Smiler's Build

[audioandy]

Jeff

Great looking machine and signs, I have two CNC4PC BOB's and both have been very easy to set up and operated flawlessly so far, as you know I am still in the early stages of getting my machine up and running so they have not been used in anger yet, also Arturo is very helpful and very quick to answer any questions.

Andy

[lateAtNight]

Hey Smiler,
I just put in my order for one of DIY Cnc's BOBs, and I'm a little concerned that you're going with a different make. Was it a user error, or did it give up the ghost on its own? :D. Should I be thinking about canceling my order, and going with someone else?

I really like what you've done...

Dave.

[Smiler]

Hey Smiler,
I just put in my order for one of DIY Cnc's BOBs, and I'm a little concerned that you're going with a different make. Was it a user error, or did it give up the ghost on its own? :D. Should I be thinking about canceling my order, and going with someone else?

I really like what you've done...

Dave.

User error Dave. My main BOB is a DIYCNC Uniport and I'm very pleased with it indeed. Buffered outputs for 4 drivers and three relays onboard that don't need external power. The original one was an Optoport which I shorted out trying to wire in a relay in my hamfisted way. Roy repaired it FOC and I put it back in as Port2 so I could have some extra inputs to Mach. Well, I managed to do the same trick and shorted out the board AGAIN and I just can't face asking Roy to fix it again. It was my own stupid fault "tinkering" when I should have just said "right, that's the controller finished". What I was thinking of doing was just getting an opto-isolated BOB which can use pins 2-9 as inputs as that would be what I really wanted and DIYCNC don't do them or I would be buying one from Roy ASAP.

If you've seen my other post this morning about the U-HID interface, well that would mean I don't actually need another BOB at all and that might be the way I go now.

Don't think you will go wrong with DIYCNC, they are very well made boards.

Regards, Jeff.

[Lee Roberts]

I hear ya....It's grim up north :D

Iii it is nothing but rain and more rain all week and all weekend !

(Wigan)

[irving2008]

Jeff,

That looks really impressive. Some questions & thoughts...

The Y-axis looks like ally box section welded to some end plates, is that the case and if so what did you weld them with? and how did you get them square? The y-Axis supports, are they the thick PVC you mentioned earlier? were they milled to the T-shape for the mounting on the X-axis pillow blocks or is that 2 pieces joined?

Even tho my first MDF build isn't yet complete I'm already planning a ally and/or steel build, poss a 4-axis job that can act as a lathe too...

Instead of energy chain, which is expensive and bulky IMHO, have you considered using a spring pole (think of a bendy fishing rod) and bringing the cables down from above?

[irving2008]

Thanks Jeff ill add that link to the links database now.

Yea i may just give the pvc a go for the little mini mill i wanted to build, ali costing more money ! maybe once i get my rockcliff up and running maybe then ill use ali and get the rockcliff to machine it.

Nice machine Jeff congrats !

I would do a little more research on PVC v Ally or MDF...

Here's some data (MDF/PVC/Alu):

Tensile strength: 0.3/58/300 MPa
Youngs Modulus: 3.6/3/69 GPa
Density: .73/1.44/2.7 kg/m3

The MDF is half the weight and slightly more rigid against bending than PVC but will delaminate far quicker. MDF is also far cheaper than PVC (about 1/25).

Solid aluminium is 20 times more rigid than either MDF or PVC but weighs more (2 x PVC, 5 x MDF) but then it could be 1/5 the thickness of MDF but still 4 times more rigid.

So PVC's main advantage is in areas where the MDF is likely to delaminate under stress... eg where it has to be end-fixed or there is a strong perpendicular force retained purely by the MDF (not bolted through). Its not an obvious replacement in all areas.

The other main advantage of PVC compared to MDF is that it is available in a range of thicknesses up to 50mm.

I would potentially use PVC for:

• The table, where you want to machine the surface flat and avoid flaking.
• The gantry sides where I could use 40mm thick PVC and get twice the rigidity of MDF (then again I could use 2 pieces MDF bolted/glued together to get the same result at 1/2 the weight and 1/10 the cost)

[Gary]

I think you will find that the Y axis is steel painted silver not ally?

Jeff,

That looks really impressive. Some questions & thoughts...

The Y-axis looks like ally box section welded to some end plates, is that the case and if so what did you weld them with? and how did you get them square? The y-Axis supports, are they the thick PVC you mentioned earlier? were they milled to the T-shape for the mounting on the X-axis pillow blocks or is that 2 pieces joined?

Even tho my first MDF build isn't yet complete I'm already planning a ally and/or steel build, poss a 4-axis job that can act as a lathe too...

Instead of energy chain, which is expensive and bulky IMHO, have you considered using a spring pole (think of a bendy fishing rod) and bringing the cables down from above?

[Smiler]

Jeff,

That looks really impressive. Some questions & thoughts...

The Y-axis looks like ally box section welded to some end plates, is that the case and if so what did you weld them with? and how did you get them square? The y-Axis supports, are they the thick PVC you mentioned earlier? were they milled to the T-shape for the mounting on the X-axis pillow blocks or is that 2 pieces joined?

Even tho my first MDF build isn't yet complete I'm already planning a ally and/or steel build, poss a 4-axis job that can act as a lathe too...

Instead of energy chain, which is expensive and bulky IMHO, have you considered using a spring pole (think of a bendy fishing rod) and bringing the cables down from above?

Hi Irving,

The frame of the router is steel box section welded to plates which are then bolted to the PVC ends. To keep things square I started with a flat surface, in this case an old RSJ I borrowed from work. I clamped a largish vee block to one end and clamped my end plate vertically to it. Next I clamp the box sections down to the RSJ with a space at each end to ensure parallel. The end plate is then tacked to the box section. I leave the box sections clamped down and move the vee block to the other end of the RSJ, clamp the other endplate to it and repeat. Once I have both ends tacked, I weld the plates in position. After that I check the diagonals and adjust if needed to bring it back to square.

I never get hung up on getting a small fabrication like this super square before fully welding. It's pointless as the welding will pull your corners in. Keep all your welding balanced i.e. if you weld one side of the box section, weld the other side too, I only welded the two vertical sides, welding all three would be overkill and introduce warping that is not easy to get out. Do the absolute minimum welding necessary.

If I had decided to do the gantry in Aluminium I would have used our Dual Pulsed MIG at work, faling that TIG would have been my next preference. My frame looks like Aluminium because I sprayed it with AluZinK cold glavanising spray to protect it while the build continues :)

The PVC end plates are in fact two pieces, the bottom piece is bolted into the vertical one (6 X M8 socket heads). I just cut them with my table saw (slowly) and then planed them on my 10" planer. As long as you treat it as very hard wood and take small cuts and slowly, you could be using MDF but of course it is a much superior material (IMO:)). I am very pleased at how it has worked with the steel frame.

Re: your idea of a spring pole, THAT'S A REALLY NEAT IDEA :D. I have two joists above the machine which I could mount it on and the controller could live up there out of the way of the dust too. Thanks for the idea, I'll set it up and post some pics :)

Thanks for the input Irving, much appreciated.

[Smiler]

I think you will find that the Y axis is steel painted silver not ally?

Spot on.

Gary, it must give you a buzz seeing the bits you supply fitted to actual working machines. Thanks for bringing down the cost to the level that Joe public can get in on such a fascinating hobby!

[irving2008]

Hi Irving,

The frame of the router is steel box section welded to plates ...

ah.... are RSJ's that flat then? I was wondering about getting something flat to work on... I have my eye on a granite worktop I have seen in a skip nearby (some people have more money then sense), but I have no idea if I could lift it out and get it home.

The PVC end plates are in fact two pieces, the bottom piece is bolted into the vertical one (6 X M8 socket heads). I just cut them with my table saw (slowly) and then planed them on my 10" planer. As long as you treat it as very hard wood and take small cuts and slowly, you could be using MDF but of course it is a much superior material (IMO:)). I am very pleased at how it has worked with the steel frame....

Table saw, planer???... wish I had the space for these, best I can do is a cheap Skil jigsaw and a B&Q circular saw... and a hand planer :D

Re: your idea of a spring pole, THAT'S A REALLY NEAT IDEA :D. I have two joists above the machine which I could mount it on and the controller could live up there out of the way of the dust too. Thanks for the idea, I'll set it up and post some pics :)

Thanks for the input Irving, much appreciated.

You're welcome Jeff, I have used something similar in the past, two sections of 16mm dia tubing joined by a old door return spring. Cables ran inside some square section lidded 16mm trunking screwed to tubes with a spiral wrapped loop at the spring junction. Look forward to the pics