Topic: sandblast VS tumbler

[68 GT]

Questioning if I want to rebuild/restore the original upper and lower control arms for our 67 NJ car. If I replace them, they won't have the correct finish. If I rebuild/restore them....I don't have access to a tumbler, I do have access to a sandblaster. Once I get the control arms disassembled and blasted, can I use T9 on them? Would that finish look correct? Or do I really need to find someone with a tumbler to clean up the control arms, rebuild them and then T9 them?

[rockhouse66]

Sorry, but they have to be tumbled to look correct IMO.

[68 GT]

Okay, tumbled AFTER sandblasting or tumble INSTEAD of sandblasting? T9 would be good though?

[CharlesTurner]

Sandblasting will alter the surface appearance too much, making them look grainy.  I prefer to glass bead and then tumble for a uniform appearance.

[68 GT]

Oh, I should find someone to glass bead and then tumble. Oh boy.....thanks. There is a car restoration shop in a town close to me. I have never stopped in there, MAYBE they could help me with glass bead and tumble. Don't know until I ask  THANKS!!!!

[68 GT]

Any suggestions/recommendations on what bushings to use when rebuilding the control arms? Moog?

[J_Speegle]

Questioning if I want to rebuild/restore the original upper and lower control arms for our 67 NJ car. If I replace them, they won't have the correct finish. If I rebuild/restore them....I don't have access to a tumbler, I do have access to a sandblaster. Once I get the control arms disassembled and blasted, can I use T9 on them? Would that finish look correct? Or do I really need to find someone with a tumbler to clean up the control arms, rebuild them and then T9 them?

Allot depends on the condition of the a arms you start with. Another option for some is a simple soak in one of the products like simple vinegar and water, other concoctions or commercial products then finish them as needed

Many roads to the same end product though a poor choice can or will create more work for you in the long run

[jwc66k]

Now don?t take this wrong, but take a minute or two and review the manufacturing, storing and issuing processes for A arms.
The material for an upper ?A? arm (aka control arm) is 0.125in (average, measured in four places) thick cold rolled steel. It may be supplied to the stamping plant as stock on a roll or in 20 foot long, 12 inch wide strips. It is a medium to dark gray in color.
There are several steps that are needed to form the stock into the arm. I won?t go into which step is first, but; several holes are punched; some holes are tapped; in many steps on a 100 ton or larger, stamping press, the arm begins to take shape, bends started, bends continued, bends finished. Bends are a multi-step process. In all these processes, oil is sprayed on the stock to keep the male and female dies from sticking. Some small scratches from the dies are common. Dies don?t last. Remember, there are two arms per car, and how many cars were produced at your plant that used the same arm from the same dies?
At the final stamped step, the arm is chopped off from the roll (or sheet) and dropped into a pile ? more scratches.
It may be stacked and strapped to a pallet ? more scratches. That is possibly the first direct human contact with an individual arm.
The next steps are hands on. The arm is removed from the pallet ? more scratches. The ball joints riveted in place; stacked when done ? more scratches; the upper arm shaft installed; stacked when done ? more scratches. (At this point, my 65-66 upper A-arms were dip painted.) Stacked and strapped to a pallet ? more scratches. Somewhere the ?correct? spring saddle is bolted in. And yes, there were a few ?special ones? of those too.
From there, a forklift ride, stacking, a trip from the stamping plant to a flatbed truck, or a railroad boxcar ? more scratches.
The pallet is unloaded from the truck/car, received at the assembly plant, inventoried, identified (a paint dab?) and made ready for the assembly line (or lines) ? more scratches. Because of the size and weight of several arms, I assume they are stacked loose on a pallet or open front box, delivered and placed on both sides of the assembly line.
The arm is finally bolted to the car ? more scratches ? a spring installed ? compressed ? more scratches (get the picture ? a lot of scratches happen).
When you ?restore? an A arm, it is a working part of your project. All you want to do is to remove unwanted paint and rust. It is not shiny. It is not sterile. It is not a work of art. It is an assembly line item to be installed on one car out of thousands with a lot of steps that can scratch it. There is no way that several million a-arms can be tumbled.
In other words, don?t overdo your restoration. It?s a car you are working on, not the Sistine Chapel.
Jim

[RoyceP]

I started using a local place that does wet blasting with fine glass bead. The specialize in high end restorations of Auburn / Cord / Duesenberg - and that happens to be their name. If the part is not pitted beforehand the results are fantastic. Very smooth parts, you would never guess they had been blasted.


Typical commercial dry sandblasters use a much courser media that results in surface abrasion that is not typical of a new bare metal part.

[jwc66k]

I started using a local place that does wet blasting with fine glass bead. The specialize in high end restorations of Auburn / Cord / Duesenberg - and that happens to be their name. If the part is not pitted beforehand the results are fantastic. Very smooth parts, you would never guess they had been blasted.
Typical commercial dry sandblasters use a much courser media that results in surface abrasion that is not typical of a new bare metal part.

As I've posted before, I've been using glass beads as the media of choice to clean up parts for over 30 years. The next steps are usually paint, phosphate and oil, or off to my zinc plater. I've tried walnut shell but the results were poor. A small vibrator tank (see Eastwood) is also a good tool. I don't do this professionally or daily. Just when I've accumulated enough parts to process.
Jim

[67gta289]

There's a place less than a mile from me that does tumbling for the auto industry - I'm talking about dozens of 10 foot diameter tumblers.  They have a place near Toledo for the "big parts".  I haven't been there in a while but they did small hobby jobs for cash and used those funds to do periodic steak cookouts for the workers.  I had them do several control arms and bellhousings, and they do turn out beautiful.  I've been tempted to buy a tumbler for fasteners, but could never justify something large enough for control arms, let alone a bellhousing. 

[Bossbill]

I've seen vapor blasted bellhousings:
https://www.concoursmustang.com/forum/index.php?topic=9338.msg127690#msg127690

but if you compare the vapor blasted to the light stainless steel wool and light aluminum cleaner, the vapor blasting appears to remove material resulting in pits and overall rough surfaces. These are normally much smoother.
How does this compare to a tumbled bellhousing?

By the way, I use only glass ball media and threw out all my aluminum oxide and black magic style media. Even with glass ball media there is no way this comes close to replicating the finish of a tumbled part.

[CharlesTurner]

I've been tempted to buy a tumbler for fasteners, but could never justify something large enough for control arms, let alone a bellhousing.

Might be surprised...  https://cmtopline.com/


They sometimes get refurbished units, which are a significant savings over new.

[preaction]

I found a used vibratory tumbler from an outfit that does clean outs of closed machine shops unfortunately they are busy, it can do upper and lower control arms easily for $700. Im confident I will be able to sell it and get my investment back.