M35 rocker panel repair

[lpcoating]

Hello. What is the inside bend radius? Looks like the dimensions are all "outside" dimensions? And to confirm, 18 ga crs, .048" thick?

Guy

 

[gringeltaube]

Hello. What is the inside bend radius? Looks like the dimensions are all "outside" dimensions? And to confirm, 18 ga crs, .048" thick?

• Yes, that's correct: 18 ga crs, (.048")
• Yes, dims are outside. I could take some exact measurements on the finished parts, if needed. What really counts is my diagram on the right: mark work-piece as indicated and center the punch as precise as possible, on each of them.
• Inside radius: I'd say minimum, just what results from using a std. punch & die set for bending #18 ga sheet metal. (I just used what was there in the shop: said to be a 85° punch with a .020" tip radius, on a 86° die with a .472" V-opening)

 

[lpcoating]

I ask about the radius in an attempt to match the original. On the M151 parts, most of the panels are 18ga, .187" inside radius. When you see a repair done with smaller radius, it sticks out a mile away. I have a '54 M221 I could look at. I'd think that would be similar for the radius?

Guy

 

[lpcoating]

Also, all of our presses have CNC controllers / back gauges. Dimensions won't be an issue.

Guy

 

[gringeltaube]

........ When you see a repair done with smaller radius, it sticks out a mile away. ................

True. But in this case there are only two "inward" bends that remain visible - and only with the door open: #3 and #5. None of them is critical, IMHO. Even if these came out too "sharp"; after several layers of paint it sure enough would look "factory stock" again.

For everyone's peace of mind, I will try to measure and compare the radius in question, on different cabs, from different generations/manufacturers, and hopefully still "unmolested"....

Besides the outer rocker panel itself there is also a 90 deg angle piece, made of that same #18 #16ga sheet metal, that closes the rocker panel to the inside and joined with the cab floor. That area usually has rotted away at the same pace and needs to be replaced, as well. I will provide those dims, too. Same goes for the reinforcement U-channel that goes inside the rocker panel and the bracket that connects all this to the door jamb.

For those who have the skills and will to restore their cabs it would be great if all these parts would be offered as a kit.

Here, a few more close-ups while playing with my home-made parts.....

 

[jasonjc]

Some fender patch panels would be nice too. I don't know if there would be a need for just a section like I need or what. Any ideas????

 

[lpcoating]

Put an @ right in front of the username.



Edit to add: I just tried but it doesn't seem to work, for this member....

I think it's because it was listed as "ipcoating. Should be "Lpcoating".

 

[jasonjc]

I think it's because it was listed as "ipcoating. Should be "Lpcoating".

That would be my fault guess I can't read ops

 

[gringeltaube]

That would be my fault guess I can't read ops

Happened to me too - and it's not that we can't read...
It's because the std. font for all our posts makes the lowercase "l" (L as in Lima) and the capital "I" (I as in India) look identical.

I think it's because it was listed as "ipcoating. Should be "Lpcoating".

Yep, you pop up there, 2nd on the list... after typing an LPC in that search window...
Thanks for clarifying.

 

[lpcoating]

I'm having a sample part made. I'll post some pictures of how it looks. Going to use an .060" top die.

Guy

 

[lpcoating]

We should be able to get a sample tomorrow. Hang in there fellas.

 

[lpcoating]

Here is the sample:

 

[lpcoating]

Thank you to Gringeltaube for supplying dimensions. He also sent other related part drawings that I'll look at next week. It was mentioned to make a kit of parts for this repair. That is what I'll look at doing.

Guy

 

[lpcoating]

Okay, I'm struggling. Went through the pictures and prints. Made drawings in AutoCAD of what I interpreted. Numbers aren't adding up as you can see the interference in the drawing.

 

[lpcoating]

All of the dimensions shown are "Outside" dimensions. What part is incorrect? I'm guessing it's the 18 ga profile.

Guy

 

[lpcoating]

Hold those thoughts, went back through the e-mail and think I found the issue. Stay tuned...

Guy

 

[lpcoating]

Okay, this is better.

 

[lpcoating]

The change was from 3.063" to 3.144" on the profile. In this view it's shown as zero clearance, that will be adjusted so that parts properly fit without the use of a hammer. I still have to draw the 7 ga flat pattern but I'm getting there.

@gringeltaube - Gerhard - please review these numbers and verify that I'm correct. Thank you.

Guy

 

[gringeltaube]

please review these numbers and verify that I'm correct.

Working on it right now....




OK, here you go.... See attached drawings, also in PDF, below.
(all to scale & done with the good old MS-Paint )



Also a few more pics....


Dimensions were taken from what I believe is an original section - and those "round" numbers all make sense - but not knowing the factory tolerances, the resulting drawing may not be an exact match to the original blueprint.

Anyway, this should be good enough for our purpose and everything adds up correctly, that way.




Edit: Just added a second drawing now, showing dims of that 90° angle piece, and where it goes, spot-welded in place...

Many thanks to @lpcoating for your dedication and patience...!


Needless to say: this boxed- and not totally sealed- design is the perfect trap for moisture and dirt. No way to flush/rinse all those hollow spaces or even keep them dry, so rust will soon develop there and start "eating" our precious work - unless all parts were phosphatized and then painted with some zinc rich primer, before final assembly.

 

[lpcoating]

So we are in the process of installing a iron phosphate system along with a powder coating batch system and we have a liquid spray booth. So what you mentioned could be an option at CMD.

Guy