Shim material for swim step bracket

[skunkedskippy]

Hello all. I picked up a used swim step for my 1977 Skipjack (it came off another skipjack). When I bolt the brackets to the swimstep, they don't all lay flush against my transom (about 2 or 3 mm gap). I tried switching the brackets to different positions, but still not all flush. I don't want to fill/redrill holes in the swimstep, so I figured I could shim the gaps with a plastic material, between the brackets and transom.

I was able to source PTFE and PVC shim stock that I could cut and stack to fit. Links below.

Please let me know if this is a good/bad idea, or what other options I have. Thanks!!

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https://www.grainger.com/product/PRECISION-BRAND-Shim-Stock-PVC-42DJ90

 

[Chris1956]

Gee, flat shims? Aluminum plate, big washers, a piece of a walmart plastic cutting board, lots of stuff could be used.

 

[Scott Danforth]

Black UHMW, HDPE or delrin
Black because they are UV resistant
PVC isn't UV resistant

 

[909]

Made some shims recently out of composite decking

 

[garbageguy]

Black UHMW, HDPE or delrin
Black because they are UV resistant
PVC isn't UV resistant

+1 on that. Lots of materials will work on the short term - UV resistance will help in the longer term. In 35 yr experience with large quantities of these materials - some exposed to UV, some not, you can really see it visibly and in lab test data.
As noted above, some HDPE has a black additive package that helps that plastic- material be more UV resistant.

 

[Augoose]

As said, lots of materials you can use. Be sure that you cut your shims in such a way that there is no gap between the bracket and the transom so there's no opportunity for movement or rocking.

 

[Chris1956]

Gee, I would think the Walmart plastic cutting board ($5) would last forever. The question is the thickness, IMO.

 

[skunkedskippy]

Thanks all. I think I have some scrap starboard laying around. I guess I could sand it down to thickness.

 

[Scott Danforth]

Starboard is just an expensive HDPE just like cutting board.

However cutting boards are not UV stable

 

[skunkedskippy]

Today I hung the swimstep up to my transom. Below are pics of the transom/brackets gaps, while pushing the unit by hand.

Do I even need to shim this?

 

[skunkedskippy]

Or, maybe I could shim all 4 brackets, tighten all bolts down the same amount, and the brackets that started with a gap will "squish" a little less than the ones that started flush?

 

[Scott Danforth]

I would slather the back side with a layer of UV4000, bolt it in place

 

[dingbat]

I would start by flattening out the mounting bracket.

Put an 1/8” thick nylon washer under each mounting hole and bolt it up.

 

[skunkedskippy]

I would slather the back side with a layer of UV4000, bolt it in place

Thanks everyone, but this is the best suggestion - I tend to overthink things and make them more complicated than I need to.

Already had 5200, so I marked, drilled, checked fit, slathered, and bolted up.