Slide bottom Darco wear marks

[Mikelff]

Originally Posted by Mikendebbie

The bedroom slide in my unit has a single wythe plywood floor (no aluminum framing) as shown in this screen shot from a YouTube video (AZ Expert) replacing a rotten floor of a Montana bedroom slide. I am pretty sure my dining and kitchen hydraulic slide floors have aluminum framing.

I would double check that aluminum framing in the floor?. Most slides only have framing in the walls and roof. The floor is typically 3/4 inch plywood only. If you do have aluminum frame in the floor that’s even better from a strength standpoint, but any new floor will probably have to come out and in from the inside of the slide. Not very desirable.

[Reset19]

Yes, drill a small hole and use some wire to verify. The bands are the aluminum structure within. The plywood is on top of the floor above the aluminum.

[Reset19]

The wear marks in the first picture of this thread outline the aluminum structure where the thin luan flexes underneath the Darco. When I countersunk the UHMW, there was not sufficient threads on the screw to hold in the thin luan plywood layer the Darco was adhered to. Note the living room and bedroom slides are different. I was not comfortable targeting the aluminum tube only for the screws. I chose not to try and use longer screws to penetrate the luan, extend beyond the air gap created by the aluminum tube, and reach the plywood on top that the kitchen cabinets are mounted to.

[Mikendebbie]

Back in June 2023 there was a thread (link below) where I drew the sketches below - trying to figure out what the slide floor construction was. This was only my guess. I have never been able to find a photo from (say) a factory tour showing the slide box structure…and I have not found a YouTube for someone fixing rotten floor in a Montana living room slide where the framing might be exposed. Again, this was a guess…I have no way to verify it or provide dimensions for thickness of the members.

https://www.montanaowners.com/forums....php?p=1275427

[jsb5717]

I might be a cynic, but I’d be surprised if there was any framing at all in the slide floors. Our living, dining slide is single layer plywood. I’d be surprised if it was more than 3/8”. The OEM table pedestal was screwed to the floor and the screws were sticking out the bottom…long since corrected.

Neither the bed slide nor the kitchen slide needs additional framing. The interior cabinetry in the kitchen provides strength to the floor. The bed slide carries the head of the bed and not much weight.

[Baldicon]

Originally Posted by jsb5717

I might be a cynic, but I’d be surprised if there was any framing at all in the slide floors. Our living, dining slide is single layer plywood. I’d be surprised if it was more than 3/8”. The OEM table pedestal was screwed to the floor and the screws were sticking out the bottom…long since corrected.

Neither the bed slide nor the kitchen slide needs additional framing. The interior cabinetry in the kitchen provides strength to the floor. The bed slide carries the head of the bed and not much weight.

I have the same wear marks as MikenDebbie under my kitchen slide. Stud finder show studs at each wear mark, assume they are aluminum. My LR/DR slide and bedroom slide are just one sheet of plywood as far as I can tell.

[Mikendebbie]

I re-read several past posts on the subject of this thread and I drew these sketches to illustrate the differences in my kitchen hydraulic slide and the dining hydraulic slide. My dimensions came from a post from Reset19 who drilled a test hole in the Kitchen slide and measured layers with a nail. Cable or Schwintek slide floors may be different - in fact, my bedroom Schwintek slide has a single layer 3/4" plywood floor.

These sketches are not to scale! I have not confirmed the thickness of the plywood for the Dining slide...3/4" plywood is my guess. My hydraulic slides do not have rollers - only the wear bars.
I took photos of my slides this morning to help with these sketches- but they still are not perfect! It is for illustration purposes only.

Edit: These sketches might help decide what length of #10 stainless steel screws to use with ChuckS darco fix using 1/8” UHMW plastic strips.

Edit #2: I need to get up on the roof and measure the dimension from slide box roof to slide out opening header. The dining slide will need to be jacked up a bit more than the kitchen slide in order to get the UHMW strips pushed in to the end of the slide. I would like to know how much to jack the boxes up.

[Baldicon]

Originally Posted by Mikendebbie

I re-read several past posts on the subject of this thread and I drew these sketches to illustrate the differences in my kitchen hydraulic slide and the dining hydraulic slide. My dimensions came from a post from Reset19 who drilled a test hole in the Kitchen slide and measured layers with a nail. Cable or Schwintek slide floors may be different - in fact, my bedroom Schwintek slide has a single layer 3/4" plywood floor.

These sketches are not to scale! I have not confirmed the thickness of the plywood for the Dining slide...3/4" plywood is my guess.
I took photos of my slides this morning to help with these sketches- but they still are not perfect! It is for illustration purposes only.

Thanks MikenDebbie for your contributions to this thread, I think a lot of us are facing this repair.

[Reset19]

EXCELLENT DRAWING!

Watch the screws that you choose. The screws I bought did not have threads all the way to the head.

[Mikendebbie]

Originally Posted by Reset19

Watch the screws that you choose. The screws I bought did not have threads all the way to the head.

So - should the screws be fully threaded?
Here are some pics i took this morning…

[jsb5717]

Originally Posted by Baldicon

I have the same wear marks as MikenDebbie under my kitchen slide. Stud finder show studs at each wear mark, assume they are aluminum. My LR/DR slide and bedroom slide are just one sheet of plywood as far as I can tell.

As I said, I'm just cynical. It is possible that our kitchen slide has some kind of structure in the floor as well as you seem to have. I haven't investigated it, I just installed the rollers to better carry the weight over the wear bar.

There are also some differences between the Montana and the High Country so who knows. I just know that our Living/Dining slide is so flimsy that you can sit down in a dining chair and spill something on the table. It bounces like a trampoline. So I made an assumption as to how the other slides were built.

Either way, the rollers are a good solution for taking a bit of weight off of the wear bar in the dining slide.

[Reset19]

Please do not look at the photo for anything but a visualization of my comment on threads. It is the only counter sink wood screw I have with me.

I grabbed a box of screws for my project and headed home from Home Depot. The wood screws I bought did not have thread within 1/4 inch of the head.

This type will not have thread to grab the 1/4 plywood in the air gaps between the aluminum frame.

[Baldicon]

Originally Posted by Mikelff

UHMW is probably the best material to use. It’s slick and very durable. You probably don’t want to go more than 1/8” thick. Personally, I would use 3” wide strips with screws on each side of the wearing darco.. If you have any rollers, you will want to use strips that are at least 1/2 inch wider than the rollers, on each side of the roller. I am using 6” wide strips.That darco is cheap stuff and works ok at first but wears fairly quickly. I have cable slides so I need an easy sliding slide out. I used UHMW strips for the rollers on my large slide. My mistake was not jacking up the slide and installing the UHMW to go over the rollers and wear bar. Otherwise your slide rollers have to ramp up onto the strips, and putting some real stress on the mechanism (cables) until it gets onto the plastic. I’m in the process of removing the plastic strips and replacing them with longer ones so that the rollers and wear bar will always be on the UHMW strips. I would recommend anyone using the UHMW method to use strips long enough so that your slide out stays on the plastic strips all the time, in or out. I’m installing the UHMW strips on all my slides. My experience is the slides glide very smoothly and so far no noticeable wear, and saving the darco from having to be replaced. I got my UHMW from Amazon at a reasonable cost. Having to replace the darco will be a lot more expensive than the UHMW plastic strips. Hope this helps.

How long did you cut the strips to go over the wear bar?

[Mikendebbie]

Baldicon - I think my slides are the same depth as yours.
Lift up the carpet in the dining slide inside and you can see the edge of the slide over the white plastic wear bar (re: my first photo in post #30 above). I went out just now and measured mine from the slide edge under the carpet to the back wall surface and got 43.5”. I think that length is what you are looking for. Go outside and look under the slide. There is a steel tube under/below the back wall…which is what I would butt the UHMW against and run it forward to the front edge (after jacking up the slide slightly off the wear bar).

Same measurement on my Fridge slide was 28”.

[Mikelff]

I went about 3 inches past my rollers to the inside. Couldn’t get much further than that. You want to be still inside the rollers when slide is fully extended. You also want to have the rollers sitting on the plastic when the slide is fully retracted. You can probably see on the darco where the slide stops and rests when fully retracted. You want about 2 inches past that to the outside . I don’t have exact measurements so thats the best I can tell you. Just make all your strips the same length on the same slide.

[Mikendebbie]

Here is a sketch of my dining slide showing the 43.5" slide box depth I measured, tube steel support structure, and the TWO plastic slide bars. I got back under the slide this morning to measure the 38.25" between tubes...not completely sure the body edge detail with gray shading is correct, but it is inconsequential to installing a UHMW strip. Hopefully ChuckS or someone else can comment on whether the UHMW needs to extend to cover BOTH slide bars (A and B) - or if it works if only slide bar A is engaged. You should get under your slide and verify these dimensions.

Youtube videos show the commercially available plastic slide skis extending to cover the beveled edge/end of the slide box floor. ChuckS's "Darco Fix" instructions call for the leading edge of the UHMW to be beveled at a sharp angle...so, maybe the beveled edge is adequate to make contact with slide bar B and not completely cover it.

I have not measured or attempted to develop further my sketch of the fridge slide box yet (refer to post #24 and #27 above). There are NO rollers for these hydraulic slides. Cable or Schwintek slides will have rollers, and the slide box floor is a single sheet of ~3/4" plywood (not the framed floor structure shown in post #24). Hydraulic slides have continuous plastic bearing bars. I suppose (in theory) I could place a UHMW strip anywhere along the bottom of the slide where the darco is showing wear. My Fridge slide has SEVERAL darco wear marks along the length of the slide. Apparently my wear marks occur at each slide box floor tube joist location at maybe 16" oc. I will likely have to install 5-6 wear bars. I will pick the worst wear rips to cover. Hopefully I won't have to do all of the wear marks. That is project #8 on my list right now!

[Mikendebbie]

To take this discussion one step further, in another previous thread I had asked a question about how to anchor the UMHW to the slide bottom. ChuckS had used two rows of 3/4" wood screws in his video. In the sketches below I provide two ideas using longer screws. I would appreciate your thoughts on these two options for attaching the UMHW.

Also (I don't recall from ChuckS's video...are the UMHW strips glued to the darco in addition to screwed?

[Mikelff]

I went with Chuck S 3/4 inch stainless wood screws. Reason was the floor is 3/4 inch chip board, and we didn’t want to have the screws go completely through the floor. I have a kitchen cable slide with no rollers that I will put the 3” plastic strips as far inside as I can get them. Like Chuck S, I put screws on each side of the strips. This helps to keep the edges from flexing up when extending or retracting the slide. I thought about putting screws down the middle but was concerned about the possibility of the edges flexing allowing gaps for water to possibly get in. I sealed the edges with 3M marine silicone, which is a lot stronger than most other silicone. Use the clear as they say it is removable. The white is permanent. I have had to remove the clear before, which took some work to get off. I am surprised they used 1/4 inch plywood on the bottom. Doesn’t seem like that would be strong enough to support the weight of the slide. At any rate, just be careful your screws don’t penetrate completely through your floor.

[ChuckS]

Lots of very useful and informative info regarding the slide out floor construction, potential solutions for repairing torn Darco, etc.. Such a great group of fellow Rvers here helping others, sharing info, brainstorming, etc..

My dining room slide out ( 2.5x 2.5 thru the frame hydraulic ) Darco tore on both edges while we were out on a trip about 4 years ago.. No screws, etc had gotten in the way to have caused the unexplained tearing on the Darco only on the forward and aft edges of the slide out Darco material.

I made my "Bush League" repair using the Darco strips just because I wasn't impressed with the slide skis at the time of making the repair.

Not to say the slide skis wouldn't have been just fine.. I just wanted something that I was pretty sure would never wear out ( hence the use of the UHMW strips )

** after about 4 years of in service use with the UHMW strips on the dining side slide I have zero issues with motion, sealing when extended or closed, etc

The Darco outside of where I placed the UHMW strips still looks like new.. No wear detected.

** UHMW strips were sealed along ALL edges prior to installing using RV Black sealant ( Proflex ) with the thought process being the sealant would prevent any water or moisture from being able to wick underneath the UHMW edges

NOTE - the outer edge of the UHMW strips I installed are right at the edge of the Darco where it rolls over the edge of the flooring from the drip strips.. This was the area I had the most concern about water wicking underneath ( black sealant prevents this )

To date .. NO screws along either UHMW strip have ever backed out or broken off..

On the Drivers Side hydraulic slide come the time to repair the Darco when it wears ( none yet after 11 years of use ) I will use the UHMW strips BUT WILL LIFT THAT SLIDE UP and slide the UHMW inward so that it always stays intact with the wear bars the entire slide floor moves against.

** I have not needed to make ANY adjustments to the dining room slide out vertical or horizontal positions to date...

A Repost of my initial video that also shows a short bit of actual motion of the upper guide bar teeth to gear pack teeth mesh engagement ( An area I had concern with ) with contemplating using UHMW strips.. You can see that even with the 1/8 inch UHMW strips in place the gear teeth mesh is perfect...

My old video:
https://youtu.be/EtgzzhXodlk?si=XhjQ4_ZypL7l5rEJ