View Full Version : New Machine Build My 4x8 project has started

05-14-2011, 04:43 PM
Well , first I want to say a big thanks to all of those who have posted thier projects here , lots of great info ! I spent a year dropping in here reading , I was on the fence about it , then I got the fever to do it , so here I go !
First my welding fabricating skills are good , My electronics skills are low, so you guys are need to help me there ! I ve never even seen g code / mach / sheetcam software so thats gonna be a little scary .
After reading a few things being said by you guys stuck in my head .
Gantry should be stiff as hell , but light weight
For the gantry I choose a 40- 4080 extrusion from 80/20 on e bay it was 69 inches long [ to be cut to length later ] Bolted to this was a ivtaaqr rail from pbc linear its nice and wide and fits the 80/20 perfect for a super stiff gantry

05-14-2011, 04:47 PM
The gantry with the z drive , less 2 motors came in at 44 pounds .

05-14-2011, 04:51 PM
The gantry extrusion was cut 61 and 1/8 inches long

05-14-2011, 04:58 PM
For the table , I used 2x2 14 ga tubing for the horizonal frame , 2x2 x 1/4 for the legs [ scrap i bought cheap steel is expensive !] and a 3x2 x 3/16 horizonal top tube for the rails to bolt to

05-14-2011, 05:11 PM
On top of each leg I welded a 3x 4 -5/8 x 3/4 thick pad . I only welded two sides , I came in 3/4 inch on each corner and drilled 4ea. 3/8 hole . Weld on the sides opposite the bolt holes
I also welded some feet pads out of 1/4 to the bottom in case I decide to mount it on wheels

05-14-2011, 05:23 PM
After the 2x2 tubing was all welded up it was time to bolt on the 3x2 tubing to the top of the leg pads . First I drilled all the way through the 3 x 2 tubing with a 3/8 bit . Then so the socket head of the bolt would go through the top only , I drilled a 1/2 hole only in the top .
I then bolted the pads to the tubing nice and flush , then clamping some spacer tubing to the horizontial frame for nice and square spacing , I tack welded the pads to the legs . I then loosened all the bolts so I could true / shim everthing nice and flat and square

05-14-2011, 05:31 PM
Heres how I made it perfectly flat . I was surprised how bowed it was . Some guys suggested using a piano wire . I could just see all the wasted time and looks I would get trying to procure such and item in this rural area ! So I used a masonary string stretched with a 25lb weight . I clamped a 1/2 plated to each end , then used a 1/2 pipe to gague the bowing .

05-14-2011, 05:35 PM
Her you can see some of the shiming . You will need to shim it perfectly level in both directions . This process took me about 3 hours some legs needed hardly nothing and some needed more

05-14-2011, 05:38 PM
After the 3x2 top tubing was set perfect it was time to paint !

05-14-2011, 05:54 PM
For the z drive and the gantry end plates , carriage plate and motor mounts I used No Sleep Studios product . I decided this would save me a tremendous amount of time with trial and error , I could of made them ,but I'm glad I found No Sleep Studio on this site ! The parts were well packaged and J. B. is a nice guy !:cheers:

I also bought his floating touch and go plate which I attached a torch holder I made out of a 1 inch two piece colar from ace hardware . The colar is welded to a 1/2 plate piece which is drilled for two bolts .

I ran into clearance problems , so I made a spacer plate out of 1/2 aluminum to raise the z drive up to clear the table , seems real stiff hope it works !

More to come !

05-14-2011, 06:07 PM
i am making my new Mill CNC machine .... and i have some problems in finding the calculations as there is many formula for one thing... i want to know a calculations of stepper motor ... as how to calculat its torque, watt, ampere and voltage to select for it the driver then the interface board.. and thanks

05-15-2011, 03:34 PM
For the y rails I used pbc linear ivtaas rail . I ordered it on a Monday and got it four days later ! Although the truck driver left them 7 miles from my shop at a hardware store , wizzes me off when thier too lazy to bring it to my shop .
Since the 3x2 top tubing rails were already trued , leveled and squared installation should be easy . A transfer punch would be real nice , but I didn't have one to mark all the mounting holes , so I marked all the holes with a pencil and a punch . I borrowed a friends magnetic drill press to drill 72 holes .
Since the tubing was 3/16 thich I used a 1/4 -28 thread tap for more threads . I started hand taping them , then I thought why not use a cordless drill ? Well in 8 minutes I tapped 21 holes then came number 22 :boxing:Snap ! not good it broke off . After some patientce I got it all out , and continued to hand tap the rest . Tap magic is wonderful !
Here you can see the v rail hangs over 12 inches from the end of the head of the table so I can cut all the way through a 8 ft sheet .

05-15-2011, 03:49 PM
I snugged the bolts down in a few locations and checked the width of the vee rails as well as level , no shimming or adjustments were needed .Here you can see one way I checked the squareness of the gantry .
I clamped some spacer tubing to the end of the table and man I was off ! What the heck is wrong , I added spacer washers to vee rollers and end of the gantry for three hours and it worked . But I looked at it and was not happy since this threw off the spacing of the gantry end plates . I took the end plates off and saw the squareness of the cuts to the ends of the gantry extrusion were very slightly out of square , no way was this little bit making me so bad out of square or so I thought .
After putting on my reading glasses [ this helps tremendously !] I hand filed it perfectly square in two directions . Bollted the end plates on , and man it was perfect !:D

05-15-2011, 03:58 PM
Heres a break down of the time so far actually building the machine . This does not include all the parts procuring .

Fabrication of table 2 days , includes truing top 3x2 tubing
Priming 1 hour painting 1 hour plus dry times
Mounting y vee rails and gantry installation 1 day
Making adapter plate for z drive and misc other fiddling 1 day
So I have about 4 days actual build time to this point :cheers:

Next is ordering in the gear rack from Moore Gear

05-15-2011, 08:35 PM
Table looks great so far metalhead...I can second J.B's kit being a great time saver and it was definitely money well spent!

I can't believe you got your rails in 4 days, mine took just under 7 weeks from PBC :eek: but they are also worth it and I would probably buy them again.

Look forward to see the table in action.

05-25-2011, 09:32 PM
Thanks Corbetti , I got the gear racks today from Moore Gear . Man they don't take any chances with flimsey boxes , I have enough wood from the crate to build some shelves for the shop ! Lots of stickers telling the shippers not to f it up ! Also ordered a dragon cut , mach 3 and sheet cam from c andcnc .

NIC 77
05-29-2011, 07:56 PM

I'm about to start a 4 x 8 cutting area shopdroids build myself. It's going to be for Routing and Plasma. The one weakness, in my opinion, of using the shopdroids design for larger builds is the lack of stiffness. An aluminum T-slot extrusion 2 inches by 2 inches could have alot of flex over a 4 foot span.

I'm not sure if this is an issue for plasma as I'm guessing the forces at the cutter are negligible compared to those generated by routing.

I've spent all my free time this past week reading and designing, and thinking about ways to stiffen up the IVT rails. For the past 4 days I've thought that I would be ready to place an order for the IVT that day, but I kept having one more thing to figure out before I would be ready to order my rails cut to the exact length I'd want.

I have already ordered my Router kit parts from Shop Droids and that should be arriving in a day or two.

I've decided to go with a welded steel support frame for the IVT rails instead instead of using 80/20.

About 5 minutes before reading this thread I thought I was ready to send in my e-mail to order for the IVT, but now I need to know something first.

My question for you is this:

The normal Pacific Bearing extrusion for the shopdroids design is the IVTAAG rail that has an "R" dimension of 64.95 mm.

The IVTAAQ rail that you are using for your gantry has an "R" dimension of 104.95 mm.

How did you get the shodroids carriage to work with the extra 4 cm rail width? Was it a custom kit? Did you move where the holes go? From the one pic I can see of both sides of the gantry carriage, it looks like it fits perfectly.

If you could please take a minute to explain how you did this I would really appreciate it. If I can make the IVTAAQ rail work for myself as well, then that's what I'm going to do and I really need to get these rails ordered.

Thanks in advance.

05-29-2011, 09:27 PM
Yes , I figured out in my design stage that a wider stiffer gantry was needed for my table , yet super light weight . You are correct J . B. made a custom carriage plate and gantry end plates for my design . If you talk to him tell him this and he will know what to make you . There is no slop in the carriage , you us 2 concentric bearing bushings on the bottom of the carriage and 2 ecentric on the top .

NIC 77
05-30-2011, 12:31 AM

First off, thanks for the prompt reply. I've been thinking of little else since I wrote my last post. I think I'm going to order my rails tomorrow. Unfortunately, I already ordered the standard Carriage size kit. I did not know this option was available when I ordered. It should be arriving tomorrow or the next day I figure.

Right now what I'm thinking is I'm going to order the IVTAAQ rails for the gantry and the IVTAAH rails for the other two sides.

This means I'll need a new Gantry carriage. I'm either going to make one from aluminum (should be easy, I just need to drill 4 holes) and bolt on the shop droids motor mounts to it, or e-mail shopdroids and see if he will make me up just the one piece I need. What I need to do should become apparent once I get some parts in my hands.

Also, I won't be using any T-Slot, I plan to bolt a 3x3 piece of steel square extrusion onto the IVTAAQ rail and weld that directly to the other two carriages.

Obviously, the gear rack will be mounted half an inch higher than for the original shopdroids design. I figure I can do this with a half inch spacer made from aluminum. I don't know from your posts if you have figured this all out for your design, but I'm guessing you will need to do the same.

What do you think of this idea? I value your input. Thanks again.

05-30-2011, 08:26 AM
Personally , I would not weld the endplates on , that has to be perfectly square , true , and level . I cut mine crooked , and was out of square bad , so I hand filed the ends perfectly square .

05-30-2011, 08:43 AM
I picked this up a few days ago , and haven't had time to use it yet :banana:

NIC 77
06-03-2011, 01:42 AM
Hello again,

Not trying to hijack your thread and turn it into a thread about my build, but seeing your pic of the IVTAAQ rail mounted in post #1 has caused me to redesign my whole project.

The Pacific Bearing website does not show the IVTAAQ rail with an alignment tab in it's drawings. Also, if you go to the cad drawings section it gives the option to add a tab (or two tabs) on all the other rails of that family, but not on the IVTAAQ.

Was there anything special you needed to do to get that rail made up with an alignment tab so it would fit with the 40 series 8020, or did you just specify the alignment tab option in the ordering code and presto?



06-03-2011, 01:47 PM
No . it fits perfect

06-03-2011, 04:26 PM
what type of stepper motor you used (how many oz-in...).Thanks

06-03-2011, 06:50 PM
I m using 600 oz. motors , dragon cut kit from c andcnc

06-10-2011, 11:19 PM
NIC 77 stated:

I'm about to start a 4 x 8 cutting area shopdroids build myself. It's going to be for Routing and Plasma. The one weakness, in my opinion, of using the shopdroids design for larger builds is the lack of stiffness. An aluminum T-slot extrusion 2 inches by 2 inches could have alot of flex over a 4 foot span.

NIC 77, I am builting a Shop Droid for routing that is 83-inches by 53-inches. I use 3030 t-slot from 8020. http://www.cnczone.com/forums/cnc_wood_router_project_log/121556-shopdroid_%5Bcustom_sized%5D.html

I did moment of inertia calculations on the 83-inch length and with the use of a leg in the middle got the deflection to 3/10,000-inch assuming a load of 500-pounds evenly distributed, and support only at both ends and in the middle, and this did not take into consideration any of the cross beams which reduces deflection even more.

Though I do not have the statistics for the material you are going to use, my suggestion to reduce deflection to next to nothing would be to put a leg in the middle of both the sides. The deflection over two-feet will be almost nil. The deflection over the 8-foot side will be almost nil as well.

NIC 77
06-11-2011, 09:25 PM

I've replied to your post in your build thread. I don't want to hijack this thread any more than I have with my long winded comments, and I've got alot to say about your post.

07-29-2011, 10:25 PM
O k , boy what an experience this has been . Newbies heres some info , after the table is built thats the easy part [ more on that later ]. But today damn it ,I roboticaly designed and cut my first part !!!!:cheers:
Heres a pic of third cut on my slat design

07-29-2011, 10:53 PM
B y part three the outer part just feel off , so cool ! Stiil gotta lot to learn .

I had never seen sheet cam or a design program or mach till a few weeks a go . I kept telling my self , something my 84 year old former brick mason father in law told me once . I ask him how he learned the trade , he said I saw some brick masons working one day and I just told my self that if they can do it , so can I !

07-29-2011, 11:04 PM
O h what a roller coaster week it has been , My primary business is sucking bad right now :(, due largely to the idiots running the country . So I tried to stay up beat , but it was very hard . I got stuck on numerous little details trying to get the machine to cut , so now at this very monent , I will open ice cold beer number three !:banana:

08-01-2011, 03:33 PM
Slat jig I made

08-04-2011, 09:40 PM
Slats all installed , Homing switches mounted on hard stops I got the d t h c
running today .

08-10-2011, 06:51 PM
320 ipm ,direct drive ,this is how it fell out of the sheet untouched .
I thought this was pretty good for a complete rookie , who never saw sheetcam , mach , candcnc stuff until a few months ago .

Belt reductions are currently being built

01-15-2012, 05:43 PM
Still tinkering with my machine . I scored a water tank from Culligan water ,dumpster diving . Its a wellmate , heavy fiberglass 120 gal . about 600.00 new , I got for free . They didn't know what was wrong with it , turns out a busted pvc fitting on the outside of it :cheers:.
Added a swivel monitor stand , e trac on y so far . shelves for my cpu .

01-16-2012, 06:27 PM
Looks great! Simple and obviously very effective.

01-26-2012, 09:10 PM
I m using 600 oz. motors , dragon cut kit from c andcnc

I am also very new to this...I have a little corel experince making the dxf files etc...but none with the sheetcam...when you put a dxf file in the sheet cam does it automacticly change to the code so the machine nows where to start? ordering my parts tonight thx for any advice or info

01-29-2012, 05:52 PM
No it does not do that . You must set up your table dimensions in sheetcam first . Then you import your dxf file . As its importing it ,you have a chance to scale it [ set the cut size ] . It wiil then show up on your table . Click the + icon [ nesting ] to drag it arround where you want the part on your table . Unclick the nesting icon . Now you must set up a cut tool [plasma ] use your plasma cutting machines suggestions for the settings , based on material thickness . Click ok and that part of tool setup is done . Now you must set up an operation , this is where the new cutting tool will know how to cut the part . The layer box is very important , click on it to asign a layer to your part to cut . After the operation is set , save as , then click the post process button . You now have created g code . This file must be transfered to your cutting machines computer .
I highly recommend anyone learning , join the Yahoo Groups for , Sheetcam , Mach , And CandCnc .

01-31-2012, 01:30 AM
cool thank you for the help