DEPS (was RE: MK Dual Elavator)

[Scott Smith]

DEPS is hands down the best elevator system in my opinion.  Also, I would
like to thank Troy for all his efforts in getting out a very nice, complete
setup.  However, I think it can be made better with the Teflon sleeves.

I'm doing two Central installs in a couple Patriot roaches and I'm a little
disappointed with both installs.  Neither are as friction free as last
year's CST kit.

I had the luxury of installing these while the fuse was still an open box.
My support sleeves are about 21" long and I'd say you could measure the bend
at the halfway point at less than a 1/4".  The push rods hit the center of
the MK arms on the elevator (I haven't cut them to length yet.)  For all
practical purposes, they are straight and dead on to the horn.

Yet there seems to be a lot of friction that needs to be overcome to move
the assembly.  Once moving, it moves easily.  As such,  I'm concerned about
centering.

I was happy to see the graphite has worked for others and it may be just the
ticket.

  -----Original Message-----
  From: discussion-request at nsrca.org [mailto:discussion-request at nsrca.org]On
Behalf Of Troy A. Newman
  Sent: Friday, February 04, 2005 3:32 PM
  To: discussion at nsrca.org
  Subject: Re: MK Dual Elavator Bellcrank & Pushrod?


  Brian,

  sorry to hear you had some trouble with the guides on the DEPS.  We worked
pretty hard on getting the system to be  easy to install and friction free.
You are correct that any bending or curving in the system will cause it to
bind up as stated in the instructions for the DEPS.  The Teflon sleeves have
their own problems and what was happening is guys would wind the thread too
tight on the Teflon sleeve and crush it. This would cause friction points
along the length of the Teflon guide even it was dead straight. So the hard
plastic guide kept this from occurring.

  The key to both system is getting the pushrods at a straight shot to the
control horns. NO bends no curves. If you install it this way it will be
friction free. The right fuse exit location is so very important. I use a
4ft long straight edge to connect the dots from the servo connection
location to the elevator control horn. I do this on both the side of fuse
For the vertical location and angle and then the belly of the fuse for the
fore and aft exit location. I use masking tape and project the lines to
where I need to dremel the slot.

  This exit location will be very different depending on the location of the
elevator servo up front and will also depend on the width of the fuse at the
tail and where the elevator control horns are. So you need to have both
mounted so you can align the rods to pass right by the connection points. No
bending them over to it.

  A rough idea is my Supremes' have the exits about 10.5" forward of the
elevator hinge line. A narrow fuse like a Focus of Temptation this exit will
be slightly back further. The key is getting the slots in the right spot so
it doesn't bend.

  NOW some solutions I have heard of and never tried. Take the pushrods and
slightly sand them with some 320 grit. "roll" the rod in your fingers....The
ideal is not to sand diameter down but sometimes the pushrods can have some
ridges on them from manufacturer. I think they are Pultruded (sp?) and this
can cause some slight imperfections in the surface but I'm not sure.   I
have seen  a  few of these with the CST rods. Never caused me any problems
but I can see if the guides are curving it could.

  Next a little messy perhaps at first...Graphite dry lube like pine wood
derby wheel lube works pretty good. Squirt a little in the tubes and the
then install the pushrods. I heard of a guy doing this and he said it made
all the difference. If you have to remove a glue joint on your pushrods to
get it apart just heat the metal fitting up with a solder iron or a Bic
lighter the glue will soften and you can remove the fitting. A little sand
paper on the end where the glue was and the pushrod system will come right
out of the guides from the front. Then deal with the guides and glue the
ends back on. I recommend clean the old glue out of the hole. I use a
drill...but be careful the titanium ends are very tough and you can break
off a drill bit if you are trying to remove metal. I then use rubbing
alcohol to clean it. Dry with a bic lighter and then glue it on again. Works
fine.

  Next is sometimes you can get paint and crud in the tubes at the exits and
this will cause some binding. Clean out the exit tube with a small round
file....I have even used a long 2-56 pushrod threaded on one end to plunger
the tubes and clear some debris.  I even saw one where the guy used some
Thin CA to attach something and it ran down the CF rod and into the sleeves.
It didn't glue it in place but it did cause quite a bit of binding.


  I have not heard of guys having problems. Usually all you hear form this
list and RCU is the bad stuff and rarely does the good comes through. I get
tons of emails from guys that love it. I wondering if you try some of the
fixes above and they solve your issue. I just installed this system on
friends Angel Shadow and it works great! By the way Exits on it were about
11" forward of the elevator hinge line and they are a straight shot servo to
the control horns.


  As for weight I just stuck the plastic tube guides on a scale and the
Teflon guides as I have both. The Teflon one 4ft long was 6grams The Plastic
one 40" long was 5grams....

  The 0.070" solid CF rods can't run unsupported for the length of the fuse.
They will bow up when put under load. But inside the guides they are stiffer
and more solid than any system I have ever seen or flown. This includes
cables, MK, Dave Brown Fiberglass arrow shaft( the black one is fiberglass
and not CF) And the CF rods  done like the Dave brown fork with a bushing
support in the back. and supports in the middle too. The elevators get no
differential between sides when under load and many of the other system do.
This was the whole reason for using the DEPS system. Eliminate differential
side to side and have a friction free slop free system that was light.

  Troy


    ----- Original Message -----
    From: Brian Billings
    To: discussion at nsrca.org
    Sent: Friday, February 04, 2005 11:33 AM
    Subject: Re: MK Dual Elavator Bellcrank & Pushrod?


    Speaking of the CF push rod set ups, I would like to share a little
info. I just finished installing my second CF. elev. pushrod assem. in a
Impact, the first was in my Majestic. In the Majestic I got the DEPS setup
from CST seen here http://www.cstsales.com/CCPush-rodKits.htm
    This kit comes with a thin walled Teflon outer case and even with a
slight bow or arc in the assem. the system remains Very friction free.
    For the Impact I purchased the kit from Central and it comes with
plastic outer cases and these were difficult to get smooth and friction
free, the slightest bend or arc made the movement very stiff and as a matter
of fact, I could not even use them and ended up using hollow CF. rod for the
outer case which worked very well but slight bends or arcs are out of the
question. Just my personal experience, yours may differ.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.f3a.us/pipermail/nsrca-discussion/attachments/20050204/2fbbeb46/attachment-0001.html