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View Full Version : Shaping and sawing scales for a full-tang construction.



keith_beef
04-03-04, 05:57 PM
Well, I'm not offering advice, I'm asking for some.

You might have seen the little Pecos Caper that I posted in the Gallery. I made up this blade mainly for two reasons:

1. I badly bodged my attempt at the Felleskap, and no longer had enough black vulanised fibre material to start again, but I had enough to do this smalled knife,

2. Having badly bodged the felleskap, I decided I should practice on a smaller piece of work before trying the felleskap again.

The first job was to roughly cut out two pieces of black vulcanised fibre and key the steel of the tang and the spacer by a quick rub with 80 grit paper. Then glue one of these to the tang, with slow setting Araldite dyed black. When this had set, I drilled through the 6mm holes, effectively using the holes in the tang as a jig for drilling the fibre.

A couple of days later, I glued the fibre on the other side and drilled through again.

So, at this stage I had a tang with slightly oversized spacer on each side of the tang, and the holes drilled.

Next, I got a piece of curly birch out of the store, and marked out the shape of the tang on it. Then, I sawed it into two halves, hoping to "book match" the pattern.

Well, I think that perhaps this isn't a very useful thing to do with curly birch. The pattern changes too quickly through the wood. Unless the cut is perfect first time, and no more thickness needs to be taken off the faces that are newly exposed, the faces don't match at all.

Anyway, I now had two halves, allowing me to turn the block "inside out".

But I hadn't sawn very straight, and I had to use my plane to get the faces flat and even. I rubbed down what had been the outer surfaces of the block, which were to mate against the spacer material glued to the tang, by taping prograssively finer sandpaper to a polished granite slab. Then I used the 80 grit paper to key the surface of the tang and the wood, and I glued on one slab.

After a couple of days, I drilled the 6mm holes through this scale, and then glued on the other. A couple of days later, I did the final drilling all the way through.

At this stage, the slabs were still plainly rectangular...

So, I made sure the cardboard and duct tape "sheath" was in good shape, and I clamped this in the bench vice, and set to cutting the scales to shape by using a coping saw to follow the steel tang as closely as I dared.

Then, I used the plane to shave down the outside curve down to as close as possible. I couldn't do this on the inside curve, but Firewood helped me out with this :D

Then sandpapers and a bit more carving with Firewood to take off the edges, and it was ready to get the 6mm mosaic pins and the 6mm thong ;) hole. I measured the length of the holes, and took off a shade to make sure that the metal wouldn't stand proud of the wood after finally rubbing down or through wear...

I mixed up a little bit of Araldite, stained black again, and used a toothpick to smear a little bit of glue on the inside of the holes, and tried to drive the pins into the holes. They were a tight fit, probably the holes are not quite straight from being drilled in four steps. Driving them in distorted them a little, and maybe I made them a tad too short.

A couple of days wait, again, and it was time for a final (I thought) rub down with sandpaper (taped to the granite slab and wrapped round wine corks and brass rod) before treating with "kitchen worktop oil". This looks to my untrained eye to be little more than a mixture of linseed oil, a little bit of tung oil, and cobalt siccative. But if it's approved for kitchen worktops, then it can't leave much of a toxid residue, and should be pretty water resistant.


Oh, I forgot to mention, I drilled out two 3mm holes at the same time as the 6mm holes, but in the end I filled them with black stained araldite, just to keep moisture out while I'm trying to find something suitable to use as a pin in those.


So, after that lengthy preamble, my question is "did I do things in a sensible order"?

I'm doing another knife, using the same full-tang construction with two slabs and contrasting spacers. This time, though, I'm doing things slightly differently;

1. I'm using white fibre to contrast with dark Leadwood,
2. I'm shaping the wood to more or less the shape of the tang before I saw it in half.

The Leadwood is quite a lot harder than the birch, and very dry and a bit brittle, too. It makes a lot of very fine powder as I saw or rasp it.



KKK.

Kevin
04-03-04, 06:33 PM
Keith...I think you did things :censored: well :) .....and it worked.

This is how I sometimes do it...

If I were using a spacer, I epoxy the spacer to the wood and let it dry.

I then drill the holes in the tang...but to a smaller diameter, because I am going to use a smaller diameter pin to first fix the scales....

I then use the holes in the tang as a guide for the holes in the scales...same small holes.

THEN....I remove the scales from the tang and pin them together with the small pins (so they are flat to flat).....I then file, sand, grit or what ever the front face of the slabs.....and shape them with a bevel (I dont g any further in shaping the handle ..just the front bevel and maybe even the sides up). Done like this , I know the handle slabs will look symetrical as they sit on the ricasso..and I have beveled them towards the ricasso so I dont need to touch in there when they are glued to the tang and scratch the blade later .

Then I epoxy the slabs onto the tang, and ue the small pins to go all the way through as guides and temporarily hold it together)......

IMPORTANT.....I then clamp the handle slabs with a clamp and REMOVE the small pins before they set!!!!! and wait for the epoxy to dry for a day or so.

I now have the slabs fittied in place, , but no pins fitted and two undersized pin holes :)

I then re drill the holes with the same small drill (do this while the slabs are still flat and not shaped so the holes go through straight).....then use the right size drill bit for the pins and drill all the way through...being carful not to push and split the far side!!!......using a drill press.

I cut the pins to just over the length required and slightly bevel/round the pin which is going to be pushed through....this helps it go in easier and helps prevent it spliting the wood on the far side.
I also put some small cuts into the pins to help secure with epoxy.

There are many ways of doing it..but it seems your way worked fine....Taking your time and being patient pays :)

Bazza
04-03-04, 06:59 PM
Keith,
I do it similar to the way Kevin described, after drilling the slabs and shaping the front with the slabs pinned together, I then drill the slabs to the size of the bolt/rivet to be used and countersink. At this stage you want to assemble everthing to make sure it all fits together as it should.
Key the tang and clean with acetone, roughen the spacer if required and clean, then set all the parts out on your bench in the order of fitting. Mix the epoxy together( I use 4 minute for this).
Start with left or right slab as prefered.
Thin coat of epoxy on bolt, bolt into hole in slab.
Thin coat of epoxy on tang, push slab onto tang.
Thin coat of epoxy on opposite side of tang, coat nut or end of rivet, push into other slab. Put slab on tang, tighten with screwdriver, wipe off excess,let dry.

Colin KC
04-03-04, 07:25 PM
Keith,

We could each tell you the way we do it & you would get as many different variations as there are of us!

We can all agree, I'm sure that you:

glue the spacers to the flattened slabs.

profile the blade end of the slabs TOGETHER

carefully drill the holes making sure they're straight

I can only add, that its best to slide the spacers onto the slabs (avoids any bubbles, which will magicall appear when you sand to shape:rolleyes: ) clamp the spacers on the slabs (not too tight)

Drill some keying holes in the spacers (within the boundary marks of the tang;)) this also helps avoid any unpleasant bubbles & dont clamp too tight! (this will thin the epoxy down to virtually nothing, which will reduce the efficacy of it)

Martyn
04-03-04, 07:29 PM
( I use 4 minute for this).
Start with left or right slab as prefered.
Thin coat of epoxy on bolt, bolt into hole in slab.
Thin coat of epoxy on tang, push slab onto tang.
Thin coat of epoxy on opposite side of tang, coat nut or end of rivet, push into other slab. Put slab on tang, tighten with screwdriver, wipe off excess,let dry.


Wow, all that lot done with 4 minute epoxy? You ever thought of trying out for the Ferrari pit team? :D

Seriously though - it seems a bit "sudden death" to do it that quick and to assemble all of it in one go. I prefer a "much" more sedate approach. I've got the 24hour epoxy in for this job (I think it's a tad stronger too). I havent made many, but my method is pretty much identical to kevins - I guess that from a few years hanging out on CKD. :)

I agree, spacers onto the wood first, not onto the steel, then shape the front bevels of the wood before they go onto the knife. Kevs method of using a small pin first, seems lengthy, but it guarantees that the front ends of the slabs line up after they've been fitted to the steel.

Damn, gotta finish up some of the dozen or so projects sitting on my "to-do" shelf. :rolleyes: I havent finished one up in yonks.

Colin KC
04-03-04, 07:33 PM
I guess that from a few years hanging out on CKD. :)


Uhuh :hump: ;)

Colin KC
04-03-04, 07:35 PM
gotta finish up some of the dozen or so projects sitting on my "to-do" shelf.


Uhuh :hump: ;)

Bazza
05-03-04, 06:27 PM
Martyn,
if you have fitted it all together first to make sure there are no problems and lined up your work pieces in order, 4 minutes is fine (sometimes I use 24 hour anyway). It actually takes longer typing a description than doing it.
Bazza

stonehard
11-03-04, 09:34 AM
I needed to drill the bone scales for my KITH kit folder. Now as you know marking the dead centre of a screw hole on a piece of Stag or bone is hard due to the uneven surface which means measuring is out. So after shaping the scales to fit the liners which were attached with heavey duty double sided tape or hot glue

I lightly spot marked through the already drilled and threaded liners with a small drill to mark the flat side of the scales ( be carfull to use a small drill if the liners are threaded as you will drill the threads away.)
I then went to my pillar drill and after removing the drill head turned the table 180 degrees so the flat surface is facing down. some drill tables will pivot 180/360 degrees.
I then placed the flat of the scale upwards on the table and drilled accurately through the scales with the same small drill.
this gave me perfect positioning and 90 degree angles for all the holes. I then reversed the table back and drilled out the holes with a shoulder drill for the torx screws. This of course would work with fixed blade full tangs as well.

Trond
11-03-04, 11:01 AM
I have this to say about 4 minutes epoxy:
i would love to use it but:
Like Martyn i dont think it is as strong as 24 hours.
It comes loose when the materials heats up during the making prosess caused by heath. When i grind (yes i grind on a grindingmachine :rolleyes: ) the handle to shape the metal in the tang and the pins gets hot, and melts the glue :(

ugug
11-03-04, 04:20 PM
..also you always get some :censored: calling thirty eight seconds in to the process and refusing to get off the phone for three minutes.. :banghead:

slow is good :D

Bazza
11-03-04, 05:02 PM
Stonehard,
neat trick, I must give it a try. If the table is flat underneath, can you drill through the hole in the centre?
Bazza

stonehard
11-03-04, 11:42 PM
Stonehard,
neat trick, I must give it a try. If the table is flat underneath, can you drill through the hole in the centre?
Bazza

Thats the idea, flip the table and drill down through the centre. If you have a flat underside to your base no need to flip but I think that would be rare as they are almost allways cast from iron. the table will be sqyuare to the drill bit thus the holes are 90 degrees and in the right place.


I did think about making a clamp as well but most scales are soft so you can hold them flat with your suitably gloved hand.
I dont use gloves but someone is bound to get a spinner and sue me for loss of a finger or three.