# Don't Have 3\4 Aluminum Plate. So We Make It



## tincture500 (Sep 20, 2016)

As an amature hobbist in machinery and the quest to make my own tools, I am making a sissor knurling tool.  Needing 3\4 " aluminum plate I only had  3\8" plate.  What to do!  

I epoxied two 3\8" together.... epoxy spread evenly over the surfaces, clamped in a strong vice.   ---. Wall-la!  3\4" as needed.  Not ideal, however unless exposed to high heat, this should work.  Thoughts.  Tom


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## Cadillac STS (Sep 20, 2016)

Usually there is a bolt and nut that are tightened hard pushing the knurling rollers into the work.  That could be a weak point if you drill the hole for that in the seam of the two halves.  Maybe use a smaller bolt and just put it through one 3/8 inch piece to the lower one.  Or do something to bolster the two halves at that point where the bolt goes through like screws into the halves front and back of where the bolt goes through.  Same with where the knurling wheels go with the split metal you need to have something keeping it from splitting.

Could make it work but you might look into getting some half inch steel with the high pressures needed.  speedy metals or another online site would have what you need for  a few dollars.


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## wrat (Sep 20, 2016)

Without knowing the shear strength of your epoxy, which i'd imagine is not declared anywhere without an equally controlled process, it's a gamble.

It might pass the 'vise test', but there's a lot different dynamic of forces going on when you start knurling.  Heck, there's going to be quite the dynamic forces just making the tool, let alone *using* it.

What I'd be keen to do is just as you've done.  Make up the plate.  Cut out the scissor arms.  Then I'd revisit the arms (if the lamination was still holding) with some kind of pins.  Rivets.  Dowels.  Even hi-loks.  Not bolts, where you'd be bearing on threads, but pins or shafts.  That would keep the layers from sliding (shear) against each other.  

Then you'd have a much better chance of it lasting, IMO.


Wrat


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## Uglydog (Sep 20, 2016)

I wont speak to the extreme tool stress produced in knurling.
However, I'm wondering if there would be any value drilling, threading, and counter boring for some hex cap screws?

However, I'd probably chamfer the edges and TIG it weld it.

Daryl
MN


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## rrjohnso2000 (Sep 20, 2016)

I'm very interested in how this turns out.    I vote that you build as intended and let us know how it turns out. 

I don't know what specific epoxy was used but their use in aeronautics is well proven.


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## tincture500 (Sep 20, 2016)

The Epoxy is the finest quality harbor freight produces. I also have concerns as to the fragilities of the squeeze out I scraped off the edges to mark the layout lines for cut out on the band saw.  If this is a problem I'll deal with it.  The body structure I believe will be fine, but some concern as the the arms that hold the knurl wheels.
The Tig idea is a great suggestion, but no have that either.  I may , if needed add some dome head screws .  Regardless the aluminum is easy to work with my HF mill and 8x16 grizzly lathe.  The DIY experience is well worth the efforts for learn,n in Kentucky.  I have also made a ball turning jig.  I may give this to the wife for the 50th anniversary.


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## Tony Wells (Sep 20, 2016)

There are many parts of a automobile that are held together with adhesives these days. Chemistry has come a long way since superglue. There are some really strong bonding agents. I'd be more concerned about making it out of aluminum in the first place than finding and using a suitable glue. Certainly., additional mechanical reinforcement, whether nuts and bolts, or pins, would have to enhance the assembly though as far as the adhesive goes.


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## RJSakowski (Sep 20, 2016)

You haven't shared your design but if you are laminating the plate to make it more rigid in the transverse direction, it may work for you.  Several strategically placed fasteners to tie the two plates together will help greatly.  The epoxy bond will certainly help controlling shear forces.

The ratchet and pawl on my 4T. come-along are both made from 1/8"steel laminations, held together with rivets.


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## chips&more (Sep 20, 2016)

Why go through all the work, time, money, etc to make it out of laminated 3/8” aluminum. When you will always be up against your project having the big WHAT IF when you go to use it. I would make it out of the proper material to begin with. Can’t be that much if you had to buy it. Or, if you posted a request on this site maybe someone would donate some material. And there are many grades of aluminum, some very soft. Do you know what type you have? Or is it more like a mystery metal? Then that would be a bad start for this kind of project. What costs more? The epoxy or the correct material? But you are thinking outside the box, that’s a good thing, you can do this…good luck, Dave.


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## jocat54 (Sep 20, 2016)

I like the way you think Tom. Use what you have on hand. I have no idea if it will hold up but I would give it a shot.
When I needed a 3/4" aluminum plate for my angle plate for my mill I went thru all my aluminum and didn't have what I needed but had a lot of scraps.So I just melted them and did a lost foam casting. It was a lot more work.


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## hman (Sep 20, 2016)

About the only thing I can suggest, especially if the epoxy joint fails on you, is to sandblast the mating surfaces before re-gluing.  This should improve the bond two ways - (1) clean the surfaces, and (2) give the epoxy some extra surfaces to bond to.  The roughened surface should be especially helpful in resisting shear forces.


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## Subwayrocket (Sep 20, 2016)

Could you have drilled holes thru one plate , then plug welded it to the other ?  Sounds like a pretty cool project either way !   Epoxy is a great thing. Post pics of the project !


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## Cadillac STS (Sep 20, 2016)

Something to consider is that with the action of the knurling process the wheels will directly pull the two halves apart.  And with the need for heavy pressure the aluminum might not hold up long even if it were not split.


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## tincture500 (Sep 22, 2016)

Again, appreciate the comments. The plans URL I'll post.  Project is moving along. Band sawed the shape out last night an will drill the holes for the pivot point today and further refine the shape.  I'm waiting on the knurl wheels to size the placement  of the holes for the shoulder bolts. Plan on using some brass tube as a bearing service for the knurling wheels .   I only have a 8 x 16 grizzle vs lathe and a smalI  HF. Mill.  So cutting steel is possible with tooling , but more than I have at present.  I know some are saying why waste the time with improper material as I can buy a complete sissor knurled for $40.  Hey, I'm a hobbist, newly retired and learning as I go.  Have done advanced wood working also as a hobby for years, but added the metal working machines just recently .  Got the time,ambition but lack the skill of  many professionals on this board.  That's the beauty of this communication board great comments and steerage.  Tom


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## Cadillac STS (Sep 22, 2016)

When you use the scissor knurler there is heavy pressure on the knurls.  brass tube alone might not hold up. You could just use a solid pin. Really great to make the tools yourself. Making the pins is a little lathe job all its own. Need something to hold the pins in like kotter pins or e clips


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## tincture500 (Sep 23, 2016)

As for the wheel axles of the knurl wheels, the plan is to use a brass tube, which drill rod will pass. The brass will hopefully be a bearing surface to the aluminum .  Tom


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## dlane (Sep 23, 2016)

My sissor knurler the hardened pins are pressed into the steel arms , the wheels spin on the pins


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## pineyfolks (Sep 24, 2016)

I'd feel more comfortable with a few 10-32 socket head cap screws and permanent lock-tight along with your adhesive. If that's possible with your design.


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## Dave Smith (Sep 24, 2016)

Tom---I too believe in using what you have at the time---I would just add a few steel rivets to totally bind the two sections together--if you don't have any rivets you just cut some small bolts and rivet them tight---Dave


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