Front axle shackle mounting - Page 2 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Suspension - Brakes - Steering
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #16 (permalink)  
Old 05-24-2011, 10:19 AM
1ownerT's Avatar
Home School Valedictorian
 
Last wiki edit: Health and safety in the shop or garage Last photo:
Join Date: Dec 2004
Location: Iowa
Age: 53
Posts: 1,645
Wiki Edits: 4

Thanks: 0
Thanked 3 Times in 3 Posts
In my uneducated opinion B would be the stiffest. My thinking...The spring eye is behind the center point of the shackle and has to go "over" center before the shackles lay down. C- the spring eye is already past center and doesn't have to go over the hump.

If any of that makes sense.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #17 (permalink)  
Old 05-24-2011, 10:53 AM
cboy's Avatar
Member
 

Last journal entry: Finished
Last photo:
Join Date: Jan 2004
Location: Atwater, CA
Age: 69
Posts: 3,918
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 4 Posts
Oops. I posted the following image earlier but the post is not appearing in the thread.

I found this illustration on the web and it seemed quite helpful to me. It might help explain the situation with photos A,B and C above.



The source site for the above illustration also says this:

A good starting point for shackle angle is 90 degrees. In this position the shackle has no effect on spring rate.

Source I found the same illustration and conclusion on a number of different sites discussing shackle mounting.


If I understand this diagrame correctly, the shackle position in Photo "A" (in prior post) would have no effect on spring rate/stiffness because it is in the 90 degree position.

Photo "B" would soften the spring rate and soften the ride...at least according to the diagram.

Photo "C" would stiffen spring rate and ride.

Am I reading the illustration correctly?
__________________
Always learning...and sharing what I've learned. The Scratch-Built Hot Rod.
Reply With Quote Quick reply to this message
  #18 (permalink)  
Old 05-24-2011, 10:58 AM
cboy's Avatar
Member
 

Last journal entry: Finished
Last photo:
Join Date: Jan 2004
Location: Atwater, CA
Age: 69
Posts: 3,918
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 4 Posts
Quote:
Originally Posted by 1932bantam
yes it does look like it could work, I've looked at your work and I think you can build what ever you think will work. excellent stuff!!!!!!!
Thanks for the vote of confidence bantam...but I experiment a lot and have been known to screw things up quite badly from time to time. Lots of failures to get to the successes.
__________________
Always learning...and sharing what I've learned. The Scratch-Built Hot Rod.
Reply With Quote Quick reply to this message
  #19 (permalink)  
Old 05-24-2011, 11:23 AM
cboy's Avatar
Member
 

Last journal entry: Finished
Last photo:
Join Date: Jan 2004
Location: Atwater, CA
Age: 69
Posts: 3,918
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 4 Posts
Quote:
Originally Posted by 1ownerT
...If any of that makes sense.
Your explanation makes sense and my first thought is to agree with it. But perhaps the shackle in Photo "B" continues in a downward arc rather than reversing itself and rising up over the top of the arc. At least that is the message I would take away from the illustration in my prior post.

But then I could be reading the illustration incorrectly.
__________________
Always learning...and sharing what I've learned. The Scratch-Built Hot Rod.
Reply With Quote Quick reply to this message
  #20 (permalink)  
Old 05-25-2011, 07:48 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
Quote:
Originally Posted by cboy
Could a couple of you guys double check my assumptions here?

Based on the illustration in my prior post my analysis is:

In photo "A" below, the shackle position is 90 degrees and if this were under full weight, the shackle position would have zero effect on spring rate or ride stiffness.

When the spring begins to compress in photo A, the shackles will move outward where they are attached to the spring eyes. Total travel would be limited to the point where the bottom of the spring makes contact with the top of the lower shackle connection. I believe the ride would be OK with very little travel and will bottom out easily. The spring rate should be constant with this method. Side to side movement must be controlled. A panhard bar would help.

Quote:
Originally Posted by cboy
In photo "B" below, the shackle position would soften the spring rate and soften the ride.

In photo B there is a potential of the shackles binding as the spring attempts to spread wider. Another possibilty would be for one shackle to get moved to the extreme outboard position that would cause the other shackle to be moved to the extreme inboard position. This would result in a sudden extreme sideways movement that would appear to be very unsafe and difficult to control. This could be reduced somewhat with a panhard bar. I don't think in retrospect that this mounting would yield a safe or workable suspension as shown in the photo.



Quote:
Originally Posted by cboy
In photo "C" below, the shackle position would stiffen the spring rate and stiffen the ride.



Am I on the right track here?

(Pardon the shoes BTW.)
Once again, in photo C as the spring is compressed the ends move outward and the top point of the shackles will also move outward. The overall travel of the suspension is limited as to the point where the bottom of the spring hits the top of the lower shackle mounting point. This would cause the suspension to bottom out. I do not think the spring rate would be affected. The stiffness would be caused by the limitations of the travel of the suspension.

cboy, I really like that you "think outside the box" and you have built some very interesting and innovative rides. I am curious as to what your reasoning is to consider these methods of mounting the spring? Are you attempting to raise or lower the front end? Are you considereing a behind the axle spring mount or an above the axle spring mount? Single axle or split? Could you possibly attach a simple sketch of what you are considering?
Reply With Quote Quick reply to this message
  #21 (permalink)  
Old 05-25-2011, 08:47 AM
cboy's Avatar
Member
 

Last journal entry: Finished
Last photo:
Join Date: Jan 2004
Location: Atwater, CA
Age: 69
Posts: 3,918
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 4 Posts
Quote:
Originally Posted by Frisco
... Could you possibly attach a simple sketch of what you are considering?
Frisco, thanks for your observations/comments about the alternative shackle configurations.

Since finishing the sedan/delivery I have been on a quest to create the smoothest most comfortable ride possible. I have tinkered a good deal with my original "quarter elliptical" springs and have made some progress but when my good buddy 454 Rattler said he had an unused Speedway spring stack tucked away in his shop, I jumped at the chance to experiment with it and see how it might/might not improve my front suspension ride.

The mounting will have to be somewhat unique because of the twin I-beam axles. But the twin beams also eliminate the side-to-side axle movement you mentioned. No need for a panhard bar since the axles aren't going anywhere.

These pictures show the spring stack simply plopped down in the approximate position it would need to be in just to give you an idea if what I am fooling with. Thought the photos might be better than a sketch.





As you will note, the attachment point for the shackle stud will have to be directly behind (or in front - depending on which axle you are looking at) the axle. The spring will also be about an inch higher at the center of the arch in order to mount to my existing mounting pedestal.

One other constraint on the design is that I need to mount this spring without destroying or altering any of the existing mounting points for my quarter elliptical setup. If the cross spring doesn't work or doesn't improve the softness of the ride, I want to be able to put the quarter ellipticals back on.
__________________
Always learning...and sharing what I've learned. The Scratch-Built Hot Rod.
Reply With Quote Quick reply to this message
  #22 (permalink)  
Old 05-25-2011, 09:49 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
Quote:
Originally Posted by cboy
I found this illustration on the web and it seemed quite helpful to me. It might help explain the situation with photos A,B and C above.



Am I reading the illustration correctly?
This photo (drawing) above would be correct, but it should be noted that there is only one moveable shackle. The other end would be in a 'fixed' position. As a result, the effect you are trying to achieve is not quite valid with this drawing.

In your latest posting showing actual photos and an excellent explanation as to what you are considering; I'd say 'Go for it'. It appears to be very workable. Also, since the spring is located in the center and you are using 'split' axles, there (as you've noted) should not be any side to side movement. I do think that the shackles can still be mounted in the 'conventional' 45 degree angle to your split axles. Of your three examples, photo A may be the most workable with the split axles.
Reply With Quote Quick reply to this message
  #23 (permalink)  
Old 05-27-2011, 07:59 PM
cboy's Avatar
Member
 

Last journal entry: Finished
Last photo:
Join Date: Jan 2004
Location: Atwater, CA
Age: 69
Posts: 3,918
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 4 Posts
Quote:
Originally Posted by Frisco
...I'd say 'Go for it'.
Well. I went for it. And I'm chalking up my first round effort to "test run" since it appears I need to recalibrate a bit.

Here's one of the two axle mounting brackets (for attaching the shackle bolt to the axle). This bracket is make so it can be mounted on a temporary basis for testing. If it works, I'll later drill holes to attach it though the axle itself rather than bolting it together under the axle.



This second photo shows the bracket mounted on the axle and the spring attached. Note that this is mounting position "C" from the prior post and was the only position I could place the bracket so it would not come in contact with other chassis components.



The final pic shows the complete assembly. Note that this is the position of the shackle during assembly with the frame up on blocks and all weight off the spring.



The only problem was when I got everything assembled and let the weight of the car down on the spring, the frame dropped far too low. In fact so low I couldn't get the floor jack out from under the frame.

Tomorrow I will experiment with adding an extension piece to the top of the axle mounting bracket. I'll drill a couple of holes at various heights so I can experiment with attaching the spring bolt in different positions...thus raising the frame 1"-4" above the mounting hole I drilled in the original bracket. The only problem will be compressing the spring enough to get the bolt into the higher mounting hole. Haven't quite figured that part out yet.
__________________
Always learning...and sharing what I've learned. The Scratch-Built Hot Rod.
Reply With Quote Quick reply to this message
  #24 (permalink)  
Old 11-16-2011, 08:27 AM
Registered User
 
Join Date: May 2011
Location: michigan
Posts: 4
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Smooth Ride Suspension

I have never rode in a T Bucket Roadster. I have always wondered about the front suspension setup.

Are they a smooth and comfortable ride or can you feel every bump in the road?

The project I am designing I want it to have a nice smooth comfortable ride, since I am going to drive it everday until the snow comes here in Michigan.

Delta
Reply With Quote Quick reply to this message
  #25 (permalink)  
Old 11-16-2011, 09:51 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
Quote:
Originally Posted by deltafour1212
Are they a smooth and comfortable ride or can you feel every bump in the road?
Most front suspensions commonly used on T bucket roadsters (as well as Most Fords from 1928-1948) utilize a "buggy" style spring. Because of this, the ride is still a "buggy" ride.

On smooth surfaced asphalt paved roads in good condition the ride is acceptable. On concrete roads with expansion joints, you will feel every expansion joint. Potholes can be rough.

If a panhard bar is installed the side to side movement is reduced. The use of 'slider' type springs helps also.

I suggest you ask someone to give you a ride in one to make your own decision.

Personally, I like the ride.
Reply With Quote Quick reply to this message

Recent Suspension - Brakes - Steering posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
need help figuring out what parts I need for rear axle mounting matt167 Transmission - Rearend 1 03-15-2010 07:25 PM
Electric trailer brake axle mounting schnitz Suspension - Brakes - Steering 11 04-09-2009 09:57 AM
Front Shackle Replacement problem??? okeesignguy Suspension - Brakes - Steering 0 10-06-2007 08:29 AM
4x4 axle conversion ttb to solid front axle. Jared Transmission - Rearend 6 11-07-2005 08:50 PM
4-bar axle mounting points cboy Suspension - Brakes - Steering 12 11-30-2004 01:16 PM


All times are GMT -6. The time now is 11:13 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.