Bell cap how to - Printable Version

Bell cap how to - Printable Version

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Bell cap how to - jvrjenivs - 11-20-2009

Hi All,

As promised is another topic (See here) a tutorial about the making and use of bell caps to secure rivets.

First start with taking a better look at an original. You see here one that is attached to a pendant of horsegear. I personally would date it as first century AD. Anyway, what is interesting is that there is still a piece of " leather" hold between the pendant and the bellcap. It is in the collection of Brian Stobbs and I had the change to see it up close last year. Big Grin

Brian has fixed the 'leather' remains with some glue so the wouldn't loose.

[Image: originalStobbsCollection.jpg]

Okay, what I'll show here is the type of bellcap I most use. It is a 6mm wide cap used to secure 2mm rivets. (I use mainly 2mm shafted rivets for beltplates etc.) Going to make some more pictures now. Next post will be about the tools you need to buy and to make.

Re: Bell cap how to - jvrjenivs - 11-20-2009

Okay, now to discuss the tools.

You need to have at least a hammer and some kind of iron block (or anything else that can be a hammering support like an anvil). I'll not discuss proper hammer use in here, but if you don't have got proper hammer handling I would suggest you look at some better fora for support.

[Image: IMG_3905.jpg]

Next to that basic tools I bought the following:
-center punch (second to the right)
-.5 mm punch (most right tool)

No, I use a round punch for making the doome. This can be used, but these sets tent to be expensive. So a rounded iron self made punch will do also. (most left in picture). This tool you should be able to make yourself out of a 6 mm iron rod and harden.

Next to that you see an 8 mm iron rod. This is used to punch the bell caps out of the sheet. This one I should replace with a better hardened tool, eventually.

[Image: IMG_3906.jpg]

Now the 2 more interesting tools you've to make yourselves. First the top one. Actually Brian did this tool for me, so I know not all details exactly. I'm sure he will join in when you need more about this one. This one is made from a brass bar 15 mm wide, 6mm thick, but almost all bars of that thickness will do. Just what you can find as scrap will do, as long as it's not thinner and at least 15 x 15 mm. In that you've to drill a hole and insert into there a rivet with a 5mm head. (you've to check the shaft diameter to predict the drill bit. Set the rivet in the hole and just gently hammer a time on top of it to just flat it a bit, so you know the center of the rivet. Now, use a 2mm drill to make another hole through the rivet. (Use a drill standart for this as it should be a perfect drill!) Now you first bit is ready.

The next tool I just made from a 6mm nut, but again every piece of metall of proped size will do. First you have to drill a 6mm hole through it. (or as I did remove the screw by drilling). Now turn the tool upside down and use a 8mm drill to drill 2/3rd of the thickness (but make sure the 6mm part is thick enough, as force will be applied onto that rim!). So from top to bottom you will first have a 6mm hole which will eventually widen to 8mm. My screw is 5mm thick and that is too thin, so I always have to place that one onto another tool, so the hole is deeper.

So, now we've discussed the tools we can move on to the real work.

Re: Bell cap how to - jvrjenivs - 11-20-2009

Okay, lets start making them. First I've to say it is rather hard working on them and taking pictures at the same time, so no pictures of me actually making them, but I tried to make pictures where you can clearly see the stage of production and what is to be done. If something isn't clear, don't hesitate to ask, and I'll try to make it more clear.

For those I mainly use some scrap .5mm brass sheet I get from cutting brass shield edgings. So you don't wast any brass. .6mm should be better though. .5 is really the minimum you need for making bell caps. So we start with a scrap piece of brass sheet and make a doom into it, using the punch. I either do this directly in the 'nut'-tool (as shown here) or on my dooming block.

[Image: IMG_3907.jpg]

Next you take the 8mm rod and place it onto the doom, which is in the tool now and tap a couple of time on it, so you punch out a nice round bell cap. At this stage you should be able to see the ring of this tapping on the sheet, but not try to punch it our already, that's done next, with the round punch again.

[Image: IMG_3909.jpg]

Re: Bell cap how to - jvrjenivs - 11-20-2009

Now using the rounded punch again, you take punch out the doom. (I did this one maybe a bit to fast and it was the only I did now, so it isn't so perfect round. But doing a lot of them will get your feeling of the hammer and material better, which nicer results). Getting them nice round needs some practise.

[Image: IMG_3910.jpg]

So we end up with a doomed round piece of brass:

[Image: IMG_3912.jpg]

Re: Bell cap how to - jvrjenivs - 11-20-2009

Now, with gentle tapping on top of the bell cap we make it a bit flat, so we can see where the middle is. Next we use the other tool we made and place the flattened bell cap on it. Now, using the centerpunch and a single tap we make a little dent in the metal.

[Image: IMG_3913.jpg]

Now, using the .5mm punch we tap through the bell cap to make the final hole. With some practise you'll now when you hitting the 2mm and you are ready tapping.

[Image: IMG_3916.jpg]

Re: Bell cap how to - jvrjenivs - 11-20-2009

Now, when you take the punch out of the tool, it could be the case that the bellcaps still is on the punch. Take a pair of tongs and take it of.

[Image: IMG_3917.jpg]

Now, there could be still a little piece attached to it (which is the result for the punching out the hole). This you have to remove also. I was unable to take a clear picture of that, but you'll find it out yourself soon enough.

Now, your bellcap is ready:

[Image: IMG_3920.jpg]

So, I hope everything is clear. Make sure that when using these to rivet you have to be more gently then with normal washers. Good luck all!
And of course again I would like to thank Brian Stobbs for learning me all this and the use of a picture of one original in his collection. But for now, just practise, and when anything isn't clear, let me know! Both Brian and I are happy to help you with this.

Re: Bell cap how to - sulla felix - 11-20-2009

Brilliant stuff!

Thanks Big Grin

Re: Bell cap how to - M. Demetrius - 11-20-2009

Very well done, and clearly explained. Good job!

Re: Bell cap how to - L_CORNELIUS_CETHEGUS - 11-20-2009

Thanks! These will be on my next balteus for sure!

Re: Bell cap how to - jvrjenivs - 11-20-2009

And to make it complete, here a pic of one of my recent belts where they're used.

[Image: DSC07193.jpg]

Re: Bell cap how to - Gaius Julius Caesar - 11-20-2009

Good tutorial Jurjen. You did Brian proud there! I've yet to start mine due to space and time conflicts.
But Brian convinced my of their use a couple of years back. A sound principle and superior to flat washers cut from sheet!

Re: Bell cap how to - PhilusEstilius - 11-20-2009

Jurjen That is a very good tutorial and I'm sure that when re-enactors begin to make and use these things they will find just how interesting they are.
Infact it should be mentioned that in using bellcaps the riveting poundage is greatly reduced as opposed to using a flat washer, infact just on estimation I would say that it is reduced to only 10% of that needed for a washer.
The secret is that when punching the hole in the dome it creates a countersink and it only needs a few gentle taps to lock the rivet home, infact whoever created these things in the first place had to be a craftsman who understood the art of riveting.

Re: Bell cap how to - Doc - 11-21-2009

Excellent tutorial. That is an interesting little gadget there.

If a belt plate needs to be secured to a belt, do you put the rivet throught the belt plate, then the leather, and finally through the bell cap where the end of the rivet sticking through the cap is hit with a hammer and pressed onto the top of the bell cap?

Re: Bell cap how to - jvrjenivs - 11-21-2009

Quote:Excellent tutorial. That is an interesting little gadget there.

If a belt plate needs to be secured to a belt, do you put the rivet throught the belt plate, then the leather, and finally through the bell cap where the end of the rivet sticking through the cap is hit with a hammer and pressed onto the top of the bell cap?

Yes, you're right. Only I wouldn't say 'on top of the bell cap'. I would lather say countersunk into the bellcap. If done right, the rivetshaft shouldn't stick out of the bellcap, but just form a doom together with it.

Re: Bell cap how to - PhilusEstilius - 11-21-2009

I'm not wanting to steal the show but it's correct what Jurjen has mentioned if done very tidy the rivet shank should just make a nice curve with the dome of the cap for infact a bellcap is simply a created countersink.
Infact what one can do is use a needle file to take away any burrs or as is known in the metalwork trade remove the rag, this way a belt does not catch any armour and can even be worn against a tunic without snagging.