Home |
Search |
Today's Posts |
#1
|
|||
|
|||
Is it ok to use stainless bolts with aluminium?
Hi
Thanks for replies to my earlier posting about securing my new fairleads. I have managed to gain access to underneath the relevant bit of the boat, so I can hopefully do a proper job viz a vis backing plates. Is it ok to use stainless nuts and bolt with aluminium - if not, what should I use? TIA |
#2
|
|||
|
|||
Stainless bolts and screws is about the only method of securing alum mast
hardware, in my experience. The only exception might be those smaller items secured with alum rivets. I have never dealt with an alum. pleasure but but on all US Navy alum. ship and boats. Stainless bolts are used, however there is always insulators in the holes and under the fitting. In outfitting my mast, I used "Lanolin Grease" on the threads of all my screws and on the faying surface (between the different metals). After 3 years in the water, I haven't noticed any problem with corrosion or siezed threads. I might also suggest that when tapping threads in alum., use a oil especially for this purpose. You can get it at any outfit that speciallizes in machine shop supplies or from major bolt and screw distributor. -- My experience and opinion, FWIW -- Steve s/v Good Intentions |
#3
|
|||
|
|||
Adam wrote:
Hi Thanks for replies to my earlier posting about securing my new fairleads. I have managed to gain access to underneath the relevant bit of the boat, so I can hopefully do a proper job viz a vis backing plates. Is it ok to use stainless nuts and bolt with aluminium - if not, what should I use? TIA Yes, if you don't mind a semi-permanent connection Use TEF-GEL (NOT Tuf-Gel) and the bolts won't become one with the aluminum. If this is an aluminum backing pad and not a cast aluminum fairlead you're talking about, then just drill oversize holes. Evan Gatehouse |
#4
|
|||
|
|||
I agree with Evan Tef-gel http://www.spursmarine.com/tefgel5.htm is pretty
well the standard marine anti-corrosion/anti seize ointment for stainless screws in aluminum. A $12 serine is enough to set every screw on your boat. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com "Adam" wrote in message ... Hi Thanks for replies to my earlier posting about securing my new fairleads. I have managed to gain access to underneath the relevant bit of the boat, so I can hopefully do a proper job viz a vis backing plates. Is it ok to use stainless nuts and bolt with aluminium - if not, what should I use? TIA |
#5
|
|||
|
|||
Steve writes:
I might also suggest that when tapping threads in alum., use a oil especially for this purpose. You can get it at any outfit that speciallizes in machine shop supplies or from major bolt and screw distributor. Also use a spiral tap for "stringy" materials, not a standard fluted tap. |
#6
|
|||
|
|||
On Sun, 01 May 2005 19:52:27 -0700, Evan Gatehouse
wrote: Adam wrote: Hi Thanks for replies to my earlier posting about securing my new fairleads. I have managed to gain access to underneath the relevant bit of the boat, so I can hopefully do a proper job viz a vis backing plates. Is it ok to use stainless nuts and bolt with aluminium - if not, what should I use? TIA Yes, if you don't mind a semi-permanent connection Use TEF-GEL (NOT Tuf-Gel) and the bolts won't become one with the aluminum. If this is an aluminum backing pad and not a cast aluminum fairlead you're talking about, then just drill oversize holes. FWIW: I've retrofitted almost everything with 1/4" aluminum I've custom cut myself (replacing original dished fender washers and "acorn nuts") and that's what I do. Overdrilling the plates by, say, 1/8" allows an easier fit below deck, too. I seal the holes through the deck with epoxy, drill through that, coat the bolts with sealant, coat the piece (say a cheek block) with sealant on the bottom, pop in the bolts, get my wife to hold the SS bolts with a screwdriver, and then I put a bead on the plate below, put the plate on the bolts, and tighten LIGHTLY until I get sealant ooze. Then I lead the sealant set up for 24 hours to a week, depending on what I'm doing. Occasionally this means covering the piece on deck. I dog down the piece snugly and trim with a razor any excess. The key parts are sealing the core with epoxy and coating the shaft of the bolt with a very thin spiral bead. This leaves the head of the bolt sitting in a little ring of bedding and prevents water getting down the shaft, never mind into the core. And the backing plate makes everything a lot stronger due to the spreading of compression forces. R. |
#7
|
|||
|
|||
On Sun, 01 May 2005 20:53:57 +0000, Adam wrote:
Hi Thanks for replies to my earlier posting about securing my new fairleads. I have managed to gain access to underneath the relevant bit of the boat, so I can hopefully do a proper job viz a vis backing plates. Is it ok to use stainless nuts and bolt with aluminium - if not, what should I use? TIA I think it will be fine. If you use enough sealing compound to keep moisture from getting through the deck or into the core (if applicable) out, you will inevitably end up with enough compound on the SS hardware to electrically insulate it from the aluminum. In this thread, the process outlined by Rhys seems pretty thorough and sound to me. When I have done it, I just went ahead and tightened the hardware down without waiting for the goo to cure. And I didn't use epoxy the way Rhys does. If I could do it again, I would probably use something very like Rhys's procedure. --Mac |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Just what is "All Stainless"?? | Boat Building | |||
Aluminium & Stainless Steel off cuts | UK Power Boats | |||
Aluminium & Stainless Steel off cuts | Cruising | |||
Aluminium & Stainless Steel off cuts | Boat Building |