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I have just found and ordered a £10 cordless drill from Argos. I figured building on a budget this was great! Charger, battery, motor and gearbox for a tenner!
I have ordered 2 and waiting for them to come, I'll let anyone else building on a budget whether they were worth it. In mean time has anyone else had experience of this particular drill in a robot?
http://www.argos.co.uk/static/Product/p ... +DRILL.htm
Anyone else got any building on a budget tips?
PJ
ask in the wanted section for section hand parts. You will find most people have old electronize speedos, old radio gear or old chassis kicking around that are no longer being used which are still just as good if not a little battle worn as new. Usually you will find they cost around 40 to 50 % of the price brand new so its well worth it when starting out.
They should be worth it, as the motor/gearbox inside it is likely to be very similar to the motor/gearboxes in a lot of other low-priced cordless drills which have been used several times in many robots with high levels of success.Quote:
Originally Posted by PJ-27
Some people seem to be unfortunate in the sense that drill motors don't tend to be reliable for them and they go through several replacements. It could be the way they are mounting them etc or it could just be that for whatever reason, their robot doesn't like drill motors. But cases like these are significantly less than cases where people have had success with drill motors.
I tend to use drill motors because they are light, cheap, moderately fast and come pretty much ready-made. I also have my own preferred way of mounting them (that is low-cost for working on a budget) that seems to work well. Thanks to Robo Challenge, attaching wheels to them is a doddle too.
Basically they are a good all-in-one option for drive motors. You could go for more powerful motors, make your own transmission system and have an extremely powerful and (probably) fast drive system, but for anyone who doesn't have the budget or facilities to make something like that, these are ideal.
What is your preferred way of mounting them? If you don't mind my asking...
I will check out the for sale section, as I need 2 speed controllers and I'm working on a very tight budget. Our team motto is to salvage as much as we can to make our robot and spend as little as possible, obviously in some cases we will have to spend (ie, getting 2 identical motors, gear boxes, chargers and batteries).
Thanks,
ps. I'll put a request in the sale section to see who is selling what.
I'm using the Argos drills as well. It's Same method as any other drill with regards to disassembly isn't it?
I'm using this guide;
http://www.robowars.org/guides/guides-d ... cking.html
Found it somewhere on the forum......
Never used a drill for something other than drilling before!
It is similar to the Robo Challenge mounts in the sense that I support the motor at the gearbox end. Basically, I tend to use a bulkhead design in my robots so I cut the back-to-back-D shape of the front of the gearbox out of whatever material I'm using for my bulkheads (usually some form of plastic). Usually the depth of the gearbox at that part is 20mm so my bulkhead material either has to be 20mm thick, or if it is thinner, I have to cut the same shape out of a thinner piece of material and use it as a spacer. I then bolt the whole motor in place using the mounting plate supplied with the drill (this is a round black plate, maybe around the 50mm diameter mark with two holes in it that you will see when you remove the chuck from the drill. It holds on the torque ring and you need to unscrew it in order to remove the torque assembly)Quote:
What is your preferred way of mounting them? If you don't mind my asking...
I should probably get some decent pictures up of what I mean because I feel I don't quite explain it as clearly as it could be. Essentially though, it is a pretty quick process and I've never had a problem with drill motors mounted in this fashion.
Thanks for the detailed explanation! Some photos would be great.
there is a picture already up Jamie shows some detail
http://i31.photobucket.com/albums/c367/ ... uild22.jpg
alex
Well if that picture helps then good :)
I'll probably have to disassemble the robot at some point before the upcoming champs just to go over everything so I'll try to take some step-by-step photos then. What I should add actually is that, in the Drumroll 2 build - so the picture above, I didn't bother cutting the back-to-back D shape to match the gearbox. Instead I just cut a 30mm x 25mm rectangle in the material as this is overall width and height of the gearbox and once the round plate is screwed on it still provides a sturdy enough mount. Once you get your hands on your drills and take them apart, you'll probably understand these ramblings more easily :crazy:
Yeh I plan on taking them apart and then re-reading everything you said!
Cheers,
Have you taken them apart/ruined them yet? Are they any good? I'm thinking of buying a couple for a featherweight I want to make.
From what I can tell the insides are just like any other drill, although at 12v they are at the lower end of most drill ratings. We plan on over volting them to 24v though. I'll post again when they are in the bot and running.
i personaly would only go max of 14.7v they might burn out ar 24vQuote:
We plan on over volting them to 24v
I have read both ways, overvolt to twice as much and 1.5, think ill start it at 18 and see how that goes. I figured it'll just be a lot of start stop for 3mins, so the motors will infact have very little travel. Although I could be wrong in my thesis....
In terms of charging, I currently have two 12v chargers, for each 12v battery, will using the same charger for my made up 18v (same cells) be alright?
Rule of thumb for overvolting a fairly hot wound dc motor like a drill is 1.5x rated voltage so you'd be looking at 18v.
the travel won't be much however that's irrelevant. It's all down to the current that the motor will draw. As you will have a lot of start and stops, the motors are in essence stalled for a fair bit of time, hence drawing large currents. 1.5 times the voltage will leave your drill motors too warm to touch after a battle. Believe me, I've touched them :)
No it's not ok to use a 12v drill battery charger to charge an 18v pack. Buy a decent and scrap the drill one. It's junk
ok, we plan on getting some decent cells at some point, 2-3 charge isn't going to be manageable! Are chargers voltage dependent? Would I need an 18v charger specifically? Just thinking the voltage of the packs may get modified at some point until we find whats best.
As you will see with the example here
http://www.technobotsonline.com/pro-pea ... arger.html
All decent chargers will tell you that they can charge up to a certain number of cells. Basically they are intelligent chargers, able to tell the number of cells being charged and hence they are able to charge and then automatically stop. You will find a lot of intelligent chargers require the use of a 12v power supply input. You will therefore require an external power supply to plug the charger into. There are some that plug straight into the wall but I'm not familiar with those specifically (been a while since i've had to buy a new charger!).
There a little pricey, what about just for testing? And then in the future we will look to buy new cells and chargers. The chargers for the drills would effectively being charging 7-8 cells instead of the 10 they were before. Just want to get some juice in them.
why bother shelling out twice then? Buy a decent charger now and you save yourself the hastle of spending more cash in the long run. Don't get me wrong, I realise you are trying to build on a budget, but if you are planning to be building bots for the long run then I'd highly recommend buying a decent charger and power supply.
A quick search on ebay threw up this
http://cgi.ebay.co.uk/iMAX-B6-Lipo-NiMH ... 27acfe62c0
Should be able to do the job you're after. When building bots, ebay is your friend!
Thanks for having a search!
Yeh eBay is a great place to fin what you need! May just get that very charger.
Cheers,
Turns out we each have an old Ni-Cad charger each that will charge up to 8.4v, so I'm going to just make up 2 packs and charge them individually.
Hi
i've got an old charger i no longer need its an intelligent charger with built in wall plug much easier than a power supply
interested >??
PM'ed
I think we are going to muddle on with what we have.
Anyone know what sort of gauge wire I should be using? Should I account for peaks in current?
I don't actually know what sort of wattage I'm looking at for the drill motors.
Overkill can't hurt, 10 or 12 gauge will be fine.
Is that AWG?
Cheers,
yes awg
Halfords subwoofer power cable would be sufficient and its very well insulated
[quote=k_c_r]It is similar to the Robo Challenge mounts in the sense that I support the motor at the gearbox end. Basically, I tend to use a bulkhead design in my robots so I cut the back-to-back-D shape of the front of the gearbox out of whatever material I'm using for my bulkheads (usually some form of plastic). Usually the depth of the gearbox at that part is 20mm so my bulkhead material either has to be 20mm thick, or if it is thinner, I have to cut the same shape out of a thinner piece of material and use it as a spacer. I then bolt the whole motor in place using the mounting plate supplied with the drill (this is a round black plate, maybe around the 50mm diameter mark with two holes in it that you will see when you remove the chuck from the drill. It holds on the torque ring and you need to unscrew it in order to remove the torque assembly)Quote:
Originally Posted by PJ-27:1ldlr8r3
I should probably get some decent pictures up of what I mean because I feel I don't quite explain it as clearly as it could be. Essentially though, it is a pretty quick process and I've never had a problem with drill motors mounted in this fashion.[/quote:1ldlr8r3]
Photo time :)
This is the cutout I make in my chassis bulkhead to accommodate the front end of the drill gearbox. I used to make the back-to-back D shape as mentioned, but now I don't bother. Instead I just cut a rectangle, usually around 30mm x 25mm in size:
http://i31.photobucket.com/albums/c3...r2_build35.jpg
This allows the drill motor to slide through the hole and have the shaft protruding on the other side. You can either have it as a tight fit or it can sit loose in it; I usually try to go for a bit of snugness (sorry for the blurry pic):
http://i31.photobucket.com/albums/c3...r2_build36.jpg
The depth of the gearbox is roughly 20mm, so spacers may be necessary for thinner bulkheads. For example, here my bulkhead is 15mm thick so I've used a spacer made of 8mm HDPE to take the depth to 22mm. All I did was use a hole saw to cut the spacer out, and then cut the 30mm x 25mm rectangle in that too:
http://i31.photobucket.com/albums/c3...r2_build37.jpg
I then put the black metal plate from the drill torque assembly over the spacer and screw it into the holes in the front of the gearbox using the same screws used in the torque assembly. Job done!
This is brilliant, thanks for the thorough guide!