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How to build a swivel seat base

2M views 50 replies 33 participants last post by  Adillpickle 
#1 ·
There seems to be some interest in swivel seat bases so I figured I'd do a write up on how to make one.
First of all you need to get your hands on some steel.
I used steel disks because I had these laying around but you could use squares as well, when using squares you need to notch the corners for the lockpin and NOT the sides otherwise it won't turn!

This is rougly what you need:
- 8 inch steel disks or squares 1/4 inch thick
- 6 inches of steel strip about 3/4 wide and 1/8 thick
- 9 inches square steel tube 1/2 by 3/8
- 5/8 lock nut and bolt 2 inch long
- 2 washers
- 2 spring washers
- 1/4 lock nut and bolt 1 inch long
- small spring 1.5 inch long
- 2 1/4 bolts 3/8 long

(Sizes may vary due to use of different sized materials)

I started out with two 8 inch diameter round disks 1/4 inch thick

Marked the center of the disks and drilled a hole where the centerbolt will go.
I used a couple of C clamps to clamp both disks together to get both holes the same.

Notched both disks, I wanted a 180 degree turn so I notched them in 2 places opposite each other.
I did this with both plates still clamped together to get the notches exactly the same. (sorry not picture of this)
After notching them I unclamped them and rotated the upper plate 180 degrees to see if the notches would line up.
They didn't exactly line up so I used a file to get them to line up properly.
You can add one or two notches if you want more positions on the swivel.
Just make sure all notches line up with each other.

Next I mounted the lock bar.
I angled the bar slighty so that it wouldn't stick out.

Reinforced the hinge point for the bar.

Fitted the actual locking piece.
I used the bolt to line both plates up before I tacked it in place.

Welded on two bolts to be able to fit the spring on the lock bar.

This is the bolt I used as a centerbolt It's a 18mm fine threaded 10.9 (grade 8) bolt.
You can use just about any boltover 5/8 diameter I had this one laying around.

And here is the finished swivel piece.
Be sure to put some grease between the plates before assembling them.

Other side.

Just for size reference a lighter on top.

You can weld on a frame to fit the floor and seat.
If there are any questions feel free to ask!
 
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#4 ·
I need a swivel in mine, on the driver side.

Thanks for the How-To, it goes a long way in helping with the build.

You have done a excellent job with the illustrations.

Thanks, Keith
 
#5 ·
Thanks guys!
Just contributing my :2:
 
#8 ·
That's right Bert I made this in the garden shed.
The new shop isn't ready yet.
 
#10 ·
What an amazing bit of work. Since I do not have the facility to do that, I was wondering about the base that "Bread Van" posted here.



Anyone use one of these? Two specific questions;

Is there any play in it? (Does it make the seat rock or sway at all)

What about the 1 5/8" increase in height? Does it make much of a difference?

Thanks,
 
#50 ·
What an amazing bit of work. Since I do not have the facility to do that, I was wondering about the base that "Bread Van" posted here.



Anyone use one of these? Two specific questions;

Is there any play in it? (Does it make the seat rock or sway at all)

What about the 1 5/8" increase in height? Does it make much of a difference?

Thanks,
Thabks for the link to the thread. So many here don't think to provide those, very helpful.

d.
 
#12 ·
markmitch said:
I FOUND IT!!! so does the original seat base sit on top of your design? I ask because I am 6'1 and the wife is 5'7?
This should be stickied.

Mark, I'm sure this will lift the seat. If you look at the connection between the base and seat you'll see this needs more steel to lift and separate,,,,sounds like a woman. Anywho, you'll have some cut and fab work to do.
I changed my seats for subaru seats and they have a longer slide. 4- way manual adj with lumbar support and recline, better seats for my use. I didn't put a swivel but the seat was thicker and brought my legs up to close to the wheel. Swapped the wheel for a smaller diameter chrome and black rubber I found at autozone, made lots of room for getting in and out.
 
#13 ·
I called a company called "Safari Condo" - they used to make conversion camper vans - with swivel passenger seats - out of Astros/Safaris until GM stopped making them in 2005. Now they use the full size vans. They don't convert older Astros anymore, which is too bad, because I would have actually gone there to get my Astro made into a conversion camper van. They're a 9 hour drive away (would have been less than 3 hours if I still lived in Montreal).

The guy there told me they did not install a swivel base on the driver's seat because there wasn't enough room to turn the seat with the steering wheel there. Maybe it depends if the seat was too far forward or pushed back. Or for liability reasons. I've seen both front seats swivel on other GM and VW vans. But he told me they could still install a swivel base on my passenger seat for $400 including parts and installation. They need the passenger seat for about two weeks. If I were further away I might ship it to them, but this spring I will be visiting a friend in Montreal and will be closer to them, so I'll drop off the passenger seat in person. I'll see if they can get it done a bit quicker than two weeks - I don't feel like hanging around that long or making a special trip back to go and get it. $400 may sound steep to those of you who are mechanically inclined, but there's no way I would even attempt something like this. $400 is a bit steep, but not steep enough to discourage me from getting them to do it for me.

In case anyone is interested, here's their website: http://safaricondo.com/index_eng.php
Luckily I speak French (after years of living in Montreal), because they're in a very French, non-English area and the current receptionist doesn't speak English, only French. Just ask for "Parts and Installation please" or "Pieces et Installation, SVP" (pronounced p'yes eh an-stahl-a$$-yon, see voo play) and she'll put you through to the right guy. He speaks pretty good English.
 
#16 ·
Good point , maby you can put them through a test , one end of a log chain bolted to your
rear bumper the other end bolted to the Lazy susan , then a different Log chain bolted to the opposite side of the Lazy susan with the other end wrapped around a big tree.
You drive really fast and if your bumper gets ripped off before the Lazy susan fails we'll Ok em. :lol:
 
#17 ·
Ok recently got my hands on a 92 Astro RS. Love it, the road trips have been a blast and since I love to fish so much it carries all of my gear perfectly.

Now to the topic.

I love this swivel seat idea. I would love to get my hands on one but not for the driver seat but the front passenger seat. Since my girlfriend and I love to road trip as much as possible we spend a lot of time together. She brought up the idea of the seat being capable of spinning around and I told her that yes it was possible and that a swivel setup would be necessary. My girl is "affectionate" lets say so she likes to face me while I'm driving so being able to turn the seat towards me makes this ideal. Does anyone sell this setup or does it need to be fabricated? Is there a drop in bolt on kit?
 
#18 ·
Well this particular kit featured in this topic is a non-standard-fiddle-it-in-yourself kind of thing. I might still have it laying around somewhere though.. At the time I made this one and one more that was a special order for a good friend.

There are however bolt on kits, these can be found on the internet at numerous website.

I would like to express my concerns though, I don't like the idea of the front passenger being sideways in the Van. In case of an accident the passenger would be folded in half in a very unusual way...
 
#19 ·
webcat said:
I was thinking of trying to make some swivel seats out of Lazy suzans that Lowes sales . They'll hold up to 1000 pounds
The problem with this type of bearing is that any slightly off axis weight makes the top and bottom flanges squish together and get stuck. If the load is perfectly centered then it works great. These have a high capacity because of the steel balls, but the rest of it is junk. Add a larger diameter base to the top and bottom and the problem increases 1000 fold.

I have used these for various projects in the past.
 
#20 ·
Dirk said:
Well this particular kit featured in this topic is a non-standard-fiddle-it-in-yourself kind of thing. I might still have it laying around somewhere though.. At the time I made this one and one more that was a special order for a good friend.

There are however bolt on kits, these can be found on the internet at numerous website.

I would like to express my concerns though, I don't like the idea of the front passenger being sideways in the Van. In case of an accident the passenger would be folded in half in a very unusual way...
Understood and noted. But I would still like to go this route. Thanks for your help.
 
#22 ·
#24 ·
I thought I had a little something to contribute to this thread.

I used my original seat base, (2) 15"x15"x3/16" plates of steel and a FWD wheel bearing/hub assembly.

Step 1: Layout and cut holes in plates.
plasma layout1.jpg

plasma hole1.jpg


Step 2: Install hub assembly between plates.
IMG_4683.JPG

IMG_4681.JPG


Step 3: Section OEM seat base and remove material to the height of the swivel plate assembly.
11738017_10155876836535574_4199309426536272022_n.jpg

11742850_10155876838045574_297776585089193782_n.jpg


Step 4: Weld plates in-between the 2 seat base halves.
11751780_10155876838955574_3490531135296413140_n.jpg


Step 5: Clean welds and paint!
IMG_4696.JPG
 

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