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Hints, Tips and Solutions (Do NOT post requests for help here) If you have any useful general hints and tips for vintage technology repair and restoration, please share them here. PLEASE DO NOT POST REQUESTS FOR HELP HERE! |
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16th Jul 2013, 4:35 pm | #21 |
Dekatron
Join Date: Feb 2005
Location: St.Ippolyts, Hitchin, Hertfordshire QRA IO91UW
Posts: 3,517
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Re: Heating very seized fasteners
Never considered using a TIG for that.....
Interesting concept!
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16th Jul 2013, 6:31 pm | #22 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,799
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Re: Heating very seized fasteners
I changed over to TIG after BOC's last acetylene plant exploded and the stuff became virtually unobtainable. Missing the ability to warm things up in a very focused way I started using the TIG to warm things for bending and for freeing things. It's actually more precise, and with a bit of care I freed a rusted M5 nut the other day.
Best radio use of the TIG so far was rebuilding a sectional aluminium dish that had suffered in the gales 18 months ago. It's back on Mull and has survived a hard winter. David
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17th Jul 2013, 7:37 am | #23 | |
Retired Dormant Member
Join Date: Feb 2008
Location: Auckland, New Zealand
Posts: 631
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Re: Heating very seized fasteners
Quote:
I've shied away from using the primus because of the time it used to take to get it going, but now I have tthe answer to that! Cheers Billy |
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11th Oct 2013, 10:33 am | #24 |
Heptode
Join Date: Oct 2005
Location: Olympia, Washington, USA.
Posts: 663
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Re: Heating very seized fasteners
Another great use for a small torch is to free frozen coil ferrites.
I take an old metal hex wrench and put it in the frozen ferrite cote and then heat It with a small torch or large, very old soldering iron. This can quickly melt the wax, hot glue, or crud holding the core in. Be sure not to grab the metal hex wrench with your bare fingers though. Grab a rag or an old pot holder. Don't ask how I know this.......... This is the only time to try using a metal hex wrench on a coil too. Sort of a go -for-broke Tactic when you have nothing left to do but break the frozen core to remove it. |
17th Oct 2013, 8:55 pm | #25 |
Hexode
Join Date: Jan 2013
Location: Ă…lesund, Norway
Posts: 361
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Re: Heating very seized fasteners
For years I have worked in the automotive trade and have prided myself in being solution oriented, seeing broken off seized and often rusted bolts makes me sad that some do not research this form of problem well enough.
Applying heat to the seized parts is a good idea but do it correctly and use the heat expansion to your advantage. I apply the heat to the bolt and only the bolt (as little as possible heat on the nut) then as it is warmed it will of course expand: Now let it cool and contract. The theory behind this is simple because the xpansion will cause the nut to be stretched by the bolt expanding. If you are foolish enough to try loosening the hot nut then it WILL shear off because it is still seized. (let the nut get cold enough to actually touch) To date I have always managed to remove seized bolts using this method, let the heat work for you. Last edited by Anthony Thomas; 17th Oct 2013 at 9:04 pm. |
21st Oct 2013, 2:15 pm | #26 |
Dekatron
Join Date: Jan 2003
Location: Bradford on Avon, Wiltshire, UK.
Posts: 3,301
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Re: Heating very seized fasteners
Where it is possible(and safe) to do so, I have found heating a seized nut and bolt is virtually certain to guarantee it will be undoable. The only exeptions are where the actual bolt has corroded so badly it has actually become friable. I was always taught to heat the place where the thread meets the nut, and I have never sheared one off yet! It usually just goes "squeak" and it's free.I have even applied a spanner when the nut has been dull red.Of course with studs one has no choice. Works well on all types of things, I have used this on manifold studs(take care if it's in Aluminium), brake cylinder bleed nipples-although of course you can expect to have to fit new seals) even sheared off screws in the outside wall of the house(the heat melts the rawl plug).
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26th Oct 2013, 3:21 pm | #27 |
Hexode
Join Date: Jan 2013
Location: Ă…lesund, Norway
Posts: 361
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Re: Heating very seized fasteners
Thanks for the reaction Tim
If you consider it unsafe to apply open flames to heat bolts etc use "Heat ban" or similar putty to protect the surrounding parts. I have not seen this type of "putty" for a while now so presumably it isn't available any longer, however that is my way of approaching that challenge. I never touch the nut or fastener until it has cooled sufficiently to touch with my fingers, at this point in the proceedings the centre bolt has expanded and stretched the nut suffieciently to allowe penetrating fluid to creep along the threads. "If" you apply a turning force onto the nut before things have cooled there is a real likelyhood that threads will bind up gall and or twist off, be warned! this is the voice of experience talking There is more than one way of doing things, it is down to what tools and knowledge is available. By the way, never apply heat sufficient to cause the metal to "cook" and sparkle as this is far to much heat. Tony Last edited by Anthony Thomas; 26th Oct 2013 at 3:27 pm. Reason: additions |