[epineh]

OK, enough talking about it, here is the log of my machine. Firstly why am I building a router ? Well, the original answer was to make timber fishing lures, I have been looking at making lures for some time, nothing like catching a fish on something you have made. Checked out plastic moulding - didn't like the idea of playing with all those chemicals. Decided on timber, looked at carving one at a time, then thought about what happens to lures, they get bitten by large fish with very sharp teeth, I needed a steady supply - hence the CNC router.

I live in a very wet part of the world, unfortunately this means that a JGRO style machine is out of the question, the humidity hovers around the 90% mark for a lot of the year, wont do much for the MDF. Decided to use steel as a frame, with ideas from the JGRO design incorporated - skate bearings, bolt on rail holders with bolts to adjust rails.

Now I must point out that machining isn't my trade, I am an electrician/data tech, so please allow for that when you take a look at the pictures.

My main thought process is to make a fairly rigid base, use acme thread initially, then if/when it gets going, look at upgrading the screws later on. Remember that I am only looking at making lures, from what I have read, this setup will do fine for that. Later on I will probably get inspired to make other stuff with the machine. I also want to keep the framework as simple as possible, uncluttered but strong.

I made the base out of 100mm by 50mm C shaped Channel, cut to length then welded together to form a rectangle. Gangtry is fixed, to help with rigidity. At the moment thats as far as I have gotten, I am using 40mm solid bright steel bar as x axis rails, 30mm for y axis, and not too sure about z yet. I intend to support the x-rails in the middle point, thinking of a triangular shaped bracket bolted onto the channel and onto the rail itself somehow to provide support, can I drill and tap the bar without weakening it too much? Thought about an 8mm hole drilled/tapped into the bar to fix to the supporting bracket, probably only half the depth of the bar. Any comments on this would be appreciated.

I am putting the skates on the inside pushing out btw.

Now for some pics...
:cheers:


Russell.

[epineh]

Oh yeah, I have built the stepper constant current supplies, pc interface and stepper control boards, mounted them in an old pc tower, am waiting on getting some plugs and sockets to mount on the back for the leads to the machine.

Frame size is 1200mm by 900mm outside measurements.

Russell.

[diarmaid]

Nice. Looks strong. I guess as an electrician you find the part easiest that I think I'd find hardest!

[Jason Marsha]

Good Start, now build like crazy until you collapse and don't forget to keep the pics coming.

Jason

[txcowdog]

That is one sturdy machine considering the size. Definately would withstand a nuclear blast.

[CJL5585]

Russell,

Just one comment.

Keep in mind that everything NEEDS to be EXACTLY square and parallel when building your machine. One might not think that a few thousands of an inch does not matter in construction, but any errors in measurement will show up in a completed machine.

.

[epineh]

Thanks for the comments guys, being a sparky helped with the electronics and power supply stuff, the rest I am a fish outta water (no pun intended!).

I will keep plodding away now I have something started, dunno about till I collapse ;p

I wanted to make the machine sturdy, I made a wood lathe out of steel modular type brackets (cable tray framing) and it was very unstable and wobbly, didn't want to go there again. (wasn't too upset when the cyclone obliterated it ... haha)

As for square, just tryin my best to get everything right, using adjustable rail holders should help with the fine tuning, so long as any error is within limits it should be OK.

Well I'm off to do a bit more...

Russell.

[epineh]

Well, I did manage to add some bracing on the gantry today, not much I know but at least I did something...

The angle is 50mm by 50mm 5mm thick, is a bit old and rusty/dirty as you can see, but nothing some wire brushing and cold gal wont fix, besides it was free.

:banana:

I know the angle is going to interfere with the horizontal bolts on the top rail, my plan is to drill a 23mm hole through the angle to allow for bolt head/socket, hopefully won't weaken the angle too much, should be OK, it is just to provide a bit extra rigidity, coupled with the rails being fixed should tie in nicely.

Russell.

[chich2]

Epineh,
Looks great bloke. That should be a nice rigid machine. Once it's all adjusted and square then either dowel the bolted joints together or give them a quick tack with the welder.

Chich :cheers:

[epineh]

Priced some energy chain today, thought it might look good on the y axis cabling, but at the price, a small length of loom tube or similiar is lookin pretty good *ouch
Might try making some once the machine is up and running.

Russell.

[epineh]

Did a little more today, finished the y axis rail holders and bolted them in place. Holders are built from 62mm steel bar, about 18mm thick.Have taken the top braces out to make it easier to work on the y axis, will bolt them in towards the end of the build.

My father in law is building the x axis rail holders for me, out of 90mm by 20mm bar, he has a small metal lathe so he is turning the 2 inch hole in the middle for me, thanks Sam :cheers:

My son's 4th birthday tommorrow, going on the kuranda train, little fella is mad about trains, loves steam especially, but will be more than happy with a trip in a diesel. Not much going to happen on the router this weekend...

Managed to do a bit of cabling on the control side of things last night as well.

Russell.

[chich2]

Very Nice Russ,
Keep up the good work.

Chich

[epineh]

Thanks Chich, got the blocks from Sam, just gotta drill mounting holes and drill / tap alignment holes, mount them then its onto the sliding part of the x axis (are we there yet ?)

Some days the build seems to drag on but I am enjoying the time spent working on the machine... at least it is taking shape these days

Russell.

[epineh]

Did some more on the electronics side of things today, mounted and connected the constant current supplies and tidied things up a bit.

Added two 12V lighting type transformers (wire wound not electronic) in series feeding a bridge rectifier as a temporary power supply (had them lying around), might use this setup for initial testing but I am limited to 4amps with these (50W), dont know what I will need for the final current output as I haven't decided on what size steppers I am using yet.

[epineh]

Don't know if anyone is interested in a little visual explanation of AC to DC conversion, but here are a few pics of my setup through a scope.

Firstly the one showing 26.91 Volts AC, this is the output directly from the series connected transformers (still AC)

Next photo is at the output of the bridge rectifier, showing 11.88 Volts AC and in smaller writing 24.03 Volts DC, notice how the bottom half of the waveform is "flipped" up to the top half. Although this waveform is "alternating" it is now considered as DC - direct current, as any current flow will be in the one direction, all that is needed is a capacitor to smooth things out a bit.

Now the last photo is a little misleading, I have placed a capacitor across the output of the bridge rectifier, it is only a 2200 uF electrolytic (all I could find )see how the output is now reading 0 Volts AC and 36.82 Volts DC. In actual fact once a load is applied this DC value will drop, dependent on the size of the capacitor used, I don't have any decent load to show this effect, and the waveform will have a slight drop in between "peaks" of the original waveform.

Please remember this is a basic explanation, I thought someone might get a slightly better understanding of AC to DC conversion by having a "look" at what is happening.

Oh yeah, in case you are wondering about the voltages not adding up i.e. 12V plus 12V = 36.82 ? simply put the 12V is AC, and although as far as a simple lamp is concerned it has the same driving force as a 12 V battery. In actual fact the peak voltage goes higher than 12V, the 12V value is considered the RMS value (root mean square) or average (not technically right but will do for the purposes of this discussion)

I tried to keep this as simple as possible, sorry if I managed to confuse anybody and also for the long winded post.

Russell.

[chich2]

Holy smokes Russ. The capacitor smoothed it out HEAPS!!!!! Full on! Very Cool Dude!!!

[epineh]

Thanks Chich, I will get a decent load to show what shape the waveform takes, it will never end up as flat as that, but the cap will fill in the "valleys" to an extent.

Next is the x axis to finish, rail holders are made, have one pair bolted onto the machine, next pair maybe tommorrow then its onto the sliding assembly, got the skate bearings in my head, just trying to work out what to make the bed out of, size will be 600mm by about 790mm, would like to use t slotted steel (everything else is steel so far) but I am worried about the weight.

My thoughts at the moment are to use some 25mm formply I have lying around, it is a hardwood ply with very smooth finish, lot lighter than steel, probably strong enough for what I am doing (timber lures). I can always unbolt it at a later stage if it isn't rigid enough. Of course I would brace it with a 25mm square box section steel frame on all 4 sides, probably with a 3mm or larger wall thickness, welded of course

Built a timber frame to support the machine, it has outgrown the clothes folding table it was sitting on (surprised it was allowed to stay there THIS long) (chair)

Yes thats the wife with the chair...

Russell.

[ahren]

Epineh, your machine is looking good! You mentioned earlier that E-chain is too expensive, but that you'd like some for your machine. I have some going for $30/4 meters in the classifieds section if you're interested. Sorry for the shameless pitch, but I figured you might be interested.

Ahren

[epineh]

Thanks for the comments Ahren, and the shameless sales pitch, you don't happen to sell used cars do you ?... just kidding, PM me with the details, size, postage etc to Australia and I think you have yourself a buyer, 4m is way more than I need, with a fixed overhead gantry it is only for the z axis and a few limit/homing switches, but I guess I'll have it for the next machine.

Cheers.

:cheers:

Russell.

[snooper]

Hey there Russell!

Great looking machine you've got there! I'm planning something similar, and I'm curious as to how you protect the rails from corrosion?

I assume your bearings run directly on the rails; how did you mount them? (Sorry if I missed it...)

Keep up the great work!