Its like the other poster stated, once a self tapper is removed once, it never goes back in as tight or holds as well as the first time.
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Little help around trailer screws
- Thread starter klingsdesigns
- Start date
Its like the other poster stated, once a self tapper is removed once, it never goes back in as tight or holds as well as the first time.
OldPaint
New Member
now who told you that??? using that which you say.....removing a spark plug........then it never goes back in tight????)))))))))))))
TORQUE............UNDERSTAND IT................. then you will see.......
http://www.engineersedge.com/calculators/torque_calc.htm
TORQUE............UNDERSTAND IT................. then you will see.......
http://www.engineersedge.com/calculators/torque_calc.htm
SightLine
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He is not talking about machine thread screws and bolts. Its a problem with DRILL point screws (not the same thing as self tapping screws but most do not really know this and use the terms interchangeably). Ever notice that when you remove a drill point screw that often times is gets stuck at the tip? When you remove and re-install a drill point screw you are then re-drilling the hole a little bit more after you also open the hole a little more when removing it. A drill point screw, if removed should be replaced with a standard screw. Very often they are replaced with a size larger to assure that the new screw holds as well as the original drill point screw. Ever drill a hole and wobble just a tiny bit and the hole ends up just a hair too big? A very common example is when drilling holes for tapcon screws. Very very easy to wobble just a tiny bit and then the hole is too big for the screw to get a good bite. It takes very very little to make the hole that the drill point screw was removed from weaker and no longer able to hold as well, particularly if the hole was in soft aluminum or low grade steel.
bob
It's better to have two hands than one glove.
Not quite there Mr. Engineer..
The operative words here are 'self tapping' be it a drill point or any other point. Moreover the 'drill point' is a taste smaller the the body diameter of the screw. Once tapped, the hole is tapped. A screw, one of the six simple machines by the way, will want to enter a tapped hole properly if given half a chance. The coarser the threads the easier it is. It's far easier for it to follow the tapped threads, crude as they might be, than it is to re-tap the hole. Moreover the 'drill point' is a taste smaller the the body diameter of the screw. This allows even thumb-fingered mouth-breathing oafs to use and reuse them a reasonable number of times without making the hole perceptibly larger.
Pat Whatley
New Member
OldPaint
New Member
BINGO...........i erected many METAL BUILDING, now these are STEEL SHEETS, STEEL FRAME & AND STEEL SCREWS....... so no dissimilar metals involved. TORQUE on these(they last 20-30 years) and can be removed and replaced........USING THE SAME SCREW HOLES........SAME SCREW numerous times without any ENLARGEMENT OF HOLES!!!! so who ever is telling you this.......dont know SCREWS))))
Attachments
visual800
Active Member
the only way taking screws out and putting them back in messes up the original hole is that whoever put them back in went too fast on the drill. for years we have taken these things out and I always replace screws slowly and only remove a small ammount at a time while doing trailer
OldPaint
New Member
i forgot to say this: ONCE THE DRILL/SELF TAPPER MAKES THE HOLE........the THREADS OF THE SCREW WILL .......make the hole a little bigger.......yes.........and if you take the screw out.......the drill tip going back in has no metal to cut as the hole is bigger(just a tad) then the drill tip. and as others have said...........is people not knowing when to stop TIGHTENING the screw........thus it STRIPS THE HOLE OUT)))
SightLine
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Old - its actually some occasional comic relief on here to post in a thread you are commenting in. It take so very little to get your knickers in a twist and you shouting things your really know nothing about. Regardless mister fastener engineer..... I'm not going to argue with you further. I did have a term incorrect though so I do digress on that point. There are self driving and self tapping screws. Self tapping are the drill point type. Do feel free to get in touch with a quality fastener manufacturer like Melfast to learn more though. You think those companies making the cheap flimsy utility trailers are using top quality spec fasteners or cheap "sort of" close to spec low grade ones in bulk from China for the cheapest price they can get? I've seen the failures on utility trailers first hand where you can push on a corner and the entire trailer deflects in a trapezoidal manner to the point that its truly unsafe to use on the road. I see and work with city buses that have over 2 million miles on them, when they replace or remove a panel on one that was originally installed with a self tapping fastener, the fastener is never replaced. One of several options, a larger fastener is used, a nut and bolt is used, a rivet is used, or a rivnut is installed and bolt used. There is good reason why in many critical areas its strictly documented to never use the same fastener a second time like real steel buildings (not little thin backyard buildings), engine components, aircraft components, etc. Its because almost all fasteners slightly stretch, distort, and deform when installed to their proper torque. That's how they work and its by design. The slight stretch of the fastener is what keeps it tight. Of course more often than not people also over tighten fasteners as well which also adds to the problems.... Anyways - I made my comments. I'm done, yall' have a great 4th of July weekend!
OldPaint
New Member
#1..................when i type in CAPS........i dont consider it YELLING. THATS YOUR INTERPRETATION......... not mine.
as CAP LETTERS where, have been prior to your thinking of their use........they are used most of the time for EMPHASIS........... or as i say EM -FA-SAS.........yea i dont spell good either.....BUT(emphasis)
I KNOW FASTENERS(again emphasis).
#1. i am a trained draftsman
#.2. set blueprints and bolt/screw specifications for METAL BUILDING, that i also helped erect.
#3. been a mechanic, since i was 7-8 years old, new how to tell a grade 5 from a grade 8 and where each was used and why before i went to high school. i took mechanical drawing 8th grade we had to, and i took it the next 4 years.......as an elective......cause i wanted to )))) then went to drafting school for 2 more years. so the engineering end ........I AM QUALIFIED........ to know what i say.
#4. since i was so good mechanically i also worked as a parts guy at NAPA AUTO PARTS from 1970-1985)was the paint and body guy, and also was the outside salesman for many of the stores i worked at. ALSO attended a school for salesman for products i sold........for instance PAINT, MARTIN-SENOUR. and the fastener company ROCKFORD......as we sold to garages and body shops......ALL THE FASTENERS......... they use))))))))))))))))))))
i think iam DUN))))) now to go watch JOE DIRT 2)))
grafixemporium
New Member
I would recommend strongly against removing every screw in a trailer. Those aluminum panels will likely never go back together the same and the client may end up with rattles and loose panels that were not there before. Wrap over them with 180cv3 and prime around and on every single screw.
OldPaint
New Member
WORK SMARTER.......NOT HARDER.......has always been my guide to working with trailers/rivits/corrugated siding on anything.........there are EASY things you can do or HARD WORK you can do.
as for removing ALL THE SCREWS AT ONE TIME...... NO DONT DO THAT...... it will cause problems later.
take out as many as you need to get a 3-4 ft section down.......THEN PUT THE SCREWS BACK IN, THEN REMOVE the ones where your going to put the rest of the vinyl. simple))))))))))
WHEN YOU STRIP A SCREW.........replace it with the next size up))))(#6, #8, #10 or #12) simple)))) and most of these trailers the inside is accessible if need be you can replace the scew with a nut n bolt))) but a lot of people have no mechanical aptitude...........i love my wife........and she is one of those.......i have to set the drill/screw drill clutch at less then tight......... when she uses it cause she cant seem to release the trigger when the screw is as tight as it needs to be......and she can strip the heads......for some reason she cant hold the drill/screw drill perfectly straight....she thinks it dont matter)))) this is hers...12V will twist your wrist)))
as for removing ALL THE SCREWS AT ONE TIME...... NO DONT DO THAT...... it will cause problems later.
take out as many as you need to get a 3-4 ft section down.......THEN PUT THE SCREWS BACK IN, THEN REMOVE the ones where your going to put the rest of the vinyl. simple))))))))))
WHEN YOU STRIP A SCREW.........replace it with the next size up))))(#6, #8, #10 or #12) simple)))) and most of these trailers the inside is accessible if need be you can replace the scew with a nut n bolt))) but a lot of people have no mechanical aptitude...........i love my wife........and she is one of those.......i have to set the drill/screw drill clutch at less then tight......... when she uses it cause she cant seem to release the trigger when the screw is as tight as it needs to be......and she can strip the heads......for some reason she cant hold the drill/screw drill perfectly straight....she thinks it dont matter)))) this is hers...12V will twist your wrist)))
