Allen Head Screw Major Problem

[scooter339]

I am trying to remove bottom of my P2 and there is one Allen head screw that has have been over torqued during assembly I think. The head isn't quite stripped yet but it's getting close. I have three different typed of drivers and I can't make it budge.

I had a similar problem the last time I took a case apart with one of the tiny Phillips head screws. Now I have one of each a Philips head and Allen head.

WHAT DO I DO? I'M EXASPERATED.

 

[Fink]

Are you sure it's that it's over-torqued and not otherwise stuck? You could try using some WD40, Liquid Wrench or PB Blaster to see if that helps give it the push it needs. Let it soak on there for 15 minutes or so and give it a go. Try and dab up as much of the stuff you use on the head of the screw as you can before going at it, of course.

If worst comes to worst, there's the old use a Dremel to notch a groove in it and then use a flathead screwdriver.

Fink

 

[scooter339]

Well, between those two welcome suggestions I got a way to go.

If it comes to a Dremel and that doesn't cut it, does that mean I have to drill it out? Worst case scenario, would that mean a machine shop?

 

[Fink]

Well, between those two welcome suggestions I got a way to go.

If it comes to a Dremel and that doesn't cut it, does that mean I have to drill it out? Worst case scenario, would that mean a machine shop?

I can't imagine you'd need a machine shop. It's not like we're talking about Grade 8 or Grade 10.9 hardware here. I imagine even a Dremel with a basic bit could get it out, but I'd only do that as a last resort.

Good luck!

Fink

 

[Paul K]

You can buy some liquid screw removal or put fast cure epoxy on tip of the allen ,let cure and slowly remove screw . Replace with same length and thread size screw from hobby store . These screws Made in China are poor quality and strip easily.

 

[EMCSQUAR]

Put the opposing allen screw in and relieve tension, then undo your problem one.

 

[scooter339]

I'm going to try everything. I'll let you know the outcome.

Thanks.

 

[fly-catchers]

An idea I find sometimes works with tight screws is to put the driver in the screw and lighty tap the screwdriver at the end a few times. This vibration has loosened the screw quite often. Worth a try!

bill

 

[Visioneer]

I had to remove eight screws to install prop guards. All went well until the last screw which would not budge despite my trying just about everything mentioned here. I wound up having to drill out the screw just enough to get a small screw extractor in it.

I used a Dremel tool, small bit, and magnifying glass; carefully drilling out a very little of the screw at a time until the extractor would bite. Cutting a slot with the Dremel for a flat blade screwdriver would not work because the screw head is recessed in the plastic ... getting deep enough into the screw would have meant putting a slot in the plastic as well (the diameter of the recess is no more than the size of the diameter of the head on the arbor that holds a cutting disk).

Two observations (info for factory [in my dreams] & for reassembly) ... 1) the screws I removed are dabbed with removable thread lock, 2) the screws go into the metal motor housing, so these screws are metal (screw) to metal (insert) that is compressing plastic. Accordingly, they do not have to be torqued so a gorilla cannot remove them.

 

[flyshasta]

I drilled and then used a screw extractor, too. Be careful not to get any shavings into motors.


Sent from my iPhone using Tapatalk

 

[scooter339]

I was able to extract the allen head screw from its anchor but not out of its hole.

First I moved one skid mount so I should get a straight ahead shot: http://screencast.com/t/qKRnZjYDC.

Next I sprayed the hole with PB and removed the excess from the head with 2 Q-Tips: http://screencast.com/t/TKYyyshSy

Rather than risk a wrench being even slightly damaged, I bought a new one with a longer handle. I had been using a 16" long allen head wrench and it is amazing the torque and flexibility it has. It was slightly worn though. Anyway, I was pretty happy when the screw released the case but the screw istself is still lodged in the hole.

HOWEVER -- THE PHILLIPS HEAD BY THE MOTOR IS AS STUCK AS IT EVERY WAS.

I tried the fast setting epoxy, maybe I bought the wrong on or the metal of the DJI driver was not the right type.

Check it out: http://screencast.com/t/syxiU71w7bo6.

What should I try first, the screw extractor? All we got in this town are the Home Depots ext, which don't carry anything less than 1/8" and we have two hobby stores.

I believe this problem is due to bad assembly practices and crappy hardware.

In any event, the next time I have to crack a case:

I'm using PB on every screw before I take a driver to it.

 

[Sledge]

I had the same problem.....I ended up having to use a Drexel with a flat disc and cutting a slot into the top of the screw head. Then use a flat head screwdriver.....It cut into the plastic a little bit, but didn't affect anything.

 

[Visioneer]

I tried epoxy as well (twice). Apparently the plated screw's surface is so slick that epoxy simply can't adhere well.

My initial attempt at drilling with my old Dremel (not variable speed) heated the screw and embedded it more securely in the plastic ... be careful not to go there - let the bit do its thing, very light pressure, don't push.

The extractor I used was from a set I'd had around for a while and I don't recall the brand, but it looks just like Vermont American 21822 (http://www.amazon.com/Vermont-American-21822-Extractor-through/dp/B000GTOOWA/ref=pd_cp_hi_1). The extractors in my set are marked No. 1 through No. 5, just like the VA set. The No. 1 I used is marked use a 5/64" drill. I measured the very tip of the extractor with a micrometer and it was right at 2.0mm (which is ~ 5/64").

 

[scooter339]

That was timely as I am going out the morning to get a Dremel. Very helpful regarding the heated screw. That's all I need at this point.

This looks like a far less expense method. I'll try this first before dropping a lot of money on a dremel.

Thanks.

 

[goldfishrock]

Yeah, you've got to be careful because the plastic posts they are mounted in are so brittle and break so easily. The screw quality is poor so I now have a couple of spare P2 screw sets to hand and replace any screw that looks like it's going to cause problems next time I try to remove it.

You can get replacement screw packs from these guys

http://www.buzzflyer.co.uk/DJI-Phantom-2-Spares/DJI-Phantom-2-Vision-Screw-Pack/p-212-2591/

 

[scooter339]

Thanks for the source. I guess shipping such a small package from the UK can't be too costly, maybe there are US sources.

So here's the outcome of attempting to extract the screw with the Vermont Tool 2 mm extractor:

http://screencast.com/t/dEdyqiDkxJl

In my view, the extractor was the best idea.

Guess I'll fill it up with silicone, unless anyone has a better suggestion.

Again, I reaffirm that I will never try opening the top or any DJI related assembly without PB Penetrating Catalyst. Sure, If I had a drill press with a 360 degree platform, this could have turned out better. I'll ask for one for Christmas.

 

[goldfishrock]

Some possible US Sources for that Replacement Screw Pack

http://www.uavdirect.com/DJI-Phantom-Replacement-Screw-Pack-p/djipsp16.htm

http://www.centuryheli.com/products/productdetail.htm?prtnm=DJIPHV21&pageid=1000

http://www.ebay.com/sch/i.html?_trk...sion+Replacement+Screw+Pac&_sacat=0&_from=R40

 

[scooter339]

Thanks GFR

 

[npalen]

I've had some success with tough allen head screws by grinding the end of the allen wrench and leaving the grinding burr. The burr helps tighten the wrench in the allen head.
Edit: Grinding the end also gets rid of any rounded portion on the hex. Just be sure to grind a little at a time and dip the end in water to prevent overheating and annealing the tip.

 

[neil64]

You could try putting the Phantom in the freezer for an hour or so to let the plastic shrink. That might let you get it out. If that doesn't work, try heat.

As for all these suggestions, If you can't get the screw out by turning it, using a rotary tool (like a Dremel) would be the best bet. You can get a cheap rotary tool (with bits) for like $10 (Example). If you use a Dremel, you could either drill the screw out, or try to cut a slot in the head of it (to turn with a screw driver). If you are drilling it out, be very careful because the screw will get hot and melt the plastic threads (It will happen, but don't push the screw further into the plastic). You will likely have to grab the screw and remove it after the plastic has softened. For cutting a slot into it, you will likely cut up the plastic around the screw hole, but it shouldn't be enough to ruin anything.