Get out of jail card

It is Sunday, (or after trading hours), or simply live too far from your normal woodworking supplies shop, and your drum sander has run out of abrasive.

What do you do?

I decided to find out if there was an alternative, if only temporary to get you out of trouble so you can finish the job you are doing.

Headed down to Masters to see what was on offer.  Seriously….very little.  Certainly no cloth backed sandpaper in a roll or of any length.  About the only stuff I could find was a very weak paper backed painter’s sandpaper.  No idea how it’d survive – you just touch it and the abrasive is flaking off the backing.

Went to take a length anyway, and discovered that even worse, it is perforated every metre (for easy tear-off – the last thing you want for a machine sander!)  But there was nothing else, so it was either this to get out of jail, or nothing.  It wasn’t the right width either, so it was going to be an interesting attempt.

First, I took some packing tape, and ran a length down the entire back of the 2m long strip I bought.  Oh, and the strip cost $4 ($2/m), compared to something like $18 for the real deal.  (Remembering this is a temporary fix, not a long term viable alternative).

With a bit of guesswork, I trimmed the end to an angle, then with a bit of adjustment got it so each loop butted up against the previous, and got to the opposite end of the drum.  That was a lot easier, as the end was simply trimmed to be parallel to the edge of the drum, and secured with the second clip.

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Kind of looks the part doesn’t it!  Also proves that you can use other widths of sandpaper – you are not restricted to just using a 75mm wide roll (think that is what the standard width is).

A quick test – turn on and off (while standing clear) – seems to work – it didn’t fly to shreds instantly.

Next test – sand something!

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Took a scrap of timber, and ran that through.  It survived as well, even multiple passes.  You can see a gap at the right hand side- I hadn’t gotten sufficient tension in the roll, so after this pass I readjusted the paper to get it tight on the drum again.

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After a few passes, the wear is a lot more evident on this sandpaper than is on the garnet cloth-backed sandpaper.  However, it was working.

So let’s do it for real.  Got the piece of walnut that I needed to sand, and ran it through again, and again to flatten it off.  I did go with a slower feed speed and less height change between passes to give the paper the best chance for survival.  Even so, near the end of the job the drum was bogging down a bit as the paper was loosing its ability to cut.  But I got the piece flattened (over a dozen passes)

Turned it over to dress the rear side a bit, and managed to get about three passes in before the paper exploded off the roll.

It wasn’t dangerous – the paper was flapping a lot on the drum, but there was no issue in turning the machine off.  There were bits of sandpaper everywhere (about 1″ square) – when this let go, it really let go!  Surprisingly, the perforated area halfway along had survived (although had started to tear when the length failed).

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The proof of concept was achieved however – I have a nicely sanded piece of walnut – so this indeed “get me out of jail”  It isn’t the most economic – an $18 length will last and last (until you burn it or do something silly, or wear it out), but for a one-off when the shops are shut, this worked.

Be your own judge whether you choose to ever do this for yourself or not.  I am satisfied that there was no real risk (and I stood aside even so).  If I have to do it again, I may try gorilla tape next time – something a bit stronger than a cellotape-type packing tape which may increase the time the temporary fix can survive.

Completing timber dressing

The boards have been resawn on the bandsaw, and had a side and edge dressed on the jointer.  Next step is the thicknesser.

15" Thicknesser

I have a 15″ thicknesser, with a fixed head and the table rises and falls.  I prefer this style of thicknesser, but it isn’t everyone’s cup of tea.

The other version has a fixed table, so any additional infeed and outfeed support can remain at the same height, and the motor and blades rise and fall.  Winding the height down isn’t a problem – gravity and all that, but increasing the height is a lot more work, especially with the weight of a decently-powered induction motor overhead as well.

On the other hand, my thicknesser has a motor in the cabinet, and rise and fall is only the weight of the table – very smooth, very easy.  Added bonus, as the head doesn’t move, I have my drum sander located on top,  and a very functional arrangement it is, especially as the thicknesser and the drum sander both have the same requirement for infeed and outfeed.

Dressing boards

With the side dressed on the jointer face-down, the boards are fed through.  There is no point rushing the process – a little taken off each pass will still result in a finished product very quickly.

If I had a spiral head, things may be a little different, but I still have a thicknesser head with straight blades, so loading the machine and chipping away needs a little more finessing.

This doesn’t refer to the ‘spiral’ heads that have a bunch of the small square cutters arranged in a spiral around the head, but are still presented to the timber straight on.  This means the loads on the blades and machine are much less, but they are still chipping at the surface.

Instead, there are spiral heads where the small blades each present to the surface at an angle, producing a slicing motion.  This gives the best finish, combined with the benefit of much lower loads on the tool, and excellent waste clearance.

Completed boards

The boards, now complete (and you can see the bookmatching, if I intended to use the timber for that).

In this case, I now have a dressed side, the other side also dressed and parallel to the first side (and the boards are a uniform 10mm thick).

One edge is also flat, and at 90 degrees to both sides.  This side will be very relevant for the next step – the tablesaw.

How a thickness planer works.

From Wikipedia - a diagram of thicknesser operation

An illustration of the operation of a jointer ...

From Wikipedia - compare the above operation to this one which is how a jointer works.

Picking up a slab

In many sheds (and parties, and sports clubs) down under, that’d raise connotations of an end of the productive side of the day, and the cracking of a few favourite beverages is about to commence.  But for woodworkers, there is also the possibility that it means just that – the acquisition of a large flat slice of timber, usually cut by someone else who has more specialised toys than in the average shed.

However, if you own (or are considering) the Torque Workcentre, it is not out of reach, as the slabbing attachment gives the typical workshop the ability to claim very useable timbers from the very trees in which it grows.

The attachment has 2 main parts – two clamps that attach to the main arm on the TWC, and securely clamp a chainsaw between them.  About 4″ of the chainsaw bar length is lost in this, so a 16″ chainsaw can slab a maximum width of 12″.  The bigger the chainsaw, the more powerful the motor, the larger the slab you can manage.

There is a block on either side of the bar (narrower than the width of the bar, so as not to touch the chainsaw teeth) that hold the chainsaw firm, and with one at either end of the bar, it is locked in tight.

The position is probably different from chainsaw to chainsaw, but a hole through to, or scalloped out area near the chainsaw would be useful so blade adjustments can be done without the need to remove the chainsaw from the jig.

I’d also like to see some form of oil reservoir mounted above the chain with a controllable feed rate, as the normal chain lubrication method being gravity fed is rather ineffective with the chainsaw perpetually on its side.  However, these are all refinements to the basic operation.

I started with a lump of camphor laurel (yes, oh Roving Reporter, THE lump of CL – you’ll have to find an alternate seat!) that I picked up for $10 a couple of years ago, and secured it to the TWC.  Although this piece is short enough to pass through a resawing operation on the bandsaw, it works well as a test piece here.  With the chainsaw bar levelled out, and the depth of cut set, I was ready for a first pass.

The first cut was set very shallow – I only wanted to take off enough to flat-spot the log, so it would sit more securely on the workbench for further slices.

As the chainsaw bit in, the unmistakable aroma of camphor wafted through the shed, undiminished by the continuous air filtration of the Microclene unit, or even the head protection afforded by the Purelite Respirator (I geared up a bit for this) – I’d have to have used a carbon filter to extract that, but it isn’t unpleasant (although my wife strongly disagreed when she made a surprise visit, committing the cardinal sin of interrupting shed time 😦 😉 )  Even a couple of hours later when I walked past the outside of the shed, the smell was still very much in evidence!

With the first cut complete, the log was flipped over for the first slab to be cut.

One of the problems I always have, is getting timber that is thick enough when I go shopping – like purchasing steak from the supermarket, they are sold so measly thin, on the (probably correct) assumption that people will buy more quantity, rather than quality (3 thin steaks sells better than 2 thick ones).  This isn’t an issue when you do it yourself, and in the case of slabbing a trunk, you can cut the slab as thick as you like.  And you can also choose whether you want regularly sawn timber, or quarter sawn.

Not an option you normally get from a box-hardware store.  For the same reason – a quarter sawn log is more expensive (more timber is wasted) and the average shopper doesn’t distinguish, other than on the price.

There are plenty of ripples across the surface from the cut, but a few quick passes through the drum sander got rid of them without a problem (I used the drum sander to avoid the snipe from the thicknesser on a short board).

Finally, it was off to the new workbench, and firing up of the Festool ETS 150/5 (random orbital sander)

Hard to see here, but a quick rub down with a wood oil (the ol’ Triton oil in this case) really picked out the details.  I didn’t actually need to oil it yet, other than my own curiosity – the board will head over to the tablesaw to cut it to size for the next project, and get whatever finish is applied to that, but I just wanted to really see how the details responded, especially the spalting, to a bit of oil.

Now That’s a Knife

It’s only been 4 months since I got this set of steak knives from Professional Woodworker Supplies.  That is a pretty quick turnaround time for me these days!  Everything hasn’t gone to plan though, as I will elaborate, but I got close to achieving a good result.  I don’t like accepting a compromise – it may be that others wouldn’t notice anything wrong, but I would every time I use one of these.  However, I’m getting ahead of myself.

Knife blanks

These four knives are begging for some stunning handles (the timber on either side are known as “scales”), and so the timber of choice is African Rosewood.  I recently bought a couple of lengths during the recent April WoodFest with the vague idea of making a box, but it jumped out at me when I was looking for what to make the knives from.  The timber is around 19mm thick, so a bit over double the thickness required for each side of the knife.  So resawing was the order of the day.

Resawing the African Rosewood

I changed the blade down to a 5/8″ blade on the Carbatec bandsaw, then racked up the tension.  With the MagSwitch fence in place (single roller), the blade sliced the timber cleanly in two.  I am so loving having the bandsaw tensioning handle below the upper wheel.  The benefits of a larger bandsaw.

Single Roller MagFence making the job easy

Can’t beat those MagFences either for resawing. Love how easy, and accurate it makes the task.

Passes through the Drum Sander for accurate dimensioning

From the bandsaw, the next step is to run it through the drum sander.  This may not be everyone’s first choice – for one you have to have a drum sander to be able to use it.  I’ve become a big fan, especially for situations like this.  These are pieces of timber way too short to ever consider running through a thicknesser, so you’d have to resort to a ROS, hand plane or similar.  Me, I like the electron-murdering whirling abrasive wheel! With careful passes, I was able to get the board down to within 0.1mm of the required thickness.

Jig to accurately cut the handles

Next job was to shape the scales.  The only important side initially is the edge that butts up against the bolster.  To save on timber (a big mistake – not how I chose to do it, but any attempt to scrimp on timber inevitably leads to undesirable results, and more timber wastage. I know this, and still find myself doing it), I cut the timber close to dimension, and drilled holes using an MDF template I made of the scale from the knife tang. I used a couple of lengths of brass rod to replicate the rivets to position each scale to be cut precisely.

Thinning down the pins

For the two pins, I needed them a little thinner than the rivets would be, so I could get the scales off the jig.  To take off a small, controlled amount, mounting the pin in the drill, then running it on the sandpaper provided a precise size decrease.

Ready to cut the handle end

In hindsight, doing it this way was a mistake. Drilling the holes for the rivets needed to be done after the first scale was glued to the tang.

Knife handles roughed out

The scales, ready to be glued on.  Rather than gluing both sides at once, the plan was to do one side only, then use a pattern copying bit to get the scale to accurately match the tang.

Gluing the first handle side on

Two part epoxy resin (Araldite) being the glue of choice.

Clamped up

There is plenty of overhang which is a good thing, but this is where two mistakes compounded.  The trying to be too thrifty which resulted in the scale slipping in a couple of cases enough that the tang wasn’t properly covered, and when the glue had set, not trimming off the excess resulted in a couple of chipouts on the router table that destroyed the handle.  The router bit here is a straight bit with copying bearing.  Straight after this, I was down at Carbatec and picked up a solid carbide spiral router bit with double bearing – the spiral has a shearing/slicing action rather than a chipping action for the next time I attempt to make more handles.

Shaping the blank to the handle

Did have a couple of successes, the bearing running on the tang so the scale gets cut accurately to match.

As good as it got

The results were looking good, and the few refinements to my technique should prove very successful.  For the handles here, I took the photos, then took a chisel and snapped the scales off. Oh well, I’d rather it right than compromise.

Developing the Dust System

Another small development – from the overhead system from the bandsaw, it now leads across the shed to above the thicknesser and drum sander.  This drops down, picking up the outlets from these two machines before heading off to the dust extractor.

Picking up the dust generators

The diagonal clear pipe is from the overhead trunking. The drum sander feeds into the top of the Y section.  The trunking then leads to a second Y section which connects to the thicknesser.  Blast gates on each inlet obviously.

It has proved significantly harder to retrofit a new trunking system into an already occupied (crowded) shed.  It means the system is perhaps not as optimised as it could be.  Even though there seemed an excellent selection of parts in the trunking kit, more is needed.  Some longer runs use up joiners that would otherwise be needed for the components.  But I can’t knock having a system where everything actually joins together without duct tape fixes.

A roll of glossy, grey duct tape.

Rabbit Run Fixes

I still find the Rockler blast gate mounts superb, and provides a very secure system.

Rotabrade on New Inventors

Saw an interesting product on “The New Inventors” tonight on ABC – the Rotabrade – a drum sander that attaches to your angle grinder.

Rotabrade

Rotabrade

After seeing it in action, it looked like it had a decent amount of control (and compared to the Arbortech, control of some high speed sandpaper is NOT an issue, despite what the judges thought!)

Not sure when they will be on the market – won’t be long I imagine after appearing on the ABC – it is bloody hard even getting on there! Cost of the unit is said to be around $15.

Yay for a new season of “The New Inventors”

Yay for Aussie inventors

Yay for Australian manufacturing

SSYTC007 Preparing a Burl

Taking a slice of burl, and getting the surface flat has traditionally meant I have broken out the belt sander which (unless it is a particular shade of green) is NOT a precision machine.  Some will use handtools – planes, scrapers etc to get the surface flat, but circumstances (and a complete lack of time) means I tend to select powered (electron murdering) machines, and the drum sander is particularly suited to the task.

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