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Tap (and die) set

tyconnell

Well Known Member
I don't own a set yet. I'm currently finishing up the left elevator on my -9A emp kit. So that the hardware would not get lost, I screwed in the trim cable cover plate, and two of the SS screw heads stripped during the process.

From what I gathered reading here, this is fairly common. The screwdriver I used was not so great. Ordered a Wiha PH #2 to see if those are worth it. Also, I will use Valve Grinding Compound on the threads which is supposed to help.

On to the question - the first thing I thought of when I stripped the heads was "these need to be tapped." I did some reading here on VAF, and there is a never-ending-debate regarding tapping plate nut vs. not.

I know what a tap and die set is used for in general, and there are a couple of posts by fellow VAFers who swear by having a set. But if you're not tapping narfed plate nuts, what tasks during the build are accomplished using a set?
 
I have the powder/wax BoeLube and sprinkle that into the screw tray or bag prior to installing. It cuts down significantly on friction and helps avoid the stripped heads.

Nut plates are designed with friction as a locking device (e.g. lock nut). Running a tap through essentially ruins that locking function.

I have owned a tap and die set for 30 years but didn't use it when building except where the plans specified it for screw installation in the aft longerons for empenage fairings.
 
Tap and Die

Ty, you use the valve grinding compound on the end of the Phillips bit to decrease slippage of the bit, not on the threads. You probably meant this, but it came through, to me, as you were going to put it on the screw threads...

I have used various different lubricants on nut plates. Currently I am using Gulf brand canning wax. This does help get the screws in/out, but sometimes it just makes sense to "ease" the threads a very little bit with a tap. Experiment with a nut plate to figure out how to ease the force required to insert screw without loss of the locking feature.
 
...and two of the SS screw heads stripped during the process.

Your solution for these screws is not a tap and die, but rather a screw extracter set from your local hardware store. You first drill a small pilot hole in the head of the screw and then screw in the extractor in a counterclockwise direction. Should pull the mangled screw right out.

Once a platenut has been used a couple times, they tend to loosen up significantly. A little Boelube on the screws helps as well in the first installation. I only tapped platenuts where Van's specifically instructed and have not had any trouble with screws after the first or second time.

Good luck.
 
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I don't own a set yet.

--- snip ---

I know what a tap and die set is used for in general, and there are a couple of posts by fellow VAFers who swear by having a set. But if you're not tapping narfed plate nuts, what tasks during the build are accomplished using a set?

A tap and die set is not necessary to build an RV kit aircraft.

The tap and die sets that I own are 40-years old. They are nice to have when one finds a damaged thread on a bolt or nut and a NEW bolt, nut, or plate nut is not available. It can be used when needed to repair a part that should have been replaced.

As others have said, one should not use a tap on plate nuts but sometimes there may be one plate nut that needs it threads cleaned out removing its locking feature. Not something that you will do to every plate nut but something you may do to add a fastener on a plate nut that needs replaced but you do not have the time or access.

Any cheap set is nice to have in the tool box. Better quality individual taps can be purchased if you need them.
 
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Go to your local hardware or plumbing supply store and get a bees wax toilet sealing ring. Must be bees wax, not some modern synthetic substitute.

Use a dab of bees wax on the threads of your SS screws and/or the nutplate threads. This will allow easy insertion of the screw yet still maintain the locking ability of the nutplate.

One toilet ring should last you a lifetime and be under $10.00.

Bees wax is also good for taping aluminum, and other jobs in the shop.

As for the tap set-------Like Gary said you should not need one to build an RV. Also, do not run the tap through the nutplate-----you are destroying the locking function of the nut plate if you do. They are meant to grab and hold on to the screw/bolt in normal use.

One last thing-------the first time you insert a screw into a new nutplate, not only use a dab of bees wax, but drive it by hand------stay away from the power driver.
 
Ty, you use the valve grinding compound on the end of the Phillips bit to decrease slippage of the bit, not on the threads. You probably meant this, but it came through, to me, as you were going to put it on the screw threads...

Actually, I did mean on the threads, and not on the Phillips bit, so I had that all wrong!

Your solution for these screws is not a tap and die, but rather a screw extractor set from your local hardware store. You first drill a small pilot hole in the head of the screw and then screw in the extractor in a counterclockwise direction. Should pull the mangled screw right out.

Sorry, I wasn't more clear in my post. The question regarding tap and die set wasn't for removing the screws - it was for "what else are they used for" since I had inferred, from other posts, that tapping plate nuts was "bad". I actually own a set of screw extractors having broken off bolts in metal before.

I have owned a tap and die set for 30 years but didn't use it when building except where the plans specified it...

A tap and die set is not necessary to build an RV kit aircraft.

Darn, I'm a bit of a tool junkie. Was hoping someone was going to give me an excuse here. :D
 
I get the worry that re-tapping a plate nut may defeat its purpose. But be aware that it's not uncommon to have the heads of A/N #6 steel screws twist off while *installing* them in some plate nuts. I'd call that a bit more tension than actually needed; yes? And since it's spring steel that flexes back into a circle when a tap is run through it, it would take many re-tapping operations to truly defeat its function.

On owning a set of taps: I've got a few decent quality taps in the common sizes, and el-cheapo full sets from Harbor Freight in both standard and metric. The HF stuff won't last long tapping steel, but I've used them for aluminum a lot (non-typical stuff, to be sure). I've also got a set of HF pipe taps & dies, that have lasted through plumbing gas lines through an entire 3000 sq ft house and are still going strong.

For a completely stock build, you probably don't really need a set. But I've found lots of uses for mine. Consider locations like the anchor points for the shock struts for a tipup canopy. A tapped plate eliminates the need to get a wrench into the top longeron assy to hold the nuts.

FWIW,

Charlie
 
Darn, I'm a bit of a tool junkie. Was hoping someone was going to give me an excuse here. :D

Ok, permission granted ;)

Seriously, there are a number of nutplate locations where frictional locking power just isn't necessary. For example, I don't hesitate to tap the four nutplates holding an EFIS in the panel. Same for the seat pan/mid floorboard/footwell panels in the -8. Even if those screws came out (they don't) it wouldn't hurt anything. Locking just makes inspection a pain in the butt.

Lockers are for locations that would create a hazard to flight.
 
Darn, I'm a bit of a tool junkie. Was hoping someone was going to give me an excuse here. :D
< If Dan is going to get serious >

Hmm, me too. But, "He who dies with ... wins." I don't look for excuses, for I spend a lot of time seeking forgiveness :).

I promise, you WILL find an incredible use for that "tap and die set" (insert whatever $$,$$$ tool) to fix the tiniest thing around the house in an instant. Then it is up to you to channel you're inner Steve Jobs, "It's Magical isn't it!?".

Just be careful what you ask for. A wise family member said the other day, "You can only play with so many fun tools at a time. Then you have to hire people to operate them. That turns into work real quick and takes all the fun out of it."

Oh, I'm sorry, you were just talking about a tap and die set. FORGEDABOUDIT!.
 
If you are going to buy a tap and die set, and use it for other purposes than tapping aluminum for an RV, buy a good set. HSS (high speed steel), USA, etc....
The first time you snap off a cheap Chinese made Harbor Freight or other brand in a part, whatever you saved just flew out the window.
If you use a tap often, you will side load one and accidently break it off. The better brands, like Irwin, are just tougher and less likely to snap, especially the small sizes.
ACE Hardware sells individual Irwin(Hanson) taps and dies if you don’t need/want to buy a full set.
The small general tap and die set from Irwin will cost you about $125 in SAE or Metric.
Also, you can occasionaly find used manual tapping machines on CL. These are good for repetitive hole tapping on flat stock. I picked up a quality US Made one for $50, a $250 plus machine.
 
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Only times (that I remember) using a die was on the SS baffle tie rods I used under the cylinders instead of wire. Even with a HSS quality die had to take it real easy on the SS with lots of back & forth. Also used a #6 tap on a hole into the gear tower lower weldment for the forward attach screws on the upper gear leg intersection fairings. It wasn?t practical to use a nut plate here (more holes and a pain to buck) and another nut in the gear tower would have made me even more nuts.
 
For a completely stock build, you probably don't really need a set.

I would argue completely the opposite. On my stock RV-7 slider I have so far used 6-32, 8-32, 10-32 and 1/4-28 taps, all as specified on the plans. However if you deviate from stock there are ways around most of those.

To the OP, be aware however that I initially bought a cheap HF set but found it included none of the sizes needed! When I checked at sears I also couldn't find a set that had all the sizes, so you'll need to check that carefully.

And if you need an excuse to buy tools don't forget that each tap needs a number size drill bit for the hole, so you might as well go ahead and get a full set of 1-60 number size bits, another buy I have never regretted. Almost every month these days I also wish I'd got the letter size set.
 
Plans call for several taps and at least one die.

In my slow build -10, I can remember being required to tap threads in the T section extrusion for the tie-down points in both wings and tail, as well as #6 threads in the longerons near the tail to secure the empennage fairing. The FWF section called for cutting threads in the baffle tie rods, although I found those next to impossible to thread properly and ended up buying pre-threaded rod for that part.
 
Since I have a PDF preview plans, I searched for "tap" in it and ran across the list of ones you will need in the tools section and a number of spots where they get used. I'm surprised by the number of times I don't think to do that first.

That list is:
1 x 1/4-28 Tap
1 x 5/16-24 Tap
1 x 3/8-16 Tap
1 x 3/8-24 Tap
1 x 4-40 Tap
2 x 6-32 Tap
1 x 8-32 Tap
1 x 10-24 Tap

I'm not sure why you would need 2 x 6-32 Taps. Also, I didn't see all of these called out in the manual - some places say "tap this, see drawing X" kinda thing. Maybe they are in the drawings.

Anyhow, once again, I appreciate all the feedback here. And the "permission". :D
 
I would argue completely the opposite. On my stock RV-7 slider I have so far used 6-32, 8-32, 10-32 and 1/4-28 taps, all as specified on the plans. However if you deviate from stock there are ways around most of those.

To the OP, be aware however that I initially bought a cheap HF set but found it included none of the sizes needed! When I checked at sears I also couldn't find a set that had all the sizes, so you'll need to check that carefully.

And if you need an excuse to buy tools don't forget that each tap needs a number size drill bit for the hole, so you might as well go ahead and get a full set of 1-60 number size bits, another buy I have never regretted. Almost every month these days I also wish I'd got the letter size set.

Boy, Ed; how far do you need to go, to make yourself feel significant? ;-)

I suppose that a list of 4 taps (and no dies) could be considered a 'set', if you're using the strict mathematical definition. And I suppose that if you extract one sentence, out of context, from a multi-paragraph post, you can make yourself look like a higher authority.

To help you out, here's a HF set that is pretty cheap, and includes the sizes you list. Most vendors include a list of what's included, if you read before you purchase.
https://www.harborfreight.com/hand-tools/tap-die/40-pc-carbon-steel-sae-tap-and-die-set-63016.html

Charlie
 
Ace

About $5 each and you have a quality tool that will last and shouldn’t break.

Less. I get a senior discount!
Actually, living in a tiny hamlet (population 6,000), my only aviation supply store is Ace. I go in so often, they take really good care of me.
 
Boy, Ed; how far do you need to go, to make yourself feel significant? ;-)

I suppose that a list of 4 taps (and no dies) could be considered a 'set', if you're using the strict mathematical definition. And I suppose that if you extract one sentence, out of context, from a multi-paragraph post, you can make yourself look like a higher authority.

To help you out, here's a HF set that is pretty cheap, and includes the sizes you list. Most vendors include a list of what's included, if you read before you purchase.
https://www.harborfreight.com/hand-tools/tap-die/40-pc-carbon-steel-sae-tap-and-die-set-63016.html

Charlie

My apologies if you took offence. I was certainly not trying to "make myself feel significant" and nor do I think myself a "higher authority".

But during the course of my build, like many here, I have gained knowledge and experience. In this case that knowledge differed from what you posted. I sought to provide the OP, and the many who may read this thread in years to come, with what I consider to be accurate information.

If everyone who posts their knowledge and experience here were put off by the thought of seeming condescending, then this site would wither and die.
 
Ordered a Wiha PH #2 to see if those are worth it.

I use a nut driver handle with driver bits. ACR is enhanced engagement. Get a good brand and stick with them WERA is a good one as is Wiha. They won't work in tight spots, but I use a Dewalt driver with adjustable torque (release) and absolutely love it. Since using only driver bits far, far, fewer slips have occurred., and cheaper too. I have no hesitation about trashing the bit fror a new one.

SS is softer, so expect higher friction in the threads and more head slips. Use only for final assembly.

I always use the standard steel screws and lube to pre condition the nut-plates. Kind of a pain, but gotta be done. Then just throw away the conditioning screws.


Like Jon mentioned, Hanson makes a good T&D set, get one, you won't be disappointed. Should get one for less than $100.
 
So, stopped by the Ace store today, which is moving due to strip mall construction, and picked up Irwin Hanson 4-40, 6-32, 8-32, and 10-24 Taps plus a t-handle for ~$20. Good sale they have going on due to the move, saved about 40% off retail if my math is right.

Another question - there are "thread types" - NC, NF, et. al. I'm assuming I'll need the NC types? I passed on a larger size (the 1/4-28 or 5/16-24, I can't remember which) because it was an "NF" thread type.

I've read the Irwin ~40'ish page pdf on all there taps, and from what I understand the NF is some kind of "fine" thread, vs. the "coarse" thread.

p.s. - got the Wiha, and it's a bit longer than I had anticipated, but WOW! I'm totally ruined on screwdrivers now.
 
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So, stopped by the Ace store today, which is moving due to strip mall construction, and picked up Irwin Hanson 4-40, 6-32, 8-32, and 10-24 Taps plus a t-handle for ~$20. Good sale they have going on due to the move, saved about 40% off retail if my math is right.

Another question - there are "thread types" - NC, NF, et. al. I'm assuming I'll need the NC types? I passed on a larger size (the 1/4-28 or 5/16-24, I can't remember which) because it was an "NF" thread type.

I've read the Irwin ~40'ish page pdf on all there taps, and from what I understand the NF is some kind of "fine" thread, vs. the "coarse" thread.

p.s. - got the Wiha, and it's a bit longer than I had anticipated, but WOW! I'm totally ruined on screwdrivers now.

Your smaller screws and bolts, #8 and down will typically be UNC.
Your larger screws and bolts, #10, AN3, AN4 etc... will typically be UNF.
There are a few cases, especially with engine stuff like studs, that you may have 1/4-20 UNC, but they are limited.
I don't have my manual handy, so others can correct me as required....
 
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...by the way, ACE continues to improve their product offering. They still offer cheaper foreign tools, but have continued to bring in better USA made stuff too, at reasonable prices. ACE is also a retail cooperative with local store owners and stockholders. Harbor Freight is owned by an American Billionaire who made his money importing cheap machines and tools, primarily from China. I am sure China is very happy with him. I doubt we can calculate how many US manufacturers and workers companies like HF displaced. I wont shop there.

I'm SUPER bummed about them moving - it was a very convenient store location wise, and they seemed to always have what Home Depot didn't.

My harbor freight purchases have been limited to a few odd length "scrap bin" air hoses that were super cheap and in the 6'-8' length that I needed. I've purchased more than a few "cheap" tools, and can't remember one I've been happy with. Quality tools are just more fun to work with, and fun is what this should be about, right?
 
I'm SUPER bummed about them moving - it was a very convenient store location wise, and they seemed to always have what Home Depot didn't.

My harbor freight purchases have been limited to a few odd length "scrap bin" air hoses that were super cheap and in the 6'-8' length that I needed. I've purchased more than a few "cheap" tools, and can't remember one I've been happy with. Quality tools are just more fun to work with, and fun is what this should be about, right?

Ya, sorry, I deleted my comments about HF but didn't do it quickly enough. It borders on politics which is a VAF no no.

Anyway, you are off to a good start with good questions.
 
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