View Full Version : See Saws
small.planes
06-26-2008, 08:24 AM
Ok, so Im going to make some new better see saws. :thumbup:
however I have not actually bust any yet, I guess my TH finger saves the day.
anyway, for those of you who have bust them how do they fail?
I suspect the thread on the balls pulls out / bends then pulls out?
Are replacements with new bolts, but not bearings etc ok? Ive got a box of longer m1.4 cap heads, but no spare bearings.
Dave
brandon_8
06-26-2008, 10:24 AM
I have had the balls rip straight out of the holes (strip out) and also have had the actual arm part snap clean off between the ball and the bearings. Usually, the bearings are still good, same with the ball if you can find it. But the screws that hold the balls and the see saw on are usually toast as well as the actual see saw arm.
I'm glad someones thinking about taking on this task. Its much needed.
Hi Dave, sorry for the delay sending the titanium. Its in the post so you should get it tomorrow or Saturday.
I'm not sure if you've seen this but Stoatnchips posted it a while back. If you can make the arms similar to this they should be far stronger than the originals. The ones I've trashed have all bent at the threads. Basicaly, theres not enough material around the screws. http://www.helifreak.com/attachment.php?attachmentid=47598&d=1210359804
small.planes
06-26-2008, 02:06 PM
yeap, Ive got a printout of that sitting by my mill :YeaBaby:
I looked at the arms and decided that the threads are to close to the edge, but as Ive never actually broken any I wanted to check the failure modes.
Ive had a look and I dont think Ive got any alloy thats 3mm thick, but I do have some steel, I might knock up a trial one in 3mm steel and see how much extra it weighs :P
Cool on the Ti, Ive got sunday earmarked as a 'garage day', as SWMBO and the 2 year ols daughter are going out to an inlaws christening. My excuse is that I need to make some stuff for my heli :smokin:
Dave
psindrup
06-26-2008, 04:43 PM
Hi Dave, sorry for the delay sending the titanium. Its in the post so you should get it tomorrow or Saturday.
I'm not sure if you've seen this but Stoatnchips posted it a while back. If you can make the arms similar to this they should be far stronger than the originals. The ones I've trashed have all bent at the threads. Basicaly, theres not enough material around the screws. http://www.helifreak.com/attachment.php?attachmentid=47598&d=1210359804
That looks really really good! :thumbup:
Peter
J-Heli
06-26-2008, 05:38 PM
Put me down for some titanium See Saw arms. Thanks for taking the time/effort to do this.
small.planes
06-29-2008, 01:10 PM
Whilst Im waiting on the correct coolent for machining the Ti (quite important so I understand) I decided to figure out how to make these things :)
After a proper look about I found some 3mm alloy, so heres some pics of the progress so far. Ive still got to make the jigs for shaping them to a more seesaw shape, and weigh them, but they should be much stronger than the existing ones, even not made from Ti.
Probably start taking orders for alloy ones middle of the week I think, if theres any interest.
Dave
Buzzkill
06-29-2008, 01:20 PM
Hell yes !!! Just get rid of the rectangle and put me down for some! Very Very cool :thumbup:
Jetleaf
06-29-2008, 11:57 PM
+1 I'm interested :thumbup:
J-Heli
06-30-2008, 12:00 AM
Me too. :thumbup:
psindrup
06-30-2008, 08:25 AM
Probably start taking orders for alloy ones middle of the week I think, if theres any interest.
Dave
+1 - and you don't even have to mention the price. :cheers
Peter
northcarolinadan
06-30-2008, 09:13 AM
I"m in for a set....:thumbup:
Mark me down for a set also.
Dave
brandon_8
06-30-2008, 11:45 AM
Me too!
stoatnchips
06-30-2008, 01:38 PM
Dave, i'm sure you checked my measurements... its the best i could do with the digital tools i had. I put these sketchs together quickly just as a way to indicate where the arms needed to be beefed up. Please fully check everything before you start taking orders and test fly.... Then i'm in for a set too :) The geometry is the only important part IMHO... weight differences will change the mixing response but i don't think any of us will notice it! Thanks again for the effort:thumbup:
Just as an after thought... you could make a Cross shapped pair or arms.... or 6 pointed star...
the standard 2:1 mixing ratio would use holes at 3.5 & 7.0 centres as the original Gaui ones do...
then another pair at 2:3 ratio with centers of 4.0 & 6.0mm
and maybe finally a pair with 3:4 with centres of 4.5 & 6.0mm
they would look like tiny servo horns that you could rotate by 60/90 degs, and move the balls around to tune the head.
scarr
06-30-2008, 03:42 PM
Just had a minor crash and the only thing broke is a pulled out and missing ball from the See Saw... So another vote for a set here also.
small.planes
06-30-2008, 06:15 PM
Ok, Jig made, heres the first set of seesaw shaped ones :) I actually scrapped 4 making the jig right (picture is of one which smacked me in the face on the way across the garage, lucky I had my visor on:wow2:). I hope to refine the shape a little after Ive made a few, once I get a feel for how much more can come off.
Stoat, I checked the measurements, and the holes on this one line up with the one I took off and checked it against. If you want different ratios then thats no problem, but I dont think a star shape would be easy to make. I can make this shaped ones in any ratio you'd like (within reason, it still has to fit...) Custom mixers anyone? :thumbup:
Weight wise they weigh about 0.4g, the existing ones weigh about 0.08g. I say about, as the slightest breath makes the scales vary by upto a gram or so...
Ill be selling them as a pair of alloy bits, and stainless cap head bolts to attach the balls with. I cant get bearings at anything like a sensible price, but crashed people and upgrades should be able to use their existing ones. Price to be confirmed, but I expect it to be about £12 (GBP) a set including shipping (airmail letter probably, or first class for inland UK). I have paypal so thats probably the easiest way of ordering.
Dave
crabfu
06-30-2008, 06:23 PM
Looks awesome... beefy as heck :) And glad to hear that it didn't take your eye out!
-Crabfu
Buzzkill
06-30-2008, 09:17 PM
Glad your ok, Let us know when your taking orders!!! :thumbup:
small.planes
07-03-2008, 04:54 PM
Ok, refined the jigs a little and heres the newer version. Ill start to take orders now, but it'll be about a week for me to start shipping I think, as Im away at the weekend. (Ill try and get them done sooner)
To order send £12 (GBP) per set by paypal to david.sanderson4@ntlworld.com
Let me know you want the mixers and where to send them, and Ill make them and send them out. Ill be sending them first class inland UK and Airmail to the rest of the world.
The kit is 2 alloy mixer arms and 4 stainless M1.4 bolts to bolt on the balls. You use the existing bearings and bearing bolt to attach them to the blade grip arm.
Ive got a plan for the (now fragile looking) blade grip arms :thumbup:
Dave
SurfCity
07-03-2008, 05:05 PM
Nice. What's the weight difference on these things?
small.planes
07-03-2008, 05:20 PM
Just been and weighed them: Original Gaui arm and 2 short Gaui screws :0.15g, new arm and 2 longer screws 0.55g, so about 0.4g per side heavier, or just under 1g total.
The arms are milled to shape in pairs to ensure (as much as possible) that they are balanced, even if there are slight variations between sets.
Dave
northcarolinadan
07-03-2008, 05:48 PM
Sent to you ! ! !
I am looking forward to them !!
thank you !:noteworthy and the Goooie thanks you too !!
Ok, refined the jigs a little and heres the newer version. Ill start to take orders now, but it'll be about a week for me to start shipping I think, as Im away at the weekend. (Ill try and get them done sooner)
To order send £12 (GBP) per set by paypal to david.sanderson4@ntlworld.com
Let me know you want the mixers and where to send them, and Ill make them and send them out. Ill be sending them first class inland UK and Airmail to the rest of the world.
The kit is 2 alloy mixer arms and 4 stainless M1.4 bolts to bolt on the balls. You use the existing bearings and bearing bolt to attach them to the blade grip arm.
Ive got a plan for the (now fragile looking) blade grip arms :thumbup:
Dave
Buzzkill
07-03-2008, 05:49 PM
Just been and weighed them: Original Gaui arm and 2 short Gaui screws :0.15g, new arm and 2 longer screws 0.55g, so about 0.4g per side heavier, or just under 1g total.
The arms are milled to shape in pairs to ensure (as much as possible) that they are balanced, even if there are slight variations between sets.
Dave
Those look great! $24 isn't a bad price at all figuring the time you'll have into each set. Especialy knowing they'll outlast the stock crappy see-saws.
Thanks for taking the time and effort to us all out. :thumbup:
Who's gonna be the first to crash test these things?
Those look great! $24 isn't a bad price at all figuring the time you'll have into each set. Especialy knowing they'll outlast the stock crappy see-saws.
Thanks for taking the time and effort to us all out. :thumbup:
Who's gonna be the first to crash test these things?
I AM the official crash tester, and I intend to do my job, with gusto(?). :roll:
Dave