Correct screw size

[Blackhack]

Probably this is the best place to post this....

Got a bit of a dilemma....The filler screw on my FT cloned version of the russian just spins, which means that it's impossible to fill it from the bottom....If I strip it down, and push the screw from the inside using the allen key, it screws out ok and screws back in, only to spin again...meaning that the internal thread is possibly still ok, but the screw threading itself (and the spare one in the spares kit) is knackered....Does anyone know what the actual size is ??
I can buy replacement screws from evilbay for a couple of quid, but don't know the correct size to buy ???

Any engineers out there help me out ??

 

[anthonyb]

Question: Are you sure it's the screws?
Was the one in the spares kit a new one, or previously used.
I ask for the simple fact the you can get it to unscrew with a little pressure. Which would suggest that the lower threading on the attie is at fault.
As in, the first part of the thread is fine, and when the screw gets to a certain point, the thread on the screw gets below the good bit on the attie. And then the good thread will not re-engage when trying to remove the screw. I think that makes sense.

 

[u8myufo]

I had exactly the same problem with my Hcigar one @Blackhack I found that a terminal screw from a small brass block conncector was just the job to go in. If not have a word with Natasha, she may well have some spares. If not then I have a spare couple of grub screws I can send you if you are stuck, they also fit.

 

[vaporsizer]

By you're description it does sound like it might need re tapping, as in, the hole threads have been over compromised. If it's a grub now ,it could be re tapped & then countersunk, that way you could use a headed screw instead of a grub & it would bottom out flush rather than keep turning.
Does seem strange that a grub would strip the threads under any pressure though unless the the hole is reduced for the final little bit like a stopper. If that's the case then it's been overtightened & stripped the threads that way.

 

[robteifi]

I've had a very similar problem with my FT Russian - except that the screw in the spares pack was a different size - the correct size in fact! The one that was screwed into the Russian was the wrong thread pitch I think and so it stripped the threads after a few refills, and always caught when screwing/unscrewing it - the head was also too small for the countersunk hole.

Not sure how to measure the screw though.

 

[Blackhack]

anthonyb No, I'm not sure if it's the screw or the atty thread, but the easiest (Cheapest) way is to replace the screw and if that fixes it...Well fine...If not, then I either need to buy a tap/die set or just buy another russian, which might be cheaper

u8myufo I dont know about yours, but mine is countersunk, so I dont know if another similar screw would work...If I cant find out the screw size I might take you up on your offer...

vaporsizer It's not a grub screw...just a normal ss threaded countersunk philips type screw...I just think it's the cfheap screws that are mass produced with little or no quality control...




All I need is the screw size and I'll order some up from evilbay....it's about a quid for 50 and another quid or so for postage, so won't break the bank....

 

[vaporsizer]

@anthonyb No, I'm not sure if it's the screw or the atty thread, but the easiest (Cheapest) way is to replace the screw and if that fixes it...Well fine...If not, then I either need to buy a tap/die set or just buy another russian, which might be cheaper

@u8myufo I dont know about yours, but mine is countersunk, so I dont know if another similar screw would work...If I cant find out the screw size I might take you up on your offer...

@vaporsizer It's not a grub screw...just a normal ss threaded countersunk philips type screw...I just think it's the cfheap screws that are mass produced with little or no quality control...




All I need is the screw size and I'll order some up from evilbay....it's about a quid for 50 and another quid or so for postage, so won't break the bank....

Can you measure the screw you have ? I'll throw a couple of guesses at you. M3 or M4.

 

[sparkyjuice]

2.5mm countersunk machine screw on mine
http://www.ebay.co.uk/itm/221262655...eName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
sorry doulbe post

 

[sparkyjuice]

1.6mm panhead for terminals
http://www.ebay.co.uk/itm/221262655...eName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
3mm x 5mm grubscrew for airflow
http://www.ebay.co.uk/itm/321247066...eName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 

[sparkyjuice]

Probably this is the best place to post this....

Got a bit of a dilemma....The filler screw on my FT cloned version of the russian just spins, which means that it's impossible to fill it from the bottom....If I strip it down, and push the screw from the inside using the allen key, it screws out ok and screws back in, only to spin again...meaning that the internal thread is possibly still ok, but the screw threading itself (and the spare one in the spares kit) is knackered....Does anyone know what the actual size is ??
I can buy replacement screws from evilbay for a couple of quid, but don't know the correct size to buy ???

Any engineers out there help me out ??

2.5mm countersunk machine screw on mine
http://www.ebay.co.uk/itm/2212626550...84.m1439.l2649