Wednesday, July 18, 2018

The Rivet Maker--my latest Makvention.



This is my latest invention that I made. That's why I lay claim to the word makvention.

Anyway, I wish I had thought this out a LOT earlier in my jewelry career.



I sell it as a kit for $280 here

One of the big problem in making rivets is that the commercial rivets that one can buy are very limited in selection and also too large for use in high end jewelry.

So I set about to design a proper rivet maker for myself and in doing so, made a product that is the first of it's kind and also works well.



As with any tool, there is a small learning curve, but once you have made a couple of rivets, it is very simple and easy to use.



The center holder has a removable stop.


The stop is needed to ensure the wire goes down only as far as the die former is deep.



There is a central hole that is drilled through the central holder so it can be pushed out from the bottom just in case some grit or filings jam things up.



The height gauge is there to ensure that the rivets are always cut to the same length.



The three different thicknesses denote 1 mm, 1.6 mm and 2.3 mm and 4 mm.



The wire is cut to the preferred length.



The 1 mm height would produce the smallest rivet head and the 2.3 mm would make the largest head.



In this picture I am using the small 1 mm rivet head die.


Sometimes, the 1 mm wire fits a bit tightly in the die. Then I draw the wire down to 0.90 mm and that works just fine. The same goes for the 1.5 mm wire, especially if commercially made wire is purchased.


Also, the wire should be fully annealed, although I have used hard wire without any problems.


This rivet will make a tiny head when the 1 mm height gauge is used.



These rivets are perfect when one wants to rivet two pieces together where the rivet must not be easily visible – in a situation where the rivet will be peened over and then flush filed to the surface, for instance.

 

I use a 60 gram hammer that has polished faces on both ends.


The smaller end is for smaller size rivets.



The rivet maker comes with four dies that have been hardened to about HRC 55–66 , which is harder than the average hammer face.




On the left is the die for the thick top rivet and on the right is the straight wire die.



As with any new tool, the forming of a rivet head will need a bit of practice to achieve consistent results.


Once the wire has been cut to the correct height, forming the head starts.


Here I have deliberately hit the tip skew, which happens most of the time.



No problem, though.



The solution is to tilt your hammer in the opposite direction and 'spread' the rivet head toward the center.



The hammer taps are spread around the outer edges of the wire, all the while turning the center holder around.



So, one tap, turn a bit, then another tap, then turn a bit and another tap and so on until the head forms a nice 'dome'



Here I have lifted the rivet up for better visibility.



The rivet forming is coming along nicely.



By turning the center holder around whilst I am tapping at about 45°, I can form the rivet head into a neat cone.



A final tap on the top gives the rivet head the shape shown in the picture.



Then I place the forming die into the ejector hole and tap it with the hollow ejector punch.



Here is a nicely formed rivet.



The rivet tool can make 1 mm and 1.5 mm rivets.



And here are some sample rivets that were formed using the height gauge at 1 mm.



Because there was much less metal at the start (1 mm) the heads are much smaller and discreet.

Forming the thick top rivets.


The thick top rivets have heavier heads and therefore need more metal to start with.


To achieve a start with more metal, the metal at one end is melted.


And the melting has to be of a consistent size and amount.


This is where the charcoal block comes into play.


I drill a hole in the block the depth of the entire drill shaft, which is about 10 mm, in most cases.



Then I use the height gauge to determine the size of the melted ball I want.



The longer the wire, the bigger the ball.



Here the wire sticks out 1.6 mm above the surface of the charcoal, because the middle section of the height gauge is also 1.6 mm thick.



Always use flux.


One thing with using a carbon block is that when the flame starts melting the silver, the charcoal produces a reducing atmosphere ( less oxygen) and so makes for nice clean fused balls.


(excess oxygen causes porosity)


Also, one can use any charcoal, like the stuff one uses for a barbecue, for instance.



Just file a flat area, drill a hole and insert the wire, cut to length and you're good to go.



I use a strong hot flame, but not with too much oxygen.


Note: After ten or so of rivets being made, the charcoal becomes a bit ragged around the edges.



The the surface is filed down with a rough file and the hole is then drilled down again to the correct depth.



Here is a close up of the ball melted down to the surface of the charcoal.



The rivet has been removed and is still hot.



Because the height gauge makes the tops all equal in length, when they are melted into a ball, the average size remains consistent, which is important for rivets in general.



The rivet forming die is placed in the center holder.



The fused ball must fit snugly into it.

T

The ball is hammered flat into the die.



After being hammered flat, the die is inserted into the ejector hole and tapped with the ejector punch.



Here are three rivets I made for this tutorial.



There are three cup shaped holders and on flat punch that are used to make and peen decorative rivets.



For this demonstration, I will be using the middle sized cup holder.



The ball size of the rivet must be all about the same size.


This is achieved in the same manner as the big top rivets are made.


First a hole is drilled into the charcoal and then the top part is made into a 'cup ' as is shown in the picture.



In this case I am using a 1 mm drill and a 2.5 mm ball frazer to make the cup.



Now I use the height gauge and trim the wire off at the height that will make the ball size that I want.



The maximum is 4 mm high, which makes a ball of about 2.5 mm in diameter, using 1 mm wire.



The higher the wire, the bigger the molten ball will be.


I flux the wire before I melt it.


Again as in Image No. 21, I use a strong reducing flame to melt the wire.



The idea is to melt the wire so the ball settles into the cup, thus forming a nice spherical ball.



Because the height of the wire was the same for all three examples, the balls are all approximately the same size.



Three rivets after pickling.



For my demonstration, I am going to join two flat links.



I drill a 1 mm hole through both links



To let the ball fit snugly, I also expand the hole with a 2.5 mm ball frazer.



This allows the ball to fit a little bit below the surface.



On the other link, I also counter sink the 1 mm hole, but not as deep as the front side.



This allows the back of the rivet to flair into the countersink and makes for a very strong joint.



Again, I use the height gauge at the
1 mm height to trim the bottom of the rivet off.



Now the rivet must be peened over.



The ball of the rivet is positioned in the cup holder and then the rivet is peened over.



The cup holder keeps the ball round even though it is being hammered from the back.



Here the back of the rivet is half way to being peened over



The bottom peened over.



And the top has remained nice a spherical.


Here is a video