Spiral_out

On 1/31/2017 at 11:11 PM, gote said:

Your original idea has a weak point in that the screw will not be perpendicular to the tine at all times. When you turn it it will try to "slide downhill" and bind in the nut. I would definitely pay for the holes if I were you. (and also my piano stool has a single screw)

I planned on a stop welded to the jaw below the screw to prevent this if necessary.  Not sure the 1.5" screws would do much in the way of bending under hand pressure though.  I priced out water jet cut holes, $115 for 2 holes, ouch. I'll look around for someone with a mag drill.

On 1/31/2017 at 11:30 PM, Marc1 said:

I don't know why the OP even bothers with this, buy a post vice I say

Then again there seems to be an obsession in spending a lot in order to spend nothing for some reason that escapes me.

I declare proudly that I avoid making tools of any description I can buy off the shelf if it is of reasonable quality and the price is right. 

However ... giving in to the spirit of the DIY debate ... screw ... piano stool ... come on guys, you have never seen an old round piano stool? I grew up sitting on one of them since age 3 to age 28 when I sold it to buy a rectangular one. It had a screw 1" thick and easy 12" long if not longer. I made the stool top spin fast enough to come off the base countless times. It would make a very good home made vice screw.  

What was the question again? Making a vice? You must be kidding!

A quick search on your US ebay reveals over 10 ads for post vice under $200, many more for under $300. And we all know ebay is top retial price, so gumtree or craigslist will be cheaper.

Craigslist is perpetually empty unless I want to drive a few hundred miles one way to the one vise that has been posted for the last several months.  Not an exciting prospect when the vice could be trash once I get there.  At least this way I'll have similar chances in outcomes with about the same amount of time invested, but I get to spend the time tinkering at home instead of drudging across the countryside.  Point taken though, if this turns into an utter failure I'll probably just buy one from Ebay and move on.

On 1/31/2017 at 11:45 PM, gote said:

That is what I would do but

#1: A guy can be short of funds but have a lot of time and be able to scroung stuff. 

#2: You cannot buy a post vise or a whatnot everywhere. A new postvise of the type where both jaws go down to the ground has probably not been on the market for the last 400 years. 

#3: There is satisfaction in making your own tool.

Definitely a mixture of 2 and 3.  Mostly 3 though.

I appreciate everyone's thoughts on this.  I'll try to get something done on it this weekend and we'll see how it turns out.

7 hours ago, Glenn said:

Your a blacksmith making a vise from fork truck tines. Just weld spokes to the nut and make a wheel. (grin)

Go to the vise section of the site and look for a double screw vise with a chain linking the screws together. No reason to reinvent the wheel.

 

2 screws would be doable, I'll look into that. I saw some cool gears at the scrap yard,  they would make better wheels than I can weld up! 

6 hours ago, KRS said:

About the jaw angles,

you can make them always parallel if you have a sliding front jaw fixed in a box like so:

what you see in this CAD (cardboard assisted design) is the fixed jaw to the right.

It is welded to a piece of tine. the distance from the fixed to the moveable jaw is set by the screw in the bottom. You said you got lots of them.

To prevent the front jaw from rotating when you spin your thing it is boxed in with some flat stock welded to both sides of the ground plate.

The stronger the box is the better you can prevent misalignment of the jaws

I like that idea for parallel jaws.

3 hours ago, JHCC said:

Check out this thread for a lengthy discussion of making a vise from forklift times. 

Regarding your original question, check out the design of the vertical vise.

That makes me wonder if I should be cutting the bend off of the forks and using removable jaws when needed.  More food for thought, thanks.

I've thought about jaw angles and how to control them, but it makes my head hurt haha. I figured I could get the clamping action working, then tweak the pivot at the bottom later to fix any jaw issues.

The impact driver would be my battery powered Milwaukee M18 Fuel. I think they would be able to handle this application, but I'm not sure.  I'll probably try this no matter what method of construction I end up with just to try something I've never seen before.  I'm sure will get old as you say, but I'm only out a nut and some mig wire!

I like the knob idea.  I'll be on the lookout for a good wheel.

I scored some tines at the scrap yard for about $40 and I'm going to make a post vise out of them.   Since I don't have the equipment to put a hole in the tines for the screw to pass through, I was contemplating this design. The yellow tine of course needs to be trimmed a little!  The white 1" plate underneath the nuts will be welded to the stationary leg (the yellow tine), then the nuts welded to that plate. Another plate will be on the top side of the nuts.  The screw will just push against the movable jaw to close the vise.  The hinge at the bottom will probably just be a U passing through both holes with cotter pins to hold it in place.  The bent up plates at the base will probably be cut off unless I can find a useful way to turn them into a mount.

Nothing is purpose cut in this picture aside from the movable jaw being trimmed.  It's all on the table as far as actual dimensions and locations of welds.  The screw is a 1.5" 8 TPI.  That's a little slow so I thought of welding a large nut to the tip of it and making it a power assisted vice using an impact driver or drill. I'd need a wheel or removable bar to allow final tightening by hand though.  I could also just get another screw,  I already have several of these though.

I could drift huge holes using a hole in the ground coal forge for a more traditional design, but I think that's a lot more work than it's worth to me at the moment.  I also see there being an accuracy problem when I'm trying to get the holes to line up.  I can buy an acetylene torch setup to cut holes, but that's not cheap.  Buying a real post vice would be great, but I can't seem to find any locally.

Give it to me straight, am I wasting my time with this?  Should I bite the bullet and hire out someone to make the cuts?  Should I bite the bullet and buy a torch?