PPGS Revisited

[Type3Tim]

A while back, over on the "Restored 1930's Auto Shop" thread, Thomas showed how he created a Portable Pedestal Grinding Stand (PPGS).

http://www.garagejournal.com/forum/showthread.php?t=51567&page=277

I was needing a solution for my use and ask Thomas to send me some details. I already had some grinder stands that were fabricated using harrow discs as the base.

View media item 73175
But those harrow discs are sharp and would damage the epoxy/acrylic finish on my floor.

And this one is particularly heavy, to the point I only move it when I'm wearing steel toed.

So I emailed Thomas and ask him for information about the dimensions and construction of his PPGS. He forward me measurements and additional pictures. From that, I drew up the following drawings and set off to see if I could duplicate his fine work.

Plan View:

Top Plate Detail:

Bottom Leg Side view:

But don't launch off on your own build yet. In the next few posts I'll show how it came out, and document a few tips along the way.

 

[BB767]

Re: Portable Pedestal Ginder Stand (PPGS) Revisited

Hi Tim, very nice presentation and your construction plans should help out many others. Here's a link showing how mine looks when finished:

http://www.garagejournal.com/forum/showthread.php?t=51567&page=278

These stands look a little ungainly but they function marvelously. As I mentioned when I first posted about mine, I was motivated to keep my shop clean and by doing all my grinding, wire wheel brushing, polishing etc outside the shop really helps keep it clean inside. The ease of moving a grinder around with this type of stand really aids in that.

Thanks for taking the time to post this information.

Thomas from the Restored 1930's Auto Shop.

http://www.garagejournal.com/forum/showthread.php?t=51567

 

[Type3Tim]

So the first step was to build the three legged base, to see if there is match between the plans and reality. I have a used metal band saw:

And cutting the ends of the legs that meet in the middle, was straightforward.

But what to do about the drastic angle on the end that sits on the floor? Best i could come up with involved a cutoff wheel and working carefully.

(Yes, I know; the guard isn't attached.) While the work was accomplished; this just isn't a satisfactory solution.

Next up, weld the three legs together and see how difficult that is. This was accomplished by sitting the legs upright, in their proper orientation on my welding table. Tacking in place, then welding. First result:

In the picture, it may look ok; but it really isn't satisfactory. None of the three legs actually sit perfectly square with the floor, and the equilateral triangle is also not perfectly parallel to the floor. SO, what to do. Threw the base up on the welding table and turned it over to ponder the situation. Put some welding braces under the legs, put the angle finder on one of the legs.

That's when it came to me; THE SECRET to the whole build of the unit!

"I should place the legs in that orientation when I weld them."

1. Find a perfectly level spot ton the welding table.
2. Draw an equilateral triangle on the table that can be used to match the leg tops up against, in the middle.
3. Set the legs in place, adjusting using the welding magnets.
4. Use a level to check leg-to-leg level (parallelness with the equilateral triangle formed where the legs come together.)

The original welds were cut out, and using this better technique, the base was rewelded.

Next step: How to attach the feet to the legs.

 

[Lx460]

Nice job!

I really like the ceiling mount grinder...

 

[Type3Tim]

Now, how to attach the feet to the legs. The feet were obtained from McMaster-Carr.

The one on the left matches what Thomas used on his build. Here is the link:
http://www.mcmaster.com/#catalog/120/1385/=va3zsz
Part Number 60855K76, currently $3.23 each.

I was also interested in trying out vibration damping feet. The link for the unit on the right of the picture:
http://www.mcmaster.com/#catalog/120/1392/=va42hp
Part Number 6330K21, currently $10.58 each.

In pictures coming in the next posts, you will see that I have used the low cost feet on the front legs, and the expensive vibration damping foot on the back leg. Um,...should have saved my money; it didn't really make any noticeable difference.

Also, I should mention that provided I can build a first PPGS unit successfully, I want to then build 3 additional PPGS units.

I decided on creating a captured nut to screw the feet into. In my left-over metal bin, I had a quantity of 1" wide, 12 gauge (1/8" or close) plate; and a quantity of 1" X 1", 12 gauge (1/8") square tube. The feet have a 3/8" threaded stud; so I picked up a bag of 3/8" nuts at the local hardware store.

I laid out the required number of parts on the plate, drilled holes using my drill press, and the plate was subsequently cut into 1" X 1" parts on the metal band saw.

The square tube was laid out and cut on the band saw. One end of each tube is square, and the other end matches the corresponding angle of the leg it will be attached to. The short side of each(all) square tube parts measures 1/2"

With the help of my good friend Bob; the nut was TIGged to the plate, and the plate was TIGged to the square end of the square tubing. (use a bolt through the plate to hold the nut while welding and then use another nut with a washer to hold the square tube on the plate (over the captured nut) while welding.

After a good bit of fiddling with math, and then just going into "Fabrication Mode" we figured out where to drill an appropriate hole in the leg. This hole being there to create an exit point for the threaded stud of the foot. And thus, a 1/2" hole was place 5/8" from the end of the leg; drilled at the appropriate angle to match the angle of the leg from horizontal.

Then the captured nut assembly was TIGged to the leg.

I can't claim I have any great insight into drilling that hole in the leg. I got through the process with my drill press, an end mill and a drill bit. But it was hard on my drill press. Any other readers who have an insight on this are welcome to chime in.

Next, the plates that the casters mount to.

 

[Type3Tim]

Next I cut a set of caster mounting plates and the mounting plate gussets from 3/8" by 3" wide plate. These were TIGged onto the base. The edge of each mounting plate is 1/2" in from the end of the leg. On this, our prototype, unit I was unsure where the mounting plate should be place vertically. Thomas has a picture that shows that his are offset by some amount, but I wasn't sure if it would work out the same for me. I placed the gusset in the center (vertically) of the mounting plate to evaluate.

TIGging these proved to be challenging due to the tight space at the tip of the gusset.

We mounted the casters and feet and evaluated the effort. Not bad, useable, but the mounting plate is to low. We were able to offset by screwing the feet out; but we will correct this in the final build.

I cut a sample vertical pipe pipe and set it on the base to evaluate.

Feeling Confident, we decided to go into production.

 

[Type3Tim]

Three sets of base components were cut and prepared.

A jig was created for drilling the holes in the caster mounting plates.

This is definitely a place where you need to measure multiple times before committing. If you are right, the work is going to go fast. If you are off a bit, the mistake is going to go fast.

Here is a complete set of parts for one base:

Notice what we did about the floor end of the legs. Thomas suggested that since feet were being use; the radical angle cut was not needed. Just cut them off square. As usual he was correct.

Detail of the floor end with the captured nut parts:

Detail of the base center ends showing the angle difference between the long leg and the short leg.

The top plate that Thomas used is pretty much a square. I opt-ted for a rectangular base. I obtained a piece of 3/8" X 10" wide and a piece of 3/8" X 8" wide. I was only just barely able to cut the 12" on my saw. It required cutting halfway through and then flipping the stock over and cutting the remainder. This is not a method for producing square cuts!

This is going to require some help.

I have a friend who has a home machine shop. I produced the following drawings to show him what I wanted.

The two slots will handle most universal mount devices. The four holes are set up for a legacy craftsman grinder I have. A future improvement would be to handle a wide variety of units by having a slot @ 45 degrees, coming in from each corner. Here are the finished plates which my friend produced at a reasonable cost.

What to use for the handle?

I'll have to say that when I saw this picture on the "Restored 1930's Auto Shop" thread

All I could think was, "I can't believe Thomas junked all those PPGS handles!"

Next up, the final push; the big build.

 

[Type3Tim]

So having all the parts kitted up, the day was selected to put the rest of the PPGS fleet together. The handles had been formed by cutting the ends off the tire irons, and using a torch to heat and bend the handles to spec. The kick bar was made from some 1" od, 12 gauge tube available from the spare steel pile.


To summarize:

• The base legs are C3X5 Channel.
• All of the plate components are 3/8" thickness.
• The vertical tube(29.5" long), kick bar, nut capture parts; are 1/8" thickness

In the final build, the captured nut assemblies were TIGged, and TIGged to the legs. All other welds areMIGged.

Caster Mounting plates were drilled and tapped; so the casters bolt directly to the mounting plate without a nut on the backside.

Here we are set up for a base unit.

The gussets were attached on a center line, 1-3/4" from the bottom of the caster mounting plates. And the tip of the gusset is 1/2" from the end of the leg.

My sidekick Bob, ready to ... I'm not sure what Bob was ready for just then.
View media item 73173Ah yes, He was ready for me to get to work.

Tubes were welded to the bottom of the mounting plates, tubes welded to the bases, handles welded to the mounting plates; in that order.
Grinding and clean up:

And here is the fleet:

Subsequently, a trip to the powder coat shop

===============================================

My thanks to Thomas for sharing the measurements and details of his original build. My fleet of stands accomplishes what I need: being able to park equipment in a compact manner and roll it out when needed:

===============================================

Only one change if I build a second fleet: Move the kick bar out and additional 2" (i.e. the measurement in the drawing above would be-5-1/4")

Here is a link to a video for those interested: http://s95.photobucket.com/user/type3tim/media/IMG_1028_zpsipkbjhtq.mp4.html?sort=9&o=50

Thanks for reading.