Use of heat in releasing machine screw

PabloPicasso said:
Thank you. 😊
Click to expand...
I am sure there are circumstances in which boiling water might work but I have severe reservations about the method here. The track is a thick walled aluminium tube 2 - 3 cm square. The bolts holding it down are about 4 - 5 cm long, pass through a considerable thickness of aluminium, then through GRP about 4 - 5 mm thick, then into a threaded aluminium plate.
Heat will be conducted away rapidly by the aluminium. Stainless steel is a poor conductor and the bolts are only 6 or 8 mm diameter from memory. It would be remarkable if the bolts in the aluminium plates achieved any significant temperature.
The OP does not seem to have told us of his attempts to unscrew the bolts with an appropriately sized screwdriver. When I removed the track on my Sadler, very similar or exactly the same as the OP's, the bolts came out easily.
 
vyv_cox said:
When I removed the track on my Sadler, very similar or exactly the same as the OP's, the bolts came out easily.
Click to expand...
That was my thought - everyone seems to be assuming a lot of corrosion, but I don't see any reason to assume it. If the s/s / aluminium interface on the head isn't corroded I would have real hope that the seal under it is also intact. A bit of heat to soften the sealant should do the trick.
 
Ok ok, I'll let the bkiling watee go. If the OP wants to direct heat what about a soldering iron applied to the heads of the machine screws?

A pic from the OP would be helpful.
eddystone said:
Of course it’s not just the s/s screw contact with aluminium of the track itself but with the plate buried in the glass fibre which is a much longer journey for penetrating fluid/boiling water/freezing shock spray. Also wondered if the fact they (presumably) used machine screws with finer pitch than a bolt makes area of converted AI bigger and harder to shift?
Cutting through the machine screws between the bottom of the track and the deck not straightforward as angle grinder won’t fit - maybe Dremel will work
Click to expand...
Can the OP get to the backing plate?
 
eddystone said:
Haven’t been able to get to the boat much but this afternoon after spraying with cold shock fluid the impact driver (manual £17 from machine mart) got one screw started - didn’t have time for more but now more hopeful.
Click to expand...

Patience! Don't rush, you'll get there.
 
eddystone said:
Haven’t been able to get to the boat much but this afternoon after spraying with cold shock fluid the impact driver (manual £17 from machine mart) got one screw started - didn’t have time for more but now more hopeful.
Click to expand...
There's a reason powered impact drivers have become popular.

Borrow or hire one and do use the specific impact driver bits/sockets. Nomal ones jusy crack under the pressure of the hammering they receive.
 
Result! All 8 machine screws removed unbroken and track removed. Irony is that unsuccessful tour of Screwfix, Toolstation etc for a 10mm slotted bit for my power drill driver led me to Machine Mart who offered a £17 impact driver, which actually worked in tandem with stuff that freezes the nut to break the contact - maybe impact driver would work on its own, who knows?
 
eddystone said:
Result! All 8 machine screws removed unbroken and track removed. Irony is that unsuccessful tour of Screwfix, Toolstation etc for a 10mm slotted bit for my power drill driver led me to Machine Mart who offered a £17 impact driver, which actually worked in tandem with stuff that freezes the nut to break the contact - maybe impact driver would work on its own, who knows?
Click to expand...
You could have boiled a lot of kettles for £17. Now we will never know....😀
 
You must log in or register to reply here.

Share this page

Top