[CliffordK (OP)]

Grrrr

I got a few little space heaters.  200W which is an excellent size for my needs.  Unfortunately, they have been failing.  [xx(]  So, I thought it was time for some repairs.

One of them, the cord split near the housing.  Not a big deal..   dig it out,splice it, reassemble...  Or is it?  Others have failed due to auto-off thermostats that failed, and one seems to have a rapidly failing fan.

It turns out the thing is put together with 5 screws.

Three of the screws are "normal".  Two of them are *^%$%$#$%%$!!!  triangular shaped.  And, it turns out that I don't have a single screwdriver with a triangular profile. 

They are buried about 2" deep in the device, so access is a pain, and even seeing them while I filed a screwdriver to shape would be problematic.  If only I can manage to jamb something in so I can dig one out.

The VW Injection Pump also uses a triangular bolt, which I made a custom socket to fit.  However, alas, that won't help me in this situation.

Anyway, I realize they may not want people messing around inside of the devices, or disabling safety equipment (the overheat thermostat that seems to fail so often).  But, it also seems as if preventing people from conducting simple repairs, it adds to our disposable society.

Perhaps I can go back to the store where they were purchased...  a building supply store that sells tools...  and demand that they sell me a screwdriver that fits the screws they are selling!!!

[Geezer]

I got a few little space heaters.  200W which is an excellent size for my needs.

What! Are you living in a cardboard box?


You need to nip down to your local Jar Jar Freight

http://www.harborfreight.com/32-piece-3-inch-long-reach-security-bit-set-95680.html

[CliffordK (OP)]

Ahh,
Got it.
I already have a "security screw" set with lots of 3/4" bits.  But, I needed longer ones.  The magnetic screwdriver wouldn't fit down the holes.  I was getting ready to weld a bolt to a 3-bladed Phillips screwdriver bit.  But, found a small flat blade that was able to pull them out (after filing down the handle to fit better).
 [ Invalid Attachment ]
I'm not sure if the 3-bladed Phillips screwdriver bit would work.  This looks deep, like the square bit screws, but is triangular instead.

Guess which screws will be deemed redundant, and won't go back in.

[Bored chemist]

A relatively simple exercise in geometry is to inscribe a hexagon in an equilateral triangle.

Granted, an allen key would only work if the screws were not very tight.

[Geezer]

A relatively simple exercise in geometry is to inscribe a hexagon in an equilateral triangle.

Granted, an allen key would only work if the screws were not very tight.

Geometrically yes, practically no. It would not take much torque for the key to ream a circular hole in the screw-head.
 
It might be better to take hex key and grind every other point off to make it triangular.

[CliffordK (OP)]

For the VW Injection Pump bolt.
I took a 12mm, 6 pt impact socket, and ground out every other face with a dremel, so it would fit the triangular bolt.  Then I discovered that it had too thick of a wall, so I thinned the outer wall slightly.  It worked great.

I should have thought about the Allen wrench for the internal triangular screw head.  If I can get one with a tight fit, it should work.  These are just wood screws in plastic after all.

Now that I have two screws out, I could also grind a custom driver, probably starting with round stock.  An old screwdriver?  Thrift Store Screwdriver?

Oh, in answer to Geezer's earlier question.  No, I'm not in a cardboard box...  but that does give me some ideas.  []  My house is probably too big... or just right, however you think about it.  [8D]  Anyway, I've chosen to heat near where I am, but not evenly heat the whole house.  The 200W space heaters give a very localized heat...  perhaps too localized  [V]

[SeanB]

I have taken a steel rod and ground it down to the correct profile, and then did some hardening ( not much on the steel, but enough to stop it stripping ) and used it. Then I replaced the screws with more available units, and sent the nasty hardened units to scrap. The fan probably just needs a drop of engine oil on the bushes, which probably is what killed the non resettable thermal fuses in the first place. You can buy those from appliance repair places, or in the USA try online, amazon has thermofuses.

[Donnah]

Gr.

It turns out the thing is put together with 5 screws.

Three of the screws are "normal".  Two of them are *^%$%$#$%%$!!!  triangular shaped.  And, it turns out that I don't have a single screwdriver with a triangular profile. 

Ha, ha, ha, that scenario is so familiar!  But somehow when it happens to someone else it is funny.  We have a garage plus a toolshed and a trailer full of tools and I am amazed at how often we have to go and buy another "specialized" tool.   

Why don't we standardize tools?