W.I.P Portal sentry turret - fully working replica


Well-Known Member
Yes it was my lock down project and what I was supposed to be doing after my initial ZF1. I decided instead to see how far I could go with the ZF1 kits, and I will return to this project as soon as the first and second batch of ZF1's are out in the wild.

I will wire it up and get it shooting some BB's in my new workshop at some point soon!


Well-Known Member
Just a couple of images of where the model is right now. Obviously it’s really easy to create things on the screen, but if you know at some point you’re going to have to fabricate that part, you generally take a bit more time working out what goes where, why and will it get in the way later?



The lower image shows the design so far off the main carcass and legs. The real concern is how the body will hold up on those spindly legs and how much twisting movement there will be when the guns pan and tilt.

The thin leg spindles will be fabricated from bent steel rod, with the pointy leg bits probably moulded and cast out in resin. The upper legs will also be fabricated steel sheet I think, to add a bit of weight to the construction.

The main body will be made from different hollow ‘boxes’ of folded sheet aluminium, as these will need to hold electronics, batteries and remain as light as possible, with most weight being situated in the arms and gunpods, and the large hopper of BBs in the ‘head’ of the turret.

Thanks for looking!


Active Member
This is an excellent project, can't wait to see it finished. Those legs present an interesting engineering problem.
Last edited:


Well-Known Member
Yes I was thinking I could do something with counter rotating weights to try to offset the torque from the rotating tilt/pan mechanisms, but this only increases the overall weight of the main body.

I think I will have to compromise on the original design of the turret, and increase the diameter of the leg rods significantly, to mitigate any wobble when the whole thing is moving about. I think bending pipe instead of rod might increase the rigidity too.


New Member
This is fantastic!

I bring a Weighted Companion Cube to Burning Man, and of course have thought about a few sentry turrets too. However, in my case, the most they would do is shoot water, or blow bubbles, which would make the overall mechanism a lot lighter.

Oh - also, my cube is a steampunkified, so I could probably make my legs out of regular table legs in my version of this, but given how much machining you're doing, it's making me think there's no way; I don't have access full time to that kind of equipment.

What size of mill / lathe would be required? I'm really tempted to get a Harbor Freight mini mill.


Well-Known Member
It all depends on what you want to make I guess. You don't need a large pillar mill, a standard desktop one would be fine. Lathes are a bit different as the pipe I am turning in this project needs a slightly larger chuck then most of your standard 'hobby' lathes have.

The Harbor Freight mill you specified would be a good start. The big cost is always the tooling, as you'll always need the one tool that you do not already own!

If you're going to be shooting bubbles or water, the main weight will be in carrying the water, and not the mechanism. If you're planning on storing it somewhere else, and pumping it to the mechanism, then it's not a problem.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.