4'x8' RouteBot

[RouteBot]

All the steel parts were sandblasted and sprayed with phosphoric acid. In this picture I'm leveling the beams. I shimmed them level and clamped blocks to the saw horses. Once satisfied everything was perfectly level, the blocks were screwed directly to the saw horses and the clamps were removed.




Clamping and welding the first cross member. A 2x2 angle was used to support the 3x3 and keep it flat and square to the frame sides.




The top is done. Perfectly flat and square!

[RouteBot]

CNC table revised design. Now that the electrical parts will be in a separate box and will not be under the table, I changed the bottom to accommodate wood storage.



The table is ready for paint. It's nice to see the plan coming together!

[widgitmaster]

Nice job on the steel frame!
Widgit

[RouteBot]

Thanks Widgitmaster! That's good the hear from the master of steel! You have definitely done a lot with steel.

As a woodworker, I have been very concerned about welding the CNC table since day one. I bought a welder just to do this project and I didn't know how to weld! That's why I decided to build a welding table first as seen in a previous post. It taught me a lot about what I needed to do differently.

The welder I bought was a 2012 Hobart 140. I was disappointed when I found out that I had to use flux core wire on 3/16" and 1/4" steel (the 2013 model can use gas but the 2012 can not??). The welding table was all 1/4" steel and I had trouble getting the settings to work well. I friend offered to buy the 140 so I bought a Hobart 210MVP. What a difference! The gas and extra power made the welds much better. I think the 140 is a good welder but not for 1/4". If you need to weld 1/4" steel once in a while it's fine, but I was glad I didn't weld my CNC table with it.

I also got my steel sandblasted before welding the CNC table. On the welding table I used a flap sander on every part. I spent hours decreasing and sanding. Never again! It takes more time that you think to sand 4 sides of every tube. Plus it make quite the mess. The shop was black with dust.

Now I have to paint this beast. A friend offered to let me use his Bobcat fork lift. So I just have to wait for warm weather now.

[widgitmaster]

I envy your work area, Oh what I could do in a space that large !!
Widgit

[jharvey407]

This is a great looking build! Nice job.

[RouteBot]

The cold weather has prevented me from painting the steel table! So I started making the gantry parts. Here are some pictures. Special thanks to Colin for help milling the parts.



Rough cutting parts out of 1" thick 6061 aluminum with a 40 tooth woodworking blade.



Milling the gantry sides


Milling the gantry side support

[kevincnc]

Nice progress! I haven't checked in here for a while, now I need to keep an eye on you to make sure I get mine done first

[RouteBot]

Thanks Kevin! You better get on it. I may be slow, but slow and steady may win the race!!

[RouteBot]

Still too cold to paint the table! So I was able to get the gantry assembled today. It may be aluminum, but I figure it's about a 140 lbs already. It will be a little over 200 lbs once the z axis parts are installed.






Servo mounts to be milled next . . .

[RouteBot]

I finally got that table painted. The skid loader helped move the 1000 lb beast.



The paint is Restoration Shop acrylic urethane. Mopar sublime green. Not fun painting around all those tubes!

[CarveOne]

That's going to be a very sturdy frame and gantry. I like the color too. I just got mine running this week.

[Khalid]

Hi nice machine.
--> CarveOne: The color and Bed seems like you have gifted your own to routebot.

[CarveOne]

Hi Khalid,

I think Routebot and I are just on parallel paths with the chartreuse color. I had already purchased the paint in October 2013 but didn't mention the color until early February 2014 when I first showed the frame after it was brought home from the paint shop. When Routebot first showed his simulations in the neon chartreuse color it got my attention. I think there is one other build here that is using a similar color.

My frame has less cross members on the table top and lower shelf than Routebot just to save money because the paint job cost so much.. Routebot has done a fine job of it so far and will probably end up with a much smoother running machine than mine due to the rails and bearings he is using. Converting mine to THK style rails 12 feet long with servo drives is not going to happen on my budget - but it is nice to daydream about it.

[RouteBot]

CarveOne,

Thanks for the compliments! You have an awesome machine and the paint job is perfect.

I have to say you make this stuff look easy. Without people like you and others on this forum I wouldn't even know how to start. Building a custom CNC router is a long process. It's a bit overwhelming and expensive. I thought I would be done in a few months. Ha! A year has now passed and there's still a lot of work to do. Other things keep coming up and delaying progress. I'm $15,000 in the hole now so its become a quest to finish it. I hope it works!!

[RouteBot]

I have been busy getting the rest of the gantry parts milled and assembled. The next step is assembling the aluminum extrusions to the sides of the table.




Three servo mounts being milled out of 3/4" 6061 aluminum.



Servo mount bolted to the 10:1 gear box and servo motor. The assembly weighs 18 lbs.



Servo mount assembled to the gantry side.



The mount will pivot, allowing the pinon gear to engage the rack gear.

[nlancaster]

Routebot, I love the way you have positioned your gantry drives. I take it you are going rack and pinion correct?

That is going to be a really compact installation, no big motors hanging off the dies of the gantry

[RouteBot]

nlancaster,

Yes, it will be a rack and pinion drive. The table is 10 ft. long so I decided that would be the way to go. So far it looks like it will work. I was concerned about the mounting being offset from center. It had the potential of making the servo hang at an angle. However, it looks okay and the servo hangs perfectly 90 degrees to the side.

[RouteBot]

After a lot of work I finally have a rolling gantry. Both 3 x 6's had a 1/8" concave bow in them. That caused the side extrusions to be tilted outward. I tried to shim the extrusions but it was difficult to get it right. I decided to use epoxy and fill it in. Then I flattened the sides after a LOT of sanding, repaint and bolt the extrusions on.




With a 10' long rail and no edge guide I decided to do the piano wire trick as a guide.

To bolt down the rail perfectly straight, I used a piano wire pulled tightly. A razor blade was mounted to the bearing such that it would sound a buzzer if it touched the wire. This allowed me to move the rail till it sounded the buzzer, then pull it back until the buzzer stopped. I tightened each bolt as I moved down the rail. Knowing that the rail was straight, I was able to walk in the other rail with the bearings mounted to the gantry.




It's finally starting to look like the model. I have a few more z axis parts to cut then I'll assemble them and look into the electronics and software. Is Mach4 ever going to be ready??

[pippin88]

Neat trick with the piano wire and buzzer