Tap & Die set

Measuring threads update

Hi all

Got my thread guages tonight and measured all the UNF bolts I have for the suspension. They measure 20 using the V-US-AMER-NAT guage which marrys up with this rethreading bit from snap on, does this all look right so far?
TRT4320A, Tap, Rethreading, NF, 7/16"-20




OK so final question. Ron earlier stated that the above snap on bits were thread chasers not taps, is this correct? However I spotted this tool on the same snap on website that claims to be a thread chaser
TR25B, Set, Thread Chaser, Internal, U.S.

So which do I need to buy? I don't need to create any new threads just run something through the new bolts to clean them before fitting the suspension.

Trev
 

Alan Watkins

Lifetime Supporter
Re: Measuring threads update

...does this all look right so far?

....
OK so final question. Ron earlier stated that the above snap on bits were thread chasers not taps, is this correct? However I spotted this tool on the same snap on website that claims to be a thread chaser
TR25B, Set, Thread Chaser, Internal, U.S.

So which do I need to buy?
...

Yes, you're using the gauge correctly....

Re the TR25B... that's a different style of internal thread chaser I've never seen before; I'm used to the kind, like the earlier Sears/Snapon set, that look like thread cutting taps but aren't. All I know is the earlier ones in this discussion work fine so you would be safe purchasing them. And I would observe that the TR25B set will be fussier to use since you will have to dismount/remount the "blade" for each different thread, rather than just select the right one and use it. And that for substantially more money you are getting only internal inch thread chasers, no external, and no metric.

(PS I just noticed something funny: the UK Snap-on site calls the "inch" threads "U.S.". I've always called the "inch" standard "English". So I guess we're each trying to blame it on the other.)
 
Re: Measuring threads update

...

Yes, you're using the gauge correctly....

Re the TR25B... that's a different style of internal thread chaser I've never seen before; I'm used to the kind, like the earlier Sears/Snapon set, that look like thread cutting taps but aren't. All I know is the earlier ones in this discussion work fine so you would be safe purchasing them. And I would observe that the TR25B set will be fussier to use since you will have to dismount/remount the "blade" for each different thread, rather than just select the right one and use it. And that for substantially more money you are getting only internal inch thread chasers, no external, and no metric.

Awesome, thanks Alan it's always worth triple checking. Will get a few of these ordered now

Trev
 

Alan Watkins

Lifetime Supporter
Re: Measuring threads update

However I spotted this tool on the same snap on website that claims to be a thread chaser
TR25B, Set, Thread Chaser, Internal, U.S.
Well this is interesting, from a tool-geek and terminology point of view: Snap-on classisfies the "tap-like" tool as a thread restorer, and the TR25B comb-like tools as thread chasers. So I guess that illustrates that there are two terms at work here: chasing, which I think means "following but not modifying" otherwise known as "cleaning", vs. "restoring" which I think means "reforming where necessary (but also cleaning)." That's an assumption I'm making given they carefully separate the two categories, I assume knowledgeably and on-purpose, and my guess that the "comb like" tool does not cut or re-roll the threads. But I don't know that that's true.

IAE, I still recommend the "restorer" over the "chaser" based on cost and the simple fact that I know the restorer does what's needed based on personal experience.

But I'd be interested to know if any other tool geeks are familiar with the "comb-like" tool and what its principle of operation is.
 

Alan Watkins

Lifetime Supporter
Right after I wrote that I tapped a 1/2" NPT hole completely crooked. I guess the skill comes and goes....

And actually, to take this seriously for a moment: what I should have done is use some kind of tapping guide; I would have but none of my usual tricks would work. For example, chucking the tap into a drill press and using it (hand rotated) to get the tap started because the 1/2 NPT tap is too big for my 1/2" drill press. Sometimes, you can do the same kind of trick with a die: lay the die upside down on the drill press table and chuck the workpiece in the drill press.

I then redid the work with the work piece in a vise and carefully leveled, and then with a small level on the tap, and starting the tap very slowly while watching the level. Same concept would work with a die.
 
Hi all

My tap & dies finally arrived from Snap On so I am going to clean all the threads on my suspension tomorrow.

I think I read somewhere that I need to use some kind of oil/lubricant on the taps/dies when using them. Can someone tell me what I should use, would something like WD40 be suitable?

Thanks

Trevor
 

Alan Watkins

Lifetime Supporter
Didn't get a set in the end just bought 2 taps and 2 dies that I need for the moment. The price was pretty good £12.50 for all 4.

Trev
The instructions that came with my Sears rethreading taps and dies just said to use oil (eg motor oil). It's not a critical application, and you're not cutting, so you don't need thread cutting fluid.
 
Alan's has a good point.... :)

Remember to make sure you degrease them properly afterwards otherwise it'll change your torque settings.
 
Hi Trev, My way of thinking is only get taps and anything else you need but get quality ones that will last, Not cheap chinky gear nothing with the year of the cat stamped on it.
'Save your money for that chrome cleaner '

If there's something you might need but can't justify the cost let me know I may have it and you can always borrow it.
 
Hi Trev, My way of thinking is only get taps and anything else you need but get quality ones that will last, Not cheap chinky gear nothing with the year of the cat stamped on it.
'Save your money for that chrome cleaner '

If there's something you might need but can't justify the cost let me know I may have it and you can always borrow it.
Cheers Keith appreciate the offer. I agree, going to try and only buy the tools I need rather than extra tools in sets etc that won't get used. Going to have a play with the tap & dies tomorrow night as I didn't get round to it today thanks to todays hangover

Trev
 
Hi all

Cleaned/restored a lot of the suspension parts tonight and all the bolts using the snap on tools. Used a drop of oil on the tap and dies as advised and the tools worked really well. All the parts are now ready to be fitted







Still have another batch to do but nearly ready for fitting. fastdruid, you mentioned degreasing everything after. Should I degrease all bolts and threads in the suspension housings or should any of these parts be slightly greased? The reason I ask is that the housings/threads at the end of the chrome suspension parts have a little grease in them.

Is this likely to be from where the threads were originally cut into the parts?

Thanks

Trev
 
Trev one thing that I don't use a lot but has really saved me loads of time and my butt are thread files. I bought my first one just a few years ago. Many times only the first one or two threads are munged up and the thread file can clean it up in nothing flat and save yourself a trip to the store which won't open until tomorrow (at least that's how it seems to work out for me).

On my car the is a special very long 1/2" threaded rod that the upper front control arm pivots on. If I had not had a thread file I would have had to have one made or ordered one from South Africa. Cheep and very useful but buy both SAE and Metric. The thread chaser won't fix that type of problem as it will almost never start straight.

If your really in a pinch I have cut a grade 8 nut in half placed it on the bolt on good threads and held it on with vice grips or in a vice with a little pressure and some oil then back it off the bolt. It may take more than one pass but the sharp edge of the nut will retrace the threads at least good enough to use as is or use the re-threader.

I must be strange (da) but I use both tapes and dies all the time but I was a tool and die maker in what seems another life. Just know you'll need both.

Good luck on your new ride you'll love working on and driving it is the best.
 
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Trev, depends on what your torque settings are, if they specify 'dry', 'oiled' etc.

Normally I'd grease the shank of the bolts then depending on the type of nut either use thread lock or a aero-lock/nylock. Then I coat the end of the bolt with copperslip as a typical failure after a few years is you undo the nut a few turns then it can't make it over the corrosion on the end and with a bit more force the bolt snaps....

That's with uncoated bolts though, not sure as what's best with chromed. I'd be kind of tempted to still do the same but put the little rubber bolt caps on to keep it neat and prevent the copperslip coming off.
 
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