Dadio's 3D Printing Stuff

[Dadio]

Now that the Dogfighter project is in its final stages i started working on some Zerda parts , firstly some rear body side panels , these just clip on and are made from nylon and secondly a part that often breaks , the front bulkhead , they tend to shear off the front suspension mounting point , the later Alien mid had a much beefier part but requires longer mounting pins that are unobtainable .




the bulkhead is a very fast test print only for checking dimensional accuracy , i think I've got it right now so I'm printing a better test piece now .
Not sure how far I'll go with Zerda parts but i will do a beefier steering knuckle as they are a weak spot too .

[Dadio]

Been gettin festive so i drew these simple Tree decorations up and printed them.

[Dadio]

Ran this off as i thought the ones on the market were overpriced , its a top spring collar for Tamiya SRB 8mm body shocks so you can convert to coil springs .



Secures with a single Set screw ,designed for 10mm internal diameter springs , it works in PLA as long as your gentle with the threads , should be fine in other filaments , its on Thingiverse if anybody wants to try them.

[Dadio]

I was asked if i could make an improved steering knuckle for the Hirobo Zerda , they are a weakness and i had one brake myself , i managed to get a pair of knuckles for the Alien Mid that are stronger but hard to find so these are the ones i came up with , the red one on the right is a Zerda original , in the middle is the Alien Mid and mine is on the left .

[ROH73]

That looks quite stout; nice job. What's the material? Carbon Nylon?

[Dadio]

yup carbon nylon , ill pop it on thingiverse later

[Dadio]

The Zerda knuckle is now a free download on Thingiverse or it will be when they get round to it

[Dadio]

It finally arrived ! A box full of Creality LD-002R goodness (well acceptable quality for a reasonable price as usual) , its surprisingly small when your used to FDM printers ! it came well packaged and seems very sturdy , very quick to set up and she's printing a 19 hour Eiffel Tower already , much less interesting to watch than an FDM , all the action is submerged in resin and at first nothing seems to happen as the bottom layers take 50 seconds ,so you wait nearly a minute it then raises and lowers (but not clear of the resin ) and you wait again , after the bottom layers (5-8) it goes to 8 second layers , in short its going to be pretty boring for the first hour or two till the print starts to emerge from the resin.
I'm using Siraya tech Fast ABS like grey resin , not totally stinky , much less smelly than fibre glass resins or body filler for example but its not a nice smell either so the whole kit and caboodle will live in the workshop .
Anyway not much more to say till tomorrow when the Froggy scaffolding is finished .

[Dadio]

Well the print finished but even last night i could see a fault , there's a hand rail on the first viewing level and the vertical struts are virtually the thickness of a hair ! and thats the failure point ,the hand rail is distorted and barely attached, watching YouTube of unboxing's this seems about normal , the rest of the print is outstanding though , you can see daylight through the cross struts to nearly the top ! layer lines are really hard to see at all .





very pleased so far .

[Dadio]

Printing some yokomo 834b gears now to see if they are strong enough .

[Dadio]

Here's how the gears turned out , firstly there is one small blemish , there's a swell in the width of the gear teeth and a slight narrowing either side , it doesn't seem to affect the mesh and its almost certainly because i angled the gears on the bed so i could fit them all in , so printing them flat should solve the problem , other than that they seem flawless however these were designed for FDM printing not resin and with FDM holes tend to print under size to you enlarge them by design knowing they will shrink in printing , i'm expecting all the axle holes to be too big but i don't have time this morning to check .The material feels very promising , i can flex the gears a little and this resin is meant to be "ABS like " , they honestly feel like a moulded part . The settings i changed were exposure time down to 6 seconds from 8 and much finer supports , both seem to have worked really well and the supports just peeled off in a very satisfying way leaving just a lightly dimpled finish .
Just after completion still hanging from the bed.

Straight from washing and removing from supports .

After final curing in the UV light box


Not too clear bit this is the defect from printing on an angle .

[threesheds]

The Eiffel tower print reminded me of Alec Guiness in the lavender hill mob..

[Dadio]

The gears fitted the 5mm axles better than i expected , in time i'll make them a tighter fit but for now they are good enough to test , i fitted them to one of my spare 3d printed yz-834b gearbox's and the mesh is good , better than i expected so I've built up the gearbox and installed it in the Yo-Clone-Oh , its pitch dark now but I'll test it tomorrow , not sure what to expect really but probably 2-3 min then failure

[Dadio]

Well predictably the resin gears failed , i got 5 min out of them , the failure point was at the distorted section where it didn't mesh as closely , although there was damage to all the gears i think it was the debris from the first gear driven by the pinion that caused the damage further down the gear train , the first gear failed loosing nine teeth off its larger section and no damage to the smaller gear , the second lost only one tooth , third gear only a chip off one tooth and the diff gear lost an even smaller chip off just one tooth . this pattern of damage looks promising , if i reprint the gears flat rather than at an angle to the bed then the distortion should vanish giving a truer mesh and no weak point , ultimately i'm not expecting the first gear to survive and it may have to remain a CF nylon gear but i feel that there is a possible advantage for the other gears , the diff gear is hard to print cleanly in CF nylon and the second gear is awkward where the drive pin goes through to drive the chain , so i'll have another go .

[Dadio]

New gears printed and fitted , once again its dark out so I'll wait till morning to strip the teeth off them I do have another resin coming to try as well .