Tolerances? The GR01's were + 1mm if I remember right
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Tolerances? The GR01's were + 1mm if I remember right
At very worst these are +/-0.1mm on part dimensions or +/-0.2mm on overall dimensions such as the distance from front to rear section mounting holes. It's a big step-up in precision from the GR01's
So, enlarging the 2 front holes, redrilling the 2 aft holes, adding some washers and shorten the axle should make it a 1 on 1 replacement for the GR01.
Shame both Conker II and Binky were water jet cut to match the GR01's, we are going to have to re drill those beautifully cut bases now :cry:
Or try to find some second hand onesQuote:
Originally Posted by Eventorizon
or make some different gr-02 mounts
Progress is being made, the shafts should be finished by Tuesday then gearbox assembly will begin in earnest.
https://lh3.googleusercontent.com/-v...014_213848.jpg
Having costed up the options we will be offering an external bearing kit for the GR02 for those who want to place a load or wheel on the end of the shaft but don't have bulkheads in which to put a support bearing. The bearing block itself may of course be used separately from the GR02 as well.
Apologies for the appallingly coloured render(!):
https://lh3.googleusercontent.com/-A...-plate-kit.jpg
That I like. Really good idea. Makes the whole product more flexible (not like that!) and brings them back into line for replacing drills.
Aha while I was reading though this I was thinking of suggesting that, but I guess you already had thought of it! And they look great though, may have to finally invest in a bruiser 1 upgrade, considering we break at least 1 drill gearbox and motor every event it may just become cheaper in the long run to replace them with those, plus the different ratios looks interesting means I could get more speed using 4wd!
That's a good point... we're breaking drill gearboxes constantly at the moment, with the three pins loosening on the second stage, often rounding those three metal gears, damaging the other plate and burning the motor out as they go. 12v motors at 18v. Lots of people overvolt the GR01s, and I haven't heard any horror stories. Why is that? Are the innards of these the same as standard drills? We'd upgrade to Gimsons if we could guarantee we wouldn't just strip these gearboxes too.
Of course, I can completely understand that putting 18v through a motor setup designed for 12v is a risk the person buying is responsible for. I just like the power between breakages. :proud:
Why do we eat gears (we more or less completely stripped 4 metal gears in one go when Jarvis and I were playing in the street) so much when 18v has been put through 12v drills without problems for ages?
Sorry for going off topic.
It's quite possibly just the stress you're putting through the gearboxes, that depends on the design of the robot. We had that issue with Boom. A drill would last about two fights which wasn't good. Sometime the casing would rip itself apart, sometimes the gears would strip.Quote:
Originally Posted by Relentless
We reduced this by using o rings on the drills instead of grub screws but didn't cure it completely. Would tell you how the Gimsons perform if i hadn't blown the whole thing up at Barnsley this year by accidentally putting two wires together which should never have been put together.
They are a darn sight better built than drills though.
Think I'll need to start charging you consultancy fees in the future Ewan :lol:
No doubt the reason you're getting through so many drills Ellis is you're simply taking them to the limits of reasonable voltage and wheel size combination, there could however be the added element of flex in the gearbox adding to the problem. If a planetary gearbox is taken out of alignment (with the shaft twisting relative to the ring gear) then some of the planet gears will be periodically under greater stress than the others. In this regard it's good to have a rigid gearbox structure in order to maintain alignment and distribute the load more evenly, something which the GR01 seems to have been able to do (judging by the lack of reports of stripped gears). The same applies for the carrier plate pins, if alignment is maintained they should be less likely to loosen.
There's an additional component of quality of manufacture which is hard to put any figures to. As I've mentioned some time before the components for the GR01/2 come from a factory manufacturing drills for the American market which retail for $30-40 a piece. It's possible that they have better quality control at such prices over £10 European retailed drills, I haven't come across any badly formed or loose-pin parts so far at least.
It will be interesting to see whether there's any problems at all with gears stripping on the 24:1 versions which feature the same size of gear on the output stage which will of course be under a smaller torque load.
All this said though combat robots are such a volatile environment that you can never be sure of any completely foolproof combinations, hence why a full range of spare gears and carrier plates will be available for the GR02!
Most accessories for the GR02 are now online, including gear carriers, planet gears and pinions. The motor itself will be going online later this coming week.
Too keep you all updated: The one thing holding back the GR02 launch at the moment is (oddly) the weather. I'm having to wait for some decent sunlight for picture-taking, although I have just started to repair an old lighting rig as well so it'll be whichever comes good first!
Pictures have now been taken and a release date has been set:
http://www.gimsonrobotics.co.uk/prod...unch-image.jpg
As promised: (click through for the product page)
http://www.gimsonrobotics.co.uk/prod...ions_large.jpg
Although not detailed on the product page, if you purchase a GR02 any time in the next couple of weeks then you will qualify for a discount on the external support bearing kit when it is released. You will be able to purchase them for £2.80 rather than the usual £5.20 each, and with free postage.
If you've any questions about the product or ordering please use the contact form here.
Looking good and the price seems reasonable, I shall be buying
I was looking at the high torque motors as well - just wondered if anyone had used those as a weapon motor?
I would stick with the new 36:1 18V motor GR2 as it has a torque of 18.1Nm, the high torque motor has a torque of 11.9Nm. Also the shaft diameter is 2mm bigger so less lightly to break, also better mounting options.
So in summery
They are more powerful. (over 3 times)
They have more torque.
They are stronger.
They should be easier to fit.
Oh and they are cheaper :mrgreen:
Which one will I be using in my next Featherweight :uhoh: robot
The High torque motor would come into it's own if you wanted a slow speed 45-50rpm so it will have it's uses for particular situations, I don't want to slam it completely, it's a good motor but normally the GR1 and presumably the GR2 are better for most applications in the fighting robot environment. :D
Good points. Should of read the spec properly :oops:
Really looking to an alternative to a Dewalt powerdrive kit. These do 45 Nm at 450 RPM which geared down should be good for a lifter
This is higher than the GR02 (my latest feather has 4 GR01 so all for using them :) ) but apart from building a custom gearbox there don't appear to be too many alternatives. Most Dewalt's on ebay look on their last legs
Ours (14.4v AEG) looked on its last legs. It was battered and filthy, long-dead battery, sitting in the sun for ages, and we only opened it up out of interest. Biggest cordless drill I have seen to date, all others that we have found have smaller motors. Don't know how it compares to the powerdrives in torque terms, but it has buckets of it anyway!Quote:
Originally Posted by shakesc
/on topic
The GR02s are looking really good. We may well buy in the future. :)
Thank you to all those who have bought motors so far, there's another batch of the GR02's about be dispatched today. I've just finished doing some re-touching on the product images as some of them were a bit too bright/washed out before.
For those of you wondering the GR12 could well be used for some form of weapon drive, especially if you were to replace the relatively low power 555 size motor with an HRS550. You would probably want to put an additional reduction stage after it but the main advantage of the gearbox is large carrier pins some 4mm in diameter and planet gears >8mm wide, able to handle much greater torques than most similarly sized gearboxes. These were originally sourced for a customer requiring winch-motors for cameras on a fish farm but seemed useful enough to put on general sale as well.
I've had a few questions by email about availability of wheels for the GR02's, it is likely that a new source for these in various sizes will be added in the next two weeks, I will keep you all updated.
What's your biggest planned size?
Unknown, to be determined soon.
The external bearing mounts have now been completed:
https://lh6.googleusercontent.com/-5...102_163201.jpg
Proper pictures will be taken and the item put online by Monday/Tuesday. As previously mentioned all past GR02 customers will be sent discount links in due course!
Deans connectors are back in stock, also 550 sized 9.6V motors are now only £4.50 each, only 11 left to clear.
The external bearing kits are now up:
http://www.gimsonrobotics.co.uk/prod...earing-kit.jpg
I will be sending discount links to previous GR02 customers later today
The block has overall dimensions of 40mm by 32mm and is 8mm thick. Each is included with two mounting screws,
either two M3 x 8mm screws
(perfect for use with the GR02)
or two M5 x 20mm screws
(option selectable below). The screw socket size is 4mm. The centre-to-centre distance between the two mounting holes is 32mm.
shouldnt that read either two M5X8mm screws
look good Ewan, though id make those shafts shorter with the thread closer to the bearing....
received my bearing block today
Looks good and fits well
Ah yes, thank you for alerting me to the typo, has now been amended!Quote:
shouldn't that read either two M5X8mm screws
The output shaft is based on a one-size-fits all basis, to have a variety of sizes would be considerably more expensive. When the wheels designed for these motors are released they ought to do away with the 'overhanging' wheel arrangement many people presently use as the nut insert will be designed to be used on the far side of the wheel with a 12mm inside bore surrounding most of the remaining shaft length. In this way the wheels will be significantly closer to the support bearing(s) than if their bodies hung off the far end of the threaded section as is typical with today's Blue wheels.Quote:
look good Ewan, though id make those shafts shorter with the thread closer to the bearing....
Good to hear Chris!Quote:
received my bearing block today
Looks good and fits well
Details on a range of wheels are still being worked on, I will update when more becomes clear. There should be 75mm, 100mm, and 125mm diameter versions available.
turning the wheels around (so to speak) is something I did with GR01 and some robochallenge wheels. Just drilled them out a bit more and ran a tap through the thread. Benefit is that it makes a more compact unit as well
Absolutely, the whole package of wheel and motor ought to fit comfortably within 145mm if arranged this way.
I have reversed the Robochallenge wheels on both of our new machines. It makes it 25mm shorter; 40 if you go by the wheel position.
But caution! I found that when driving the wheels would tighten onto the front face of the motor. This happened to one and it burnt out the motor in a massive cloud of smoke! The way to stop this is to add a M8 washer onto the shaft and remove all the plastic up to the bolt on the inside of the wheel. The means as the wheel tightens if comes to rest on the washer, not the motor.
If these new wheels do the same thing but are designed for it, I will probably swap to make the set up more reliable!
We have recently changed motor supplier for 550 sized motors and as a result we have been able to reduce the price of the GR02's, now only £29.50 for the 12V version and £30.50 for the 18V version.
The motor prices have also fallen, now £5.90 for the 12V and £6.90 for the 18V.
There is the possibility of 24V nominal motors being added in future, I am currently in discussion with the manufacturer.
Finally, there's only a handful of 9.6V motors left, priced at a paltry £3.90 each, catch them while you can.
Ewan
you pulled the notification of wheels coming soon off the website
Have you shelved the plans for a while?
Hi Chris,
Yes unfortunately - I'd been discussing with the Robochallenge guys since early November about Gimson Robotics becoming the exclusive outlet for a new model of wheel they've been developing, but they've kept putting the date back due to various projects. I still hope we can put something together but for now I haven't any idea when anything will be ready. As soon as things progress I'll be sure to post here again.
We've now taken delivery of a custom batch of 24V 550 type motors for products including the GR02. There's still testing, photo taking and website updating to do however, so expect these to be online later next week.
Just as I was thinking about overvolting my 18V ones to a 6S LiPo. ha, should have waited. :?