RC Radios, Transmitters, Receivers, Servos, gyros Discussion all about rc radios, transmitters, receivers, servos, etc.

Hitec 645 or 625 for Planes?

Reply

Old 06-13-2007, 11:33 AM
  #1  
tadatuo
Member
Thread Starter
 
tadatuo's Avatar
 
Join Date: Mar 2003
Location: Orygun, OR
Posts: 79
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Hitec 645 or 625 for Planes?

Hello,

Has any one used the hitec 645 high torque or 625 high speed servos for 1.60 size airplane applications? The torque is huge, but the product description says it is for helicopters and cars. Why not airplanes? Got a Great Planes Extra and Giles that I would like to use them in.

Thanks
tadatuo is offline  
Reply With Quote
Old 06-13-2007, 02:35 PM
  #2  
Ed
Senior Member
 
Join Date: Dec 2001
Location: Bemis, NM
Posts: 2,889
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

I am using the 625's in both giant scale gas, and glow powered planes.

> Jim
Ed is offline  
Reply With Quote
Old 06-13-2007, 05:25 PM
  #3  
aussiesteve
Senior Member
 
aussiesteve's Avatar
 
Join Date: Oct 2005
Location: PerthWA, AUSTRALIA
Posts: 2,924
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

I use 645MGs on a lot of my aircraft between 60 size glow and 50cc Gas - they are a bit slower than the 625 but there is never a concern about having enough Torque. Never had a problem with one (Damn - I shouldn't have said that).
aussiesteve is offline  
Reply With Quote
Old 06-13-2007, 05:41 PM
  #4  
sfsjkid
 
sfsjkid's Avatar
 
Join Date: Dec 2003
Location: fremont, CA
Posts: 592
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

Actually, Hitec lists the both for all applications (air to 1/4 scale, heli, and car),

http://www.hitecrcd.com/product_file/file/26/hs625.pdf
http://www.hitecrcd.com/product_file/file/28/hs645.pdf

Their master chart indicates the same though, heli's are not recommended.
sfsjkid is offline  
Reply With Quote
Old 06-13-2007, 11:20 PM
  #5  
XJet
Banned
 
Join Date: Mar 2003
Location: Tokoroa, , NEW ZEALAND
Posts: 3,848
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

The 645 is a great servo where price and torque are a prime consideration.

I use them on the ailerons of my 50cc plane and they're fine.

They are a little slow (too slow for my 40-100 sized profiles) but big planes respond more slowly anyway so you don't notice the slower speeds once you get up to 50cc (although I have HS5955TG servos on the tail anyway)

I haven't used the 625 servos though so can't comment on them but they are just the same electronics, case and motor with a different gearset so they should be fine.
XJet is offline  
Reply With Quote
Old 06-14-2007, 10:56 AM
  #6  
tadatuo
Member
Thread Starter
 
tadatuo's Avatar
 
Join Date: Mar 2003
Location: Orygun, OR
Posts: 79
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

Thanks for your replies. Seems like the best bang for the buck. I was comparing these to the digital counterparts by hitec.

Is it okay to mix digital and standard servos in one plane?

Thanks
tadatuo is offline  
Reply With Quote
Old 06-14-2007, 11:09 AM
  #7  
RobertC
My Feedback: (157)
 
RobertC's Avatar
 
Join Date: Mar 2002
Location: Kirkland, WA
Posts: 291
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

While there is nothing wrong with using either the 625 or 645 for planes, you should know that these servos have a history of "centering problems." They are strong and inexpensive but not quite as accurate as the more expensive digitals and coreless servos. I suspect that is why they are recommended more for cars and boats.
RobertC is offline  
Reply With Quote
Old 06-14-2007, 07:24 PM
  #8  
P-40 DRIVER
Senior Member
 
P-40 DRIVER's Avatar
 
Join Date: Apr 2005
Location: Cedar Park, TX
Posts: 1,623
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

How about the 5645 digital, $45 through Troy Built Models. Digital version of the 645 with better specs.
P-40 DRIVER is offline  
Reply With Quote
Old 06-15-2007, 08:30 PM
  #9  
XJet
Banned
 
Join Date: Mar 2003
Location: Tokoroa, , NEW ZEALAND
Posts: 3,848
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

the digital (5645) will give you better centering and holding power but whether it's worth paying the extra for this probably depends on your flying styloe.

If you're into 3D with large throws then the centering might be an issue -- but if you're more of a sports or simple aerobatics flier then you might not even notice the difference.

You *can* mix regular and digital servos -- I've got 645s on the wings of my 50cc Extra and 5955TG digitals in the tail -- no worries.

Another benefit of the digitals is their programability. You can change direction, throws, speed, etc -- which can make it much easier to set things up when you're running split elevators or multiple servos on a single control surface.

The problem with servos is that it's easier to find your self paying big dollars for the *best* because sometimes you tend to think like this:

1. Hmmm... a 645 should do ($35)
2. but... a digital 5645 would give better centeriing ($45)
3. yet, for just a a bit more ($70) I could go for a coreless motor too
4. and, if I'm going coreless, why not pay a bit more again for titanium gears and double the torque -- they'll pay for themselves by never needing new gears and besides, I can use them in much larger planes when I get one.

And before you know it -- you're spending $90+ per servo :-)

Remember, nobody ever regretted buying quality and, as you go up in price with Hitec servos, the quality seems to get better and better. Just stay well-clear of those Karbonite geared servos and you'll be fine.
XJet is offline  
Reply With Quote
Old 06-15-2007, 10:52 PM
  #10  
tadatuo
Member
Thread Starter
 
tadatuo's Avatar
 
Join Date: Mar 2003
Location: Orygun, OR
Posts: 79
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Hitec 645 or 625 for Planes?

Thanks XJet. Very good information there! I fly mild pattern, but hope to do some 3d stuff with my 1.60 Great Planes Extra so I'm leaning towards the digitals 5645. Hopefully I'll stop there on your thinking scale. Haha. Thanks again.
tadatuo is offline  
Reply With Quote

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


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service