Taps and dies specific to automotive applications

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Batmanacw

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I recently had a project that required making a puller for a pickup truck rear axle bearing. The bearing housing had 12x1.25mm threaded studs to pull on. This was my solution that worked very well but thats not what the thread is about. I had spiral point taps so i was able to muttle through, but i immediately ordered a spiral flute tap for future projects. I needed a die to clean up the rusty threads on the studs but i didn't have that either so i ordered an Interstate brand die.

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The real question is about what thread diameters and pitches do you see on automobiles the most.

I have all the standard sizes and usually coarse and fine threads in each metric size.

I had taps in 12x1.25, 12x1.5, and 12x1.75. I'm better equipped now. I'd like to know what other less common sizes i can stock up on for my unpredictable future. Lol.

Don't tell me to wait to order it. I want to expand my selection ahead of time.
 
Ever since the botched metric conversion by the domestic automobile industry in the early 1980's, you've constantly got the risk of not being able to match a found thread. There's some seriously oddball stuff to be found in brake systems and bleeders, for instance. Decimal sizes with decimal pitches, like 4.7mm x 1.7 pitch on brake banjo fittings, seriously goofy stuff. For chassis and engine, you should have the 99% solution already in your threading kit. Unless you want to make tie rods/drag links, those get goofy too, but I'd recommend buying as you go for steering gear like that. Just too many variables. I retrofit my Suzuki Samurai to run Toyota FJ45 threaded rod ends, the right and left hand version of that backwards-kooky tap cost quite a bit- I'd make my own taps for that stuff if I did the job now. So yeah, steering and brakes will throw you the hardest-hooking curve balls in your endeavor.
 
pontiac428 said:
Ever since the botched metric conversion by the domestic automobile industry in the early 1980's, you've constantly got the risk of not being able to match a found thread. There's some seriously oddball stuff to be found in brake systems and bleeders, for instance. Decimal sizes with decimal pitches, like 4.7mm x 1.7 pitch on brake banjo fittings, seriously goofy stuff. For chassis and engine, you should have the 99% solution already in your threading kit. Unless you want to make tie rods/drag links, those get goofy too, but I'd recommend buying as you go for steering gear like that. Just too many variables. I retrofit my Suzuki Samurai to run Toyota FJ45 threaded rod ends, the right and left hand version of that backwards-kooky tap cost quite a bit- I'd make my own taps for that stuff if I did the job now. So yeah, steering and brakes will throw you the hardest-hooking curve balls in your endeavor.
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Ive got an insane number of taps bought surplus that are not standard thread combinations. They may someday come in handy. Im just trying to cover my bases the best I can while kerping the cost manageable.

I do have a great selection of metric taps. The lack of a spiral tap made the project much more laborious. If i can get a good selection now for $10-$15 each for quality taps I'll spend the money now.
 
I think having .25-pitch steps is important with metric, where anything goes. Have you tried shopping big lots of spiral taps on ebay? Since so many of those tools are retired from production, and manufacturing uses spiral taps exclusively, you should be able to grab a bunch for small coin. I can't say any of my spiral taps were bought new, all were loot hauls from auction lots or freebies of one type or another.
 
Batmanacw said:
Ive got an insane number of taps bought surplus that are not standard thread combinations. They may someday come in handy. Im just trying to cover my bases the best I can while kerping the cost manageable.

I do have a great selection of metric taps. The lack of a spiral tap made the project much more laborious. If i can get a good selection now for $10-$15 each for quality taps I'll spend the money now.
Click to expand...
Do you get the Travers sales catalogs? They frequently have sales on different items, but you need to use the product code in the catalog to get the sales price, if you search by the item, it doesn’t always show the better price. This month, adding a J at the end of the item number gives you the sales price.
 
pontiac428 said:
I think having .25-pitch steps is important with metric, where anything goes. Have you tried shopping big lots of spiral taps on ebay? Since so many of those tools are retired from production, and manufacturing uses spiral taps exclusively, you should be able to grab a bunch for small coin. I can't say any of my spiral taps were bought new, all were loot hauls from auction lots or freebies of one type or another.
Click to expand...

I appreciate where you are coming from with buying lots but I'm alergic to breaking taps. Im more than a bit leery of well used taps. You just can't tell how much life is left in them. Especially in a poor quality picture.

Ive been buying new taps cheap on Ebay. I checked and I have spiral, spiral flute, and hand plug taps in 6 to 12mm save a hand tap in 12 x 1.25. I'm not sure what bigger sizes I'll need.

Im sorely lacking in dies.
 
No doubt, broken taps are the worst. I have a Walton broken tap removal set that saves my skin most of the time. They won't help a helical flute tap, though. I've had to drill a NPT tap out of a recess with a diamond bit before on a phenomenally expensive part. I never want to repeat that experience.

On metric dies, at least with Asian auto imports, I rarely see the need to work male threads. Just the usual thread restoration here and there, but that's different from cutting threads.
 
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To join in the rest, there is no easy answer. The Metric sizes on my sons' 4 runner are different from the sizes on my Dodge. Say 8mm X 1.25 vs 1.5 or 1.0. If you can pull some non critical bolts, you can get an idea of what you will encounter. I have good luck with parts catalogs from OEM. When I plan to do something, I look up the attaching bolts and see what size and thread they are. I make sure I have a real tap and die. Also, about 20 miles away is a real nut and bolt store, When I pass by I get a couple of that thread in several sizes. Enough to save an emergency run in the middle of a job. Getting ready to change the Cat Converter, so I will make sure I have new bolts and nuts on hand

Also. I have Word Docs on all vehicles, tools , equipment. It shows purchase, mileage, date, repairs, oil changes and part numbers. I can tell you every thermostat change, the make and part number used and the bolt size since day purchased. Saves a lot of time when 3 years later you have to choose what brake size you have after you have figured it out 3 years earlier.
 
I did front bearings for my Bro-in-law and on a completely different vehicle the m12 x 1.25 thread bolts were the primary fasteners. They were 17mm head. The 10mm bolt holding the wheel speed sensor was 6x1. I failed to check the slide bolts on the brakes but I think they were m8x1.
 
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