Custom straps for Mares Quattro+ fins

[zai.gezundt]

Inspired by: Side Mount Scuba Diving - Steve Martin
His main problem with original straps is that large handle snags when diving in caves. I don't have issue with that on account of rarely doing cave diving but two things annoy me:

• Original strap is too tight even after using included plastic extenders. To screw them on was a major pain.
• The handle has a tendency to slide along the strap when fining hard.

Steve's solution is great but it requires specialized clamping tool and, in case of bungee failure, difficult to replace. Also it requires removing small plastic lock on the pin so that bungee fits around the pin snugly.

Instead I used original plastic buckles, 3/4" SS 316 rings, 3/16" shock cord and vinyl tube with 3/8" inner diameter. I am not sure vinyl's ability to withstand prolonged exposure to sun and sea water but time will tell.

P.S. I still have 4 unused SS rings and plenty of vinyl tubing if anybody is interested.

 

[Soloist]

I made a couple pairs of bungee straps for our Mares Quattro fins that are a derivative of your derivative. Incorporating the stainless steel ring into the existing post buckle was a stroke brilliance on your part. I ended up using 1/4 inch bungee because that’s all we had in our dive supplies, so the result is super heavy duty.

 

[Dan]

Thank you for DM me the link to this thread, @Soloist

Thanks for posting this thread @zai.gezundt

I used 5/8” E-Clip (see the top-left of Figure 1, below) instead of the 3/4” stainless steel to keep the 1/4” bungee cord stay in the strap clip. The E-Clip is flat & painted black. It would not interfere the strap female clip installation onto the fin’s male clip.

Figure 1: Modification parts, 5/8” E-Clip (top-left), 1/4” bungee loop inserted into OEM strap screw-in fastener (bottom-left), OEM broken strap with a ball bearing to secure the strap in the OEM strap screw-in fastener (2nd from the left), OEM good strap (rubber hose) screw-in fastener (2nd from the right), OEM female clip (right).

The hard part on this DIY strap replacement work is to remove the broken rubber strap (hose) out of the screw-in fastener. The ball bearing inside the strap locks the strap into the screw-in fastener. I had to put the screw-in fastener on a vice and drilled the old rubber strap out with 1/4” drill bit & push the ball bearing out carefully to not drill through the plastic screw-in fastener.

Once the plastic screw-in fastener is free of the old rubber strap, you can easily squeeze the loop of 1/4” bungee into the screw-in fastener. Then you can screw in the screw-in fastener into the female clip, insert the 5/8” E-Clip into the 1/4” bungee cord loop, and pull the loop back to secure the 5/8” E-clip inside the female clip, as shown in Figure 2, below.

Figure 2: E-Clip is used to keep the 1/4” bungee cords in the Female clip.

Figure 3 shows the OEM fin strap (top) and the modified fin strap with 1/4” bungee cord (bottom). I use 31” long of 1/4” bungee cord to get the 12” long fin strap.

Figure 3: OEM fin strap (top) & Modified fin strap with 1/4” bungee cord (bottom)

Figure 4 shows the modified fin strap (top) with the OEM fin strap (bottom) clipped on the Mares Avanti Quattro Plus.

Figure 4: Modified fin strap (top) & OEM fin strap (bottom) installed on to Mares Avanti Quattro Plus.

 

[happy-diver]

I had to put the screw-in fastener on a vice and drilled the old rubber strap out with 1/4” drill bit & push the ball bearing out carefully to not drill through the plastic screw-in fastener.

Dude for your next one you can cut the speargun rubber, outside the fitting and push the ball out
Even stainless C clips rust out really quickly, the bungee will keep them wet longer than they need

What do you think of the stainless ring idea

 

[Dan]

cut the speargun rubber, outside the fitting and push the ball out

Not sure if I understand what you mean. Have you done it yourself? That ball bearing was inside the rubber hose & pressing the hose against the plastic screw-in fastener.

 

[happy-diver]

Mate get some rings

 

[Dan]

Mate get some rings

View attachment 872131

Ah. I see what you mean. Yes, I did that. Actually I cut the hose at both ends (outside & inside) of the fitting to weaken the hose & drill out the hose until I see the ball bearing, then push it out easily with screw driver.

I’m going to let the E-Clip in there until it’s corroded away then replace it with a piece of Stainless steel rod to keep the bungee loop in the plastic Female clip.

I bet that E-Clip would outlast the bungee cord. I’ll report back here if that E-Clip falls apart.

 

[Umuntu]

Thank you for DM me the link to this thread, @Soloist

Thanks for posting this thread @zai.gezundt

I used 5/8” E-Clip (see the top-left of Figure 1, below) instead of the 3/4” stainless steel to keep the 1/4” bungee cord stay in the strap clip. The E-Clip is flat & painted black. It would not interfere the strap female clip installation onto the fin’s male clip.

View attachment 871927
Figure 1: Modification parts, 5/8” E-Clip (top-left), 1/4” bungee loop inserted into OEM strap screw-in fastener (bottom-left), OEM broken strap with a ball bearing to secure the strap in the OEM strap screw-in fastener (2nd from the left), OEM good strap (rubber hose) screw-in fastener (2nd from the right), OEM female clip (right).

The hard part on this DIY strap replacement work is to remove the broken rubber strap (hose) out of the screw-in fastener. The ball bearing inside the strap locks the strap into the screw-in fastener. I had to put the screw-in fastener on a vice and drilled the old rubber strap out with 1/4” drill bit & push the ball bearing out carefully to not drill through the plastic screw-in fastener.

Once the plastic screw-in fastener is free of the old rubber strap, you can easily squeeze the loop of 1/4” bungee into the screw-in fastener. Then you can screw in the screw-in fastener into the female clip, insert the 5/8” E-Clip into the 1/4” bungee cord loop, and pull the loop back to secure the 5/8” E-clip inside the female clip, as shown in Figure 2, below.

View attachment 871931
Figure 2: E-Clip is used to keep the 1/4” bungee cords in the Female clip.

Figure 3 shows the OEM fin strap (top) and the modified fin strap with 1/4” bungee cord (bottom). I use 31” long of 1/4” bungee cord to get the 12” long fin strap.

View attachment 871933
Figure 3: OEM fin strap (top) & Modified fin strap with 1/4” bungee cord (bottom)

Figure 4 shows the modified fin strap (top) with the OEM fin strap (bottom) clipped on the Mares Avanti Quattro Plus.

View attachment 871934
Figure 4: Modified fin strap (top) & OEM fin strap (bottom) installed on to Mares Avanti Quattro Plus.

I’m not sure why the E Clip was necessary, rather than a stopper knot.

Or why you used two sections of bungee, rather than one … maybe it was easier to size, but that’s what tape measurements are for ?

Otherwise a good DIY !

 

[Dan]

I’m not sure why the E Clip was necessary, rather than a stopper knot.

Or why you used two sections of bungee, rather than one … maybe it was easier to size, but that’s what tape measurements are for ?

Otherwise a good DIY !

Thanks!

How would you put a stopper knot at the end of the rubbery, stretchy bungee cord? There is hardly any space to put anything larger than that E-clip. The OEM plastic Female clip on the fin strap is barely cover the Male clip button on the fin.

Looping a 1/4” bungee cord and squeezing the loop into the fitting is the easiest thing I could see to do. I’m open to any other idea though for my second fin strap.

As of to date I leave the 2nd OEM fin strap as is. Why fix it, if it ain’t broke? Those fin straps are mostly available in dive operators. When mine broke on my last trip, the LOB crew just loan me a fin strap from one of their spare fins.

 

[Umuntu]

Thanks!

How would you put a stopper knot at the end of the rubbery, stretchy bungee cord?

A figure of eight knot holds well as a stopper in bungee. If you tighten really hard it reduces in size and holds well. You would need to leave a bit of tail to ensure it doesn’t work loose.

In shape, a figure of eight knot is longer and flatter than a simple overhand knot, less bulky, and holds better in bungee. When the knot lays flat and tightly tensioned, it should only be a little higher but wider than the diameter of the untensioned bungee cord.

Figure 8 Knot

The Figure 8 Knot provides a quick and convenient stopper knot to prevent a line sliding out of sight, e.g., up inside the mast.

www.animatedknots.com

Bungee does require different types of knots than other types of rope, because of its high elasticity and slippery surface.

Knots and Toggles for Bungee Cord - Small Boats Magazine

There are two special knots that work with bungee; more complex than a sheet bend and a bowline, they hold themselves together and can be easily untied.

smallboatsmonthly.com