Thanks: 0
Likes: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 1 to 11 of 11
Thread: derusting a shaft in a hole
-
2nd May 2014, 09:29 PM #1Product designer retired
- Join Date
- Nov 2006
- Location
- Heidelberg, Victoria
- Age
- 80
- Posts
- 2,251
derusting a shaft in a hole
I have a 22mm ms bar passing through a 20mm thick ms block, and it's rusted in solid.
I have applied heat, from a butane torch, to the block to no avail.
Is there a sure fire solution that will dissolve the rust. WD40 made no impression.
Ken
-
2nd May 2014 09:29 PM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Age
- 2010
- Posts
- Many
-
2nd May 2014, 09:38 PM #2
Hi Ken,
Can you fit it in your electrolysis tank? That would be the most sure fire way I could think of.
Ew1915 17"x50" LeBlond heavy duty Lathe, 24" Queen city shaper, 1970's G Vernier FV.3.TO Universal Mill, 1958 Blohm HFS 6 surface grinder, 1942 Rivett 715 Lathe, 14"x40" Antrac Lathe, Startrite H225 Bandsaw, 1949 Hercus Camelback Drill press, 1947 Holbrook C10 Lathe.
-
2nd May 2014, 09:59 PM #3Mechanical Butcher
- Join Date
- Oct 2004
- Location
- Southern Highlands NSW
- Posts
- 920
Strong acid dissolves rust. A quick bath treatment might do it, but will also attack the steel.
An electroplater showed me showed me this trick, OK for surface rust.
It might not work in your case, if it's inside mating parts.
Jordan
-
2nd May 2014, 10:00 PM #4.
- Join Date
- Feb 2006
- Location
- Perth
- Posts
- 27,837
-
2nd May 2014, 10:29 PM #5
Phosphoric acid shouldn't attack iron too quickly, if you want to go with an acid based attack.
Other than that, there's a DIY recipe of 50% automatic transmission fluid and acetone.
However, I'd splash out for five litres of Evaporust - http://www.evapo-rust.com.au/
-
2nd May 2014, 11:37 PM #6GOLD MEMBER
- Join Date
- Oct 2010
- Location
- melbourne, laverton
- Posts
- 1,469
keep trying
there has been a lot of chat here about transmission oil and acetone mixed 50/50.
is a great rust loosener. if loosener is a word.
can you hit the shaft with a hammer. Id heat spray heat spray and bash with a hammer
aaron
-
2nd May 2014, 11:38 PM #7Product designer retired
- Join Date
- Nov 2006
- Location
- Heidelberg, Victoria
- Age
- 80
- Posts
- 2,251
Can't use a tank
The part I spoke of holds up one end of my roller door, and therefore cannot be removed.
Sounds like Evaporust might be the only solution.
Ken
-
3rd May 2014, 01:00 AM #8Senior Member
- Join Date
- Feb 2013
- Location
- Laidley, SE Qld
- Posts
- 368
I suspect that the butane torch has not got the parts hot enough.
I don't know how it works but I find that heating to red hot with an oxy works just about every time for me. There is the obvious expansion that occurs in the steel of course, but the heat also seems to 'dry out' the rust, the rust in the rusted joint crumbles to a powder. The chemists here will be able to explain it.
EDIT Roller door, house? Maybe red hot is not a good idea.
-
3rd May 2014, 01:09 AM #9GOLD MEMBER
- Join Date
- Sep 2010
- Location
- Lebrina
- Posts
- 1,099
Dead on, butane has nowhere near the thermal output to heat the parts either hot enough or quick enough.
Ideally, you want to heat the outer as hot and as fast as you can, while keeping the inner as cool as you can. Got a friend with oxy acetylene or oxy lpg?
I can possibly add a little to the rust drying out and crumbling question. Iron oxide (rust), has a different expansion rate to steel and therefore it is sort of cracked off and pulverised by the differential in their expansion rate.
-
3rd May 2014, 05:19 AM #10Senior Member
- Join Date
- Feb 2013
- Location
- Laidley, SE Qld
- Posts
- 368
Well there you go, a little googling and it appears that heat does change the composition of rust, it literally dries out.
From yahoo answers
Rust, in its usual hydrated form is FeO(OH).
Rust occurs when iron reacts with oxygen in the presence of water:
4Fe + 3O2 + 6H2O --> 4Fe(OH)3
It "dries" to form the common hydrated form:
Fe(OH)3 --> FeO(OH) + H2O
Water vapor from the air usually is enough to keep most rust as FeO(OH).
When fully dehydrated, rust is Fe2O3
2FeO(OH) --> Fe2O3 + H2O
-
3rd May 2014, 08:29 AM #11
Hi Ken.
I have used methyl salicitate,the good old Oil of Wintergreen liniment ,to good effect.
It crops up in searches for penetrant with some quoting use in US Navy equipment.Its relatively cheap $8 a bottle obtainable at pharmacies
My application was only a small 6mm bolt frozen in its thread. You may have to make a dam of plasticine or blue tack to allow it to wick in.
I know evaporust works very well on surface rust but I understand it must be immersed.
Hope this helps
Grahame
Similar Threads
-
Line shaft
By clear out in forum ANTIQUE AND COLLECTABLE TOOLSReplies: 6Last Post: 9th August 2013, 03:21 PM -
Shaft clearance
By YarrD in forum METALWORK FORUMReplies: 25Last Post: 8th August 2013, 11:37 AM -
Shaft
By vin in forum METALWORK FORUMReplies: 10Last Post: 8th April 2010, 12:37 AM -
Drilling large hole over small hole or vice-versa
By niki in forum HOMEMADE TOOLS AND JIGS ETC.Replies: 28Last Post: 2nd November 2007, 08:32 PM