Slide Broke

[MAMalody]

Well, here I am on this trip from WA to KY, and we pull in the the Wal-Mart RV Resort in Fergus, MN (SP). We pulled in next to the curb on the side of their lot, nicely marked for trucks and RVs, and I go to put the main slide and bedroom slide out over the grass by the curb we are next to, and the main slide goes cattywampus (yes I did spell that right). My wife told me to stop! We had broken the bolt that went on one end of the transfer rod from between the gears.

The humorus part is a friend of ours owns a Big Sky and was just starting our on a one year tour of the US and I asked if he had a couple of bolts incase one of his slides broke. He had not thought about it and got a couple for his trip.

Anyway, I told my wife to jump under the slide and put in the bolt I had brought along and I would operate the controls from inside. We discussed it a bit, and then in 15 minutes it was fixed and we were up and running. The only real drag was that it was raining, but at lease she stayed dry, after all she was under the trailer.

I am real glad I had those spare bolts and I recommend that if you don't have any, pick them up. There could come a time when you will need them. My wife reminded me she was glad that she had told me to buy a couple of extras and that I had remembered to bring them. (I mean, where would I keep them, after all we live in our 5er.)

[Art-n-Marge]

Would you please post a picture of what bolts you are talking about? I need to put these bolts on the spare parts shopping list.

Thanks a bunch.

[clutch]

I think that is something I need to find out about also. What size bolt and where is it located please.

[Bill-N-Donna]

This is a new one for me also. Would love to see a photo of it; but glad you were able to fix it.

[MIMF]

Art and clutch,

The bolts Mike is talking about are the bolts at each end of the cross-shaft between the gear pack assemblies on the slide room mechanism. It is the 1" square shaft that runs parallel to the frame "I" beam.

The bolts you need are 1/4-20 X 2" hex head grade 8 and they should be zink coated. The nut is a 1/4" nylok or "aircraft" nut. You need 2 for each of the main floor slide rooms The upstairs bed room slide out is a totally different animal and does not use these bolts in the system.

Hope this helps everybody out.

Dale
MIMF

[jimcol]

Thanks to Mike and Dale for the problem and resolution. Will pick some up to add to the spare parts bag.

[racerjoe]

" you told your WIFE to jump under the slide" Would you tell everyone your secret ? The heck with the bolt size !!!

[dsprik]

Thanks, MIMF. This has been a procrastination issue with me since the last time this topic made the rounds (about 1½ yrs ago?). Heaqding to Home Depot in just a few minutes I will take those specs in and stock up.

quote:Originally posted by racerjoe

" you told your WIFE to jump under the slide" Would you tell everyone your secret ? The heck with the bolt size !!!

Joe, He has been reading too many of Richfaa's posts. Rich claims he has Helen do all that stuff - Climb up on the roof, etc. The fact is that Helen is a go-getter and Rich just has get out of the way...

[MIMF]

No problem, Dave. I just noticed I can't spell z-i-n-c.

Oh well, that's what happens when your looking in on these forums at 5:30 in the morning. My 2 cups of coffee hadn't kicked in yet.

[dsprik]

I didn't even notice and I was wide awake in the middle of the day...

Just picked up my bolts. They were grade 8. She said these were not made to shear. Is she correct, Dale? Maybe I got the wrong stuff. I think I asked her for NUMBER 8 not GRADE 8...

[racerjoe]

Grade 8 bolts are a high strenth,with a very high shear factor. I do not think they will shear using them in these applications,not enough stress created with the slide. A grade 2 on the other hand is soft and would bend under stress. I agree that the grade 8 is the best way to go. If the soft one bends, you would have a hard time getting it out

[Trailer Trash 2]

OK ! I think I heard you say "I told my wife to jump under the slide and put in the bolt I had brought along and I would operate the controls from inside" For Real????? If I told or asked my DW to do that I would just get that LOOK, and end up doing it myself.
But I am glag that the broken slide was completed with out a problem.

[clutch]

I do believe that if I told my wife to crawl under the trailer and install a bolt she would insert it some place it shouldn't be.

[MIMF]

Dave,

Grade 8 has to do with the thicknes of the hardness or "durometer" of the steel. They will shear or break. This grade indicates that the thickness of the case hardening goes unto the steel a certain depth. What that depth is, I don't know. All I know is that if you were to break a bolt into, you can actually see the difference in the texture of the steel around the outer surface to a specific depth versus the texture of the steel in the center.

The reason most of these bolts do break is because, Lippert was using originally 1/4-20 X 1 1/4 or 1/1/2" long bolts. Almost always, they were breaking at the thread end.

The way these bolts are made is that it is hardened to a case hardening of grade 8 in this case. Then the threads were machined or cut. In the process of cutting the threads, most of that case hardening was removed with the scrap steel. Thus, the weakness. If the hardening were to be done after the threads are cut, the specs would be out of tolerance. Hardening changes the shape of an object.

Think about that a minute. ;>)

Then one day, it apparently dawned on an engineer at Lippert to use 2" long bolts. That means the shoulder portion of the bolt, which is one inch in length, would pass thru to the other side of the cross-shaft with one inch of the threaded section exposed. The shoulder section of the bolt is the strongest part of the bolt. That almost eliminated the need to replace the bolt once a 2 inch long bolt was installed.

Does all this make sense?

I'll be delighted to explain in further detail at the Great Lakes Rally next month if anyone wants to see a dog-n-pony show.

Maybe a real Metalergist or Machinist can chime in here and correct everything I may have said that was wrong.

Dale

[Art-n-Marge]

Thanks for the bolt information. I just came back from the hardware store to buy some what-nots but didn't see your note. I will put the bolts on a new what-nots list and save it for next time.

For you what-not impaired folk, a what-not is a collection of doohickeys, thingamabobs, doomafliggies and etc, etc, etc's of mostly minor items that we always need, but don't remember to buy them until we run into the situation AGAIN that reminds us to get them - like these spare nuts and bolts (aka zinc coated 1/4-20 X 2" hex head grade 8 bolt and mating 1/4" nylok or "aircraft" Nut).

Thanks for the information!!!

[dieselguy]

Here's a photo of the slide shaft and bolt. The 1/4" bolt is in the center of the photo thru the square shaft just where it transitions into the round shaft.

Two things to note here ... this shaft and gear combination serves no purpose other than keeping both ends of the slide traveling together (no skewing) It's not what drives the slide out. The cylinder (long rod with 3 nuts just above the square shaft) is what moves the slide in and out. Also note the space between the nuts on the cylinder shaft. That space is there for a purpose ... DO NOT adjust these nuts to where they are firmly against both sides of the L bracket! The cylinder has more stroke than the physical travel on the slide ... if tightened as described above, you will break something!

[markwick]

I had this bolt break on me with my first monty fiver and did not have a spare (carry 2 now!), but managed to get the slide back in using a hitch pin., Worked well and easy to put in as long as the bolt holes are aligned. Not recommended for permanent!! but will get you by in an emergency.

[Art-n-Marge]

The picture helped a lot. I notice much of the discussion on bolts are in pairs. Like many things is that because it is better if one breaks, one should replace both so they are the same age?

That said, I think I need to get under there and give it a look. I am not sure I understand how this works or how to replace and install correctly with one of them breaks. I will definitely be looking at these posts a lot closer to get this figured out. I will be doing that soon, because it's time for some preventative maintenance of the slides and I should add some time to review this.

I suppose if MAMalody and wife can do it I'll make sure I am close by so they can help...

Thanks for the info.

[Tom S.]

Are they supposed to shear - like the shear bolts on a snow blower - if the load gets too heavy, to keep from doing damage to the system? If so, wouldn't grade 8's be defeating the purpose?

[grooving grandpa]

Mike, I looked "Cattywampus" up in the Scrabble Dictionary, but couldn't find it. When the bolt shears, do you mean the outside edge of the slide drops "droups" and also does the slide stop moving in or out.

Thanks Lou