Go Back   RCCrawler Forums > RCCrawler General Tech > Newbie General
Loading

Notices

Thread: vp hurtz shifter dig

Reply
 
LinkBack Thread Tools Display Modes
Old 08-01-2009, 01:23 AM   #1
Rock Stacker
 
Join Date: Jul 2009
Location: 96782
Posts: 62
Default vp hurtz shifter dig

im using an old ko propo mars ex-1 remote that has a 2 position switch. how do i set trim setting for vp hurtz shifter dig. i fried my servo for dig already and dont want to fry another.
808toys is offline   Reply With Quote
Sponsored Links
Old 08-01-2009, 03:35 AM   #2
tjb
Rock Crawler
 
Join Date: Apr 2006
Location: Eau Claire
Posts: 776
Default

You set it up for dig and 4wd... You will not have free wheel, which is no big deal..

Don't set the throws with the linkage (servo horn) connected. Ease your throws and put the servo horn on to check them, that way you don't fry it with too much throw..
tjb is offline   Reply With Quote
Old 08-01-2009, 03:57 AM   #3
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

If your Mars EX-1 is the same model as mine, it doesn't have adjustable end points (EPA) on channel 3.

You've got 4 choices:
Find a servo arm and linkage that are exactly the right length.
Get a digital servo and matching programmer. You can use the programmer to set the EPA directly on the servo.
Get a new radio with EPA on ch3.
Build a new radio, using the Mars case and the electronics from a 6-channel airplane Tx. There are several threads on the electronics forum about building Txs.

Another option that might work is a Punk RC dig switch. No idea if this will work properly with the standard Mars, because it's only got "soft" momentary buttons for ch3.
clockworks is offline   Reply With Quote
Old 08-01-2009, 04:16 AM   #4
Rock Stacker
 
Join Date: Jul 2009
Location: 96782
Posts: 62
Default

how would i know what the exact lenght and servo horn to use
808toys is offline   Reply With Quote
Old 08-01-2009, 04:18 AM   #5
RCC Addict
 
Join Date: Jul 2006
Location: Pasadena
Posts: 1,118
Default

or you could add potentiometers to each leg of the switch. this will allow you to adjust. that is, if it works like a TQ3.
danielk is offline   Reply With Quote
Old 08-01-2009, 04:24 AM   #6
Rock Stacker
 
Join Date: Jul 2009
Location: 96782
Posts: 62
Default

whats the easiest way and cheapest fix for now, i was planning on getting ko propo ex-5ur in couple of weeks when they come in. thanks for the help by the way
808toys is offline   Reply With Quote
Old 08-01-2009, 04:25 AM   #7
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by 808toys View Post
how would i know what the exact lenght and servo horn to use
Trial and error. Start with a very short arm at the servo end of the linkage, being very careful to make sure that the servo doesn't bind at either end. Keep increasing the servo arm length (or decreasing the dig arm length) until you get full movement at the dig, without the servo locking up. Adjust the linkage length to balance the servo between the 2 end points.

Not sure if adding EPA pots will work with the Mars. It doesn't have a dedicated switch for ch3 - you have a choice of 2 switches (maybe 3?) and you program the Tx with your choice. If this switch is just a logical signal to the microcontroller (which it likely is), adding pots won't affect the throw.
clockworks is offline   Reply With Quote
Old 08-01-2009, 07:54 AM   #8
RCC Addict
 
Join Date: Nov 2006
Location: Lowell, Arkansas
Posts: 1,307
Default

or you could get one of these.... It's what I had to do with my JR Z-1 / KO Helios

http://www.servocity.com/html/180o_servo_stretcher.html

They are a bit fiddly to get set up, but they work.
Manning is offline   Reply With Quote
Old 08-01-2009, 08:12 AM   #9
Rock Crawler
 
Join Date: Feb 2008
Location: UK
Posts: 818
Default

Quote:
Originally Posted by Manning View Post
or you could get one of these.... It's what I had to do with my JR Z-1 / KO Helios

http://www.servocity.com/html/180o_servo_stretcher.html

They are a bit fiddly to get set up, but they work.
Wow - an adjustable stretcher. Not seen one of those before here in the UK. Useful piece of kit.
clockworks is offline   Reply With Quote
Old 08-02-2009, 02:14 AM   #10
Rock Stacker
 
Join Date: Jul 2009
Location: 96782
Posts: 62
Default

got linkage almost perfect but when i engage dig servo still can turn about 1/16.



i want to throw my truck against the wall already
808toys is offline   Reply With Quote
Old 08-02-2009, 09:07 AM   #11
Pebble Pounder
 
Join Date: Apr 2009
Location: Renton
Posts: 171
Default

You really should have a remote with end point adjustments. That would save you all the headache you are facing now.

For my Hurtz Dig, I have my 4WD end point adjusted so that if the engagement points are exactly aligned, the servo is still pushing it forward until I drive slightly and then it locks in to place and then the shifter rests a mm or 2 from the edge of the dig case. For my RWD Locked (all the way back on the shifter), I adjusted it so it would only have a light force on the servo if the engagement points are exactly aligned, thus, when I drive slightly, the rears will lock into place fairly easily since they aren't powered and rely on the dragging action to make that final engagement. I only have a 2pos 3rd channel on my radio as well, though I have end point adjustments on that channel. It took me just a few minutes to get it tuned in a working the way I like.

Not sure if this helps or not... Also if you are in the market for a new radio, keep an eye out for the new Futaba 3PM-MX that Harley showed off in the electronics forum here. If you are getting into digs on your crawler, a good radio is a must IMO. My JR XS3 has seen it's time for me, and I am ready to make the change to a nice 2.4Ghz system, like the 3PM-MX.

SS
salmonshark is offline   Reply With Quote
Reply



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 04:01 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2014 RCCrawler.com