RC Tank Warfare community hobby forum

wibblywobbly wrote:I am printing all of the parts designed so far, while I wait for the suspension springs to arrive, as I need to check where the mounts are on the lower hull, to get the correct tension.

Yes, the parts are turning out well, though I am always aware that they could be even better if I applied myself to some minor details on the configuration side of things. The printer is positively ancient by current standards, but as it does the job, I am not complaining.

Looks impressive, Wibb...as ever. Are these examples printed with PLA? In the Ad for my Hictop, it suggests that it's an ABS capable printer. With a bit of digging, I found that an upgrade could be bought to make it ABS capable...I think. That said, I'm so busy with other stuff that I've not even switched it on yet for the first time It was a Birthday/Christmas/Birthday present from my Son.

All printers can print in either ABS or PLA. If you use ABS you have to use the printed bed, but with PLA you can print on a glass bed, I use a £1 Ikea mirror and hairspray.

The nozzle diameter is important, some ABS printers use 3mm filament, PLA is 1.75mm, but they can be swapped in minutes.

I can't believe you have a printer and haven't switched it on yet? I think thats the same one that Alwyn has, and apart from a few minor set-up niggles he gets excellent results.

This lad makes very entertaining and informative videos on 3D printers.

Literally just logged in to read it between prints, many thanks, I will design a box with those dimensions and then see if it fits without sticking into the upper hull, this tank has very little space at the front due to how high the shafts are, HL boxes won't fit at all.

I wish I knew how to design gearboxes!!

Many thanks!

PLA is as tough as old boots, I run plastic gearboxes in a few of my tanks without any problems, so my guess is that if I can print the gearboxes they will be good to go. Any such fantasy is a long way off though, but I will have to give it go sometime just to see. There are guys on the interweb who have printed the transmission for RC rock crawlers and gears for all sorts of models, so it has to be worth a try. If I could print low ratio gearboxes in PLA I would be over the moon.

Hi Rob, this is just a wild thought but couldn't you take an existing gearbox and strip it, and reorganise the gears so they would fit a printed box, you could use bearings to prevent the gears ripping the box to pieces? With this approach if you can lay out the gears differently to suite the space available, it might fit?

Alwyn

Alwyn, you have far too much faith in my abilities, lol. I understand what you are saying, and yes, I was thinking that the bearings would be needed, but as to what gears would need to be where in order to change the ratio...I haven't got a clue. One approach would be to take a 2D scan of each gear, and the same with the cases, load the jpg files into Cura, save the STL file, import the STL's into Openscad, and then extrude the gears and cases to the required thickness. That way I would have a copy of an HL gearbox. It would then be fairly simple to move the gear shafts in arcs to get low profile boxes, or insert another shaft/gear.

I may give it a go when I have done with printing everything on this model.

I just got 3 hours into printing the crew surround, and was so busy looking on here I never noticed that the nozzle had blocked...aaaarghhh! It's a 6 hour print, so back to square one and start again!! It was printing the wafer thin support structure that did it, hope it doesn't happen again..might try installing my own supports and disabling the Cura option.

Speaking of printer issues I have just spent 3 days fighting my printer, and just couldn't get it to extrude properly, and finally got a message - heating failure. Basically the hot end was dying and has given me weeks of hassle in the process. Luckily I had bought a spare hotend so fitted it and dammit the prints were perfect. If I had only changed the hotend 2 weeks ago I could have saved myself no end of frustration and failed prints!!!!

Oh well so long as I got a happy ending I shouldn't complain but sometimes this 3d printing really sucks!

Alwyn

Hi Rob actually looking at the KV1 heng long gearbox, you wouldn't need to change the ratios, just lay the existing gears out in a straight line instead of up and down as they have them, and also these is some spare space in the bottom of the box, and you could save a good 15 to 20mms in height, and you could also set your dive shaft at whatever height you chose. The heng long box also has nylon bushes so you wouldn't need bearings.

Just a thought

Alwyn

A hotend can't fail....only three things can happen,

1. Nozzle blocked
2. Thermistor failure
3. Heating element failure

1. The hotend has to be taken apart, the nozzle cleared with a blowtorch and 0.4mm drill until you can see daylight through the nozzle.
2. Check the thermistor 2 pin plug on the Ramps board, if that is not loose, then replace the thermistor. They cost pennies on Ebay.
3. If the thermistor is not working then the element won't heat up. If the thermistor is working then check the heating element wires on the Ramps board. If they are ok, then check the wiring on the element itself, they don't last forever, the wires break right on the joint where they go into the brass ferrule.

I keep a bag of thermistors and heaters as they pack in due to the extreme temperatures they operate in.

Son of a gun-ner wrote:Well, we learn something new every day, and because I know squat about 3D printing, I had no idea you could print strong enough gears.

A gear train is a bit like pulley wheels for lifting heavy objects. Yes, I know motors also rev at a high rate, but the motors we use probably wouldn't have the guts to move heavy tanks directly, so our gearboxes serve two purposes, reduce the speed of the motor, and provide the torque at the cogs.

Mick.

There are 3D printed gearboxes lifting anvils and cars on You Tube.