[bp092]

Thats a good suggestion glider, anytime I was doing more complex long programs and I wasn't so familiar with mach3 or cnc I would punch a hole with the machine on xyz0. If I ever lost that place for any reason whatsoever or I had to start again later, I just put it at that hole and I was always within a few hundreds of an inch

[joecnc2006]

Thats what i do jog to known coords. then punch in the right numbers, then go to 0's.

Joe

[Sbthomas13]

Thanks for the advice Glidergider and others! I will definitely try that, I'll set the bit in one of the corners of the pockets. Then I will zero it, and find the coordinates for that point in my CAM program, and then I will plug in the negative coordinates, tell the machine to go there, and then rezero.

Excellent! That sounds like a great solution. And even if I am off a few hundreths of an inch, like you said...I really only did the pockets and that should cause no problems.

[ZipSnipe]

Great build guys keep up the great work. I,m sure there are many of us here that envy you as back when we were your ages all we had in shop class was a handsaw and a hammer.

[Sbthomas13]

Today wasn't very productive and no cuts were made. It turns out the piece we were trying to cut out was too long for the machine, so I will have to break the CAD into two files.

Most of class I spent laying out parts and generating toolpaths. Towards the end of class I started to cut out the Gantry Veritcal Supports, but only the drilling was completed.

Tomorrow the Gantry Vertical Supports will be completed and while Tyler is watching the machine, I will continue to work on toolpaths for the End Support Pieces and hopefully we can begin to cut them or maybe finish them. We're running low on MDF, so we will probabably have to make a Home Depot run sometime this week.

[Sbthomas13]

No progress was made Monday as our tech teacher was not in school, so we had a study hall instead. However, today was one of the most productive days we have had yet!

With the toolpaths already generated, today we were able to cut out the Y Axis Gantry Torsion Box Vertical Ribs and the Gantry Bottom Torsion Box Cross Pieces. After we had cut out the vertical ribs, we decided we would install our new 2 Spiral CMT Bit, that Joe recommended. We started to cut out the cross pieces and the horrible sound disappeared! On top of that we were able to increase our cut speeds to 150 IPM, and it has potential for so much more. THANK YOU JOE!! for showing us this bit! It is perfect and it will definitely speed up our project.

While the cross pieces were being cut out, I split the geometry for the Gantry Horizontal Ribs. I split the CAD at 20" and we will use aolshove's method (Thanks for the help aolshove! we appreciate it) for cutting out the part. I was able to split the geometry and generate toolpaths in record time! So by the end of class we were able to make the first cut....so now, correct me if I'm wrong, I draw a line from the current origin up 20 inches...and that is the point I will then line up with the origin when I reposition the blank?

Tomorrow we will finish the Gantry Horiztonal Ribs in the first 10 minutes of class, and that means the Y Axis Gantry (without the sides) is done! We will also try to cut out the End Support Pieces which would mean the X Axis is done as well. And finally we will attempt to cut out the Gantry Bottom Torsion Box Long Run Pieces, which would complete the gantry bottom.

With all of this done we need to do the following:

• Skin X, Y Gantry, and Gantry Bottom Torsion boxes
• Cut out Gantry sides
• Cut out Z axis
• Cut out HDPE

We will order the hdpe sometime this week. I would just like to thank everyone on the Zone for the excellent advice they have provided. It's a great help! and we really appreciate it!

Picture 1: Cutting out Gantry Vertical Ribs
Picture 2: Cutting out Gantry Vertical Ribs (2)
Picture 3: Changing bit
Picture 4: New CMT bit
Picture 5: Old POS Enco 4 flute endmill
Picture 6: Cutting out Bottom Torsion Box Cross Pieces (150 IPM!)
Picture 7: Cleaning up completed parts
Picture 8: Y Axis Gantry Torsion Box Vertical Ribs
Picture 9: Gantry Bottom Torsion Box Cross Pieces
Picture 10: Completed X Axis Torsion Box (hahah just kidding, our classmates thought they would lend a hand and help us construct the machine....it didn't quite work out, but it's the thought that counts)

[Sbthomas13]

Can we skin the torsion boxes with 1/2" MDF? or does it cause clearance issues? Where do they sell 1/4" MDF?

[joecnc2006]

Can we skin the torsion boxes with 1/2" MDF? or does it cause clearance issues? Where do they sell 1/4" MDF?

You can use 1/2" MDF the only area you have to deal with is the X-Axis bearing adjustment box. but all you have to do is go ahead and make a 1/4" pocket on that one side to allow for clearance. very easy to do.

Joe

[joecnc2006]

Hey guys don't forget under my name on here is my yahoo, so if you have messaneger and need to chat or ask questions allot of times I'm on in the evenings.

Joe

[gacrwell]

Can we skin the torsion boxes with 1/2" MDF? or does it cause clearance issues? Where do they sell 1/4" MDF?

Found the 1/4 MDF at Home Depot in the shelving section, 4x8 sheets. It has a vinyl coating on one side that can be easily stripped off. The side under the vinyl is not as smooth as the normal MDF surface, but that side can be turned inward on the boxes.

Don't let your 'friends' in class near any glue.

Gary

[tybrenis]

Thanks guys. A ton of progress was made today on the gantry parts, but I assume Spencer will be on here soon with pictures...

[Sbthomas13]

Today we finished cutting out the Y Axis Gantry Torsion Box Horizontal Ribs. With Joe's reccommended CMT bit we were flying! 150 IPM, no high pitched screaming noise, no chatter, it was perfect!

Well the cut was about 80% complete when the cutting noise stopped..Tyler and I were like "huh?". Then as the gantry moved away, thinking it was still cutting, we saw our bit sticking out of the workpiece!! What had happened was the bit had came out of the collet and the top chipped off. It was probably the result of not chucking it up high enough (but I do recall myself jamming it up in the collet pretty well), because it was certainly tight.

Anyway, only a little chipped off so we just chucked it up farther and continued cutting and thing were good again! We completed the Y AxiS Gantry Torsion Box Horizontal Ribs...and we were supposed to cut out the CNC Router End Supports next, but we lost a good amount of time on the bit problem, and I still had to split the toolpaths. So Tyler wanted to cut out the Z Axis Side Plates, so I started to generate toolpaths for that...we will cut them out tomorrow.

At the end of class we assembled the Y Axis Gantry and it looks great!

P.S. We used aolshoves method of drawing the lines, and lining things up! It worked perfectly! Thanks!

Picture 1: Making second cut for Y Axis Gantry Torsion Box Horizontal Ribs
Picture 2: Broken Bit
Picture 3: Broken Bit (2)
Picture 4: Comleted Y Axis Gantry Torsion Box Horizontal Ribs
Picture 5: Another picture of completed Y Axis Gantry Torsion Box Vertical Ribs
Picture 6: Another picture of completed Y Axis Bottom Torsion Box Cross Pieces
Picture 7: Assembled Gantry
Picture 8: Assembled Gantry (2)
Picture 9: Assembled Gantry (3)
Picture 10: Assembled Gantry (4)

[Mr.Chips]

"With Joe's reccommended CMT bit we were flying! 150 IPM, no high pitched screaming noise, no chatter, it was perfect!"

I looked over the thread and did not find a reference to the bit, probaly over looked it. What is the full description of the bit and where did you get it?

Really good job guys, and I am getting answers for questions I didn't know to ask yet.

Thanks

[joecnc2006]

CMT 2 flute upspiral I get mine from woodcraft, i have one local.

Joe

[ger21]

(but I do recall myself jamming it up in the collet pretty well), because it was certainly tight.

Never bottom out the bit in the collet.It won't be able to tighten correctly, and the bit will come out. Always pull it back out an 1/8 or so before tightening, if it bottoms out.

[rdhharm]

You guys are doing an awesome job with this project

Now when you guys are done with Joes CNC is your teacher going to require you make something with your CNC to receive a passing grade?

I sure wish we had a CNC to use in wood shop when I was in school
But I had to walk up hill both ways that may tell you how old I am LOL.


Rick

[Sbthomas13]

Never bottom out the bit in the collet.It won't be able to tighten correctly, and the bit will come out. Always pull it back out an 1/8 or so before tightening, if it bottoms out.

Yeah, I made sure I didn't chuck it up all the way because it causes chatter in the bit... I just made sure it was snug in there...what I meant was it wasn't too loose, I definitely had the majority of the shank in the collet. But maybe I didn't leave enough space...yeah that was probably it, it probably got pushed up a little on the plunges or something, and then that caused it to bottom out.

[Sbthomas13]

Now when you guys are done with Joes CNC is your teacher going to require you make something with your CNC to receive a passing grade?
Rick

Hmmmm, I wonder. He probably will want to see us cut something out..but I think just jogging the X, Y, and Z will be sufficient. But we will definitely want to cut something out as soon as we finish.

Our deadline is January 28th: its definitely going to be a rush...and we only have 16 working days left in class. I wish I could do the toolpaths at home, but I dont have the right software. If we finish all the parts by Friday, January 4th we should be able to assmble over the weekends.

How long does assmbly usually take, in terms of hours?

[rdhharm]

Hmmmm, I wonder. He probably will want to see us cut something out..but I think just jogging the X, Y, and Z will be sufficient. But we will definitely want to cut something out as soon as we finish.

Our deadline is January 28th: its definitely going to be a rush...and we only have 16 working days left in class. I wish I could do the toolpaths at home, but I dont have the right software. If we finish all the parts by Friday, January 4th we should be able to assmble over the weekends.

How long does assmbly usually take, in terms of hours?

You guys have got your work cut out for you get it done it that time frame but I think you can do it.

I would have to say to get it in a rolling chassis with everything painted about 40 hours give or take.

Do you have your controller done yet? That took me some time because I did not want to make it go up in smoke.


Rick

[joecnc2006]

I would glue the torsion boxes, and take home for painting, and do the controller over the holidays.