Minneapolis Moline Knoedler Seat Frame

[RCW]

Okay - - given it's a weekend, wish I had the shock yesterday, but no luck. Hopefully today.

I think I'm looking at a 10" spring. Also been estimating travel, and I think it's only about 3" to the rubber stop.

Using ccoon's math (thanks) - - I'm about 240 + 35 lbs frame (great guess) = 275.

Using 50% 275= x lbs/in x 1.5"......therefore x = 183 lbs/in.

These weren't built for comfort, so 200-250 rate should be fine, I think?

I'd be willing to bet that the spring Lil Foot pictured a while back would be real close....

I found a piece of 1/8" plate in the garage. Will cut circles for end plates for the spring, and either stitch in a ring to make a cup, or add 4 small hold tabs. Daren Todd and D2Cat gave me great welding pointers years ago and I've practiced, but haven't had it out yet this year.

I will also have to check travel and OD on the shock when it shows. May drive spring rate and will drive the ID of the the spring.

The picture is deceiving...like the first picture in this thread, the upper plate on the right fastens the frame to the swivel mount bar of the tractor a few degrees off-plumb to the right. I have it about 10 degrees off plumb to the left. Only way it would stand up....

 

[ccoon520]

Okay - - given it's a weekend, wish I had the shock yesterday, but no luck. Hopefully today.

I think I'm looking at a 10" spring. Also been estimating travel, and I think it's only about 3" to the rubber stop.

Using ccoon's math (thanks) - - I'm about 240 + 35 lbs frame (great guess) = 275.

Using 50% 275= x lbs/in x 1.5"......therefore x = 183 lbs/in.

These weren't built for comfort, so 200-250 rate should be fine, I think?

I'd be willing to bet that the spring Lil Foot pictured a while back would be real close....

I found a piece of 1/8" plate in the garage. Will cut circles for end plates for the spring, and either stitch in a ring to make a cup, or add 4 small hold tabs. Daren Todd and D2Cat gave me great welding pointers years ago and I've practiced, but haven't had it out yet this year.

I will also have to check travel and OD on the shock when it shows. May drive spring rate and will drive the ID of the the spring.

The picture is deceiving...like the first picture in this thread, the upper plate on the right fastens the frame to the swivel mount bar of the tractor a few degrees off-plumb to the right. I have it about 10 degrees off plumb to the left. Only way it would stand up....

View attachment 60285

Happy to help. I could be wrong here but I'll mention it and one of the car mechanics on here will definitely chime in if I am way off base. If you combine a shock with your spring it will effectively increase your spring tension (K value in the equation I gave) to an extent (I think).

Here is my reasoning behind this thought (sorry I didn't think of it sooner). The shock absorbers job is to dampen the rebound of a spring. It does this by using an orificed plate attached to the end of a piston that sits in a pool of fluid. As the spring is compressed the fluid gets pushed through the orifices. When the load is removed from the spring and it moves back up the fluid adds resistance effectively slowing its expansion rate and reducing the amplitude on the bounce back.

This fluid would add resistance in both directions (I do not know how much) It might be smart to sit at 190 lbs/in or even 175 lbs/in on your spring to account for that additional resistance.

I definitely oversimplified a shock absorber and I'm sure I hurt a few car guys souls with that explanation, but if I am way off base someone please correct me so I don't contribute to the breaking of RCW's spine due to a too light of spring.

 

[RCW]

Holy smokes....supply chain....

Shock from Club Car Part # was back-ordered. I did get delivered bushings for a shock I don't have....

Ordered and took delivery on an Amazon knock-off shock to get me going....M10-1.25 vs 3/8-24...GRR...

Just wanted to get the spring sized and ordered....guess what...Back Ordered.

At this rate, I may be trying to get a Seat Pan by October....

I will need to thread the rest of both studs, and then shorten them. I’m not a fan of the Amazon replacement, and prefer to do this once.

Geez.....

As an aside, about half of the shelves for Air Filters were empty this morning when I got one for my truck at Advanced Auto Parts.

 

[Magicman]

Well crapper. I was on the road sawmilling last week and hoped to see some good news on this topic when I got back on here. Da paint looks good and that is good.

 

[RCW]

Guessing dimensions, started building the top strap with pins to lock into top frame rail. Making everything long for now.

Welds have been under a grinder, but actually pretty happy with them so far.

 

[RCW]

Ordered another shock from a different supplier....showed up Sunday afternoon 4 days later. No idea it was even shipped.

My hat's off to Cartszone.com for speedy delivery.

Will probably cancel other shock order. Haven't heard from them in 3-4 weeks.

Again, this isn't a tractor part, but a golf cart part that can be made to fit.

At first I thought the Made in China part was 3/8-24 thread. Learned 3/8-24 is very close to M10x1.0...part is M10x1.0, of course.

I can't have M10x1.0 on a 1953 American Tractor.

I re-threaded the M10 to 3/8-24, and chased the threads through most of the studs' length. They'll need to be cut off to shorten the whole assembly.

While threading, the 4 poor spot welds on the cover broke off when in my bench vise.

I spot welded the cover back on, and think it's fastened better than it was before.

My continued thanks to D2Cat and Daren Todd for the welding pointers they have given me over the years.

The Coil Spring is supposed to be delivered tomorrow....I want stuff ready to put together this weekend....Woo Hoo!

 

[Magicman]

Another small step toward gettin-r-done.

 

[RCW]

Coil spring came today.

Starting to look like a Knoedler frame.

Made some 1/8” x 3 1/2” caps. Welded some 1/4” rod to the bottom as a retainer to hold into the spring. Welds aren’t great looking, but they’ll hold.

 

[ccoon520]

Coil spring came today.

Starting to look like a Knoedler frame.

Made some 1/8” x 3 1/2” caps. Welded some 1/4” rod to the bottom as a retainer to hold into the spring. Welds aren’t great looking, but they’ll hold.


View attachment 61588
View attachment 61589

View attachment 61590

Time to paint the spring to match

 

[RCW]

Time to paint the spring to match

Good point.

I will paint/re-paint everything before final assembly.

It will be taken apart several times before I’m done.

I still have to fabricate the top mount that hooks to the side links. I have the parts done, but not cut/welded to final dimensions.

 

[bird dogger]

Nicely done!! You can now offer "kits" for sale!!

 

[RCW]

Couple steps closer.

As I was guessing dimensions, there might not be enough clearance to the bottom of the seat pan.

Not the end of the world. I’ll figure it out….

 

[bird dogger]

RCW, that's looking mighty nice!

 

[ccoon520]

Couple steps closer.

As I was guessing dimensions, there might not be enough clearance to the bottom of the seat pan.

Not the end of the world. I’ll figure it out….

Why wouldn't you have clearance to the bottom of the seat pan? It looks like you have like 2 inches of clearance with the whole thing put together. The whole shock and spring assembly should collapse... Nothing should stick out. Unless there is something I cannot see.

 

[RCW]

Why wouldn't you have clearance to the bottom of the seat pan? It looks like you have like 2 inches of clearance with the whole thing put together. The whole shock and spring assembly should collapse... Nothing should stick out. Unless there is something I cannot see.

True - - I wasn't very clear. The shock was just a little long. I just needed to shorten the studs.

As you said, it will collapse, so no risk of anything hitting/interfering.

The coil spring seems pretty stout. Will be curious how it reacts when I finally get to use it....

 

[ccoon520]

True - - I wasn't very clear. The shock was just a little long. I just needed to shorten the studs.

As you said, it will collapse, so no risk of anything hitting/interfering.

The coil spring seems pretty stout. Will be curious how it reacts when I finally get to use it....

If you have one set a tube of sand on it. See if 70lbs compresses it at all (thinking like an 1/8"-1/4"). if not you might want to pull it and get a slightly lighter spring before you paint it and make it unreturnable.

This would be more of a sanity check than anything and just a suggestion.

 

[RCW]

If you have one set a tube of sand on it. See if 70lbs compresses it at all (thinking like an 1/8"-1/4"). if not you might want to pull it and get a slightly lighter spring before you paint it and make it unreturnable.

This would be more of a sanity check than anything and just a suggestion.

Yeah - - a test is a good idea.

I'm planning on mounting it to the tractor and putting myself in it.

There are two elevation options for the seat bracket, and several fore/aft options for the pan itself. Gets them figured out before paint, too.

Kills a couple birds with one stone.....

 

[RCW]

Test run. Everything is loosely fastened.

Squashed the coil spring like a small bug But I didn’t bottom it out!

I’m happy with the results. Seat is kinda comfy for an old farm tractor.

At 240 or so, I’m probably an atypical tester for the seat’s suspension. Current spring is 200 lb/in. I’m not going to a 250 lb/in to accommodate.

 

[ccoon520]

Test run. Everything is loosely fastened.

View attachment 61708

Squashed the coil spring like a small bug But I didn’t bottom it out!

I’m happy with the results. Seat is kinda comfy for an old farm tractor.

At 240 or so, I’m probably an atypical tester for the seat’s suspension. Current spring is 200 lb/in. I’m not going to a 250 lb/in to accommodate.

Looks great! I guess my recommendation was a little off. Also I just noticed where the PTO shaft is on that machine and good lord I cannot say that I am unhappy with being in a day and age where I don't have to worry about getting caught up in one while bouncing through a pasture. Imagine if a PTO shaft decided to bite the dust while you are sitting there.

Still cool though!

 

[RCW]

ccoon - I posted in another thread about safety features.

Of course, there’s none here.

It makes you pay attention….