Project 1 from EmptyNester. Category: Custom Shop Tools - CNC Table

[posixPilot]

Google sketch up is a good alternative to Visio for this type of drawing, since does dimensional material do well (I.e. lumber, tube, etc.). And it's free to boot!

Cheers
Mike

[EmptyNester]

I finished construction of the basic table. I haven't done the mounts for the rails yet.

It has both wheel and anti-vibration feet on it. This will let me move it around the garage by myself. It's worked well for moving it in and out of the garage.

This picture is while I was draining the table after the water test. Unfortunately, I have some work to do on fixing leaks.



What was interesting is the two leaks in the photo below. If you look closely, where the arrows are pointing, you can see a gap in the heat affected zone. This is just where the leaks are.



For the drain I just used a 1/2" black pipe coupling on the bottom of the water pan and threaded a ball valve on it.

[zoama]

For the drain I just used a 1/2" black pipe coupling on the bottom of the water pan and threaded a ball valve on it.

May as well put a garden hose adapter on it http://www.amazon.com/Anderson-Metal...094267-8385652 (link is only for illustration)
You could fill it the same way... slowly with no fountain.

[EmptyNester]

Zoama,

You've become my idea man! That would work out well for filling and draining.

(I just got the mandrel for my hovercraft muffler. That's was another great idea from you. - Thanks)

[Rambozo]

That is so not what I meant when I said I wanted a pool table.

[EmptyNester]

That is so not what I meant when I said I wanted a pool table.

Unfortunately, its a little leaky as pools go. I went through one round of patching holes but still have some left.

I probably shouldn't have painted it until after I tested. Now I'm not sure how I'll get the paint out of the corner that needs "patched".

[ShaneJackson]

Just get some of that liquid rubber spay they sell on TV. It will fix anything.

[Rambozo]

Unfortunately, its a little leaky as pools go. I went through one round of patching holes but still have some left.

I probably shouldn't have painted it until after I tested. Now I'm not sure how I'll get the paint out of the corner that needs "patched".

This is true. You also don't know if the paint is sealing other very small leaks. When I used to build oil pans, I found that testing for leaks with solvent or mineral spirits is better than water. Less surface tension and it seems to find everything.
I'm sure a little heat and a wire brush will burn the paint out of your corners enough to re-weld them. MIG and stick can be pretty forgiving about bits of paint, at least. Of course just coating with a sealer is the easy way out.

[EmptyNester]

Since I have a sqaure tube frame, I decided to use angle to make an adjustable mount for the gantry rail.

I cut a wood pattern so that I could cut slots in the angle. It would allow bolting the angle to the square tube legs. The slots are vertical so that the entire piece of angle can be moved up and down to level the gantry rails to each other.

At the top of the angle, I put another piece that had a slot in it. This is to allow movement of the gantry rail closer and further in relation to the other side.

[EmptyNester]

When I welded the carriage, I didn't think about the cross tube between the two x-axis.

I ran a weld bead along both the top and bottom of each joint. The top of the top joint is where the y-axis bolts on. The weld bead would have prevented any adjustment in length of the y-axis (it's a slotted plate).



A little bit of grinding and the situation was fixed.

[EmptyNester]

So, I updated the spreadsheet I'm using to track cost with. I think (hope) this will be my final cost. I tried to format it in a table, but all the spacing keeps getting deleted.

The quick summary is:
- my table and electronics $1972 (versus $4305 - purchasing system)
- z-axis and floating head $337
- Mach3 and Sheetcam $325

Grand Total - $2634 (versus $4967 grand total for commerical system)


Here's a breakdown of what I paid for stuff........

Stuff I didn't buy
PC - Had an old one
Case for electronics - Used an older PC case
misc nuts/bolts

Stuff I bought (for a 4' x 6' table)


Precision Plasma Carriage Kit $325.00
Steel Frame $365.00
Steel Water Pan (not stainless) $120.00
McMaster (3) 6' Racks $162.00
McMaster (4) Gears $62.00
McMaster Flex Cable $50.00
McMaster VHB Tape $23.00
McMaster (4) Anti-vib leveling feet $30.00
Table Total $1,137.0

Motor Drive/Electronics Total
Ebay 4 Axis Control (428 oz motors) $407.00
Ebay 5 Volt supply $17.00
Ebay 12 volt power supply $7.00
Ebay Relay card $3.00
ebay Limit Switches (12) $10.00
ebay E-stop switch (4) $16.00
ebay Arduino for THC $24.00
Amazon Terminal strips $14.00
Motor Drive Total $498.00

My Total 4'x6' Table & Electronics $1,972.0

Comparision 4x4 iPlasma w/ stainless pan $2,995.0
C and CNC motors (300 oz) $1,310.0
total w/o Z-axis mechanicals $4,305.0



Additional Stuff you'd buy either way

Z-Axis
McMaster Torch attach collar $7.00
No Sleep Studio Z-axis, floating plate $330.00
Z-axis total $337.00

Software
www.Artsoft.com Mach3 $175.00
sheetcam.com Sheetcam TNG $150.00
Software Total $325.00

[SeanMurphy265]

I would add some support in the middle, but if you not cutting over 1/4" it will probably work fine.

[EmptyNester]

I would add some support in the middle, but if you not cutting over 1/4" it will probably work fine.

I probably won't be doing anything heavy. (I just wouldnt' be able to lift it.) I'm planning on more decorative/artsy stuff.

If you look at post #12 you can see the cross pieces I put in. Would you put in support in addition to that for heaver work?

[SeanMurphy265]

I probably won't be doing anything heavy. (I just wouldnt' be able to lift it.) I'm planning on more decorative/artsy stuff.

If you look at post #12 you can see the cross pieces I put in. Would you put in support in addition to that for heaver work?

I think it depends on how heavy you go! You have your 4 vertical corner tubes now, but if you add one piece of tube in the middle (vertical) on all four sides that would greatly reduce the capacity of the table. My table is heavier 5'x9' and I used 3/16" and 1/8" tubing; I can slide the table fairly well. I'm going to add some castors in the rear to help move the table.

The main thing that would scare me is the the gantry (depending how you mount it). If you get too much weight on the table it could distort your gantry. I have seen where some people have made their gantry where it could stand alone instead of mounting it to the table.

I called precision plasma about their Z axis and they would not sell me one. Since you bought a kit will they sell you a Z axis?

[EmptyNester]

I think it depends on how heavy you go! You have your 4 vertical corner tubes now, but if you add one piece of tube in the middle (vertical) on all four sides that would greatly reduce the capacity of the table. My table is heavier 5'x9' and I used 3/16" and 1/8" tubing; I can slide the table fairly well. I'm going to add some castors in the rear to help move the table.

The main thing that would scare me is the the gantry (depending how you mount it). If you get too much weight on the table it could distort your gantry. I have seen where some people have made their gantry where it could stand alone instead of mounting it to the table.

I called precision plasma about their Z axis and they would not sell me one. Since you bought a kit will they sell you a Z axis?

I had thought about a single leg in the center of the table, but figured that would make wheels much harder. I did figure I could always add legs later and though adding one to the long side of the table would need it first.

I hadn't thought about the weight distorting the gantry. I guess that's something I'll need to keep an eye on.

I didn't pursue buying a z-axis from precision plasma. They seemed too expensive and were beyond my budget. I got one from No Sleep Studio. In hind sight, I may have gone with their gantry kit had I known about them at the time I purchased my kit.

It's funny that they wouldn't sell to you. I had a similar thing happen with C and CNC. I sent him questions about his low cost THC. I figured that was the best for the money. I asked if he had experience with Everlast machines. He told me a Longevity machine blew up one of his boards. He then said that since they are from China and Everlast is from China - I wouldn't get a warranty. After that, he didn't response to email.

As a result of that, I'm going to try using an Arduino board to make a THC. I have the board with a display (about $45) and am adding a prototype board ($12). I think I'll need about $10 to $20 worth of parts. I write embedded control software for a living, so I don't think that will be a challenge. The only hard part will be discovering all the "gotcha's" a THC has to deal with.

So, when I get it "mostly working" - I'll make it open source for anyone who wants to use it.

[EmptyNester]

I cut the slats and put them in the table.



I had orginally put in slots every six inches. When I looked at it, I decided that was too far apart. So, I went to four inch slots. As a result, I didn't have enough steel to fill them all.

I just painted the gantry rail mounts, so I'll be able to mount them and the gantry rails in a couple days.


Question:
I had been thinking of painting the slats with heat resistant paint. Anyone have any experience with that? Is it a good or bad idea?

[EmptyNester]

Got the gantry rail adjusters and gantry rail installed. All the adjustments went well and it was easy to get everything square and level.

[EmptyNester]

Got the gear racks installed. Then did a third water test after using the leveling feet to set the table up. (Y-axis is just siting there, its not finished.)

Leveling feet worked great. Only one small leak left in a corner. I'm not sure if I should use silicone caulking or the spray on rubber sealant. (The leak was in a tube joint and water was going into the frame tube and coming out a pinhole in the bottom weld. I drilled a drain hole in the bottom of the tube so that water wouldn't accumulate.)



Because of concern that I might need additional support in the middle of the table, I took measurements before filling with water and after. There was absolutely no deflection. I didn't have the slats or any material to be cut loaded, but I did overfill it with water. So, I'll probably test it again with slats and steel to be cut, but I'm thinking it will be okay without additional feet.

[EmptyNester]

I have the Precision Plasma carriage kit and the ShopDroids Z-Axis. The mounting holes didn't match.

I had to drill new holes on the carriage. ShopDroids sent me spacers so that the bearing bolt head wasn't an issue.



I also have the touch and go plate, but couldn't install it because I forgot to order the bushings for it.

[SeanMurphy265]

Do you think the Z axis is strong enough for a router? I've thought about making a separate plate with mounts that would hold a dremel for cutting designs from 4x8 sheets of foam.