Plastic mast step - riveting

[Copious]

I'm planning on fitting a couple of these on the mast but am struggling to get the head of the rivet gun into the recessed holes. The single top one is about 9mm deep, the others less so but short of widening the holes I can only assume it needs a smaller head. Slightly nervous about drilling out the holes in case it weakens the step. My smaller rivet gun does fit but is not man enough to pop the Monel rivet! Any bright ideas gratefully received. I am sure these have been used by many of you.

 

[V1701]

Countersink the holes a bit?

 

[WindyWindyWindy]

Rivetnuts and bolt it?

Aluminium rivets are easier to pop..

 

[Rappey]

Use a spacer put over the rivet ,something like a nut or two ? It will be trail and error seeing how long a spacer while still allowing the riveter to grip
I wouldnt countersink as might not look nice

 

[Boathook]

Use a spacer put over the rivet ,something like a nut or two ? It will be trail and error seeing how long a spacer while still allowing the riveter to grip
I wouldnt countersink as might not look nice

I've done the same in the past. As you mention, trial as to how to how many spacers you can use for the riveter to grip..

 

[rogerthebodger]

I used M6 cap head setscrews tapped into the mast.

Initially I did use pop rivets initially but wished to have a stronger fittings

 

[Copious]

Thank you all for those tips. I think a combination of countersinking and using a spacer might work well. I have tried the spacer idea but the ones I tried left no grip on the mandrel. Need to experiment with smaller one.
Roger. When you tapped the holes did you just rely on mast thickness or was it tapped to fit a rivnut?

 

[rotrax]

With three fastnings mast thickness will be fine.

Coat the screws and mast threads with a product to stop electrolosis/gavanic reaction.

 

[rogerthebodger]

Roger. When you tapped the holes did you just rely on mast thickness or was it tapped to fit a rivnut?

I simply tapped into the wall of the mast which was something like 5 to 6 mm thick and with the top 3 holes tapped the shear (pullout) strength of the tapped was more than adiquent

The upper holes screws are in tension with the tapped holes in shear. The lower 2 holes are in compression so contribute little to the pullout load and the shear strength ot the M6 SS setscrew's are owner kill for the load on the steps.

If the thickness of the mast is less you could fit rivnuts. I did not us and any anti corrosion as i felt if the screws corroded the SS screws to the mast it would be safer as the screws would not loosen.

My Mast is 15 meters high deck mounted

The screws I used

 

[Copious]

Rotrax and Rogerthebodger ...Many thanks
Copious

 

[samfieldhouse]

Use a spacer put over the rivet ,something like a nut or two ? It will be trail and error seeing how long a spacer while still allowing the riveter to grip
I wouldnt countersink as might not look nice

I have these exact steps and this is exactly what I did.

I slipped some M5 nuts over the stem of the rivet. Worked a treat.

I positioned mine about 1m from the mast head, which is thr perfect height for me to comfortably service/repair anything up the mast.

I only used 3 of the holes - it seemed like a lot of holes in the mast otherwise.

 

[dunedin]

We have exactly these steps - and had to replace them after 10 years when one snapped off due to UV (fortunately they are low down, for stowing sail cover). I think I drilled out some of the holes to fit a bigger size of rivet. But also used a small nut as a spacer. Tried three pop riveters and couldn’t get to work with the bigger rivets, and in the end had to borrow a professional one.
Interestingly the two extra ones had been screwed on into tapped threads and they seems to work fine. Obviously use something like TefJel to reduce corrosion of dissimilar Metals.

 

[Rappey]

had to replace them after 10 years when one snapped off due to UV

I wondered how long they would last but that wasn't the purpose of the thread so didnt say anything, but now you mention it ....... Seems a lot of work to put steps on that will lead to "when will they snap" anxiety so how about these, and they are cheaper.
I always wanted mast steps but after being on a few boats with them and seeing how so many things get snagged on them I opted for a different option for getting up the mast and its not like you go up there a few times a week ...

 

[Rappey]

Or this type. These are nicer for your hands to hold onto. Cheaper toothed steps can be nasty to hold onto .
Your foot also feels more secure as it cant slip of the side which is a big psychological bonus.

 

[Copious]

Thank you for your input. Very useful,
Copious

 

[ashtead]

Saw this and first thought was surely better non plastic steps might be out there ? I need to replace a broken one but I am reluctant if it will snap like current one.