DIY Moon Phase Dial

[Gina]

Gear printing...  Initial appearance shows that the teeth produced by mainly X motion are good but at 90° where it's mainly Y motion, the teeth are widened.  I reckon I'm trying to move the Y axis (the print bed) too fast.  The X axis is just the hotend, nozzle and fan etc.

[Pan Euro]

Hopefully you have found the problem, fingers crossed.

Ed

[Gina]

Thanks Ed

I think this printer is looking better than the little UP Plus 2 which has seen better days.  I think I could probably do with a smaller nozzle for the small stuff though.  It's 0.4mm and I think I might try a 0.2mm for printing more accurate things.  I might try this same gear again with slower motion settings.

[Gina]

 Well, the print was a total disaster

[Gina]

The silicone grease has arrived and looks a good consistency - not too stiff

[Gina]

Hmmm...  What now???  I want to get that darned clock working.  Wondering whether to go back to the other gears and try the silicone grease.  One other possibility - I have another 3D printer - the "Titan" - that produces good quality large gears, not so sure about smaller gears.

[Gina]

I've designed a gear pair with 8t and 45t mod 1.77 which looks reasonable and which I think I might try printing.

[Stub Mandrel]

4 hours ago, Gina said:

 Well, the print was a total disaster

Looks tasty :-)

Can't see it keeping good time though. At least it's raised a smile.

[Gina]

Yers...  Thought you might like that

[Gina]

Tried using my Pilot printer but no joy so I tried the UP again.  Not bad and should be alright now that I have been over all the teeth with a rat tail file.  Mesh seems to be alright.  Unfortunately I have another problem - my soldering iron has given up and some motor wires have broken at the circuit board connection, so I can't test it.  I dunno - if it's not one thing it's another

[Stub Mandrel]

One woman's battle against entropy...

[Gina]

I think I have another soldering iron somewhere but where is another matter   I have an iron on order due to arrive tomorrow.  With the amount of electronics I do I really ought to have a spare.  I have had this 25W Antex for more years than I care to count.  Been brilliant

[Stub Mandrel]

In some 35-40 years I got through two 15W CS irons (one still going), but now I have one of the new TCS irons which is a 50-watt CS one with a digital temperature control/readout, which is very good.

[tekkydave]

2 hours ago, Gina said:

I think I have another soldering iron somewhere but where is another matter   I have an iron on order due to arrive tomorrow.  With the amount of electronics I do I really ought to have a spare.  I have had this 25W Antex for more years than I care to count.  Been brilliant

I'm still using an ex-BBC one that was old in the early 90's

 

 

[Gina]

That looks a nice one dave

My new soldering iron arrived this morning and I've soldered the new Hall sensor for the hour hand and the minutes drive motor connections so will be testing shortly.  Stopped for a coffee break ATM.  The iron is a Draper 25W and seems quite adequate thought the mains cable is very short,  Not as nice as the Antex and I expect to order one of those next month when my finances recover.  Car is in for MOT repairs ATM - groan

[tekkydave]

40 minutes ago, Gina said:

 

 

40 minutes ago, Gina said:

That looks a nice one dave

My new soldering iron arrived this morning and I've soldered the new Hall sensor for the hour hand and the minutes drive motor connections so will be testing shortly.  Stopped for a coffee break ATM.  The iron is a Draper 25W and seems quite adequate thought the mains cable is very short,  Not as nice as the Antex and I expect to order one of those next month when my finances recover.  Car is in for MOT repairs ATM - groan

The iron itself is a Weller (always good quality) but the PSU underneath I have never worked out who made those. It's definitely not a Weller. There is a symbol on the front but I havent traced it. It was probably made for the BBC specially - they used to do that sort of thing. The old joke was that the BBC was the best in the world  at putting UK companies out of business :D. Anyway it's still going strong.

[Gina]

Ah yes, we had Weller irons at work many many years ago - very good thery were

[Stub Mandrel]

Don't forget you can get replacement elements for Antex irons

http://www.antex.co.uk/soldering/spares-accessories/replacement-elements/

Should save you a few bucks over a new iron.

[Ajohn]

Gina every time I see the name of a 3D printer mentioned I have a look at it on the web. Is the Titan you mentioned the one that uses a closed loop servo drive ? Price very ouch for me but the construction is interesting.

My Weller is still going strong on it's original supply. It dates from the 70's. Just hope it remains like this.

John

-

[ChrisLX200]

I also have a couple of veteran Weller irons, and a goodly selection of tips - courtesy of when I was last working prior to retirement! I keep one in the Obs for on the spot repairs/mods and one in the house as the workhorse. They must be reliable given their age.

I had to make a repair to my Wanhao 4S 3D printer a few days ago after a ball-bearing failed - really awkward position which required dismantling most of the top end of the printer and X-Y gantries. I didn't have an exact replacement but found a bearing that would fit (8mm ID, 12mm OD) from the stuff I collected after dismantling old hard drives. It's in there and working now. The supplier did send a replacement (eventually) but I wanted the printer back in operation quickly so didn't wait. Really, I should have improved the design to include a pair of bearings as the loading on that component is high - oh well, at least I know how to pull it apart now so if needed it will be a quicker job next time ;-) Overall this printer has been very good, it produces excellent prints and is in constant use.

ChrisH

[Gina]

6 hours ago, Ajohn said:

Gina every time I see the name of a 3D printer mentioned I have a look at it on the web. Is the Titan you mentioned the one that uses a closed loop servo drive ? Price very ouch for me but the construction is interesting.

My Weller is still going strong on it's original supply. It dates from the 70's. Just hope it remains like this.

John

-

The Titan I mentioned is one of mine.  RepRap style with Arduino Mega 256 processor and RAMPS (Shield).  Built in a box 500mm cube with a 300mm square print bed with 24v silicone rubber heater.  Motors arw NEMA 17.  Motion guides are V slot aluminium extrusion with high accuracy wheels to fit.  Motion drive is with ultra strong non stretch fishing line and 3D printed drive drums.  Print bed moves up and down for the Z axis and the X and Y axes control the hotend/nozzle.  Bowden filament feed.

[Gina]

I now have the clock running fine at full speed with the new minutes motor pinion and wheel/gear.  Proper design with plenty of clearance has meant that the gears no longer bind.  I have allowed a millimetre of play between the teeth with teeth about 4mm deep.  The teeth drive well without any tendency to jam.  I have also redesigned and made new seconds gears.

[Stub Mandrel]

That'#s one advantage of involute gears over cycloidal ones, they are very tolerant of the spacing, whereas cycloidal gears like to be spot on.

[Gina]

With the new gears the time is changed more quickly than before with the stepper motor running fast - about 25s to advance the clock by an hour - that's quite a bit better than 70s   Something like 5m for 12 hours.

[Gina]

Now to re-calculate the timings v steps for running the clock normally.  Minutes motor pinion is 8t and minutes wheel 45t. 

Taking the required timing gives the following :-

1. Stepper motor does 2048 steps per revolution. 
2. Minutes wheel does one revolution per hour = 60m = 3600s. 
3. Steps per second = 2048 / 3600 = 128 / 225.
4. In terms of the actual gears this is 16 x 8 and 5 x 45.
5. That's 16 steps every 5s.