Register To Comment
Page 1 of 3 123 LastLast
Results 1 to 10 of 26

Thread: Build Diary - Plastic Fantastic - FW

  1. #1
    Al_'s Avatar
    Member

    Hi everyone, after finishing the upgrades to Pressure Point and with plenty of time remaining until the events start up again, I have decided it’s time to build another featherweight. I have been working on it sporadically over the winter has time as allowed and decided I better get a build diary up before I forget what I did.

    The aim for this one is to be fairly simple, I want something that I can throw into the arena, hopefully come out still working, charge the batteries and then throw it back in for the next fight without too much other work. I also have not fought any spinners yet and this will allow me to see what works and what doesn't before committing too much. Therefore I’m going with a 4wd ram bot, this should keep the design and internals fairly straightforward. It’s going to be constructed out of 1 type of material, HDPE which should keep costs down as I can make all the parts myself. The fixings will be kept all identical where possible to further aid with this. Motive power will come from 4 of the mighty Argos value drill motors, each one directly driving a wheel and each side pair of motors driven off 1 TZ85A flashed to brushed motor operation. Voltage will be as 5s as it gives a good speed/power boost to the motors and they seem to handle it without too many complaints.

    With the above in mind, I set about coming up with a design on Fusion 360, its a fairly standard invertible 4wd ram bot type design. The chassis bulkheads are all 20mm HDPE witht the mounts for the motors milled directly into them. Side and rear armour is also 20mm HDPE, while the top and bottom are 15mm. The front wedge is 30mm thick but I think I might end up needing a small steel running strip along the sharp end of the wedge as the HDPE won’t hold the edge, but that should be the only non HDPE part. Fusion puts the weight in at around 11.7kg, so hopefully a bit of scope for it inevitably weighing more than you expect. The name of the machine shall be Plastic Fantastic since it is built out of the stuff.

    The HDPE came from Direct Plastics, all natural white as I’ll come up with some sort of decoration scheme when it’s done. Fusion 360 spits out g-code from its CAM module that I can send straight to my CNC router so it wasn’t too long before the first part was made. It’s one of the main bulkheads that surrounds the battery compartment, and here it is before it was cleaned up.

    IMG_20171102_132728577.jpg

    A couple more parts later and there is the other battery compartment bulkhead along with one internal side. You can see the mounts for the front of the motors in it. Apologies for the poor picture but its the only one I have of it at this stage.

    IMG_20171104_173347323.jpg

    More to come soon.

  2. #2
    Fancy giving us a image of the CAD ?

    Also what CNC router do you have? personal or work?

  3. #3
    Ocracoke's Avatar
    Team Kaizen

    Looks good so far - reminds me of the FW version of Limpet from the description.
    Team Kaizen - Build Diary for all the robots

    AW: Amai, Ikari, Lafiel, Osu, Ramu
    BW: Shu!, The Honey Badger
    FW: Azriel
    MW: Jibril, Kaizen

  4. #4
    Al_'s Avatar
    Member

    Quote Originally Posted by Maxamuslead View Post
    Fancy giving us a image of the CAD ?

    Also what CNC router do you have? personal or work?
    Here is a quick look at the cad, sans nuts and bolts which I never seem to put in. The side tippers which stop it balancing on its side are still up in the air. I’ll see what dimensions they need to be once it is built and I can test it. The battery lives in the centre compartment, ESCs are in the front and the link is in the back. My router is a personal one, a Chinese 6040 off eBay. The consensus seems to be that the machines are ok for the money but the electronics and wiring are junk. As it happens I’ve already replaced a faulty connector on it and the PSU died over Christmas, so I’ve replaced that too. I’m going to replace the stepper drivers and all the wiring/connectors as things allow but otherwise I’ve not had any problems with the machine itself.

    Cad.PNG

  5. #5
    cool which ebay listing did you get as I am looking at 4030 version and from what i have read the older one had better quality control boxes.

  6. #6
    Al_'s Avatar
    Member

    I cant find the exact listing right now, but mine is over a year old and if it has a 'better quality' control box then I'd hate to see one of the newer ones! Mine has the generic blue control box, here's a picture of it.

    IMG_20171012_133022724.jpg

    As I said earlier the boards inside are not great designs are built down to eliminate every bit of cost they can. This control box also has the PC interface and stepper drivers as an all in one board (I know some others have them separate) so when a part on that board inevitably fails too it will mean replacing the whole board.

    Another point to note about the older control boxes is that they are nearly all parallel port connectors and require a PC (not laptop) with a native parallel port, not one on an add in card. There are lots of old PCs going cheap on eBay with parallel ports but its another expense and hassle to bear in mind. Some of the newer control boxes reckon to be USB connections which would be much easier but I don't know how that would work with whatever software you plan on using to control it with.

    Having said all that, don't let it put you off. I got mine to play around with and try and learn something along they way. I had no knowledge of any of this when I started and I'm starting to make some passable parts for my robots for now. For woods, plastics and soft metals (within reason) these machines seem good for getting started on, just keep their limitations in mind.

  7. #7
    that stuff with the parallel board is a load of bull, but it is good to here that the blue control boxes better then some people are making out.

    This is the one I am planning to buy but if the blue control boxes are fine i could get a "cheaper" one.

    sorry for the thread hijack but what spindle are you using and did you cut Presser Point's crusher assembly (arm and frame) with it ?

  8. #8
    Al_'s Avatar
    Member

    I didn't cut Pressure Point's arm and frame on it as they were made before I had the machine and so were water-jetted instead. Any new bits I attempt for it I'll do on the machine though, but from the aluminium I have tried on it, don't expect quick cuts.

    Looking at the one you have linked, the machine itself looks virtually identical. The steppers are smaller and the spindle on it is 230w, I have the 600W air cooled spindle on mine. I don't know if that would hinder your ability to cut soft metals on it or how fast you could cut them but someone with more knowledge may be able to comment. The ER11 collect limits you to around a 6mm bit, but I don't think you'd want to be pushing a much bigger tool around with it anyway.

  9. #9
    Al_'s Avatar
    Member

    Continuing with the build diary, the next parts made were the left side, its spacer and the left hand rear motor mounts, plus all their respective mirrored parts for the right hand side. I fitted a couple of motors with their wheels and assembled what I had of the bot so far:

    IMG_20171112_154608600.jpg

    Only 2 motors are shown in the picture as back when that was taken there seemed to be a national shortage of the 12V Argos Value drills, and I couldn’t get hold of any more. Thankfully this situation seems to have sorted itself out and I have some more and the drills are back in stock. At this stage the chassis was starting to get some rigidity to it which was encouraging. There is a fairly large gap between the wheels and the chassis to allow for a bit of chassis deflection but also for wider tires should I need in future.

    Next piece to be made was the back, in the same style as the rest and here it is fitted, along with the other 2 motors and wheels. At this stage I now had something I could roll around the workbench.

    IMG_20171208_134353162.jpg

    The final part to complete the chassis was the front wedge and it was also the longest part to make, a combination of being the thickest piece and having an angle to cut on it (unlike all the previous parts which where all straight sided cuts). Here it is at the start of the cut, at the end and the finished piece.


    IMG_20171208_130826110.jpgIMG_20171208_142940336.jpgIMG_20171208_144700729.jpg

  10. #10
    Looking great - super chunky and sturdy! Should be very difficult to KO.

Register To Comment

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •