Sprinter 4WD Conversion Idea, GMT-800 IFS.

[luthj]

I'm not sure what I will do yet. They still have the mill oil on them, and that needs to come off prior to painting. Painting all the nooks and crannies is going to be a pain. So a weld compatible primer in the tough areas may be worthwhile, just need to see whats available

I need to do a little cleanup at the lead-in cuts, but everything appears to fit right. I think I may have made a small error. I ordered two rack arm braces, but I think I changed one, so they aren't symmetrical. Not a big deal to fab one out of scrap thankfully.

 

[Len.Barron]

while you're still in mock up I'd just keep them lightly oiled (I just use wd40) and whenever I want to tack/weld that area hit it with some brake cleaner(I keep a gallon of acetone to wipe down large areas), after you're confident with differential and suspension fit up you can look at more permanent coatings

 

[luthj]

while you're still in mock up I'd just keep them lightly oiled (I just use wd40) and whenever I want to tack/weld that area hit it with some brake cleaner(I keep a gallon of acetone to wipe down large areas), after you're confident with differential and suspension fit up you can look at more permanent coatings

That's my thoughts as well. I am not going wild with the prep until I am ready to close up the hard to access areas. I expect I will need to make some small to medium changes for fitment. Its time consuming, but better than cutting welds to refit parts.

It's really humid here, so I have a couple days after removing the oil, until the corrosion sets in.

 

[mountainhick]

Yikes, never use brake cleaner on parts you are going to weld. Brake cleaner heated makes phosgene gas, very hazardous Even deadly and there is not effective cure if poisoned.

https://duckduckgo.com/?q=brake+cleaner+welding+phosgene&t=canonical&ia=web

Acetone is fine

 

[luthj]

A good piece of advice thanks. Didn't know that in oxygen deprived environments (shielded by welding gas!) tetrachloroethylene decays when heated. Nasty.

I don't like brake cleaners, especially those with chlorine (tetrachloroethylene). They are skin irritants, and harm some plastics. I generally use carb cleaner or isopropyl alcohol for cleaning. Degreasing I use water based degreasers.

 

[Len.Barron]

Yikes, never use brake cleaner on parts you are going to weld. Brake cleaner heated makes phosgene gas, very hazardous Even deadly and there is not effective cure if poisoned.

https://duckduckgo.com/?q=brake+cleaner+welding+phosgene&t=canonical&ia=web

Acetone is fine

the active ingredient in the brake cleaner I buy is acetone...and if you wait the couple seconds it takes for it to evaporate there isn't any concern at all..

 

[mountainhick]

the active ingredient in the brake cleaner I buy is acetone...and if you wait the couple seconds it takes for it to evaporate there isn't any concern at all..

Thanks, didn't know that was available.

 

[Len.Barron]

CRC Brakleen - 50% Acetone, some Toluene and Methanol as well...there are a bunch of different versions of it, I'm sure the mixture varies..

 

[luthj]

Getting down to business. I need to get some cement board on the table before I start burning in earnest. A little fiddling to get everything to fit. But it looks good so far.

 

[Alloy]

Try to keep the tacs on the OS edges.

Weld tacs on the IS corners are harder to remove (if things have to come apart) and to weld overtop of.

 

[shade]

I started using straight denatured alcohol for a general solvent. It cuts through crap reasonably well, and unless you drink it, toxicity is low.

 

[luthj]

The first issue I ran into. Not enough clearance for the rear LCA bushing. Pretty easily remedied with a bit of cutting though. The front LCA bushing looks good. Its going to need a 3/16" spacer at the front, but I knew that going in.











I got a little practice and dialed in the welder settings on the shock brackets and diff carrier. Not pretty, but it will do. Its a little slow going, as I need to clamp blocks or bushings into the parts, to keep them from moving as the welds cool.

 

[luthj]

Diff is looking pretty good. I don't think I will need to do any cutting. There was enough adjustment in the pre-weld assembly.

I decided to leave the inside of the boxed tubes bare. I am planning on using a body cavity coating, or maybe just the urethane paint with a long sprayer wand. I should be able to get everything painted that way.

I need to pick up some 1/2" bolts for the PS diff carrier bar, should be able to get all that welded up tomorrow.

 

[shade]

Denatured alcohol isn't nearly good as acetone for pre-weld cleaning. First problem is the actual denaturing chemical can vary, although most typically use naphtha, mineral spirits, kerosene or similar. Being a petroleum product it can leave residue. Also alcohol itself actually doesn't de-grease all that well.

I'd have to check the tin of whatever I've been using. It doesn't leave much of a residue, but it isn't 100% pure by design. Good to know about welding prep concerns with it.

I have acetone for some jobs, but for degreasing, I typically stick with water based solutions when I can.

 

[luthj]

My only complaint about acetone, is that it absorbs very quickly through skin, and it eats nitrile gloves. Butyl gloves handle it alright, but they are expensive and annoying to use.

95% isopropyl, followed by dry compressed air seems to work okay. If something is really dirty the caustic water based degreasers work. With Aluminum it will discolor it though, which may not be an issue depending.