am doing. It is generally straighter than channel, and 3/16" or 1/4" thick wall tubing will be a lot stiffer. Bevel the edges that are to be welded so that weld penetration is better. That too is a normal welding procedure, as I'm sure you know.

Be sure to post your build here, of course.

CarveOne

[CarveOne]

carveone,

being tucked away in my "subscriptions" i forget to check the main forum from time to time, you mentioned some thing about it in your other build,or i would have never known you were redoing the solsylvia, looks like a good solid start !

Yeah, I'm still having too much fun in the shop. When this one is running I'll back off the new builds and rebuilds for a while and just add some convenience features to both machines. I have mentioned it from time to time over the past year and did a quick upgrade to 5 start screws last year. The wood frame is entirely usable as it is but I want it to be better, so here we are once again.

CarveOne

[CarveOne]

very nice build so far.. CarveOne, watching your work on this machine stressing my mind to make similar but in smaller version for making molds of steel and Aluminum.. currently stuck whether i have to make a mill like X3 or the router similar like your this one...

If you want to machine molds from steel, a CNC milling machine will give you much better finish cuts in mild steel. Cold roll steel is going to be a little tougher to mill but it will give you better finish cuts. CNC mills normally have a smaller working area in the Y dimension (front to back). If you build a fixed gantry machine from thick plate steel I think that you can get reasonable results and have a working area that is closer to a square. I think keeping the Z axis rigid is going to be the hardest to achieve. You would probably be better off to buy a mini-mill head from LittleMachineShop.com - tooling, parts, and accessories for bench top machinists (or find a used mill head) for your Z axis. A moving table will also require a very rigid method of movement. Milling machines have dovetail slides that support a lot of weight and can be adjusted to take out any backlash. That's going to be hard to do without fully supported large rails.

CarveOne

[Khalid]

I have recently purchased ball screws and linear rails for my machine..they are in excellent conditions... Also received G540 from Gecko and 3-G540 compatible motors (380 oz-in) from ahren of cncrouterparts...These motors are on the way along with 12 feet cables...

All i have to do know to make a rigid design similar like:
http://www.cnczone.com/forums/vertic...rogress-3.html
in later pages, you will see some of his fine work out of this machine...

[Khalid]

Actually, i am also worried about the straightness of these C-channels you are using...

[CarveOne]

I have recently purchased ball screws and linear rails for my machine..they are in excellent conditions... Also received G540 from Gecko and 3-G540 compatible motors (380 oz-in) from ahren of cncrouterparts...These motors are on the way along with 12 feet cables...

All i have to do know to make a rigid design similar like:
http://www.cnczone.com/forums/vertic...rogress-3.html
in later pages, you will see some of his fine work out of this machine...

Those are what I will also get in mid-January for this machine.

Yes, rigid is the key to making good cuts with milling cutters. That and having a spindle of some sort that runs at the proper speeds for milling steel.

I haven't been following the metalworking threads very much partly because I have two nice milling machines already, and partly because I am afraid of how much money it will cost me.

CarveOne

[CarveOne]

Actually, i am also worried about the straightness of these C-channels you are using...

I didn't have the ability to check them at the store when I bought them other than to look down the edge from one end. They looked straight, but when I put a known straight bar of aluminum against the channels they are not so good. I will just have to deal with it by using metal shims. Once the carriages are bolted together with the gantry supports I can find ways to make one rail straight and 90 degrees to the work table top. Then I can make the other rail match it as close as I can. When the gantry rail and beam are bolted onto the gantry supports the task will be to remove any binding that may happen along the X axis travel. I won't do this until the machine is sitting in the permanent location on another work table in the work shop.

I cut the support plates this morning and will drill the holes for mounting them to the carriages next.

CarveOne

[CarveOne]

This is starting to look like my fastest build yet.

I made the gantry support plates today and they fit as intended. Relative to the table top it is sitting on the gantry supports are nearly perfectly 90 degrees to the table top with the carriages at mid span. There is a barely perceptible gap when a machinist square is used to check it. I'm going to accept it as is and cut the channel for the beam and square up the ends, making the beam a few thousandths short on purpose. The reason for this is that I intend to make connector plates (1/4" thick this time) like I did on the final version of the big machine gantry. Screws will bolt the gantry connector plates to the gantry supports, and the connector plates will be welded to the beam and rail. This also lets me have it all assembled and clamped in alignment before tack welding. After welding it is possible to easily remove the gantry and Z assembly without disassembling the carriages and gantry support plates. This method worked really well previously.

I included a new photo of the red oak Solsylva 25x37 machine for reference. You can see some of the differences in the old versus the new replacement frame more easily.

CarveOne

[revwarguy]

This is starting to look like my fastest build yet.
CarveOne

That's saying something, given how quickly you knocked out your drum sander! And that was just lumber - I figure the time difference between working in wood vs steel for me is 100x. It looks like its 1x for you. Just keep Murphy away for a few more days...

Great stuff!

[Arbo]

Ah, another one to follow. Man, to think I almost missed the fun. Signing in...

[CarveOne]

First thing this morning I had no gantry parts other than carriages. Now I have a gantry too, though it's just sitting place.

The two photos where there are four carriages on the rail is when I was keeping the rail aligned with the channel and checking for clearances. The two photos with just two carriages are like it will be in use. The black screw threads will be cut and ground flush with the rail. The 3/8" holes in the rail were already there and threaded so I used 3/8" button head socket screws with split lock washers installed from the rear. I notched the bottom corners of the rail so that the channel sits directly on the carriages.

It would be possible to mount the rail and channel to the gantry supports with pieces of 1/4" thick steel angle brackets front and rear bolted together and to the gantry support plates and I think it would be plenty stiff enough. Making the 1/4" thick plates to fit the shape of the rail and channel as a unit will be a fairly complicated milling operation, but one that I prefer to do for this machine.

I'm almost waiting for Khalid to ask me to vcarve a small version of the Aztec calendar in a piece of the 5/8" cold roll steel bar stock just to see if this thing can do it. By now it's getting very heavy and there is no Z axis assembly and router on it yet.

CarveOne