thanks for the tip Steve, after looking at it again I think you are right about the binding under side-load. I will have a poke around for a better lazy susan, if there's no joy there I will look at the bearing solution
cheers Ben On Jun 22, 1:06 am, Steve Tyng <[email protected]> wrote: > Cheap lazy susan's aren't very good at taking a side load. When you > say you can spin the assembly by hand are you replicating the side > load your belt is applying to the bearing? If you do you may find it > binding. I used a lazy susan in T047 (but didn't get any good pics of > the rotate setup). To keep the lazy susan centered I built a drum > assembly that was attached to the lazy susan bearing that extended > into the tank. Rollers where attached to the underside of the top of > the hull which kept the assembly centered. The lazy susan bearing > bore the weight of the turret and the rollers kept it centered. This > pic shows the drum. > > http://rctankcombat.com/tanks/T047/07photo-large.jpg > > Maybe Rob can take some more pics of Heidi and upload them to the site > for a better visual explanation of how Heidi's turret swings. It's a > really cool setup! > > If side-load binding is causing your problem I'd suggest adapting a > bit of Cromwell tech to fix it. Install a 1/2" bolt at the center of > rotation on your turret base plate that extends into your hull. The > bolt will run through a bearing attached to the underside of your > hull. Your belt sprocket then attaches to the bolt. Something like > in this pic: > > http://rctankcombat.com/tanks/T040/13Cromwell041-large.jpg > > In fact, if you do something along these lines you will not have to > attach the turret to the lazy susan bearing, it would only sit on top > of it. > > Steve Tyng > > On Jun 21, 1:56 am, Ben Holko <[email protected]> wrote: > > > > > I started to build the turret and traverse this weekend, and it didn¹t go so > > well. > > > I cut out the base plate for the turret, and the top hull plate that it will > > sit on. A 12² lazy susan provides the bearing, the base plate and top plate > > get bolted to that and all was well with that. It had a little more > > resistance than I had thought it would, but I guess the bearings in these > > cheap lazy susan¹s leave a bit to be desired. > > > I have a 12v geared motor from surplus center > > (https://www.surpluscenter.com/item.asp?UID=2009062005294011&item=5-16... > > ame=electric ) which I am using (trying) for the traverse. Together with > > some mini timing belt components from Small Parts Inc (via Amazon). Problem > > is however that the motor doesn¹t seem to have enough grunt, and the weak > > point in the link is the timing belt components, the belt is jumping teeth > > on the sprockets. > > > I have reviewed all the build pages on the tanks which detail their traverse > > systems, and have gained little further inspiration. According to Surplus > > Center this motor has 48 lb-in of stall torque, most other motors I see have > > far less than that, can anyone weigh in with the bearing/drive/torque > > combination that they have found success with? > > > PS: also hacked up the exhaust armor guards > > > Exhaust Guards 01.JPG > > 252KViewDownload > > > Exhaust Guards 02.JPG > > 324KViewDownload > > > Traverse Failure 01.JPG > > 184KViewDownload > > > Traverse Failure 02.JPG > > 210KViewDownload > > > Turret Base.JPG > > 196KViewDownload --~--~---------~--~----~------------~-------~--~----~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to [email protected] To unsubscribe, send email to [email protected] Visit the group at http://groups.google.com/group/rctankcombat -~----------~----~----~----~------~----~------~--~---
