Machining Aluminum #122 - Sydney, Australia

[KenC]

Its easy to forget the fan will fail sometime.
I would try to place air intake low & outlet high& my hottest components between so that when the fan fail, warm (light) air will still flow out of the casing & suck in fresh cool air at the same time.
The alternative is to have an externally mounted heat-sink.
Both approaches has their pro & cons.

[racedirector]

Hi Ken

That is exactly how I will have the control box fan positioned, the intake will be on the lower left side (where the fan and filter will be attached) and the outlet will be on the upper right side (with a filter only). All I have to do is get up the nerves to start cutting holes in my control box

Cheers

[racedirector]

A little more progress.... gantry now riding on the shiny black rails. Next task is to take the gantry back off again (! ) and do the whole levelling of the rails via shims.

BTW, I can't seem to find it in the plans but is there a distance measurement between the Y rails like there is for the X, the one that specifies Y axis +461?

Cheers

[KenC]

the final dimension will not be exact match with the drawings. Over the course of building, you ought to have some tolerances/error accumulated. The design allows to adjust the actual W-wheel distance adjust by shimming washers at the mating face between the gantry & concentric/eccentric bush. Its more practical to align & shim your rails 1st & shim the W-wheel to suit.

[racedirector]

Ah, so it is suck it and see My X rails are close to the +461 bit, will eyeball the Y's and go from there....

[racedirector]

More painting completed today and a little control box work done. I *think* I can see an end as the myriad of things slowly diminish Just need to find a seller of John Guest tubing for the spindle and I am pretty sure the majority of spend for majorish things will be over.

[racedirector]

Today was a milestone for me, things being put back on the machine permanently. X & Y rails are all shimmed and locked in place, gantry rides perfectly along the X staying even all the way. The table is level in all directions and the gantry is also level (all directions) on top of the table meaning I have actually done something right Just working on the Y car getting that spot on, running straight and level, not far off leaving that right where it is and attaching more to it. I am really enjoying this stage, it means I am ever closer to making dust!!!

Cheers

[pblackburn]

Which is a great feeling.

[Rapid]

So is it time to place bets on which number you will get

[racedirector]

Obligatory progress pics.... shim waste and the machine so far.....

[darren salyer]

Looking Good.

[Fox]

getting there ! There must be a summer filled with new MM's coming up. Mine looks roughly the same minus paint and with different a Z.

[Rapid]

I like your coffee table also

[Tokamak]

I keep mine filled with stuff too, it keeps the dust from settling on the spoil board. I like the red! You are really close to making dust.

[Rapid]

That is a sharp looking machine ... and since you are the racedirector a nice checkered flag decal on the machine would look good and be appropriate since you are about to cross over the finish line.

[KenC]

Originally Posted by Tokamak

I keep mine filled with stuff too, it keeps the dust from settling on the spoil board.....

Why did not I think of this excuse

[racedirector]

Thanks guys, appreciate the comments. John, I just love the excuse re the spoilboard

Bit of a setback yesterday. Went to check the fitting of my racks on the X and found the rails are canted over as the PFC top is definitely not parallel or flat across the whole 75mm span. Had to work today so nothing done about it but it seems I will need to shim them flat like John did with his. There may be another way if my tests are successful. I thought about buying some 75x6 square edged flat and screwing that to the top of the PFC taking advantage of what flat surface there is on the top. That would give me a flat surface to bolt the angle onto. I have to pull both rails off and do some better measurements to get a better idea of the task at hand so no decisions just yet.

[racedirector]

Jacked up the gantry and put it on axle stands then removed the rails. Measuring a large, heavy, straight steel tube across both beams I deduced it needs .80 mm packing under the outer edge of the rails. The tops of the PFC are infact flat, it is a slight cant in the PFC which is causing grief. Tomorrow (too much wine right now!) I will try and remove the cant on the PFC, if I can't I will try the ole coke can spacer trick to get the rails flat.

[Tokamak]

Sorry to hear about the extra bit of work on your rails, angles are always tough to shim. One option I have seen is to use plastic body filler (bondo). Skim coat the low spots then drag a straight edge across both rails. Perfectly flat. Good Luck.

[smreish]

The car body filler like John described is a very good solution.
I allows for you to "screed" the to top edges like a concrete poured driveway.
I had similar issues too on my #5. But, since I was a bolt together frame, I was able to add shims to the end gates that make up the base table and adjust the "TOE" of the table like a car alignment by rotating the bottom of the beams in my shortening the spanning member on the bottom chord of the end gate.

Like this.

\----/
/----\

Until my two top planes were flat to each other.

Good luck
Sean

[racedirector]

John, that is a brilliant idea. Will go grab some filler tomorrow and give it a go. We have a holiday weekend here in Aus so a day or so of drying should see me putting things back together by Monday. I'll report back how things go

Edit: Sean, just saw your post after I replied to John. I too have a bolted base and will probably try your solution first. The only possible downside of this method is that my holes for the cross members may not be in the right place once done but I will try and cater for that as I go. I originally had the beams bolted to the legs but decided to weld them instead, I am regretting that now.

[smreish]

The cross bearer table holes are the pivot....They should work perfectly. Or maybe have to upsize from 13mm to 14mm to accommodate the drift angle.

I had the legs welded to my sides too.....just the end gates and cross bearer bolted.

Good luck.
Sean

[racedirector]

Of course, silly me. Time to clear things from under the beasty (4 sheets of 18mm MDF) and get unbolting in the morning. Thanks for the good luck, I'll need it

[racedirector]

Well, I must have got the worst possible pieces of PFC in Sydney because PFC they are not. After a discussion with my wife I have decided to fully weld the base giving me a chance to perfectly match the base cross beams and ladder sections to the horrible state of the PFC. Due to its shape the base ladder sections will pretty much be parallelograms just so I can get the tops of my PFC flat. I went out and bought some new 50x50 box for the task and am now setting things up ready to go. I'll spend a bit of time welding up all the holes that will be left first and then get cutting. The only down side is that I will need wheels now and if need to move it I will need a car trailer or flatbed tow truck.

These things are definitely sent to try us but I want my machine to be the best I can get it.

Cheers

[pblackburn]

Bruce I am not so sure I understand what you are experiencing. If it is the C channel is not flat from side X to side B and it tips one way or the other. I used set screws at each bolt down location of the X rail and B rail to fix it. You can see it on my thread here

[racedirector]

Hi Pete

The PFC I got here seems to have both short faces more than 90 degrees from the large face. If I put a square hard up against the "bottom" of the channel both legs are canted inwards so if I sit it flat on one of the legs the whole section leans inward. I was seriously considering finding better channel or going with an I beam instead but my finances argued otherwise. Besides, what the heck would I do with 2 3m pieces of non PFC channel

Your solution seems like a brilliant one, just checked out the post. Mine would be closer to the angle if I had not done anything with my machine meaning the C channel top was sloping to left if looking at the end at 0,0. At this point I have both tops flat in relation to each other, checked by placing my 2m level across them and not seeing daylight/torch light under the edges sitting on top of the channel. This has translated to a 7mm difference in width between the top of the legs and the bottom. Based on this I don't hold much faith in being able to pull it apart and put it back together without alot of grief so welding is my next best solution.

[pblackburn]

Understood

[racedirector]

Do you ever have those times where you can only see the worst possible scenario and then move towards fixing that only to figure out there was an easier way? Well guess what I have done?

I spent yesterday and today pulling the machine entirely apart and resetting things up for the (to me) mammoth task of remaking the base ladders joining the sides together. I pulled the base spoilboard off and drilled the end holes in the cross beams bigger to allow adjustment. I bought more steel to make all the changes including a 75x50x4mm length to clamp to the tops of the beams to keep them flat, all up another $120.00 worth of steel.

I have just returned from the garage after sitting there staring at the mess and realising that I could do it a far easier way. There are only a total of 6 welds per main beam and it would simply be a case of grinding those welds off to reset the beams only. I will bolt the old ladders back in, square up the lower section and then reposition the main beams, complete with the tops nice and flat for the angle, and weld them back on again. Instead of the fix taking all day and probably tomorrow I can have the machine all ready to go sooner including touching up all the paint I have barked off in the process.

[pblackburn]

Sometimes pushing the desired result inhibits clear thinking. I am glad you found a solution.

[racedirector]

Well, my revised method has worked, ground/cut the welds off the leg/beam combo and resituated the beams. I actually have them back in the original bolt positions that I started with (!!) and the tops are now firmly held flat with 2 beams of 75x50x4 box section. I have put the bolts back in and will now tack weld the beams back onto to the legs.

I also squared everything up again and now have it square within 0.5mm. Coffee break right now and then off to tack weld, clean and repaint the missing paint bits.