How to Make : Tanegashima Pan Cover Hollow Pin

[watsonmil]

Over the years I have carried out innumerable antique firearm restorations. Often one of the most challenging can be repairing or replacing missing parts on the Tanegashima. Since I haven't bored you all for awhile, ... I thought I might ( although a few may find this helpful ). Quite often a Tanegashima will be absolutely complete but for one little item. The brass mekugi hibuta ana ( hollow pin that fastens the pan cover ( hibuta ) to the pan tray ( hizara ) will have gone missing and be replaced with a solid brass pin or as I once seen a cotter key !

Now then this little hollow pin looks simple but is a puzzle to make . Well lets make one :

 

1. Gather the necessary tools, ... a small hammer, a good pair of scissors, a hack saw, a center punch, two pair of pliers, fine emery paper ( crocus cloth ), a 9/64 bit ( metric number 68 ), a 7/64 bit ( metric number 75 ) and of course an electric drill and access to a vise and it helps to have a small band sander.

 

2. Material required, ... a round headed BRASS woodscrew or machine screw ( not brass plated steel ) one inch long ( 25 mm ) .... bloody metric ! .... small amount of sheet brass about 26 -24 gauge ( wall thickness of a .22 shell casing ), ... a little solder, flux, propane torch.

 

Ok, ... here we go: Cut your sheet brass 7/16 inch wide ( 11 mm ) ... slightly wider will not hurt .... by 1 inch long ( 25 mm ). Now take the 7/64 bit the plain end and lay it along the middle of the piece of sheet brass. Using a pair of pliers squeeze the sheet brass around the drill bit working slowly until you have formed a small brass tube. If you have a little excess brass simply tuck it under, ... but if you've measured exactly the two sides should just nicely butt up to one another.

 

Next take your round headed BRASS wood screw and tighten it into the vise head pointing up. Now if it is a slotted screw take your small hammer and carefully peen with the hammer all around and on top until you've completely closed the slot ( do not flatten the top of the screw too much ) Once you are satisfied, ... take your center punch and mark the dead center of the top of the screw ( to accept your drill bit which comes next ). Using the 7/64 bit drill a hole straight down from the top until you are nicely thru the head part of the screw ( make sure you go deep enough however ). Now using the hole you have just drilled take the 9/64 bit and drill to make the hole larger and just as deep.

 

Loosen the vise and raise the screw just enough that you can lay your hacksaw blade flat against the vise. Tighten the vise and cut the head from the rest of the screw ( be careful not to lose the head ).

 

Now clean the hole up a bit using emery paper and/or your 9/64 bit. You should now be able to insert your little brass tube into the head until it protrudes perhaps a mm or two thru the top. It will be a snug fit. Now apply a tiny bit of flux on the underside around where the tube and head meet. Heat with your propane torch and apply a miniscule amount of solder. Allow to cool, ... then insert your 7/16 bit plain end up until it comes even with the top of your screw head NOT the top of that mm or two tube above the head ! Insert in the vise with the head resting on top of the vise. Now take your center punch and slightly spread the mm or two of tube. You can now peen with your hammer this mm or two flat around the top of your head. If done right it will hardly be noticeable and most will be removed when touched up on the belt sander or grinding wheel.

 

Since about 90 % original pins have a head that is exactly 1/4 inch ( 6.35 mm ) you can now use your belt sander or grinding wheel to round the sides of the screw head to this diameter. Also I have noted upon examining dozens of tanegashima that the hole thru the pan cover and pan tray are usually 9/64 inch ( 3.57 mm ), ... so one size fits all .... BUT NOT QUITE !! There are a few whose pin hole is larger and in these instances you can follow the same directions that I have given except that you will have to adjust the bit diameter to suit your gun and also the amount of sheet brass to make your hollow pin shaft.

 

Now after inserting your new pin, ... mark off where it protrudes thru the bottom of the pan cover, take out the pin .... and drill a 1/16 inch hole ( Metric bit number 52 I think ). This is for a tiny piece of wire to hold the pin from being lost again. Below this small hole you can use your hacksaw to cut off any extra pin length not needed. Clean up your pin using fine emery cloth ( crocus cloth is best ) and patinate to desired colour.

 

I have assembled a few photographs as a picture is worth a thousand words. As I find the time, I can if there is interest go into other areas of making missing or broken parts. Its up to the members to decide.

 

... Ron Watson

[b.hennick]

Wonderful post Ron!

Athough I will not be making this object the process is very interesting. I remember doing some work for a person told me "I have only one tool." Of course I asked him which one? His reply was "a cheque (check) book" Canadian spelling first. This is a case where I would use his tool.

[Brian]

Wow.....my mind tells me there has to be an easier way. But nice write up Ron.

The end result is very convincing. I'm sooo glad mine came with an original pin. I know they can be easily turned on a lathe, but the originals are definitely rolled from sheet, so it wouldn't be authentic enough for me.

Thanks for sharing, keep them coming!

 

Brian

[watsonmil]

Dear Brian,

Yes, ... thank you for noticing that originals are made from rolled brass . If at all possible I work with hand tools or at least as far as I can when re-creating parts. You can buy different sizes of brass tubing from " Model Shops ", ... but the finished product does not look hand made and therefore not as the original. It is important when restoring to use the same type tools ( as much as reasonable ) that the original maker used, as it gives one an understanding of how things were done. Much like when you look at Ford Hallam's work, ... pretty much the tools and techniques that the old tsuba makers used are employed in his work. In this case to be truly honest, ... I should have hammered out the head section rather than use a brass screw, ... but this pin is not terribly valuable ( worth the extra time ) nor is my shortcut ever going to be noticed. Restoration can sometimes be a balancing act .

... Ron Watson

[Bugyotsuji]

Full of admiration. I know from experience how satisfying it is to create such things by hand. To write it up must have been another labor/labour of love, though.

 

Such a small thing, but so important in my mind too. I remember buying my second Tanegashima, a lovely 6 Monme Hino gun, and feeling disappointed that the pan hinge-pin looked wrong. Almost as an afterthought I asked the Banto of the shop about it. He pulled an old one out of a different HInawa Ju he had for sale and stuck it in mine, perhaps hoping that the next customer would not mind. Regardless of his motivation, I felt such relief that a seemingly impossible hurdle had just been removed so easily. Only for the purist!

[Jean]

Ron,

 

You have also all my admiration.

[estcrh]

Ron, many thanks, I need one of these!!