New mast step

[Alma]

I'm almost ready to install my third new mast step. I need to fair the bilge first since I get a puddle of bilge water forward of the mast occasionally. My original step had shims under it the bilge was so uneven. When I had a new steel step made (#2) I fabricated a wedge shaped piece of fiberglass to make up for the little corrosion I needed to cut off the mast and match the uneven bilge. I had that step powder coated and it started rusting minutes after installation. If ALMA didn't have a tension rod I'd have used aluminum.  I'm lucky to have a friend with a manufacturing company and he made me a new step from 3/8" 316 stainless steel. Since the stainless would ruin the aluminum mast I made a fiberglass cup to insulate and locate the mast on the step. Inside the cup rests a thin aluminum plate to prevent the mast from abrading the epoxy cup. The cup is bi-axial glass oriented diagonally to take the sheer load and I wound roving strands around the outside to tie it together. I'll need to drill weep holes in the cup and silver-dollar sized half-holes at the mast bottom so I can flush it out once in a while with the hot water shower. The 'glass cup is far stronger than the mast section.  I'll need to make a lug on the mast to tie in the bonding wiring since the mast is now electrically insulated from the mast step. I'll also need to make a 1.5" fiberglass block to fit under the step to make up the corroded material I've cut off the bottom of the mast. I have a perfect piece of Starboard but it would cold-flow and shrink over time...

At least this should last a while and the mast's bottom will be high and dry above the bilge.

[Dolce_Vita]

In your first two pictures, I notice there's a significant amount of clearance between the mast section and the walls of the fiberglass cup.

How are you planning to deal with this so the base of the mast can't scoot around as the rigging puts varying loads on the mast high up, and the deck collar acts as a fulcrum?  I figure thats roughly a 7:1 lever arm.

[Alma]

The loads aren't that great. My mast base was pretty wasted and didn't crush. Remember the original maststeps were simply lag bolted with fender washers to the bilge deck. My lag bolts were so rusted they were wasted to nothing and the step didn't move. I actually used a gun-tap and tapped all the way into lead for all-thread studs to locate my adapter plate and the step for my second step. Now that I've faired the bilge I might simply go the lag-bolt route again. If that mast wanted to wander, the rusty old lag bolts and fender washers wouldn't have stopped it. It seemed a worry but in practice I haven't seen evidence of movement. There's actually less room in this new step than the original Pearson maststep. There is also a fillet of roving around the inside bottom not visible in the photo. The fillet locates the mast and centralizes it. If I see evidence of the mast moving within the step I can always shim it with aluminum bent to match the contour of the mast ends. I'd rather keep a little clearance to be able to insure the mast isn't corroding from wet junk between the step ears and the base of the mast. I really don't want to ever have to remove more material from the mast bottom. I'll already have to shorten the tension rod and I'll need to re-tap it. That might be a job I farm out.  I was pleased I was able to extract the tension rod from the aluminum casting at the coachroof partners without problems... Another difference in the photos is how the epoxy cup is now resting against the tension rod mounting bracket. I decided it makes sense to bear against that strongpoint. That 3/8 316 bracket ain't going nowhere! I have an extra 1/4 20 fastener on the front side.

[Dolce_Vita]

I had to shorten and rethread my tension rod too.  I tried to do it but my dies weren't up to the task.  I took it to a machinist, who said it is too hard to thread with ordinary dies, and needs the threads to be cut on an NC mill or a lathe.  He did it for me on the lathe with a couple hour turnaround and only charged me $20!  The toughest problem was finding a machine that had enough clearance to the wall for a 6' rod!

[Alma]

Thanks for the heads-up. I'll take it to a machinist.

[Sea Haven]

Alma,

My boat Surveyor recommended I swap mine out over the next haul or two. I believe it's the original 1978!

My suggestion is that you and your machinist friend there start fabricating these for sale to the rest of the group, thereby earning $$ for boat upgrades!

"Sub" Ed

[Carolina Dog]

Here she is. Alum.

Marcus of Lucky Dog

[StarGazerII]

Guy's, Guy's   Put an aluminum BLOCK witch makes the mast step higher up about 3-4 inches, then install the mast step that's now out of the bilge water.  Now your mast won't corrode and not to say..last longer  Capt Rob
 

[Alma]

Capt Rob's suggestion does not take into account galvanic corrosion so it isn't recommended.

Here's a photo of the almost 10 year old step.

It is the same as when it was installed.