andy watson Posted March 7, 2009 Share Posted March 7, 2009 My 80" stuka will be needing servos soon- 12 of the little blighters. 2 ailerons in the wings need to be micro I think, the rest can be standard. I don't want to bankrupt myself, so would like to keep it in the region of £100 for the lot. Can you recommend any? ps set up is like this, and it's a Futaba receiver. 1*Throttle 1*Rudder + Tail 1*Elevator 2*ailerons (limited room) 2*dive brakes (ineffective- more for show) 4*Flaps 1*bomb drop. Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted March 8, 2009 Share Posted March 8, 2009 Personally I think budget allocation is wrong here - an 80" scale model deserves more money on the critical components than that. Figure the total cost of the whole model, and then see if £8 a pop for servos is a fair percentage. Quote Link to comment Share on other sites More sharing options...
andy watson Posted March 8, 2009 Author Share Posted March 8, 2009 Well I thought it was a reasonable figure- the overall budget will be.......well that depends really- I think the siren is going to be expensive. The thing is that servos seem to be a minefield of price and performance. It appears you have a multitude of brands, and that cost and speed and torque are not always related. I don't really have any idea of what my "base" limits are. Obviously more speed and torque is better than less- but what are the minimums I should be aiming at? Looking at hobbycity last night I came up with the following that all seemed promising: http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=7026 http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=4370 http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=662 http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=5426 http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=3743 http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=6337 All these were rated 5/5 by customers. Sorry for the underline- it won't let me take it off! They range from a digital high torque (5.8kg) servo for $22.75 to a micro servo with 1.6kg of torque for $3.65. The problem I have is there is another standard servo in the list with 9.7kg of torque, same 0.12 speed as the digital but it only costs $12.95. What do I get for my $10 (and it's not just they are digital- this kind of price variation is common)? And what kind of torque do I need? Quote Link to comment Share on other sites More sharing options...
Dave S. Posted March 8, 2009 Share Posted March 8, 2009 The main thing you need in a model like this one, Andy, is reliability, so personally I would go with a recognized brand, not some far-eastern cheapies. If you are using Futaba radio, then you can't go far wrong with Futaba servos. Standard 3001 on most surfaces, maybe splash out on the the cheaper digitals (3152) for rudder & elevator. Cheap servos could prove to be very expensive when they cause the premature demise of a model that has taken much time and effort to build. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 8, 2009 Share Posted March 8, 2009 I'll echo Dave here, I've just replaced the cheap chinese made flap servos in my Cessna 182 because they caused intermittent glitches - a Cessna doing random flick rolls doesn't look good! Stick to Futaba or JR and you can't go far wrong. Quote Link to comment Share on other sites More sharing options...
andy watson Posted March 8, 2009 Author Share Posted March 8, 2009 ok, but what kind of torque do I need? Working on the basis more torque=more cost then I don't want to buy servos that are too weak (obviously), but I also don't want to waste money on excessive torque I don't need. The 3001's look fine to me- about the right price too- is 3kg enough? The 3001s really are good to illustrate the point here though. What about the 3003? Both the 3001 and 3003 have the same speed; but the 3003 has 3.2kg of torque compared to the 3kg of the 3001, so is slightly stronger. The 3001 is ballraced, the 3003 isn't- does that matter? The 3003 is half the price. I am more than happy with standard futaba servos, as long as I know they will be up to the job, and not massively over budget! Quote Link to comment Share on other sites More sharing options...
Dave S. Posted March 8, 2009 Share Posted March 8, 2009 The ballraces help to make the 3001 more reliable, I have had plenty of them in use for years, never a problem. I am sure the torque will be enough for a scale model, as you won't be using large surface deflections. If you really need more torque, then consider a 6v rx battery, or even separate supplies for rx and servos (I have a gadget upstairs for that, optical isolator that also allows different batteries for rx and servos, you can have it for £20 if it's any use to you). Quote Link to comment Share on other sites More sharing options...
namustang1a Posted March 8, 2009 Share Posted March 8, 2009 Hi have a look at giant cod,,i got some mini metal geared servos from there and thay are fine thay also do standerd size metal all have good tork .im very happy with mine Ian (also on a budget) here and here Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted March 8, 2009 Share Posted March 8, 2009 I reckon the S3001 are good value too - you can get deals on them which would work out at around £120 for the dozen you require - a bit over your budget, but not much. Also remember that digitals, although perhaps more prcise, are un-necessary for certain functions like flaps for instance. I prefer ball bearing output shafts over digital electronics ona £ for £ basis. Digitals also use more juice from you power supply system which I hope you have given due consideration to. Again, on a nice scale model like this, I recommend you do not skimp here.... these type of units are great for instance and well worth considering. Quote Link to comment Share on other sites More sharing options...
Bruce Richards Posted March 8, 2009 Share Posted March 8, 2009 I have used lots (40-50 including selling to club members) of TowerPro SG5010 and never seen or had a problem. I was buying them for under £5 last year but they are more expensive noe. Take a look on Ebay. They have good torque and BBs. Just my experience. Quote Link to comment Share on other sites More sharing options...
Dave S. Posted March 8, 2009 Share Posted March 8, 2009 BTW, you mention using micro servos in the wing - personally, I would never use them in anything IC powered as the feedback pots are very fragile. Fine in low vibration environments, like electric models or gliders, but never in an ic model Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted March 8, 2009 Share Posted March 8, 2009 Dave is right - not suited to IC powered ....large models especially Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted March 8, 2009 Share Posted March 8, 2009 hello andy-i would also go with the flow-get the best you can afford-showtime will be with us shortly am sure you'll get what you need for a decent price--stay in for a couple of night's be a good lad--keep you on the team with her indoor's and bingo a box of futaba 3001's.........happy stuka..... ken anderson.............................. Quote Link to comment Share on other sites More sharing options...
andy watson Posted March 8, 2009 Author Share Posted March 8, 2009 Hmmm 3001s or those Towerpro ones look like a really good servo......... We need this forum to have a poll option! Quote Link to comment Share on other sites More sharing options...
Chris Channon Posted March 9, 2009 Share Posted March 9, 2009 Hi, i have a Great Planes Super Stearman, 1.20 size, and great planes reccommend that futaba 3003 servo's are fitted. This aeroplane is about 14Lbs in weight, the only mod i carried out was to fit a servo again a Futaba 3003, to each elevator half, just to build in a bit of redundancy. A lot of hype is talked about regarding servo power, i have a Precedent Stampe 1/4 scale which was produced (kit) in the early 80's and all that was available then was a standard servo of a lot less power than is available now, and it does fly well on standard Sanwa servo's. So even though the new digital servo's do add a lot of holding power, a lot of aeroplanes do not need the the extra holding power, perhaps it is a " Bling" thing? ON a different note, taking new technology in to account, is using the new Futaba 2.4 gig radio, the response time is is greatly improved, ie you move the stick and the control surface moves but with a much better authority than with 35 mgz. So perhaps the ideal would be Futaba 3003 servo's with the new 2.4 gig technology? Regards Chris Quote Link to comment Share on other sites More sharing options...
Andy Harris Posted March 10, 2009 Share Posted March 10, 2009 I've had a 3001 fail on a Dualsky 260, probably a pot issue since the control surface jittered all over the place. I've got some TowerPro MGs that drove some cupboard doors for a couple of years. The cheaper servos I use for the indoor season. However it Hitec that I prefer for anything to fly a a club. The digital Hitecs feel more responsive and consistent with no trim drift. I believe you should reserve £20-25 for the alierons and elevator, then say £8-16 for rudder and throttle and the rest can be towards the budget end. Investing in the important control surfaces adds to peace of mind and piles on the flying pleasure. Andy Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.