It started when I noticed a wobbling spindle pin. A worn hole at the bottom of the axle was letting it move about. "No big deal," thought I, "I'll just put in another axle." So I went out to the barn and found one, turned the perches red to get them out, then blasted and painted the axle. Today I got around to making the change. Removing the axle that was in the car went easily enough. Even getting the first perch out of it was easy. That's when things went south in a hurry. The second perch foiled all attempts with other methods, so I resorted to the twenty ton press. I put a nut on the threads to prevent mushrooming and applied the pressure. Here's what happened:
The perch moved about 1/8" and stopped. Adding more weight just broke the nut and squashed the perch.
So I need another perch. I thought I'd just use the one I took out of the "new" axle. Nope. Look at this.
The threaded part is too small. The nut just slips over it. No turning required. So now I have to find a perch of the right size. I probably have one, but I suppose it will be stuck in an axle.
I was unaware that perches for the under-the-axle wishbone configuration come in different sizes.
Steve,someone probably re-threaded it when it got worn out sometime in the past and used a washer.
Steve next time after you heat the axle, dunk it in a 5 gal pail of water and the perches will tap out with a hammer and you won't wreck your parts.
That is a really interesting idea. I'm going to be working on a axle soon. I think I might re-anneal it afterwards. Just me!!!
Well, I guess the old perch is ruined. With the threaded end mushroomed, it isn't going to come out the normal direction anymore.
Perhaps you can saw off the perch side and press it out the other direction (after soaking it in your favorite penetrating solution for a day or so)?
Be prepared for a big "bang" when it pops loose!
Perch might not be totally ruined. If you have a die that you can spread open, you might could get it on and then closed down to cut threads halfway up the shaft. Then just spin it off. Just an idea.
I have had more success with perch removal with a slightly different approach.
I use plenty of heat on the perch and the axle, think dull red. I have a 2' long bar machined to fit in the perch eye. This bar allows leverage to twist the perch in the axle. It takes repeated heats sometimes before the perch will move. Once is does, I work it back and forth, gradually freeing it up. Once I can move it freely, it can usually be driven/pressed out.
Hope this helps save some perches and angst!
Allan from down under.
After heating and a dunk bath, found the easiest way with a stubborn perch is to hammer on it left and right to twist it back and forth, that will loosen the stem for whamming it out of the axle.
Quench to shrink after heating with torch
Hammer out perch a bit, then hammer left and right to get it to twist.
Got that rascal!
I've heard these fights to get perches out can be legendary. Does anyone have a theory on why they stick so bad?
I think anti-seize compound is in order when reinstalling.
Easy theory....Steel perch post stuck into steel hole, normally tight nutted and cottered, perch taking on all the front spring load for 80+ years.
That axle always headlong into rain, sleet, snow, and mud.....think RUST
Some of us even add salt to the snow & sleet!
I did this job about a week ago. Years ago I had modified my 20 ton press with a pressure gauge so I can tell how hard it is pushing. One perch popped right out with only 1 ton of force. The other one took about 8 tons.... about 10 times. It would move about 1/16" and stick. Big bang each time.
Unfortunately the perch did mushroom a little on the end. That cleaned up in about 15 minutes with a carefully used thread file.
Next I used a wire wheel on my bench grinder and removed the surface oxidation from the perch and rubbed some axle grease on the shaft. Using a dead blow hammer both perches went almost all the way into the "new" axle. The nut finished the job.
I never used heat on the axle, I am glad of this since I plan on re-threading the old axle and don't want to weaken the forging. I am sure those perches will give me no problem in a few years when I am ready to swap the original '27 axle back in.
With the axle off the car, put the perch in a heavy duty bench vice and use the axle as a lever, moving back and forwards a little at a time. Eventually you will win the battle with no damage.
Took me a while to figure this one out.
When heating the axle do it inside out of the bright sun. You want to be able to see the axle as soon as it starts to turn dull red. That is the critical point of the steel. Any more than the dull red and things start to change in the iron. The redder it gets the more it changes. Another thing that helps is to use one of the "knock off" style wheel pullers. They are the type you screw onto the end of a axle and hit with a hammer to remove the hub. They make them in the size to screw onto the spring perch. I think Langs sells them. They work a lot better than a nut on the threads as they have more threads and also will bottom out to give a good push on the end of the perch bolt, instead of just the threads carrying the load of the press. I have also found that water is as good as penetrant when trying to get something like this loose after applying heat. You are trying to "wash" the threads clean of the rust that broke loose from the heat. If you use oil or penetrant it does not "wash" the rust out unless you use it like water and just keep flooding the part to "wash" it clean. and you stand the chance of "galling" the threads or in this case "galling" the spring perch shaft in the hole. Once something "galls" it is almost impossible to get it to move and usually destroys the part. I usually have about a 75% success rate on the "evil" perch removal jobs.
What Nevin said is what I always do.
I like that Nevin! Excellent idea.
That's what I've done also. What cause's the perch's to sieze or get 'stuck' is the rust or slight blemishing that occurs over time. It does happen.
The idea of getting a stuck shaft, T perch or something similar out of a piece of equipment, pump or in this case an axle perch will work a lot easier if you can turn the piece first back and forth. It will come out easier without destroying the piece or equipment your working on.
Being a maintenance mechanic many years I learned from the old guys who knew this trick from years of experience.
Then I realized those 'old guys' really did know more than I thought I did by beating, pushing and pressing!
You can weld on a new section of thread to an old perch. Just weld it close to the threads so the strain of the perch is taken by the original shank portion of the perch. Once it's welded and ground it will slip back in the axle and no one is the wiser. I've done it many times without incident.