Sunday, November 2, 2014

HOW TO MAKE SPRINGS by Dave Silberstein

Until a few years ago, Dave Silberstein maintained a great site at EarthLink that delved into the mysteries of making springs. It was very extensive. If you needed to make a spring, his site helped you do it. He even went so far as to publish the site contents in book form at Sadly, both the site and the book are no longer available because Mr. Silberstein passed away in 2012 in a car accident.

Such a valuable resource should not be lost. Fortunately, the WayBack Machine of the Internet Archive has kept an archived copy.

Here's the site map so you can get an idea of what's available and also so the search engines will pick it up.


Introduction Disclaimer, preface, description of the main types of springs
Design General principles, mathematics, design limitations, buying design
Materials Types of wire and their attributes, buying wire
Safety General safety, wire handling, opening and closing coils, coiling safety, wire storage
Equipment Winding machines, drills, hand winders, lathes, grinding equipment, finishing equipment, ovens, passivating equipment, hand tools, testing equipment, tooling stock
Tooling Pickup pins, wire guides, looping plates and rods, layover plates, bending pipes, bending jigs, passivating baskets, grinding stages
Setup First coils, drill setup, hand winder setup, lathe setup, left-handed springs, coiling without a lead screw
Torsion springs Wire length, first trial spring, torsion spring ends, extended hooks
Extension springs Wire length, first trial spring, loops, hooks, swivel hooks
Compression springs Wire length, first trial spring, grinding the ends, squareness, free length adjustments, setting solid, heat setting
Finishing Tweaking dimensions, stress relief, passivation, plating
Other types of springs Buckling columns, nested compression springs, conical compression springs, variable-pitch springs, snap-rings, double-torsion springs, wire forms, bedsprings, limited-travel extension springs, braided wire springs, heavy wire, light wire, square and flat wire, tubular stock, leaf springs, Belleville washers, clock springs
Spring shops Organization, product costing and pricing, careers
Glossary Definitions of spring-related words, detailed diagrams of the major types of springs and their parts
Resources Sources of information, associations, spring shops, suppliers, and other related links
Credits About this site; about me; and how to download this site.
New stuff This is an index page that provides access to new stuff added since January, 2003, and a chronicle of updates to the main body of the site.

Here's the link to the entire website for HOW TO MAKE SPRINGS.

There is a slightly older version of the site available for download as a ZIP file.

A PDF version is hosted here.

Here's a site that describes a homemade spring coiler. And two more sites for similar tools: One, Two.

A YouTube video of a spring winder.

DI-ACRO made a spring winder that shows up on eBay once in a while. Other manufacturers have made and make spring winding tools as well.

Sean Michael Ragan has an informative spring-making site.

Tempering a spring.

Also an excellent, down-to-earth HOWTO site for spring-making is Randy Hengl's. He has an interesting approach to tempering the springs: burning them in motor oil.

Monday, February 4, 2013

My 15 minutes of fame. My '36 Auburn was mentioned in the What Are You Working On section of GEARZ.

Sunday, January 30, 2011

Cadillac Catera Power Seats

The exquisite, leather-covered power bucket seats offered by Cadillac for their Catera (a re-badged Opel Omega; the same platform was also later used for the Pontiac GTO) are a great value for the streetrodder. From 1997-2001, about 95,000 were sold in the USA. The leather seats feature 6-way power (driver and passenger; some are heated) and are made by Recaro. These are some of the most comfortable seats I've ever sat in and are frequently sold on eBay for $350 a pair .

Really? Just $350 for a pair of such nice seats? Why are they so relatively inexpensive?

The passenger seat is a conventional power seat with conventional relays and wiring. Wire up +12V and a ground and you're good to go. But the driver's seat uses solid-state relays and is connected to the car's main computer. As a result, many people believe that the seat won't work unless it's installed in a Catera and hooked up to the car's main computer. They are wrong.

All you lose by not being connected to the Catera's main computer is the three memorized positions that the main computer can store. Still, many people could not get the seats to work. The secret is all in the wiring, but the solution is hidden in the Troubleshooting section of the Cadillac service manual.

First, there are three +12V connections: two thicker wires and a thin wire. The thicker red ones (#1 & #3 in the service manual) are connected to an always-powered source. The thinner red one (#4) is connected to an accessory-powered source. The brown wires (#2 and #5) are the grounds. The data control wire is #6 and is not used. The secret wire is #7, a thin grey wire. In the Catera, this is connected to the door switch that controls the courtesy lights. When this wire is not grounded (when the door is open), the seats will not move. I just grounded it permanently; it seems the GM engineers did not want you to move the seat with the doors open. It's also important to wire #4 to a circuit that is hot only when the engine is running or it will drain the battery. That's all there is to it.

There are only two drawbacks to these seats. First, the Catera was four-door car, so these seats will not fold forward. If you used them in a two-door car, you won't have access to the rear seats. Second, they are wide, so without some modification to the seat cushion and re-covering, they are not useable in most 30's-vintage cars.

But if they fit (or can be made to fit), you will have some sweet, comfortable Recaro 6-way power seats for your ride for just $350.

Friday, May 7, 2010

Adlan Eagle Shocks

Aldan Eagle shocks have an excellent, well-earned reputation, but sometimes people get in the way.

My '37 Plymouth coupe uses a ladder-bar and coil-over rear suspension installed by the owner of Hunter's Hot Rods in Pennsylvania.

The shocks are red steel Aldans from about 10 years ago when the car was constructed. The coil springs don't carry the typical Alden paint ID so it's impossible to easily tell what the spring rate is; the shocks themselves have no model ID on them other than the Aldan logo.

The original builder did a poor job selecting the shocks and springs. The springs were sized incorrectly (too light), as were the shocks themselves (too short as I later discovered) with the end result being the shocks would constantly bottom out, especially if I had any luggage in the trunk. Needless to say, the ride quality was awful and I decided to have the shocks re-built and get the appropriate rate springs (which I calculated to be 400#).

I went to the Aldan web site and sent them an email giving the specs of my installation and requesting a quote for re-building the shocks. Rather than an email address at, their email address used the NetZero domain. NetZero is a free-to-low-cost dial-up ISP. That should have been my first warning something would go awry.

After a few days, I received an email from Ferrel Alan of Alden Eagle which asked me to call him at the business number. Why give an email contact if you prefer to do business over the phone? Oh, well.

We discussed my needs and I found him to be very knowledgeable and helpful. He suggested a shock that was physically longer than what I had and he agreed with my calculation on the spring rate. He also suggested that I use flexible bearings in the upper mount vice the standard rubber bushings because of the front-to-back movement of the shock due to the ladder bars. He then asked me for the mounting stud size and I could not find my notes and was not near the car. I later emailed the measurements to him.

When we did get back together by phone, Ferrel seemed to have a difficult time recalling our conversation and did not have the stud size info, so I provided it again (5/8" top and bottom), asked that he add an ALD-20 shock spacer to the order and provided my credit card information. He shipped the shocks after I made a follow-up phone call to see why they had not yet shipped: "They went out today".

When they arrived, the bearings were not included, nor were the ALD-20 mounting spacers that I ordered. When I spoke with Ferrel, he apologized and sent the bearings without additional charge but suggested that I contact the manufacturer of the spacers, Paul Horton of Welder Series in Canada, since Aldan did not have any in stock. I did as he suggested and everything arrived in a few days.

When I went to install the bearings, I discovered that the bearings only accommodated a 1/2" stud, not the 5/8" stud I had. I called Ferrel who said that the 1/2" bearing was all that would fit in the shock without extra machining and suggested that I contact Horton's or SpeedWay Motors to obtain a 1/2" shock stud. I have to wonder why he didn't tell me all that to begin with since he had the stud sizes?

The shocks are now mounted and the ride is great, but I'm left in amazement at the customer service that Aldan's provided. The process should not have been so haphazard, drawn-out and frustrating, but maybe I should have expected nothing less from a business that uses NetZero to get their email.

Saturday, September 5, 2009

Older Holley 4150 and 700R-4 TV Cable Problems

I'm in the process of mocking up my re-built Chevy small-block to find unanticipated problems and have been very successful: I've run into a big problem.

I'm using a Weiand 142 blower "kit" P/N 6500-1 and Weiand's recommended Holley carb, P/N 80572 (it's a boost-referenced Holley 4150; tech info can be found here and a HOWTO on modifying one can be found here).

The problem is that I'm also using a 700R-4 transmission and the Holley carb, according to the instruction manual, " ... is NOT designed for use with ANY automatic overdrive transmissions." (Of course, they only disclose this in the installation instructions; it's mentioned nowhere else. Farging bastages.) This incompatibility with an AOD is my big problem.

Obviously, what they are really referring to is not a Hatfield-McCoy (or PC-Mac) kind of incompatibility, but the lack of any appropriate bracketry associated with the throttle cable attachment point so that a TV cable can even be attached. This also means that Holley's "solution" (P/N 20-121, their 700R-4 kickdown throttle bracket) has NOTHING to mount to. Even if it did (and have one), the geometry is all wrong, only pulling the TV cable through a 30 degree arc instead of the required 78 degrees. That may be why others have had a problem with their 700R-4s even when using the Holley bracket.

Working from info at Sumner Patterson's site, I found I could modify/construct a bracket to add the 700R-4 functionality that Holley left out. You'll need to construct a diagram of the sweep of the TV cable stud following the drawing, but Sumner's directions weren't clear to me at first. You'll need a compass, a protractor and a ruler that reads in 1/10ths of an inch. The TV cable stud moves in an arc whose center is 1.094 " to 1.125" from the throttle shaft center. From closed throttle to WOT (wide open throttle), the arc is 78 degrees. First, mark a point on some card stock; this is the center of the throttle shaft. Draw a vertical line through this point. Set our compass between 1.094 " to 1.125"; Sumner used 1.1" which is about the middle of the two and draw a circle. This circle represents the arc that the TV cable stud follows. Using your protractor, make a line 55 degrees from the vertical line just like in the drawing. Now make another line 78 degrees from that just like in the drawing. One reason the drawing is confusing is that you'll never see the cable sitting on that vertical line; that's just used as a reference to get the other lines drawn in the correct location. To finish, make a horizontal line at 90 degrees to that vertical line about 1.25" below the shaft center point. That horizontal line must be held parallel to the bottom of the carburetor. Cut the card stock like Sumner shows here and read his detailed version of the process here.

To work through the details, I constructed a piece of card stock with the correct geometry , located the correct placement of the TV cable stud, and mocked up a solution. I noticed that the Holley bracket, if installed according to their directions on a newer 4150 carb that has an extended bracket will not track the correct geometry. I will simply cut up the otherwise-useless Holley 20-121 bracket and welded it to the carb in the appropriate place. Based on my mock-up, the TV cable stud will move through the correct geometry from closed to WOT. In theory, I've solved my problem, but there's a lot more to understand.

It's also important to position the TV cable bracket at the back of the carb correctly in relation to the stud on the carburetor. The distance will vary because there are different length cables in use. The way to measure yours is detailed here. The cable needs to run parallel to the base of the carb as well. My next step is to modify the bracket I have to get the correct location. No one said this was going to be easy, but and improperly installed cable will ruin your 700R-4 in short order.

There's a good overview of how the 700R-4 throttle valve works here. A nice FAQ about the 700R-4 here. And a speedometer gear calculator for both the 700R-4 and 200-4R here. It seems the best way to check if your 700R-4 is adjusted correctly is to hook a pressure gauge up to it and observe the readings from idle to WOT. BowTie Overdrives provides a PDF document describing the installation and setup of a 700-R4 or 200-4R transmission plus info on measuring for a driveshaft and wiring a lockup switch and brake relay switch. They recommend a 0 to 300 PSI gauge and 7 feet of hose and a 90 degree 1/8" NTP fitting. The pressure gauge is attached to the direct pump pressure port on the driver’s side of the transmission which is about 3-1/2" above the manual shifter shaft. They don't provide the "full Monty" of the test (or the pressures), but do offer a briefer "field test" on pages 16 and 17. The suggested pressure is 65 to 80 lbs at idle for either transmission; too high a pressure at idle will start you in second gear; too low a pressure will cause it to slip. The pressure should spike when you leave a stop light and if it doesn't, the tranny is slipping. A good discussion is here.

I used the "standard" method:
  1. Depress the adjustment button and collapse the adjustment sleeve.
  2. Releasing the button, move the throttle to WOT; the cable self-adjusts.
  3. Attain adjustment Nirvana.
You raise the pressure by pushing the cable adjuster back into the cable, preferably doing it a click or two at a time. What seems to be critical is the distance the cable travels from closed to WOT and doing it at a steady rate. That's why the geometry is so important; bad geometry moves the cable at an uneven rate and so varies the pressure at an uneven rate causing improper shifting and resulting damage. From "To raise throttle pressure (and raise shift points, and make "kickdown" more responsive) move the cable housing towards the firewall (away from the throttle linkage), as you simultaneously depress the button on the cable housing, move the cable housing away from the carburetor or (throttle body) to increase throttle pressure. Move the cable housing adjustment a small amount at a time (1 click or 1/16" or so), a small adjustment can often make a world of difference. Naturally, to lower the pressure (and lower shift points, and make "kickdown" less sensitive), move the cable housing towards the front of the truck.

Here is a good discussion of not only adjusting the TV cable, but measuring critical distances including the length of the cable itself.

You should always use a transmission cooler with a 700R-4 because heat is a killer for transmissions. The stacked-plate coolers are superior to the serpentine coolers. I always use the B&M #70264, rated at 14,400 BTUs; it's their biggest one. You can find stacked-plate coolers on Volvos in the wrecking yards. B&M also makes a fan-cooled remote-mount version, # 70297, but you should be able to fab something up for less that the $250 they sell theirs for. Ugh.

Problem solved; the transmission works great!

Thursday, April 30, 2009

Keeping Your Compressor Quiet

Air compressors are noisy machines. The two most commonly used ways to quiet them down are to locate the air intake outside (not good for the neighbors) or to build some type of enclosure with sound deadening material inside; that usually causes overheating problems due to poor circulation.

The best solution is to construct a silencer that uses the same principles as a gun silencer. But isn't that illegal? Only if you use it on a gun. We're using it on an air compressor. Still, this topic seems to be controversial, mostly by people who have a bury-your-head-in-the-sand approach to security and safety.

Here are the materials:

  • Pipe the same size the air compressor port will use, 16"-18" long.
  • Some exhaust pipe, the same length as the other pipe.
  • Some washers you have to make with a hole saw, enough to put one on each end and one every 1-1/2" that will fit around the air compressor intake port pipe and fit inside the exhaust pipe.
  • Steel wool to fit between the washers.
  • A drill and a 1/4" drill bit to drill holes in the smaller pipe between the washers.
  • A welding machine to weld the washers to the small pipe and to the large pipe at the ends.

Since the silencer will be heavy, use a 90-degree fitting and mount it vertically.

Some links to sites that describe how silencers work and how to construct silencers can help you understand how the Air Compressor Silencer is constructed. If you Google for "gun silencers", you'll find lots of sites, so we're not divulging secret, hard-to-find information and, unless you're dumb enough to build one for a gun, not breaking any laws. If you think so, the terrorists have already won and you are not thinking of the children.

What Pipe to Use for Your Shop's Compressed Air?

Many people use Schedule 40 PVC pipe and that choice is - OSHA ALERT - potentially dangerous. Under pressure, PVC can explode when it becomes brittle with age or exposure to UV light or when struck by an object. But there are a lot of shops piped with Schedule 40 PVC. If you choose to use it against all advice, at least consider the stronger Schedule 80 pipe and fittings, keep the pipe protected from things that may fall on it and don't hammer near it. PVC is smooth inside which means less pressure drop from friction.

There are ABS pipes, Dura-Plus and Chem-Aire, that are rated for compressed gas use. The cost is roughly twice that of Schedule 80 PVC. Dura-Plus comes in a metric size (colored blue) and an industrial size, colored gray; the blue pipe cannot be threaded for standard pipe threads. Chem-Aire pipe is green.

Schedule 40 black iron pipe is a popular choice and is very sturdy and durable. It's also heavy and awkward to install and will rust inside, not only adding scale to the air, but increasing friction and causing increasing pressure drops over time. Galvanized Schedule 40 is a better choice, but more cumbersome to work with and also requires some specials tools.

Copper pipe is lighter and easier to install, and comes in three types. Type L is identified with blue markings and Type K is identified with green markings; both are strong enough to use. Type M is marked red and is not recommended since it is only rated for 125 PSI; that won't leave much of a margin for error. Copper is smooth inside which means less pressure drop from friction; this matters for long runs of pipe.

Of course, you could always use stainless steel pipe and compression fittings or even the very cool (but ridiculously expensive) Garage Pak system which uses a coated aluminum pipe and special fittings. All that expense does buy a product that is easy to use.

There is also Compressed Air Systems which sells coated aluminum pipe. This looks like what I saw at Harbor Freight.