Franken-Board

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Franken-Board

mattma
Administrator
It was council clean up day on the weekend and while i was tossing out a lifetime of easily replacable crap I discovered that I have enough bits and pieces of various failed attempts at building a boards that collective i now have enough to make one albeit with pieces that are not really fit for use -wood core is very dry and splintered a bit, some Klegecell that I damaged with a mixture of acetone and ABS plastic shaving when i was trying to make liquid abs, some ABS strips that were a bit crooked on one side and a handful of ss nuts for inserts.

So I am going to have a crack at making the 'franken-board' with all this flotsome and see just how long it will last. I have enough FG and resin to make it and when done that should clean my supplies out so I restock with new stuff after I get back from a trip up north to kite the Trade Winds in far north queensland.

The outline will be the wake board I designed a long time back on BoardOff and Lex cut it for me on his CNC machine.

I'm going to make it with 6mm Paulownia base and 6 mm Klegecell as top layer. I'm going to stick to my usual layup of 450gm stiched e-glass + graphics + 140gm surfboard quality plain weave e-glass.

No concave this time and about 40mm of rocker, continuous.

I have another copy of the Chinese Morning Herald with images of Angelina Joley and our Prime Minister to use for graphics:) Becauses I havent' got a lot of time to do this one I'm not going to pre-cure the skins. However, the one experiment i am going to indulge in is trying to heat the glass and resin to see if I can defeat the air bubble Harbinger. Also keen to try the hot layer finish ( a final coat applied with a heat gun to thing it out and speed up the cure).

So here is some of the mostly-not-fit for purpose stuff

Poorly milled wood core - warped


Half of the Klegecell top deck

The Wake Board Template cut by Lex


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Quick and Dirty Router Table

mattma
Administrator
This post was updated on .
To put a really shallow angle on the Klegecell I knocked up a router table in the spirit of the Franken-Board


(sorry about the blur but I think you get the idea:)





And used it to chamfer the edges of the Klegecell





Next decision is how to do the inserts. I'd like to leave gluing the layers together until its on the rocker table to try to minimise spring back. The fly in the ointment though is how to do the inserts - brass T-nuts that Kaos69 had specially made. I think I will glue them into the kelgecell by turning the deck upsidedown and gluing the top ( small end) into the klegecell. Then when I go to do the final layup I will fill the insert holes in the lower deck with heavily qcell'd resin to set the larger end of the t-nut into it.

This way I can glue some of the rocker and concave into the board rather than trying to bend what is now a 12mm core. Hopefully this will reduce spring back.

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Re: Quick and Dirty Router Table

downunder
Hey Matt,

how was the dust when routing Klegecell? One of the reason I cut it with a hot wire is dust which I hate...Never tried routing it tho.

Got a heaps of inserts if you ever run out of it...

PS

I see a channel's on your core:) Do I see it right? Gee, I wonder how will you vacuum it? I was thinking to put some balsa under the core + vac film but it is a lot of work to profile balsa, I guess.
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Re: Quick and Dirty Router Table

mattma
Administrator
Hi downunder

Dust was terrible. The router cuts the Klegecell well ( doesn't tear it) but there is a lot of dust. I was thinking of making a cutting wire like your because I have some nicrhome wire but I don't have a DC source handy. I would have had to move the whole operation to the van and use the spare battery.

I was watching some videos the other day of some guys cutting polyurethane cores and EPS cores for sufrboards and windsurfers and they use CNC's with a router on it. Seems like overkill for cutting foam. Given how easy it is to cut through the foam with a hot wire I wonder why they don't make a hot wire CNC machine. You could get away with much weaker stepper motors and could even have specially shaped heads to make one pass in cutting any kind of recess into the cores. Maybe the lack of versatility..

I have planned on having channels but if I am running out of time before we head of on our trip I might skip it.
The plan was to cut them in with a plan and take a cast of them using car bog (which is polyester resin with chopped fibres in it). I'd wax these up and put them down on the rocker table surface the just do the layup normally. i think ( like your original rocker table) casting with some cheap material is the way to go. The unknown is whether there will be enough flexibility in the bog. If not then maybe I'll only put channels in the largely flat tips.

Thanks for letting me know about the inserts. When I'm back from up north I'll probably have a go at some thicker baords. My limitation to date has been making thin cores which the inserts would be too high for.

Cheers
Matt




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ABS Rails

mattma
Administrator
I think I may have cracked bending ABS strips for the rails after a lot of different approaches.

I clamped the MDF template to the table and jammed the abs between the template and a stopper ( piece of ply screwed into the table. The I heated it up with heat gun until gets soft and pliable ( 30 secs or so). Then using a long straight piece of wood and starting where its jammed in between the template and stopper I just pushed the plastic against the template. The bit of friction there keeps the bend part of the strip already bent tight against the template. ABS has a very clear point at which it becomes pliable and ceases to be so. As soon as it stopped conforming I stopped and heated it again. Then I put stoppers at the tip and the end to hold it in place and let it cool for 10 minutes until it was back to ambient tempreature. As soon as it came off it kept its exact shape.





I bent the two ends and the side rails ( which probably wasn't necessary but when you have a hammer everything looks like a nail). Normally I would have then glued the rails to the sides of the core but that involved another round of mixing epoxy and waiting. So this time I thought I'd try sticking the pieces together and make the rail into one piece so that it can just be put down when everything else is laied up rather than do it in a separate step.

To glue them together I made ABS glue by dissolving ABS offcuts in acetone. I works very well. This is a tip I picked up on a 4x4 forum where people were repairing ABS parts on their cars. The acetone creates liquid ABS and when applied to the parts to repair the acetone dissolves the surface to be repaired, the ABS glue fills the space between the faces and then the acetone evaporates off. you effectively melt them together.

This is really only practical where you have a thin layer of glue doing the bonding. What I mean is that if you try to cast something with the liquified ABS it will take a very very long time to harden. This is because it hardens by the acetone evaporating. However, if you have anything except a very small volume of it then the outside hardens but it then traps the acetone inside the hardened skin and the liquid ABS inside can't dry out. I tried to pour fin inserts this way on the Klegecell piece that I'm using in this Frankenstein board and not only did the acetone destroy the foam, it hadn't dried after about a week so I cut them out and put foam back in.

As there was very little glue needed I found that just putting acetone in jar and stirring it with a left over piece of rail was enough to liquefy a thin layer of ABS on the left over trail piece. I then scraped this off and on to the ends of the rail pieces and butt glued them. I did this while things were still clamped in places from being bend into shape because I wanted to make sure the ends where held together tightly while it dried.

I haven't test the strength yet but I have dropped the single piece rail a number of times and accidentally twisted it in a door and so far so good.



The above  pic shows the rail and the high tech ABS liquification apparatus.

I decided in the last minute to leave one of the ends of the rail un-joined because I thought it would be a good idea to do a final fitting it around the actually core in case I have changed the core shape in the process of sanding. Smarter way would have been to finish the core first and then use the core instead of the rail.
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Re: ABS Rails

downunder
This is gold Matt!

If there is a way to make this thread "pinned", I would do that:)
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Re: ABS Rails

mattma
Administrator
Thanks Dean.

I don't know if there is a way to pin it. But I might copy it across to the idea exchange so its not buried in the project.

Me and the wife and dog are hitting the road in a week heading for the warm trade winds in cairns. I am really hoping to get some time to finish the board up before we go. I'd love to have a new toy to play with up there.

cheers
Matt
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Quick and Dirty Rocker Table

mattma
Administrator
I had a chance to do a bit more on the board today in between packing to head north for 4 months of trade winds!

I have 6 days before i am on the road and still have work and packing to do so from here on its about doing this board quickly. The first corner I cut was with the rocker table. Unlike my other boards where I've always keen one eye on their low wind performance this board is going to be a bit more wake like. this means more rocker. Largely a continuour arc. I had hoped to experiment with channels but time has beaten me and so I decide to put some concave in. 10mm of concave and 60mm concave which after spring back I'm hoping for 5mm concave and 40mm rocker. As the core was already glued up from some time back I wasn't able to leave the planks just spot glued in place to reduce spring back.

Instead of cutting new jigs for the new rocker I used 2 peices of 250x50mm treated pine. To get the rocker line I took the perspex sheet I'm using for the rocker table surface ( 6mm this time) and proped it up at bot tips and let it sag in the middle. This very roughly gives the flat tips but more curvature in the middle that I have in my other boards. I traced the line of it and routed a 10mm channel along the line.



I made two and then pushed the perspex into the channel and put ratchet ties around each end to hold it together. Ta da!!!! The 1/2 hour rocker table.  

To add the concave I built up the mid section under the able. It did lift the whole table so I had to screw it to the work bench with huge roofing screws.



So, next was starting to get some of the bits prepared to go under. I finished the rails by putting final small piece of ABS and gluing it together into a continuous piece. I was worried that maybe when the I put the rocker into the deck that the length of the bottom face of the board would increase enough to distort the rail or break the glued sections apart but that wasn't the case so I joined it together so that it was really snug fit.



I was thinking that I would just put together the kit of pieces at the time I did the lay up but when i was sizing up and gluing the rail I realised that the rail was very likely to fall off while the pressure was being drawn down and have it lodged under the board so I decided just to tack it in place with some 5 minute epoxy. I tacking in half a dozen spots only. I want the resin to push up through the gap between the rail and the deck when doing the lay up because I am pretty sure that will give much better penetration of the resin and better bonding.




Next step is to see what glass I have on hand.
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Re: Quick and Dirty Rocker Table

downunder
Whooow - 4 months of trade winds sound awesome!

I just got back from Singapore this night. One really needs escaping
from a daily routine, from time to time:) Marina Bay Gardens is a
must, as well as swimming on the 57th floor:)

Yes, was thinking the same thing with routing the perspex channel to
slide it in a peace of wood. Good someone did it before me:)

Cheers
D.
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Re: Quick and Dirty Rocker Table

mattma
Administrator
A bit more progress tonight. Managed to grab a couple of hours just to cut out the glass and sort the inserts into the board.

I used M6 SS nuts again and set them in resin via a 12mm deep hole drilled in MDF. I squashed baking paper into the holes. I put a few millimeters of 5 minute epoxy to stand them off from the bottom. then put the nut in and then filled it with normal epoxy.

I'm giving the Crazy Fly idea a go- putting some FG over the insert holes and pressing the insert through. To keep them there I just put a drop of 5 minute epoxy on one spot on each of them. i just want to make sure they don't fall out when i go to assemble everything but don't want to get in the way of the resin flowing up and around the inserts when I lay it up.



When i pressed the inserts through it did cause the FG underneath to gather so that in some places it overlaps. This wouldn't be an issue with a high pressure press but whenever I have had overlap on the underside it has been enough to stand the next layers of FG off the table so that resin had to flow in and fill the gaps which looked like crap. So where it overlapped here I just cut a V shaped section out so it was one layer everywhere.



I also cut out all the FG and release film, breather/bleeder material and vac bag.

Although its not an off cut or left over like I was planning on doing for the board made from left over stuff I decided to use the basalt fibre for the first time. Its 300gm and I'll use it to replace the 180gm surfboard glass that I was going to use. The websites say its about 30% stronger than  S glass. So the total weight of material is 450gm stitched e-glass and 300gm basalt and its Bling as all Shit!

Just righting this makes me think that i had better put some time into thining out the tips or this board it going to have that landing on concrete feel on one of my other ill fated boards.




One thing i've discovered about myself is that despite my best efforts to just throw this board together with whatever I had left over or damaged I found myself getting very attached to making a great end product. I have i haven't planted the seeds of its early demise by using some of the garbage I started out using.........
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Re: Quick and Dirty Rocker Table

mattma
Administrator
In reply to this post by downunder
Sounds like a very nice escape. Just for relaxation or work too?

Our trip to FNQ is part holiday but working remotely all the time so it will be working and kiting in a sunny place. I love it up there and there is a great crew up there, especially in Port Douglas.

The wood channel seems to have worked okay. Its a bit wobbly but I know that would be the case I use a bit that is larger than the perspex is thick so that any wobbles can even out when the perpex goes in. It was certainly quick. And afterwards i am going to dismantle it and use it to around the bottom of the fence to kee our chickens from escaping. Very multi-purpose:)

You getting any wind over your way?

Cheers
Matt
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Re: Quick and Dirty Rocker Table

downunder
Yes, very, very nice. Pure relaxation on the 57th floor and 150m long
swimming pool:)
The Marina Bay Sands Gardens are like a light years from the
infrastructure in here. The Zoo too.
Airport-Marina Bay train ticket is S$2.4. What to say...

Anyway, no wind at all and working like 9hrs/day. My contract might
expire in 2mnths & than we are heading to the EU, hopefully:)


On 5/27/13, mattma [via BoardBuilders Forum]
<[hidden email]> wrote:

>
>
> Sounds like a very nice escape. Just for relaxation or work too?
>
> Our trip to FNQ is part holiday but working remotely all the time so it
> will
> be working and kiting in a sunny place. I love it up there and there is a
> great crew up there, especially in Port Douglas.
>
> The wood channel seems to have worked okay. Its a bit wobbly but I know
> that
> would be the case I use a bit that is larger than the perspex is thick so
> that any wobbles can even out when the perpex goes in. It was certainly
> quick. And afterwards i am going to dismantle it and use it to around the
> bottom of the fence to kee our chickens from escaping. Very multi-purpose:)
>
> You getting any wind over your way?
>
> Cheers
> Matt
>
>
>
> _______________________________________________
> If you reply to this email, your message will be added to the discussion
> below:
> http://boardbuilders-forum.1077691.n5.nabble.com/Franken-Board-tp963p987.html
>
> To unsubscribe from Franken-Board, visit
>
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Under the pump!

mattma
Administrator
Got an early mark today and so did the deed on the new board.

I've got a 5mm thick piece of perspex as the rocker table surface now and it really is rock solid. When it when under the vacuum not a sign of any deformation like my old one so am happy about that.

The only new thing I tried this time was to work with a heat gun to try to saturate the glass more and get rid of air bubbles. Won't know until it comes off the table how successful its been in getting to the holy grail of no  post-finishing but I did notice that it saturated parts of the 450gm stiched glass which wouldn't saturate just by hand with a squeegy. I could see bubbles percolating up from the weave but there is no way to tell if the more deeply embedded bubbles were broken.

I realised that the hot air does two things. It makes the bubble expand and the resin things so you get a double wammy. I had to place the hot air gun quite close to the surface (maybe 5 - 10cm) and when I did the bubbles breaking up was clear to see.

Another unknown it just just much it will have accelerated the curing. The resin still seemed pretty mobile when it went under at about the 1 hour mark.

The glass weighed 1170gm in total and I mixed 1300gm of resin all up. This was about right to get coverage of the board with a hand layup but under the pump a lot came out so hopefully the ideal 50-50 resin/weight target is hit. Unforetunately a bit too much came out and because I only used a single layer or breather material it got soaked quickly and so I could feel a few lumps forming where the excess resin was getting trapped. I guess the lesson here is to use ample breather material to blot up the excess.

I tried pre-warming the glass to see if that would be enough to help wet the laminate out better but I don't think it did. I think the mass is too small and so as soon as cool resin hits it the temperature of the glass pretty much drops to ambient temp I'm guessing.



So here goes the first layer of Basalt down. I think this may be a world first ( give me 24 hours before you send pictures of other boards made with Basalt fibre so I can bath in this moment!:). The first kiteboard on the planet made with Basalt Fibre!!!!!!)



It has this amazing copper sheen to it. However, when it was wet out with resin it went translucent so not exactly sure what the end product is going to look like.



I still find this an very exciting moment. When the vacuum pump starts and you see the film starting to pull the board down.









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Re: Under the pump!

downunder
Quite possibly the first one, indeed!

Question, are you glassing both sides at one go?  And, the routed channel on a wood plank, did you use some sort of template for the routing? Looks very decent cut if done just by the hand:)

Cheers

D.
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Re: Under the pump!

mattma
Administrator
Hey D

Yes, glasses both sides at same time. It still takes me about an hour to do both sides and have never had any problems. I only ever do resin work late at night so that probably helps keep things mobile.

The channel in the wood was just by hand following a line I traced using the natural fall of the Perspex sheet suspended at both ends. There is a bit of wiggle in the channel that doesn't really show in the pictures and I used a.9mm bit for a 5 mm thick sheet so that the wobbles wouldn't get in the way of  sheet fitting. I had the router on quite high revs and moved very very slowly along the line.

I've been post curing it this evening so should have it off the table tomorrow.

Cheers

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Off the table

mattma
Administrator
The exciting moment. What the, will they, why the.....

Here she comes...


The finish on the underside it excellent. A vast improvement over previous attempts with far fewer pin holes. However, there are some that still survived the heat treatment but I'd say only about 10% of the number from the previous board.

the distortion in the image in the mid section is due the concave.

Its a bit hard to see but the basalt in the light has a amber/red color to it. It looks a lot like stained hardwood. However, the color is quite dependant on how much light is bouncing off it. In more direct sunlight its more translucent and the wood grain underneath shows through ( this is the stained hardwood look) but out of direct sunlight it goes very dark and looks like carbon.



The weave of the stitched glass used under the basalt shows through strongly here. No a look I like on its own but in combination with the very slick bottom I think the contrast works pretty well.




I did a rough cut with the multi-tool (sonic tool / felix tool) so just need to drill the holes now.

I put 60mm of rocker in it assuming that 20mm would be lost to spring back. Hmmmmm, didn't happen. Zero spring back. On one hand that is a great outcome because it means the amount of rocker and concave is exactly what I put in but it leaves me with a board that is more like a genuine wakeboard. Maybe that will be a good thing. Won't know for a while.

I think some of the contributing factors to the lack of spring back is the approach of only tacking things in place. So, all the planks where not fully glued together, the rails where just tacking in place and the upper deck was completely seperate and was only placed down as part of the layup process. This means that the rocker and concave to a large extent are glued in place rather than trying to bend a 12mm core and hold it with the laminate. for example, because the upper deck wasn't glued to the lower deck prior to bending the rocker into it the upper deck could slide over the surface of the lower before bonding to it.

Also, the upper deck was foam so it would contribute nothing to the internal stresses that lead to spring back. So it was a 6mm wood deck with the compound curves glued in place rather than only bending them into place.

To make this work the resin needs to be mobile enough and there needs to be open enough spaces in the between the pieces being glued that the resin can get in. I'm guessing that the heat gun may have helped to some extend here as it thinned the resin for a short period of time. I also put the heat blanket over the board for about 20 mins once it was under the vacuum to also help with the resin's mobility.






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Re: Off the table

nono19
what a jump weapon! simply fantastic!!!!!!!!!!!!!!
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Re: Off the table

downunder
In reply to this post by mattma
Hey Matt, it does look good!


How difficult is to cut this stuff and what's the weight after?

Just a thought, since you going to the FNQ I recon this baby will be
on a strong sunlight and might be good to paint the top deck to some
light color. The foam under might get extremely hot otherwise. Test it
on a Sun, takes 1min...This is a real pain with a closed cell.
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Re: Off the table

mattma
Administrator
Thanks guys.

Packing the house and the van to get on the road beat me in the end. I trimmed it and drilled pilot holes for the inserts but didn't get the chance to finish the board off. I did bring it with me though and will look for an opportune moment along the way to finish it off - mobile board building factory!!!

Matt
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Re: Off the table

mattma
Administrator
We made it away amid the pouring rain of Sydney and have reached the 1000km mark. Landed at the mother in laws place and she has a well equipped shed! The last two things to do were drill the insert holes and sand the rails after the rough cut.

I didn't have a chance to do any finishing on the surface so I'll have to keep it rustic until I'm back in Sydney near my beloved tools. :)

today I drill the holes. Again, I've gone for drilling all the way through because with the small SS nuts in there the chance of delaminating due to bolts that are too long is great. I just drilled a small pilot hole all the way through after putting a strong light underneath it to find the holes. I drilled 4mm hole first then used a counter sink bit to open it up on the underside. Then turned it over and drilled it from the top using a 1/4 " bit which was slightly oversized. I just drilled down until it touched the top of the bolt. Then screwed in a bolt to push all the wax out.






It looks black but the color is very reliant on the way the light hits it. The top looks black but you can see in the next photo the dominate color of it when you see it close up. Its sometimes an beer bottle amber color and sometimes its a hardwood red color.





I'll get a chance to finish the rails once I get to Cairns.

After 5 days and having it strapped on the roof under a ratchet strap it has sprung back a bit but only a small bit. It was 59mm on Sunday and today its 51mm.

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