Wednesday, November 04, 2009

Connecting to SCOM from the Powershell ISE

Temporary interlude, figuring out how to get some numbers from our IT environment to create some models for complexity in our technology environment. I thought System Center Operations Manager should be useful here but running powershell from the SCOM shell isn't that clever. It'd be much nicer in a decent editor... but how? I couldn't find this anywhere else on the net... so here's how I managed to get SCOM (R2) accessible from the Powershell ISE...

import-module "C:\Program Files\System Center Operations Manager 2007\Microsoft.EnterpriseManagement.OperationsManager.ClientShell.dll"

&"C:\Program Files\System Center Operations Manager 2007\Microsoft.EnterpriseManagement.OperationsManager.ClientShell.Functions.ps1"

Start-OperationsManagerClientShell -ManagementServerName: somemachinename -PersistConnection: $true -Interactive: $True

Wednesday, March 18, 2009

S&G Night Heron – Fibreglassing the Outside

Quick notes from here on as the exterior was considerably easier than the interior.

I bias cut the fibrglass for the exterior to get it to drape better. The epoxy application was much simpler than inside although I did find a few areas that ended up a bit on the dry side. Main reason for this was I ended up working into the evenings and the lighting was awful. This also resulted in a couple of unnecessary floating bubbles and drips – but all easily fixed. So much easier after having done the interior first.

One tip (I think) was to fibreglass across the sheer line; that is, when I fibreglassed the deck, I went to about an inch beyond the deck-hull join, and likewise when I fibreglassed the hull, so that the join between deck and hull was secured with interior tape and a doubling of the exterior glass.

I doubled the glass on the exterior hull from the sheer line to the keel so that under my body I ended up with 4 layers of 200g (6oz) fibreglass.

Having read about the difficulties of making a lightweight boat I spent a lot of time checking the weight as I progressed. One very useful thing here (especially to avoid wastage) was a cheap digital scale. I bought this from a supermarket for $16 and used it to successfully mix epoxy down to 1g hardener and 5g epoxy. I recorded the weight of each batch of epoxy and I weighed the boat after each major application so I could clearly see the increase from 12kg prior to exterior glassing to 19kg after the fill coats were complete.

I found the fill coats a little painful. I seemed to never quite get the right amount on. I’d put a coat on, sand some off, then try again; many times over. What was particularly irritating here was that to avoid excessive exposure to the epoxy while curing I would make myself wait a few days before any sanding. The time just seemed to drag!

If I was doing it again I’d make two changes.

Firstly, I’d use a slow hardener and warm epoxy/conditions. I found that on a few of my (autumn) evenings the temperature had dropped to maybe 15C and the epoxy had thickened and would spread easily. You want it to spread really easily so a really hot day with a slow hardener would be a better combination.

Secondly, I’d use a random orbital sander more extensively. I spent far too much time continuing on with hand sanding when I should have just used the ROS. The pads clog up quick but crikey it does a hell of a job!

S&G Night Heron – Varnishing and Outfitting

I was initially unsure what to use for the final coat: varnish or polyurethane. The documentation on the net seemed a little confusing. In the end I’ve gone with a varnish from Altex. Not sure if this was the best choice, I suspect it’s more expensive than the equivalent products I could have just bought at Mitre 10 or Placemakers. Nevermind.

The can said 6 to 10 coats. I think I’ve run up 7 on the top and 6 on the bottom. Hard to remember!

I used the ROS with 180 grit pads and this seems to produce a good surface. I’ve still got a fair 250mls left so I’ll put that on sometime in winter.

I enjoyed this part much more than the epoxy. No special safety gear required and it could be done at an enjoyable pace.

I put the kayak in the garage – there was some dust but it pails into insignificance when viewed from a few feet. Runs were definitely a problem. Sponge applicators helped but invariably I’d come back the next day and find a few runs that had formed.

For the outfitting I’ve kept to a bare minimum, at least for the moment. I used window weather stripping for the hatches – seems a bit leaky but I’m sure I’ll be able to tune it better.

I used plastic foot pegs; very light but they also seem a bit flimsy. In retrospect I’d go aluminium.

The back rest provided in the Night Heron plans seems quite effective without any padding. In fact, I spent $80 on closed cell foam and so far haven’t put any in yet, but it doesn’t seem to be especially uncomfortable so I’m in no great rush to finish it.

For the spray deck I ended up, after a few false starts, with getting one made by someone (Gabi) in Nelson. You can get hold of them on TradeMe and I’d recommend the product. Other options include Rasdex and BackOfBeyond.

And the final result? Well, here I am on the inaugural launch in the Waikanae River at the Otaihanga domain. Beautiful spot; you can head out at high tide down the 2kms to the river mouth, play in the sea, then come back with the salt water washed off in the river.DSC03342

 

In the end I guess I spent 10 hours / week from the middle of November 2008 until the first week of March this year. So that’s about 160 hours. The cost is approximately $1000. It’s easy to spend more if you don’t hunt around for good prices on ply, fibreglass, epoxy and varnish.

And performance? Well, I’m very familiar with the plastic sea kayaks that you can hire. My Night Heron is faster, feels more manoeuvrable (and it doesn’t have a rudder) and it’s much lighter. So all in all – I LOVE IT!

Friday, February 27, 2009

Functionally complete kayak

Second to last day of February and a quick note to remind me in the future: kayak is functionally complete. No photograph, camera batteries are flat, but the rubber seals are on hatch rims, the foot pegs are in, the back rest is in. That makes it about 15 weeks from when I started in mid november. Phew. One thing left to do - varnish, maybe wait a couple of weeks to be sure the epoxy has set. Weather this weekend looks shocking. Maybe Sunday to try on the sea? Write some more detail on the last steps of the build after that. For those interested, final weight about 19kgs. Hard to tell, scales difficult to read, maybe 18.5. That's with 6oz everywhere, 2 layers on the bottom and 2 layers most of the inside hull.

Monday, February 02, 2009

S&G Night Heron – Attaching the Deck to the Hull

I found I couldn’t do this with just tape. The hull and deck needed more force to get the positioning of them together so I ended up wiring them together. This was the second time I did this. I did it first time round when wiring together the deck on top of the hull. I probably should’ve put more effort in then with the stern and it would’ve made life easier for me now.

The stern of the Night Heron has to be squashed together with some force. I’m not the only one that seems to have to do this. In the pictures supplied with Nick’s instructions you can see he has it happen to him and I’ve seen pictures from another builder with the same problem:

http://outdoors.webshots.com/photo/1165926632056308877loLvMK – this builder’s comments mirrored my experience exactly

The bow was easy. The last two feet of the stern were stubborn and took a bit of technique. There I used a paint spatula to force out the hull and then pressed hard and fast on the deck to squish the two beveled edges together for taping. One side of the stern just didnt want to play nice...

Maybe an extra form or two would be useful when creating the stern of the boat?

To help with getting the stern to fit I ended up putting in extra stitches along the rear of the boat. Getting them in at the back is easy as long you use long wires and get them through both holes while the deck and hull are still some distance apart. Then, only after all wires are in do you push the deck down onto the hull and tighten the wires.

Attaching deck and hull. The stern was difficult. You seem to need to press down hard to get the hull to expand out and meet the deck on the edges. Finally finished with those wires (except for the stern and bow - I'm going to pack glue and chopped fibreglass in there then tighten up).

I then glued up between the stitches – wish I’d done a cleaner job as I’m still sanding the rough bits up - and then waited a few days to be sure the two pieces wouldn’t crack or pop apart at any point.

With the stitches gone I then put the kayak up on it’s side and taped the inside seam. Notice I cut the hatches before attaching the deck. This made the taping quite easy.

DSC03268

I taped up to maybe 50cms from each end but in retrospect I could have gone further. The secret seemed to be lots of light!

Here’s one bit that went a bit wobbly:)

Oh, I can see it wobbling off to the side there...

(Notice all the sanding dust still left inside!)

 

And then I just had to put it into the pool and proved it worked!

 It floats! (Just taped internal seams and thought it deserved to see water...)

S&G Night Heron – Extra Cockpit Glass

Since I did such a terrible job of glassing the inside of the hull on my first attempt I decided to put a second, large piece of glass on the inside of the boat.

I guess I covered maybe 40% of the inside of the hull with a second layer of 200g glass (equivalent to 6oz), so it should be very strong!

An oversize cockpit area sheet of extra 200g (6oz) fibreglass in the hull. I did this because my first hull fibreglassing left a lot to be desired.

Here’s the finished product. Much better! This time I took extra care to wipe off excess epoxy during the initial curing process and I used a tape edge to stop the frayed glass fibres sticking. 

Much nicer!

S&G Night Heron – Grab Loops

Rather than a big end pour I’ve gone with a couple of small plastic tubes (from old felt pens). I drilled the holes using the stitching holes in the hull as a guide for positioning them on each side of the hull.

To glue them into place I used the chopped up glass, epoxy mix. I wish I’d discovered this earlier. It looks very useful.

I should've discovered this stuff earlier. It would've made a much better way of fibreglassing round the pvc tube Maroske fitting. It's chopped up fibres with a cotton microfibre adhesive additive.

 

Notice the digital scales in the picture. I bought these from a supermarket for $16. They’ve been extremely useful in ensuring I get the epoxy mix right. I use small mixes of typically 36g, 48g, or 60g total weight (the mix ratio for Nuplex R180 is 1:5…).

 Gluing in the loop holders (old marker pens).

S&G Night Heron – Deck Line Fittings

For these I used the Maroske style fitting. I used the instructions on Bjorn Thomasson’s site but in retrospect would do things a little differently.

The first couple that I did I left the pvc tubes in place for more than 24 hours and had a tough time pulling the tube out. In the end I found a hair dryer would blow in hot air and soften the tube sufficiently they came out. For the rest I found if I just pulled the tube out within 12 hours I was fine.

If I was doing it again I’d put a few larger pieces under the pvc loop then cover the pvc with epoxy mixed with lots of chopped up fibreglass then place a couple of larger pieces of glass over the top. I’m sure it would make a smaller, better fitting.

Inside view of one of the Maroske style fittings.

S&G Night Heron – Hip Plates

These were quite easy to position prior to gluing with a few lengths of masking tape.

Positioning both cheek plates.

I glued them into position with a microfibre additive then created a thick fillet and applied fibreglass up each side then a couple more shorter fibreglass pieces to strengthen the joint on the inside (where I’ll never be able to reach again once the deck is attached to the hull).

S&G Night Heron Build Notes – Fibreglassing The Coaming

Quick post. This wasn’t especially easy. Two layers of bias cut cloth. Putting them on wasn’t hard until it came time to push the cloth under the deck. You have to cut darts and fold the cloth under but it’s a tight corner and fibreglass doesn’t like tight corners. If I was doing this again I’d make a rounder corner to fold under. Unfortunately this is neigh on impossible with the thigh braces as you’ve only got the thickness of the ply to work with. Also, I flipped the deck upside down and the glass on the top of the coaming wanted to come off. Maybe I should have waited for the epoxy to gel before turning the deck upside down?

DSC03213

Sunday, January 11, 2009

S&G Night Heron Build Notes – Gluing the Coaming

Well this was a bit tricky! For the life of me I couldn’t get the cutout coaming risers to bend round the curve of the cockpit cutout. I tried kerfing every inch, I tried kerfing much less than an inch (bad idea), I tried a heat gun (good idea). In the end the result was a lot of fine line cracks at the points that I’d cut kerfs. I’m not too fussed. I can easily adjust the final strength by changing the amount of fibreglass I lay on; and now I’ve had success with fibreglassing the inside of the deck that doesn’t bother me one bit.

One thing I was a bit surprised about – how come I couldn’t get the two coaming risers to meet neatly? There was a 5mm gap that I had to plug with a bit of ply. Coaming risers didn't meet together exactly and a shim was needed. Hmm, I should've sanded it down a trifle...

Hmm, just looking at that photograph I can see I should’ve sanded the insert down a mm or two. Nevermind.

The surprising thing for me looking from the top down is how come the top of the coaming still fits neatly. Obviously the risers must have been cut out ok. No problem, it was easy to plug and actually I quite like the way it’s on an angle. I wonder what a riser would look like made of angled strips?

As for the final product see below. Obviously I’ve yet to fibreglass it. Currently I’ve just glued the pieces. I’m going to fillet tomorrow the fibreglass within the next day or so.

Coaming installed. THe cut out on the table was a (failed) idea to help me support a number of uprights to assist bending the coaming upriser.

A quick note here about the use of cyano-acrylate glue. I didn’t use it but I’m thinking perhaps I should’ve. I liked the idea that I could use the epoxy and it would give me time to set it up right whereas I was worried that with CA glue I’d fix into the wrong place too quickly. In retrospect it probably would’ve made the stitching and this coaming much faster.

Thursday, January 08, 2009

S&G Night Heron Build Notes – Fibreglassing

Well this was exciting. What amazing stuff fibreglass is. I read and re-read numerous fibreglassing guides from across the net; use a spatula, use a paintbrush, use a roller. I just came away quite confused.

So I’m going to recount my experiences for you, and probably it’ll just help to confuse you too. Probably main suggestion I have is to find your own way of doing it.

Anyhow, here’s my fibreglassing lessons gleaned from doing the inside of my hull and deck.

Firstly, I think it does make it easier to seal the wood with a thin coat of epoxy first. I ended up deciding that a bit of rag was as good as anything else at applying the epoxy. Wear two layers of gloves to be sure they don’t rip, then dab the rag in the epoxy and rub it on the wood. Worked fine for me and a lot cheaper than any other tool. Certainly means you can apply a very thin layer.

Secondly, for me, rollers suck. I’ve decided that a flat plastic spatula made from the lids of takeaway plastic food containers work great. They’re sufficiently flexible that they can get into funny internal corners easily and they don’t grab at the cloth. They especially good and removing excess epoxy and spreading it away from where it might otherwise pool.

Thirdly, and perhaps most importantly for me, on the internal sides of the deck and hull you should cut the cloth on the bias. This makes a huge difference. The pain with which I watched my first attempts to lay the fibreglass just pull away from the internal corners whenever I ever so slightly stretched the fabric was truly irritating.

Cutting the fabric on the bias (at an angle – 45 degrees seemed good to me) gives it much more stretch on those internal angles.

Here’s the result of my first attempt:

Yikes, how not to fibreglass

Compare that with this:

Wow, my fibreglassing is just sooo much better than my first attempt!

S&G Night Heron Build Notes – Attaching the Panels

This was an interesting exercise. Handling the long hull panels is a difficult task and getting them to fit well is not trivial.

There were a few lessons here.

Alignment

Firstly, get a properly flat work surface to ensure the stations are positioned correctly.

Use a pencil to mark out a long straight edge down one side of the flat surface and mark out the perpendicular lines where the stations should sit.

In the S&G Night Heron instructions Nick suggests holding the stations vertical using a couple of quick clamps. I found that was painful as they’d move out of place whenever I pushed the kayak eg trying to knock an edge off; sand a bump off an edge or generally just touch it...

Instead, lock the stations into place using some scrap wood that’s wide enough to clamp securely into place. In the photo below you can see the deck on the stations and how they’re clamped to the table. (I wish I’d done this while building the hull:))Issues somewhat resolved, time to glue it up.

Bevelling

Next thing to remember is, bevel to the edge. Assuming you’ve cut the panels correctly this should ensure your boat stitches up as it is supposed to. Compare figure A to figure B… I naively would’ve thought that B was preferred to keep all fillets on the inside of the kayak, however, this might lead you to think differently.

bevel and station impact

Nick Schade’s instructions said to bevel so I worked on the idea it was figure B. Checking a station plan against the hull bottom confirms this, so, yes, you need to bevel completely to the outer edge (but not beyond). 001

The best way to ensure you don’t overdo it is to bevel most of the way with a plane or sanding block; loosely tie the panels together; then run a bit of sandpaper up and down the join until the panels close up together. Check the picture below.

How to get that bevel right. Run a bit of sandpaper up and down the connecting sheets to close up the gap.

Stitching

What sort of wire do you use??? I tried copper wire and galvanised steel tie wire. The tie wire worked fine. After reading various messages on the different kayak building boards on the net I was quite confused about what to use. Once you try it you realise you can use just about anything. The important this is that you’ve cut the panels correctly and there is a consistent internal bevel.

Gluing

I found this a bit confusing. Do you use plain epoxy or do you add an adhesive additive like West Systems 403. My current take on it is this: quickly wipe over plain epoxy because it will soak into the wood easily; then add a bit of the adhesive additive (made up of microfibres and colloidal silica I believe) and paint into the joint. You only want a minimal amount to actually glue the joint together. Don’t worry about forming a fillet during gluing.

If you have trouble removing stitches after the glue has set I found that the commonly repeated advice to use a soldering iron works great.

Filleting

For the filleting I used a lightweight filler (from Epiglass I think) and masking tape. Masking tape is great.

I tried lots of methods to apply the fillets: a plastic spoon worked great, a wooden stirring stick shaped like a doctor’s tongue depressor worked great and I think I could easily have cut any bit of plastic to a round shape to form an applicator. So all in all, it wasn’t very hard.

Monday, January 05, 2009

Stitch and Glue Night Heron Build Notes – Cutting the Panels

There are a few important points here which I learn’t from the process.

Scarfing.

I used the jig described in the One Ocean Kayaking building manual. It worked but my implementation of the jig wasn’t that great. In retrospect I think I might in future either do it by hand using a sharp plane, or use a router jig I’ve seen on the Kayak Forum.

Holding onto a circular saw and ensuring it cuts cleanly and evenly across the ply requires a fair bit of attention and a good horizontal guide with a clean, straight edge. The first piece I used was too thin and had a slight waiver in the middle. Better to make it nice and wide so it remains a true straight edge.

The ply sheets are thin with external veneers and an internal core; the saw is rough, so use a bit of waste material as the bottom and top layers. I ended up with the top and bottom sheets having some tatty edges (because of course I didn’t use the waste material top and bottom).

Clamp or weigh down the center of the sheets otherwise the middle has a habit of lifting.

Finally, check before you’ve finshed that the scarf is accurately square to the long edge of ply. Use a large builders square. If I had I would’ve seen I had a waiver in the middle of my scarfs.

Plywood scarfs with an unfortunate wobble in the middle

Scarf Gluing

This would’ve been a whole lot easier if I didn’t have that waiver in the scarf!

Having said that, the output hasn’t been that bad. There was some badly overlapping ply, and I really should have taken more time with the weighting down of the joint, and actually, in retrospect I went too light with the epoxy, but in the end it appears to have worked fine.

Just one note on the use of the epoxy. This was the first time I’d used the epoxy and if there’s one lesson with doing anything new – it’s give yourself time and opportunity to learn from your errors. I’ve tried a few different methods of application in the last 2 weeks and my current favourite is the nylon brush topped foam pads that are sold in the hardware stores as speed brushes. I can buy the pads for just a few dollars and they stick onto a plastic holder which, at least for me, is easier to work with than a roller.

I think the best approach is to mix up some epoxy, run a quick line of it up and down the scarf edges to allow it to soak in; then add an adhesive filler, give it a swirl and apply it to the edges before joining. This will help fill voids better than just epoxy itself.

Cutting the Panels

First discovery: positioning the paper patterns on the ply with spray on glue was a breeze. I was worried that I’d permanently stick the patterns on but it was surprisingly easy to apply a thin coat that would allow me to reposition a pattern. Having said that, I did end up using a couple of different spray glue brands. The 3M glue seemed to be far better to use.

I also used a string line for the main pattern that included the hull pieces. This is such a long paper pattern that I wanted to be sure that a center line drawn on the pattern actually ran straight down the table. Getting this wrong would be annoying as you’re cutting through two ply panels not just one.

I drilled the tie wire holes next and put little bits of wire in the lot of them to keep the panels from moving; then just for overkill I decided I’d hot glue round the edges of the two panels. I used a sharp hobby knife to cut round the pattern edges – surprisingly easy to do. Then I used a jigsaw to cut out each piece. The jig saw did a good job (I think) but the best method appeared to be to stay a mm or two away and use a block plane or sanding block to finish. That gave a very good finish. Just to give myself time to improve I purposefully cut the stations first.

Since cutting the main panels I’ve actually moved to using a fine point panel saw. It’s just less noisy, less dusty and more accurate for the straighter lines.

Lifting the cut pieces was alarming, They wobble a lot and by experimenting with offcuts I could tell the scarf joints could break at the point the ply starts to thin. There was often no epoxy at that point and when combined with a thinning (or complete lack) of external veneer, the ply was substantially weakened. My advice: don’t go too light on the epoxy round the scarf joint, and make sure in the positioning of the pieces that the inner ply layer isn’t left substantially exposed anywhere along the joint.

If you do get a dodgy joint just try a wood backing block. In the case of the photograph below I’d been a bit aggressive and planning away some badly overlapping ply on a scarf. The result was a weak point so I then thinned a piece of scrap ply down and glued that onto the joint. I later sanded this down so just a thin veneer was left covering the low points. It appears to have fixed my problem nicely. (Note that I decided to put a thin epoxy coat on panels but at the time I took the photo I hadn’t epoxied under the clamp.)

Backing block for a weak scarf

Stitch and Glue Night Heron

Over recent weeks I’ve been building a stitch and glue Night Heron kayak designed by Nick Schade from Guillemot Kayaks. There’s a lot I’ve learnt along the way so I thought it useful to post up some notes on the blog.

As a quick background to the project, the Night Heron family of kayaks are 5.5m ocean going sea kayaks available in plywood hard chin form or strip form. Check out the web site as there’s a lot more information there. Of special use when building is the Kayak Building Bulletin Board hosted by Guillemot. This is a great resource.