Another hive knowledge ???

[Thumper68]

I have a project coming up where I will need to use the 5/8-11 tapped holes in the fab table to hold the parts in alignment for welding. After going over my options I decided that toe clamps would be nice to use for this, and since I have a mill now and want to play with it making my own sounds like fun.

What stock should I use?

1 1/2 x 1/2 is what my instincts are telling me but since I have never made toe clamps before????

What should the length be? I was thinking 5 inches long with a 2 1/2 to 3" slot for the bolt.

EDIT I got them made, didn't take as long as I thought it would. Here is the video of the process.

 

[nine4gmc]

In for info

 

[Provincial]

Mild steel clamps will bend. I remember using "hairpin" clamps made from 1/2 x 1 flat bar (tall edge vertical) bent into a tight U shape. Using 1/2 - 13 NC studs we could bend them if we pulled hard on a 12" crescent wrench while tightening the nut with a wide washer spanning both sides.

 

[larry_g]

http://www.garagejournal.com/forum/showthread.php?p=6558447#post6558447

In the above thread, on a similar subject, I suggested that the OP look in the TeCo catalog as they have measurements.

lg
no neat sig line

 

[Thumper68]

Thanks Larry, looks like they use 7/8" x 1 1/2" material, I will have to see what my supplier has in stock next week.

 

[Thumper68]

Mild steel clamps will bend. I remember using "hairpin" clamps made from 1/2 x 1 flat bar (tall edge vertical) bent into a tight U shape. Using 1/2 - 13 NC studs we could bend them if we pulled hard on a 12" crescent wrench while tightening the nut with a wide washer spanning both sides.

This is why I asked, even though I don't need a lot of force to hold the work I do only want to make these once.

 

[Superbec]

just buy a set , like on the other thread, it will cost you more in end mills and material than a set costs

and the set comes not only with finger clamps but fasteners also ...

 

[Thumper68]

just buy a set , like on the other thread, it will cost you more in end mills and material than a set costs

and the set comes not only with finger clamps but fasteners also ...

I thought about that and I agree that it would be less $$ to just buy them.

I need a minimum of 14 of them so how many sets is that? my mill has 1/2 slots so they will not work as dual purpose units I don't need the other stuff that comes in the kit and in the end I need the practice on the new mill.


So making my own kills a bunch of birds with one stone.

 

[ducksface]

I tend to buy tooling but make jigs.
Too much making of things just so you can accomplish a required task took the fun out of it for me.
I'd go with mild steel and make them thicker than the commercial ones if I were to make them. Your limited time(so far) on the mill is not conducive(nor will it be fun) to hardened stock.
And
I prefer some flex in my hold downs it allows some cranking on them.

Or
I'd revisit, from a completely different view (like turning the plans upside down) and see if a jig is a better option for your required redundancy. Setting those clamps is not fun once, let alone as many times as you need to.

 

[Thumper68]

I tend to buy tooling but make jigs.
Too much making of things just so you can accomplish a required task took the fun out of it for me.
I'd go with mild steel and make them thicker than the commercial ones if I were to make them. Your limited time(so far) on the mill is not conducive(nor will it be fun) to hardened stock.
And
I prefer some flex in my hold downs it allows some cranking on them.

Or
I'd revisit, from a completely different view (like turning the plans upside down) and see if a jig is a better option for your required redundancy. Setting those clamps is not fun once, let alone as many times as you need to.

I agree I have made many things in multiples and a jig is the way to go for most things and just making a jig to do the work is a learning moment in itself.

 

[larry_g]

https://www.mscdirect.com/browse/tn...Sets-Kits/Fixturing-Clamp-Sets?navid=12108431

Found in the MSC catalog book that the cheap clamps are made from 1018 steel. Have you wandered the MSC to see the different varieties of clamping components? I don't know if they make stepped studs that will fit the 5/8" hole in your table and be able to use 1/2" tooling parts. Maybe some custom coupling nuts that will screw into the 5/8" and have a 1`/2" hole on the other side. I know that I have some odd Tee nuts for using smaller studs in the larger slots.

lg
no neat sig line

 

[Thumper68]

https://www.mscdirect.com/browse/tn...Sets-Kits/Fixturing-Clamp-Sets?navid=12108431

Found in the MSC catalog book that the cheap clamps are made from 1018 steel. Have you wandered the MSC to see the different varieties of clamping components? I don't know if they make stepped studs that will fit the 5/8" hole in your table and be able to use 1/2" tooling parts. Maybe some custom coupling nuts that will screw into the 5/8" and have a 1`/2" hole on the other side. I know that I have some odd Tee nuts for using smaller studs in the larger slots.

lg
no neat sig line

Larry, I looked at all the commercial clamps and kits and after talking to my steel guy today I decided that making my own for the fab table was the way to go.

I ordered 20 feet of 1 1/2x3/4 mild steel for $70.

The other reason is that these are going to get covered in weld bb's and may even get tacked to parts from time to time.

Of course I am going to have fun making them as well, time learning a new tool is never a waste IMO.

 

[dr_clyde]

I personally would have at least ordered cold rolled. A 20' bar of hot rolled is gonna have a lot of mill scale, which will be a pain to deal with.

In most situations, a regular low carbon steel would be fine. However, if I was going to go through the trouble of making my own, I'd use something a little more harden-able. Soft steel will flex and will have plastic deformation at lower clamping pressure. Something with a higher modulus of elasticity would hold up longer. Maybe a 4130 Pre-Hard or maybe 1045 with some heat treat.

I'd waterjet cut the slot and the side tapers on the toe, then gang them up in the vise and face mill the top taper. The little teeth to engage the stepped blocks would be a pain on a manual mill, but doable with the right tooling.

You are in for a lot of milling, those little steps are gonna take a lot of handle cranking.

This is one of those times where you're better off buying the good ones from the store. Spend your time making tools you can't buy, or at least make expensive tools.

Good luck.

 

[gauder the goof]

Show us what you come up with.

 

[Thumper68]

I personally would have at least ordered cold rolled. A 20' bar of hot rolled is gonna have a lot of mill scale, which will be a pain to deal with.

In most situations, a regular low carbon steel would be fine. However, if I was going to go through the trouble of making my own, I'd use something a little more harden-able. Soft steel will flex and will have plastic deformation at lower clamping pressure. Something with a higher modulus of elasticity would hold up longer. Maybe a 4130 Pre-Hard or maybe 1045 with some heat treat.

I'd waterjet cut the slot and the side tapers on the toe, then gang them up in the vise and face mill the top taper. The little teeth to engage the stepped blocks would be a pain on a manual mill, but doable with the right tooling.

You are in for a lot of milling, those little steps are gonna take a lot of handle cranking.

This is one of those times where you're better off buying the good ones from the store. Spend your time making tools you can't buy, or at least make expensive tools.

Good luck.

I went back and forth on what material to use and decided that the A36 was good enough, I am not going to be adding the notches for a step block, since this is to fixture stuff on the fab table I will have lots of off cuts to use on the free end. If it were for the mill that would be an entirely different thing, then again I don't need 14+ on the mill either.

 

[Thumper68]

Show us what you come up with.

I will, should have them done on Thursday or Friday, need to have the Client project done by Monday or Tuesday.

 

[Thumper68]

Spent a few minutes on Sketch up tonight and did a drawing of what I am going to make, figured that I would post it since this thread is boring without pics.

View media item 71460

 

[Thumper68]

Almost done, got a late start today and of course none of the errands on the way to the shop were quick.

Anyhow, I got the first 3 ops done all that is left for the morning is to mill the 5/8ths" slots for the bolts.

I changed the design a bit as I was setting up, the angles are closer to 40* instead of 45* it just looked better to my eye.

Will have them done in the AM and will post pics then.

 

[Thumper68]

As stated I finished these up this morning and figured that I would post up the pictures while I eat my lunch.

As I mentioned before these are made of mild steel A36 it machined great and I was impressed how well the roughing end mills worked.

Over all length is 5+ inches, I didn't bother to be exact with the length the slot is 2 inches and 5/8ths wide for the 5/8-11 socket head bolts the un-threaded portion of the bolt is .618 so this gives a bit of wiggle room.

I first made a jig to hold the blank at the proper angle in the vise, this worked for all 3 angled cuts, once that was done I drilled a 3/16" hole in the face since I did not have a 5/8ths endmill that was center cutting. I plunged the endmill through the blank and then milled the slot in 3 passes using the power feed and the auto stop, it went real quick.

Over all including the tests I did to get the angle correct it took about 3 hours to make these, not bad for my first real milling job in over 20 years.

It also helped me learn more about the new mill so all is good.

View media item 71526
View media item 71527

 

[nine4gmc]

Those came out great, will you be attempting the step blocks too?

 

[Thumper68]

No, I don't need them for the Fab table, at least not now maybe in the future after I get a DRO on the mill but I'm out of play money for awhile.

 

[matt_i]

Soft steel will flex and will have plastic deformation at lower clamping pressure. Something with a higher modulus of elasticity would hold up longer. Maybe a 4130 Pre-Hard or maybe 1045 with some heat treat.

Hate to be the knucklehead to point this out but its relevant for someone studying in the future, the elastic modulus doesn't change for "steel" if its hardened or soft. The tensile strength does change however, and so a harder steel will be more resistant to permanent bend-deformation and from indenting from things like nuts and washers.

I think one could be a little gentler on the bolt torque on a welding table than a machine tool. The weld table clamping can't overcome deflection of the workpiece from the cooling of the molten filler metal, its just for fixturing until the part can be tacked.

Just to further that, suppose you had two pieces of flat and attempted to **** weld them side-by-side, deciding to run a bead the whole way down on one side only, all in 1 shot. The most massive fixture can't take out the tensile stresses which are in the weld...the part will spring as soon as its released. However if it were fixtured and then tacked in several spots, all sides, the part has a much better chance of coming out straight and flat when the final bead(s) is/are run.

 

[dr_clyde]

Hate to be the knucklehead to point this out but its relevant for someone studying in the future, the elastic modulus doesn't change for "steel" if its hardened or soft. The tensile strength does change however, and so a harder steel will be more resistant to permanent bend-deformation and from indenting from things like nuts and washers.

I think one could be a little gentler on the bolt torque on a welding table than a machine tool. The weld table clamping can't overcome deflection of the workpiece from the cooling of the molten filler metal, its just for fixturing until the part can be tacked.

Just to further that, suppose you had two pieces of flat and attempted to **** weld them side-by-side, deciding to run a bead the whole way down on one side only, all in 1 shot. The most massive fixture can't take out the tensile stresses which are in the weld...the part will spring as soon as its released. However if it were fixtured and then tacked in several spots, all sides, the part has a much better chance of coming out straight and flat when the final bead(s) is/are run.

Alright, you got me on a technicality. I'm forgetting some of my college metallurgy. Stiffness is on the slope of the stress/strain curve, and in my head, I was mixing up some terms, as tensile strength is also related to the stress/strain curve. My bad. Its been a few years.

Although my point remains, both a higher hardness and a higher stiffness would be beneficial in this arrangement. Although IMO, the pain of using threaded hold downs is enough to make me forget making my own, and just by some stronghand drop in clamps.

 

[kbs2244]

Why do I think of "The Borg" every time I see this thread.
And then I think of "Barbi Borg."
And then.....

 

[Thumper68]

I added the video link to the OP, but just in case anyone missed it and wants to watch here is the link again.

 

[racingtadpole]

You need to make an adjustable cut stop attachment for your saw next..

 

[Thumper68]

You need to make an adjustable cut stop attachment for your saw next..

I have one but since I have yet to fix the saw to the stand, still working on a few other upgrades, I don't use it.

 

[Lwel9226]

The other reason is that these are going to get covered in weld bb's and may even get tacked to parts from time to time.

Paint them.... nothing fancy, just what ever you have laying around.....
The weld bb problem will be largely eliminated.....

Lynn W

 

[Thumper68]

Paint them.... nothing fancy, just what ever you have laying around.....
The weld bb problem will be largely eliminated.....

Lynn W

I don't like painting anything that is used on the welding table, it is so nice to be able to put the work lead on anything that is handy.