CarveOne's Steel Channel Rebuild

[CarveOne]

This is going to be a complete rebuild of my first CNC machine, the red oak Solsylva 25x37. Stiffness and extra mass is the goal. Once stripped of useful parts, the red oak frame will be set aside for the time being. It will not be junked.

Some of the mechanical parts like the 5 start lead screws, anti-backlash nuts, bearings, and couplers will be re-used on the new version. The frame will be completely redesigned using 1.5" x 3" steel channel and 1/4" x 4" cold roll steel rails and Ahren's short bearing carriages.

The 5 start lead screws, anti-backlash nuts, and rails were removed from my Work Table CNC machine rebuilds (and upgrades) and will not be additional expense. The eight bearing carriages and the steel channel material were purchased in the past month. Around mid-January I'll order a Gecko G540 to replace the 3 axis Xylotex since the rebuild will use a dual motor X axis. The Xylotex 425 oz-in motors are probably not the best match for the G540 and are likely to be replaced with new motors.

So, over the past week I cut the channel to length (36" and 48") and mitered the ends at 45 degrees. Today I welded them together. That seemed to go well until the argon/co2 gas cylinder started running low on pressure. I barely finished and some of the welds inside the corners look ugly but will hold ok. 4" legs cut from 1.5" x 3" channel will be tacked in place tomorrow. Eventually, there will be leveling feet added to the bottom of the legs.

Tomorrow I'll attach the X axis rails. The three 1/2" holes will have washers and flat head machine screws through them. There will be four additional flat head machine screws installed into counter sunk holes.

As on my big machine, the rails will be vertically oriented and steel gantry supports will tie the upper and lower carriages together and also support the steel channel beam and rail. The beam will sit on top of the upper carriages. I'll build a new steel Z axis similar to the one on the big machine that can use the Hitachi M12VC router.

The first issue I found is that when the carriages are installed on a rail with a piece of channel between the carriages as shown in the three photos the bolt heads slightly rub against the channel. This can be used to help center the rail on the channel. The bolt heads need to be trimmed on the lathe by about 0.050" for adequate clearance after the rails are bolted to the channels. It will not affect using a wrench on the bolt heads. I'll just remove the "crown" a little.

I haven't decided on a paint yet. It will be either the textured silver, or a camo paint job.

CarveOne

[DIYaholic]

CarveOne,

I am so looking forward to following along with your trials and tribulations of your rebuild. I am sure we will all be entertained and educated during the rebuild process. However for us neophytes, could you tell us why you chose channel over square tube steel.
Good luck with the rebuild & thanks, in advance, for this sure to be riveting thread.

Randy

[CarveOne]

CarveOne,

I am so looking forward to following along with your trials and tribulations of your rebuild. I am sure we will all be entertained and educated during the rebuild process. However for us neophytes, could you tell us why you chose channel over square tube steel.
Good luck with the rebuild & thanks, in advance, for this sure to be riveting thread.

Randy

Mostly because the local Fastenal store keeps them in stock and they don't keep the 1.5" x 3" box tubes in stock. They will order them for me if I ask, and the 6' channels cost less. That size box tube in 0.180 wall also has a fairly large radius on the edges with less of a flat surface for the rail to fit against. I used it on the big machine's final gantry beam with no problems though. I used a 5" wide rail with it, so there was no issue with the carriage bolts rubbing the tube as this one does.

The channel certainly is not as resistant to twist as the box tube would be. The short lengths involved should be ok. The work table top it will sit on should prevent that from being an issue. The welded channel frame feels rock solid when lifting it by one corner. Once the spoil board is screwed to the underside of the frame with a few cross stiffeners it will become less of a flexing issue.

Builders with no welding capability can assemble the frame by bolting it together with four pieces of right angle steel inside the corners.


CarveOne

[Khalid]

OMG..Another adventure...Will closely follow YOU my friend..
How straight are the channels..also if you are going to weld the frame, did you get any war-page?

[The J]

My question is, why? You have a beautiful machine already, unless I'm missing something and your old gantry had a taller clearance than your lustful table (pictured above)...nom nom nom.

[Khalid]

i think he want to cut non-ferrous metals with it...

[archer3d]

Lookin good carveone, as for color I put my vote in for camo

archer3d

[CarveOne]

OMG..Another adventure...Will closely follow YOU my friend..
How straight are the channels..also if you are going to weld the frame, did you get any war-page?

Hi Khalid,

The channel is as straight as my ability to measure it with the straightest 48" aluminum rule I have. I will expect to install some thin shims between the X axis rails and the channel where it is necessary. I was able to weld it with no serious misalignment. I use clamps and check the alignment, then make short welds that do not heat the metal excessively. Heat control is the key to making assemblies that do not warp. If the joint is not aligned well enough, I cut it free and weld it again.

This is what we call "old school" construction. Aluminum extrusions are the current popular method of construction, but I prefer steel for a number of reasons other than the lower cost.

CarveOne

[CarveOne]

My question is, why? You have a beautiful machine already, unless I'm missing something and your old gantry had a taller clearance than your lustful table (pictured above)...nom nom nom.

The 12' machine was designed to reach into a 6" thick block of mold material by 5" deep. This new small frame machine will handle 3" materials. This smaller machine should have better accuracy and less chatter tendencies than the big machine. #1 reason is that I just like to build things and just can't resist the need to make my first machine even better than it was.

As "retro" as it may end up looking when compared to the 8020 builds, it should be a nice R/C foamy and guitar body making machine to use while the 10' commercial signs are being cut on the big machine for hours on end.

CarveOne

[CarveOne]

i think he want to cut non-ferrous metals with it...

Yes, definitely. Especially aluminum plate and bar stock, and also engraved brass sheet if it has enough accuracy.

I want a lower gantry this time.

CarveOne

[CarveOne]

Lookin good carveone, as for color I put my vote in for camo

archer3d

Mossy Oak, Realtree, desert camo or digital camo?

If I paint it with textured silver it will look like an all-aluminum build.

CarveOne

[revwarguy]

Just wanted to say good luck on this rebuild. As someone who followed your original oak Solsylva, this will be very interesting.

Since the old one was 24x37, how you going to use the old screws for a 36x48? Gonna stay with the belt for the dual X axis screws?

Anyway, bon voyage!