Another neglected aluminium frame

Page may contain affiliate links. Please see terms for details.

Rhythm Thief

Legendary Member
Location
Ross on Wye
This is another one that's turned up in the workshop for "a service". I don't know how long it's been neglected - my guess is since about the early Palaeozoic - but while it looks ok at first glance, the brake caliper mounting bolts are seized absolutely solidly in the frame. I certainly can't get them out with an Allen key and I can't get a drill into them. Anyone got any tips, up to and including destroying the calipers (which are rough anyway)? It seems a shame to scrap the frame.
 

Attachments

  • PXL_20250808_184046666.jpg
    PXL_20250808_184046666.jpg
    296.9 KB · Views: 0
  • PXL_20250808_183535887.jpg
    PXL_20250808_183535887.jpg
    149.6 KB · Views: 0

Paulus

Started young, and still going.
Location
Barnet,
Plenty of penetrating oil and let it soak in for a day might do it. The spaces between the calipers and pivots look pretty corroded. Failing that a hacksaw might suffice.
 
OP
OP
Rhythm Thief

Rhythm Thief

Legendary Member
Location
Ross on Wye
They could be fun to remove, basically it would have helped if on the production line they smeared some grease on the mating surfaces and whoever did the pre delivery inspection and other services should have done the same so you could say it all went wrong at the start

Agreed. One of the things I always always do (and teach others to do) is use assembly grease everywhere. But especially on mating surfaces between two different metals: pedal threads, crank bolts and brake caliper mounting nuts in an aluminium frame. Too late for this frame though...
 
OP
OP
Rhythm Thief

Rhythm Thief

Legendary Member
Location
Ross on Wye
Probably, but if the caliper could be removed an old bolt could be threaded in its place to tap the nut out.

First thing I tried. It's not moving! Once aluminium and steel chemically weld themselves together, they're together forever.
 

Way-Out-West

Well-Known Member
Location
Pinno's attic
There’s an old internet formula 50-50 acetone + automatic transmission fluid, for ‘the ultimate’ penetrating fluid. My personal take on this is they don’t mix together and I feel it’s the low viscosity acetone that does the work. Working on other (non bike) aluminum threaded components, acetone (on its own) has freed parts that seemed impossible to separate. A few drops down the caliper hole might be worth a try. It might soften the paint though.
 
  • Like
Reactions: C R

oxoman

Well-Known Member
You could try either coke or diesel. TBH diesel usually works better if parts submerged. Used it various times on stuff that's been in situ 50yrs plus including dissimilar metals. When I've had issues with aluminium I'll reassemble it rightly or wrongly using an assembly paste. Either copperslip or assembly grease.
 
Top Bottom