Glenn,
You likely have one of these?
[
valleycustomrods.com]
You have a couple of options.
Go on line and buy a replacement spring from any source that sells spring of similar size.
Simply take a caliper and measure the diameter of the spring coil.
Use the caliper to measure the non stretched length of the spring.
Use the caliper to measure the diameter of the wire.
These three measurements will give you a pretty close match to what you need.
However, if your only problem is that the spring has stretched a bit, the fix is as follows:
Simply make the spring shorter. Use a good wire nipper to cut off about 2- or 3 coils of spring. Then, use a plier to sip over the end coil to form a new end for the spring. Reconnect the spring and it will be shorter and stronger.
Option #2
Take the spring and remove it.
Then, do that you need to do to be able to lock the arm in any position you wish.
If necessary place washers on each side of the rod rest vertical and horizontal members.
Then, either use the existing holes, or if necessary enlarge the holes with a drill to accommodate a larger fastener, or bolt.
Then, use a locking nut to tighten down the arm to a point where you can just barely move the arm up or down.
Then, when you go to use the rest, you simply lay the rod in its correct position with respect to height by adjusting the lower rollers, and then simply press down the top bar, until the rod is held securely.
For example from my own self built rod rests:
[
www.rodbuilding.org]
Click on the picture to enlarge it and observe the locking nuts on the horizontal arms.
Here is another entirely different design that uses two vertical rods to support the rod and support and retaining ars, using bolts to lock the rod securely in place:
[
www.rodbuilding.org]
This is a picture of my current rod rests:
[
www.rodbuilding.org]
Notice, that my lower support bar is adjusted and locked solidly by using a wrench on the bolt that makes the support bar secure.
The retaining upper bar with the single roller is held in place with a bolt and a nylon locking nut to hold the bar firmly enough to not move under use, but still allow a firm hand to lift and or lower the bar for rod placement and removal.
I have used these systems for my entire rod building career and have never had any of them fail or come loose with use.
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For your style rod rests, I would remove the spring and replace it with a bolt and locking nut and washers to hold the arm firm enough to hold the rod, but with a firm hand still be able to raise and lower the arm for rod placement and removal.
Best wishes.
