SME 3009 II Little screw Big problem

[sebalele]

Good evening ,
I'm from Italy , this my last thread from long time ,I read often and always found lot of help yours advices , many thanks .
After having play with 6/7 Lenco I was working on last PTP5 and I felt that my sme doesn't take the vertical height .
Maybe I have played a lot on this little screw .

Turnig too much screws on on SME has not to do often but , I always take care not to overtight ..
The screw that hold the vertical height has gone ..no , sorry not the screw but the screwed hole .
I think that into the hole there just alluminium so it's to easy to strip-oFF  (? right term ?)
You can turn but the screw doesn't go down .
I take the excat replacement from the under of the base (this will be useful if you loose it...), the screws are the same size :
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I've tried with this one
And the story is the same.... the collar remain slightly open , the screw doesnt take place .
I can't find the collar for replacement neither ebay or sme dealer (in their web doesn't showthis part for replacement )
Someone has some tricks ..  suggestion how threading
I use 5/64 hex (I'm not sure I 'm not have around here..) but it's inches , it's right tool
Can someone give the commercial size of the little screwed ?So I could tried with a longer one
Many thanx for your help

Gabriele

[ropie]

I don't know the size, Gabriele, but couldn't you just use a small screw with a bolt to pull the two halves together?

[wesley]

the easy route would be a smaller head screw and nut combo, but can you find something that would fit?  an alternative would be to re-tap the hole for a bigger screw, but would it fit that hole and disappear like it's supposed to?  take the collar to a screw specialist and see what ideas they come up with  .

[ropie]

long screw and nut combo

Yes, a nut, I meant a screw and nut (not a screw and bolt)!

[fetteler]

Hi Gabriele,

If you want to repair your SME collar so it is as good as new then you need to find a local engineering company who can fit a helicoil type insert into the damaged thread for you. Helicoil is a trade name - the Wikipedia has this to say, "A helical insert is an insert made of coiled wire. Another common generic name is screw thread insert (STI), although many users persist in calling them all by a prominent brand name, the registered trademark Heli-Coil."

Google helicoil to find out more. A lot of examples are for large threads but they come in all sizes - plenty small enough for your needs.

It is a very common and simple repair which (in aluminium alloys) makes the thread stronger than it was originally. I'm sure your local expert will be familiar with the technique  and the inserts whatever they are called where you live (after all, Milano is a great engineering city)

I hope this helps.

Steve.

[Rotsch]

Looks like this..... 

[finalvinyl]

If all attempts at finding someone to repair it fail, have a look on Ebay. There are several sellers who list spare parts for SME arms, and I'm sure that you will be able to find a usable replacement at a reasonable price.

[behind the rock]

Cheapest option is a replacement off E-bay.  You would be lucky to find someone with the right size of helicoil and tap required for this repair, if they go down to that size! Cheers.

Andy

[analogadikt]

A watch repairer, who does older, mechanical type of wristwatches may be able to help.

Regards,

[TickOver]

Hi
Has all the thread been stripped out of the hole?
A longer bolt may pick up on any remaining thread and hopefully hold tight...

Cheers

[willbewill]

Lots of metric thread repair kits (like helicoil) on ebay in small sizes eg. M2, M3, M4 etc...

[needlekiller]

he needs only one thread-cutter! the diameter should be one mm more then the diameter of the new srew ! then cut a new thread, buy the srew for the new thread and bingo, prob solved!

[markh]

I have a spare SME collet in my spare box. Let me know if you are interested.

[fetteler]

Lots of metric thread repair kits (like helicoil) on ebay in small sizes eg. M2, M3, M4 etc...

 

Steve.

[sebalele]

Hi
Has all the thread been stripped out of the hole?
A longer bolt may pick up on any remaining thread and hopefully hold tight...

Cheers

dear friends many thanks to all , every cons could be done and the most reliable seem using to new heli insert but not easy to access. the threaded part is behind a collar to fit the head of the screw .(sorry for my poor english) .
For now as suggest , seem that a longer screw close firmly the collar . I can't say for sure but a little thread is still good.
But this will not last long , I have to repair it .
So for now will be use in this way , in the meantine I   will look for tapping tools having just few tenth of millimetre/inch more than the original .
the original screw on SME part list declare 8BA x 3/16 " socket capscrew use 1/16 hex tool .
So thinking about ..3/16 is 1.47 mm could I use a 2mm tap tool ? : I don't know I've to check the standard metrical avaibility, but can be enought around 0,5 mm material spare or more to retap ?