Oshkosh 6x6 truck build

[wibblywobbly]

I decided to give the printer a clean just before I sent the new filament back, took the extruder apart and pulled out the filament from that end, and then pulled the other end of the feed tube...hmmm...that's not as long as it should be. I then discover an invisible length of filament halfway down the ptfe tube that would only come out with some persuasion. It was obviously this sticking filament that was causing the problems. Assembled the printer again and reprinted the radiator that had caused the problem in the first place.

This was pulled straight off the printer with no filing or sanding, it is as if it was injection moulded. Woohoo!! Now I can print the other bits that I have queued up.

[AlwynTurner]

Great news Rob, It's always the silly unexpected things that go wrong and take the longest to analyse and fix. Following along. Alwyn

[wibblywobbly]

Seeing as the print quality has improved, I re-printed the exhaust with a different design, offset rows of holes, which is a bit more realistic. Took about 7 hours, but it came out well. You can see a line where I ramped up the print speed, but its only a minor glitch.

[971wright]

Hi Rob I like the stuff you have printed ,I am going to look into getting a printer for doing bits ,they look 10x better than something scratch built.

regards pete

have you any recommendations for the printer needs to be quiet or the boss will do here nut (might have to make a box to put over it)

[wibblywobbly]

It's not the printing that is difficult (once it is set up properly - the web is littered with forums and posts on 'my printer won't print'), it is designing the parts. The best advice that I can give you is to download a few 3D design tools that will export in STL format, eg Openscad, Blender or whatever, and see if you can design parts. Start off with simple cubes and cylinders, and then work out how to merge and/or subtract different shapes to make the ones that you want. It will be incredibly frustrating at first, but there are loads of videos on You Tube for Openscad, and lots of help and advice on the web. Different people find different software easy to use. Blender is a very powerful design tool, but I having started out with Openscad, I can't be bothered to go through another learning curve with Blender. I would be totally lost if someone told me to produce in Blender what I can do with Openscad.

I have a slight advantage in that I already understood the logic behind programming before I used Openscad. However, it was still a long haul to figure out how to create the model parts that I wanted, as long as you aren't expecting to buy a printer and start printing complex items for a few weeks, you should be ok. Blender on the other hand is graphics based, you move parts around on the screen, stretch and reshape them with the mouse etc. I just happen to have a brain that prefers to look at figures and change them.

If someone has CAD experience they would find the whole thing a complete doddle...but I don't have any at all!

As for noise, my printer is in the lounge and it prints away quite happily with nothing more than a quiet hum, which is the two stepper motors moving the base and the print head. I can leave it running while I watch tv etc, and when I go to bed, I don't even notice it until it stops at the end of a print job. If you set it up in a spare room you wouldn't even know it was printing. PLA doesn't smell when printing, however ABS needs to be printed in a closed cabinet on a heated bed, and it does apparently give off an odour. Never used ABS so I can't comment on whether it is intrusive or not.

When I started out, Woz was demonstrating his printing, so I designed a very small part in Openscad, saved the file and asked him if he could print it. This turned out ok, so it gave me the confidence to try buying a printer. I bought the kit, assembled it, hit a few problems with a rare faulty part, but since then it has just been refining settings until I can get the best quality I can. At this moment in time, I don't think I could get it better than it is now. The parts are coming out with smooth sides, no ripples, no holes, no delaminating etc.

[wibblywobbly]

I would also add that some of the commercial printer manufacturers are hitting financial problems, check their background before buying. With a reprap based printer the parts will always be available. They may not look all shiny and neat, but they do the same job. Some commercial printers require specialised filament cartridges instead of a £12 a kilo reel off Ebay?

http://3dprint.com/80760/stratasys-class-action/

http://hackaday.com/2015/10/09/makerbot ... -6-months/

[971wright]

Hi Rob My 6x6 has just arrived ,boy its big your photos don't show how big your truck is ,think you should take a photo of it next to a Tank show the guys how big the truck is .


regards pete

Its on the shelf now waiting till I finish present job and gather stuff for DUKW .

[wibblywobbly]

Your wish is my command, lol. Yes, they are a bit on the large size. Got 6 upgraded shocks on their way as the weight of the new bodyshell is too much for the standard ones.

[971wright]

Hi That's it Rob shows just how big these trucks are. Seeing a photos of one dosnt give you an idea of the size. The Dukw will be 950mm long 260 mm wide , it will also need suspension beefing up ,which shocks did you use for yours .


regards pete

[wibblywobbly]

These are the shocks, they have adjustable preload, so can adapt to any bodyshell weight.

http://www.ebay.co.uk/itm/262216515506? ... EBIDX%3AIT

My front ones are so weak that the chassis is resting on the transmission before it even starts moving...