Activity Feed › Discussion Forums › Software, CAD & Mapping › Got my printed battery case
There are times you start something and you should just stop, but, you are just too far into to just stop. I have had issues with the wrong part, parts that were described wrong and scope creep to make me add things that there just is not room for. For those that haven’t wired a LiPo battery the cells are cross connected and individually connected to a Protection Circuit Board (PCB). The idea being that charging current to individual cells never gets above a safe level.
Wiring this is fun enough, especially for a very small battery. This is the three cells wired to the PCB and all of the other components sitting there. That very small circuit board in front is a step up / step down regulator that delivers a true 12.2 v by my tests on three of them. When you add all of the parts it feels like a mile of wire.
This picture is all wired up for large hands wiring, I just can’t deal with tiny little wires in tiny little spaces like I used too.
This is cramming all of the wires into every open space. Just need to attach the wire gland and the disc golf marking disc top
Finished battery. Runs the 360° for 4 hours and weighs nothing. What a bitch to wire and put together
The regulator did in fact keep a steady 12.18 to 12.22 v during the entire down cycle of the battery from 12.60 to 9.0 v. I have printed a larger day and half model that surprisingly has more room in it, but, it is still a week away. I just wanted to get these done first. 3 done parts for one more, but, I am waiting for the same print order to finish that one. These are 700mA and the day and a half will use 2000mA batteries
You do nice work! I enjoy reading about all your projects, but am partial to the ones that involve batteries and electronics.
That is pretty interesting. What will you use this battery for? The connector looks like the connector for my Topcon data collector cable.
Thanks Jim. I feel like I am a hack now that I can’t see, LOL
It is for Geodimeter / Trimble Hirosi ports. Really any cable can come out of it, but, these are Geodimeter/Trimble
For anyone else trying LiPo to 12v
To close this line of thinking the little, and I do mean Little, regulator works perfectly. It bench tested a solid 12.18 to 12.22 volts as the batteries went from 12.60 to 9.0 volts. It does run the 360° prism in the field perfectly. They list it as 80% efficient, but, it took the battery from a 4 hr and 15 minute battery to a 4 hr battery, so, it is more efficient than 80%
I have had the larger sized pole battery for a while now and placed one in service. It was with a full sized driver for disc golf on the top. The full sized disc was just too big and I was getting “kind” whining back from the field, so, I scrapped it and injineered my own top. It is not the most manly design now that I see it in person, but, it is strong enough. It is only about a half inch to an inch of free board, so, it was never designed to take the full brunt of a drop. I wanted it to significantly reduce the impact to the body, is the closest description I can’t get to what I was hoping for.
It is a lot bigger than the small 4 hour battery, but, it is just not that significant of a weight penalty. I was expecting it to feel much heavier swinging on the pole. It is noticeable on the pole the 4 hours are not.
The flexibility of the sintered plastic is giving right about the push back I was looking for. I didn’t give it a huge amount of up and down strength as that would have become a printing cost issue. It is strong, but, it will not win a pushing battle with a strong branch
I have two of these large ones printed for the batteries laid sideways. The new design (not printed yet) places the same 2ah batteries vertical and fits in the same triangle, well almost, as the little batteries, just taller. These can use the same disc golf discs as the smaller ones as well, so, if I need more they will look like this instead.
Since they are made, … they are going in service. I do think the disc’s need to be dyed black though, not orange
Just to close this. That little 12.18 to 12.22 volt output from the Paolo regulators may have looked fine, but, in actuality limited distance with the 360°’s. Using a calculator I came up with placing an inline resistor to step the voltage down to a true 12 volts. Each regulator was ever so slightly different in their voltage output, so, I bought a bunch or resistors (they’re cheap) and placed them in line until I had a true 12 volt. The “good” range does appear to be 11.95 to 12.05 volts. The average was a 1.3 ohm resistor and if you do the watts calc you need a 2.4 watt resistor so I used 3 watt resistors.
Next little project with be cases and mountings for a Parani LR bluetooth set. We are having no radio issues and still have a few on the shelf, but, this is something I want to look at as an improvement. No I haven’t looked into it far enough to even know what is needed yet, but, I wish that I had known to integrate them with the base battery design at the time I did that I can make them work together regardless. My Geodimeter / Trimble 3D printed radio cases are being tested currently and I can’t wait for the feedback from the dealer. These Geodimeter / Trimble instruments are still very good guns and a little modernization does not hurt, that and I have more than a few and don’t want to upgrade them yet
After using these batteries for a while we were having issues with the regulators failing in the 360° prism batteries. Traced it back to the diodes in the prism causing surges in the regulators (yes, I should have thought about that.) The fix is to install a capacitor bridging the out side of the regulators. Have had no issues subsequent to their installation
Pretty cool. You obviously have a passion for this type of stuff.
I will be looking forward to the Parani project!
Radios
Instead of fussing with Bluetooth radios that were never designed for distance, how about checking out these 900 Mhz radios at
A Trimble tech keeps telling me that you have to use Trimble radios, at least if you want to use the Trimble ACU, but if you are using another DC then I expect the Digi radios will work better than the Bluetooth. The radios cost $170 or $205, with or without the accessory kit. Cheers.
I just love 3D printing. The crew knocked over a back sight the other day and broke some parts. I know these Geodimeter traverse sights are long in the tooth, but, they are so well designed I want them working. I called the dealer and the parts are obsolete, … no problem, I whipped them up and ordered them. If they look as good as the models and fit, I am going to be very happy.
All this, for cheaper than it would have cost from the dealer if he had the parts! My only concern is that the ring on the base was the shear point for the level puck. It is a much weaker plastic than I am printing in, so, I designed in a shear groove to the top of that part for it to shear in case of another fall. Getting shear and strength numbers is so difficult for the original and printed materials, I just guessed
In the future the dealer will have the 3d model and print up the parts you need on demand. Or, perhaps, he will print the parts on your 3d printer over the internet.
I think there are a couple of business models for printing, but, I can’t see manufacturers releasing their designs, so I think you have it correct. The model will be king as it took me a little while to be good enough to whip out a part like this in a short amount of time
Slight hijack.
I miss those old Geodimeter prisms that you could slide up and down at ANY height along the rod, especially for those shots through the bushes that you can only see at about knee height..
Carry on.
Worked great. I had to “clearance” one thing with an exacto and fix the digital model
I did get a kick out of that little level bubble that is stock on these brackets. Since they are all atrociously out of level, I didn’t print them back in.
If anyone else needs one, I have left the models here https://www.shapeways.com/product/PUPE2KXW3/geod-500-glass-body
I had some old Geodimeter 400 traverse glass and decided that since I had the targets modeled I would order some wings for a coaxial instrument and make the glass usable. I ordered the new wings, got them and found out the yellow inserts for the 400 system are different and won’t work. I ordered some yellow inserts and got them a few days ago. I am impressed, I have done a lot of printing and know how accurate it can be, but, this snap in fit is amazing. The wings were printed at Shapeways and the inserts were printed at Sculpteo. Two different machines in two different countries by two different companies. The printed plastic in the picture is grainy and dull looking the Geodimeter plastic is shiny and smooth by comparison.
I know that the yellow will sun fade, but, I have placed them in service to see how quickly. Once I know, I will pull them out and paint themI need to update the instrument battery portion of this thread. I am using 3 LiPo batteries that have a current limit of 12.6 volts and low of 10 volts as it falls off so quick as to just consider that the low limit. The low limit is actually 2.4 v per cell or 7.2v, but, once the cells get to anywhere near 10v they drop so quick. I had two instruments that would not boot with these batteries, but, would boot with a plugged source. Checking the Ohm’s Law against what I was doing revealed the issue.
A Geodimeter takes 1.3 amps at 14.0 volts to boot, so, working that backwards 14.0v * 1.3amp = 18.2 watts. So looking at the efficiency of the regulator I was using yields 80% efficiency or 18.2 watts / 0.80 = 22.75 watts on the in side. With that info I can see the current needed to boot on the in side is 22.75/12 = 1.9 amps at 12 volts and 22.75/11 = 2.06 amps at 11 volts in. Basically I was right at the regulator limit on boot.
Placed a 5 amp regulator in this morning and every instrument boots and works fine. http://www.amazon.com/gp/product/B00MHTV8Z8?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00 I had set this regulator to 14.0 volts, but, I am going to turn it down so input and output differences are minimized. Heat wasn’t an issue with the 2 amp regulators, so, I am not expecting an issue with the 5’s as they will not be close to their limit. It is all about real world efficiency though. This is only a step up regulator, so, I need to keep the output greater than 13 volts, me thinks
The lesson learned in both the 360å¡ batteries and the instrument ones is that I sized the regulators too small to begin with. The instrument regulators are in the 360å¡ batteries now and the instrument batteries are now 5 amps.
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