T-Rex 600 Quick UK Swashplate

Introduction

A few months ago, after several flights on my Align T-Rex 600N, I started to notice that my stock metal swashplate began developing some vertical slop. At first, I thought that it may have happen because of my flying style or maybe even a factory flaw of my swashplate but, after checking my friend’s machines at the field, they all revealed having the same problem. Curiously, at that time particular time, Align introduced a new 3D lightweight Swashplate but, after what I’ve seen on the stock one, I wasn’t too eager to further dump my hard earned money into the same company that should have fixed this problem from the start. On a side note, I just became aware on some public forums that the new and supposedly improved Align Swash is also starting to develop some slop after several gallons of fuel. Seems my fears were confirmed after all. I started looking for a third party replacement swash and I promptly came across QuickUk’s website. I have a long time experience with their products and, as it happens, I already own one of their swashes which I mounted two years ago in a Hirobo Freya 90. That particular swash has still no slop whatsoever so, after a brief exchange of emails between Budd and me, a brand new QuickUk unit was sent to me.

First Impressions

Well, what can I say? As soon as I opened the package I was marvelled by the beauty and design of the swashplate. I immediately went upstairs to check its specs and compare it with my stock Align swash plate (see technical details section). One thing that became apparent right away was the quality of the unit. I dare to say that just the lower bearing probably costs more than the entire Align swash. Not only is it beautifully machined but also brings major improvements over the stock unit so you can’t really call it just “bling”.

Technical Details

The QuickUk swash plate weights 12.5gr less than its Align counterpart, is roughly 3mm thinner (but still as strong or even stronger than stock) and possesses a greater cyclic throw (an increase of over 2 degrees at maximum deflection). One important change is that the swash geometry on the QuickUk unit is absolutely perfect. The inner swash balls align perfectly (in the vertical pane) with the outer balls, making the entire head assembly symmetrical and thus allows a greater vertical swash travel without binding even with full cyclic applied. As you can appreciate in the following pictures, the QuickUk swash also features 4 set screws that allows the user to tighten down the bearing if some slops should start to appear after heavy use (I never needed to do this procedure though as all my previous QuickUk swashes have yet to develop any type of slop even after several years of use).

 

 

 

Installation and setup

The installation of the unit is pretty strait forward. However, please note that it is not a plug n’ play item since the improved geometry and lower height will have an impact on the existing head linkages length. It is imperative that the user resets the linkages accordingly and setups the head from scratch. As you can appreciate from the next picture, I’ve included my own personal measurements which should only be considered as guidelines since every helicopter is a particular case and mine has currently a full metal head and also third party metal main bearing blocks which can move the linkage lengths a few hundreds off.

 

 

Another important point is that the user will probably need a ball reamer tool to resize the stock Align link heads. The QuickUk swash uses slightly larger linkage balls that may feel a little too tight (but guarantied slop free). I flew my helicopter for about 5 flights without resizing the ball links and even though I didn’t notice anything in flight, the squeaking links bugged me when cleaning and inspecting the machine. A ball reamer tool will solve this in about 20 seconds. Don’t overdo this procedure or you may end with some linkage slop.

 

 

Finally, after all is set and done, don’t forget to also recheck the radio setup, paying special attention to CCPM interactions as one should do with any 120 degree swash anyway.

Field Test

After the swash installation, mechanical and electronic setup, it was time to finally go out and fly the machine. This is usually a good time to perform the last tweak or two that may be required to achieve a hands free hover. As soon as I took off, I realised that no trim would be necessary as the 600N quietly sat in a steady hover without any drift. I was pleasantly surprised as I always had to perform minor corrections on the stock swash setup. I now realise that this was probably due to the increasing slop that the stock unit was developing. As the flight continued, I also noticed some other interesting things. For instance, the control now felt much more precise and locked in. Small corrections were now a breeze and the helicopter seemed to obey precisely and effectively every single stick movement. All in all I was thrilled with the improved response.

Final considerations

After having flown over 100 flights with the QuickUk swash, I can now honestly report that there is absolutely no slop whatsoever. The swash feels like the day I installed it. This just confirms what I already experienced with my other QuickUk swashes. They just work! For those that are still hesitant because of the apparent higher price, my advice is: “Just get one and try it out. You won’t regret it”. The swash will pay off in time as one will not need to constantly buy new swashes to get rid of the developing slop. I also learned that QuickUk is about to release an improved washout block which is not only lighter but also has slightly narrower guides to remove additional slop that exists around the head’s axis induced by the relatively large guides of the stock unit. I wish Budd at QuickUk would go even further and design new washout arms, mixing arms, seesaw, etc. A full QuickUk head would be really something impressive to see and fly.