Best way to restore a CJ chassis? - JeepForum.com
 2Likes
  • 1 Post By EricRThompson
  • 1 Post By Axhammer
 
LinkBack Thread Tools
post #1 of 10 Old 06-21-2021, 08:15 AM Thread Starter
finsfree
Registered User
 
finsfree's Avatar
1980 CJ7 
 
Join Date: Nov 2018
Posts: 43
Best way to restore a CJ chassis?

Hello,

I am fairly new to the whole jeep CJ world and now I am up to my elbows into it.

Bought my first CJ7 three months ago and not really knowing what to look for I am now in the process of replacing the chassis. I found a used stock one in really good shape, but it needs to be stripped down, cleaned, primed and painted.

What is the easiest way to do this (I know it's a lot of work)? Would a wire wheel (cup) on a grinder work well cleaning the chassis off?

I know there are a bunch of products out there, but do you think will work?

Thanks,

finsfree is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 06-21-2021, 09:04 AM
EricRThompson
Registered User
1979 CJ7 
 
Join Date: Oct 2018
Location: Chalfont, PA
Posts: 147
Garage
I personally would have it blasted. You'll spend a ton of time grinding it by hand. Time = $.
CJWoodman likes this.
EricRThompson is offline  
post #3 of 10 Old 06-21-2021, 09:11 AM
CJ7-Tim
Real Jeeps have dents
 
CJ7-Tim's Avatar
2000 XJ Cherokee 
 
Join Date: Apr 2002
Location: out in the garage - Minneapolis
Posts: 29,063
Have it sandblasted. The cost is not great, and the results are far superior than any Do It Yourself methods, not to mention the time savings.

“We the people are the rightful masters of both Congress and the Courts,
not to overthrow the Constitution but to overthrow the men who would pervert the Constitution” Abraham Lincoln, 1859.
CJ7-Tim is offline  
 
post #4 of 10 Old 06-21-2021, 09:17 AM
OCDXJ
Registered User
 
OCDXJ's Avatar
2001 XJ Cherokee 
 
Join Date: Aug 2020
Location: East Carbon
Posts: 505
Garage
Have it blasted, after doing a 75' Cherokee Chief with wire wheels and other various things it took a very long time and you still can't get into all the tight angles around all the brackets where you need to remove all the rust and have a good paintable surface.

01'XJ,4.0l,AW4,NP231,D30,CHY8.25,3"IROlift,Bilstei n's,IRO OTKsteering,245/70R16,NokianRotiiva AT
OCDXJ is offline  
post #5 of 10 Old 06-21-2021, 10:20 AM
Fourtrail
Registered User
1974 CJ6 
 
Join Date: Dec 2007
Location: Illinois
Posts: 5,275
Look to see if you have a local dustless blasting company. Most are self contained, they will pull the trailer to your house, blast everything clean, sweep up the residue and go on to the next task. The dustless also will not crate the heat that sandblasting does and possibly warp thin body panels.

80 CJ-5, 74 CJ-6, 56 CJ-5
Fourtrail is offline  
post #6 of 10 Old 06-21-2021, 12:22 PM Thread Starter
finsfree
Registered User
 
finsfree's Avatar
1980 CJ7 
 
Join Date: Nov 2018
Posts: 43
Quote:
Originally Posted by Fourtrail View Post
Look to see if you have a local dustless blasting company. Most are self contained, they will pull the trailer to your house, blast everything clean, sweep up the residue and go on to the next task. The dustless also will not crate the heat that sandblasting does and possibly warp thin body panels.

"Dustless Blasting"...? I have never heard of this?

I just watch a youtube video on it...impressed.

Is it expensive?
finsfree is offline  
post #7 of 10 Old 06-21-2021, 12:41 PM
CJWoodman
Registered User
 
CJWoodman's Avatar
1983 CJ8 
 
Join Date: Mar 2017
Location: Cheshire
Posts: 241
Garage
Quote:
Originally Posted by finsfree View Post
"Dustless Blasting"...? I have never heard of this?

I just watch a youtube video on it...impressed.

Is it expensive?
Here is the info from their site.

Most of our business owners make around $300 per hour of blasting.

I am sure there are swings in that number based on where you are but if you are in an area that commands $300 per hour for dustless a conventional blaster in that same market might charge $75 to $100 per hour. Plus you have to get the body to the conventional guy, so there is the cost of transporting the body while the dustless comes to you.
The difference may not be that big considering transportation.

Big Ugly cJ8 build in progress

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeep Air

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CJWoodman is offline  
post #8 of 10 Old 06-21-2021, 01:30 PM
Axhammer
Web Wheeler
 
Axhammer's Avatar
1985 CJ7 
 
Join Date: Aug 2018
Location: Moyock
Posts: 2,125
Garage
I believe it really depends on what kind of shape or condition the frame and/or chassis parts are in, before you can decide whether or not anything needs to be blasted. You will find out more after doing a thorough tear down, cleaning & visual inspection. Some rigs are total rust buckets, and some are “middle of the road” with some severe rust, but rust free for the most of the rest of it. Some are relatively rust free, and your description sounds like you found a good replacement, that is relatively rust free.

The frame under my CJ-7 came from CA via NM, so it has benefited from being exposed to a dry climate it’s entire life, in addition to no salted roads in the winter, which means less rust. It doesn’t have any rust that I have seen, but it probably has some under the shock mount brackets and in the interior.

I just bought a used frame from a Jeep wrecking yard, and it was advertised as being “in Very Good Condition”. When I got to the wrecking yard, all of the frames were lined up in the grass. I could tell they had recently mowed the grass, and then placed all of the frames in a row, so it was easy to compare one to another the way they had them lined up. There had to be at least ten frames lined up. I wish I would have taken a picture of them. Anyway, at first glance they all looked pretty rusty.

While waiting for the owner to come over and show me which frame, I had just driven 100 miles to buy, I looked them all over. After eliminating the the CJ-5 frames, and the CJ-7 NT frames, I probably had about five CJ-7 WT frames to compare. The rust buckets were easy to see, a couple others looked similar, but the more I looked the remaining frames over, the more I realized which frame was the best. When the owner came over, he had to do what I had just done, and find the best frame. I guess they had just recently moved all of the frames, so he had to find it. Again, the point I am trying to make iis, they all looked pretty rusty at first glance.

When I knew which frame I was there to buy, looked it over real good, haggled the priced down a little, and bought it.

When I got it home I performed a tap-test with a small ball peen hammer. This is a method used to inspect aircraft composite parts for delaminations. It is a form of Non Destructive Inspection, and I should have done it before I bought it. After tapping everywhere I have determined my used frame is in fact structurally sound. You can tell by the sound that the metal is solid. I suggest you do a tap test, after you have your frame, stripped, cleaned & inspected. This will help you find rust and thin spots from rust.

The rear cross member on my used frame has severe rust at the body mount locations, so I will replace it. The good thing about replacing the rear cross member is, I will gain access to the interior of the aft frame when I remove the rusted cross member. I will also “French in” my spring mounts, allowing more access to the interior of this frame. If I find thin metal due to rust, I will fix it, so cutting up my frame to modify it will have a hidden benefit.

Blasting a frame is probably the preferred method, but if it isn’t full of rust you may be able to do a decent job with wire cups, and discs with a SS toothbrush for the tight spots. After you have cleaned the metal, there will still be some rust you can’t remove with a wire wheel or brush. You can use a rust converter to stop it in its tracks. The same goes for the interior of the frame.

Check out this video on YouTube for a method that doesn’t require blasting.

I like that he takes the time to address rust on the inside of the frame, and then treating it. I believe it is just as important as what is easy to see on the outside.

Attached Thumbnails
BEFF4147-A459-4122-B3FC-47A65848D62A.jpg   F345EC27-86C1-4CDB-89E3-776C8938344E.jpg  
cjoffroad likes this.

Why do I own a CJ? I like to “Balance the wrench and the steering wheel”
1985 CJ-7 Sebring Red, White hardtop, 284 CID inline six (4.7) TF 999 auto
2020 JLU Black, Black hardtop, EcoDiesel, 35’s on 2” Mopar lift
View my Pontiac in my profile
Axhammer is offline  
post #9 of 10 Old 06-21-2021, 11:15 PM
BagusJeep
Registered User
 
BagusJeep's Avatar
1981 CJ7 
 
Join Date: Jul 2009
Location: Bali
Posts: 8,516
I would have it blasted and then hot dip galvanised. You need to etch the galvanising to get paint to stick to it, chassis black looks nice on the chassis,

You could blast and paint but I would go for a wax process on the inside which consists of applying in turn with a wand attached to a compressor through holes in the chassis:

- rust converter
- water dispersant
- wax

the wax will seal the surfaces from air, so no creeping rust inside out.

BagusJeep lives in Bali with far too many 4x4s:
1981 CJ7 258ci - Bagusjeep
1984 CJ7 258ci - Puthijeep
1981 J20 258ci - Gladys
1951 Willys CJ3A/MB/M38 - Little Willy
1995 Cherokee 4.0 - CHEROKEE
1980 Land Rover Series III 109" troop carrier - ROVER
BagusJeep is offline  
post #10 of 10 Old 06-22-2021, 05:50 PM
Copper_LS_CJ7
Registered User
 
Copper_LS_CJ7's Avatar
1986 CJ7 
 
Join Date: Apr 2017
Posts: 33
Garage
blast it, saves a ton of work. cost me $150 bucks to have mine blasted, then i used Eastwood After blast on it, paint sticks well, used a primer of rust encapsulator then semi-gloss chassis black, i also did the inside the frame paint to keep it from rusting from the inside out.

Check my build out at
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Copper_LS_CJ7 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome