The threads have been drilled out and a strip of bronze has acted as the threads on one of the spindle bolts on my front axle.
I would like make a proper repair to replace the threads. The best machine shop in Barcelona tells me they do not have any SAE threaded helicoils, but they will think something up. I was thinking they might machine a nut down and fix it in place where the threaded portion should be.
But before messing with all that, does anyone know how big the hole needs to be to tap for a helicoil of this size? Maybe it would be worth sending to the USA to get the tap and helicoil.
I'm going to visit the machine shop this afternoon anyway to get an estimate and see just what they're planning to do.
Thanks for any help you can provide!
Throw that nut away and get a new nut. It can't possibly be cost effective to Helicoil a nut. Which side? There is a left and right. Someone here must have a spare.
Lang's sells an axle thread repair kit, but the shipping on it to Spain would probably cost more than the kit. However, it might be worth emailing or calling them to try and work something out.
If you decide to skip the Lang's kit and go with helicoils, the helicoil kit size for the bottom threads is 1/2-20. The helicoil kit will come with the proper size tap. The proper drill size for the tap in the kit is 33/64 inch (0.516 inch).
No, he's asking about drilling out the threaded hole in the axle, which is ruined, and inserting a nut in the hole to replace the threaded part. I'd be inclined to fill the hole, redrill, and tap. But the nut idea should be OK.
Mark types and attaches faster than I type.
Earlier post on axle thread repairs;
Best repair would be to weld up the oversize hole, many times the hole is also oval shaped due to loose kingpin (spindle shaft), and then tap with correct 1/2" x 20 SAE threads.
and have the shop check for straightness of the axle too.
Early axle for the one-piece spindle body.
I'm not sure exactly what the problem is. Are you referring to the threads in the front axle where the king pin goes or are you talking about the threads on the nut that goes on the end of the spindle? If it is the threads on the spindle nut you can order the correct nut and assuming the threads on the spindle are still good you are done. Just remember that one side is left hand thread and the other is right hand thread. If it is the axle where the threads are then you have a couple of options one of which is to order the helicoil. Another would be to weld up the hole and then drill and tap it.
Eric, I agree with Steve, weld up the hole and re-drill and tap a 1/2-#20 thread. While you are at it check the upper hole for wallowing and repair it if necessary.
Why The others are thinking spindles is not clear to me. Your description of the problem is very straight forward. Your machinist should be able to knock this out in a couple of hours. Good luck!
Thanks very much for the input guys.
Just to confirm, the problem is the threaded area in the axle that the spindle bolt threads into. The upper holes seem to be free of any play or slop.
Mark, I hadn't ever seen the Lang's repair kit. That's a pretty slick fix and sounds like the way to go for a non-welder like me. It looks like I'll have to get hold of the proper tap as well.
I left the axle at the machine shop a little while ago (before I saw your responses). They should call in the morning to give me an idea of how they intend on going about it. My "Mr. Thrifty" nose smells something in the range of 100 to 150 dollars probably. I'll let you know!
Eric: The Lang's kit is the inserts of a STEVENS Front Axle repair kit. You need the tooling to install. Search the forum for Stevens front axle tool. Dan
Hi Dan, Steve at Lang's told me to contact you.
I think the remains of the bored out threads measures almost .60". Would the Stevens insert work there? Thanks.
Eric: Pm me and we can talk. Dan
This is another time when Keyserts may be the best answer. These are available in different outside diameters for the same size inside. So a badly flogged hole can be accommodated with a thicker keysert.
I have no idea of their availability in Spain. The US forum members also call a similar product a threadsert.
Hope this helps.
Allan from down under.
My price guesstimator wasn't far off, 128 Dollars, just about in the middle.
They put in a hand made Keysert. Metric threaded into the axle and the proper 1/2 - 20 inside thread for the bolt. The thread goes from top to bottom but allows the new bolt head to seat at the top of the axle.
Next bad front axle I find will be repaired with a Steven's system.