 Poster: A snowHead
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Carbon fibre sheet is pretty often used as a replacement for fibreglass in ski building to seperate out core/top sheet & core /p-tex base. You can also use carbon fibre box section as a core replacement for wood (usually in the form of a monocoque). The reasons for use differ. As sheet it adds stiffness when resined up that exceeds fibreglass sheet and can save weight as well. The core usage saves weight and again can add stiffness.
The problems regading re-use have been well covered above BUT if you come across some spars that are carbon fibre our little collective might be interested in them to see if we could recover enough to use as core material. They would have to be quite thin - 20mm max.
Masts would be way too thick and are not suitable for ski re-use 'as is'. There might be a way to re-use them if one could create an 'MDF type' solid sheet composed of mechanically ground up carbon fibre masts which are then added to resin and heated under extreme pressure until the resin is set. This should create a matrix that is strong enough for many purposes but is probably not going to be as strong as the original mast. This sheet might be really good for house building apart from anything else since you could create modular shapes that would be light but stronger than current options.
Having a thought - if we did this 'MDF/carbon fibre' pressing in the form of a ski and varied the widths we could get a ski in one pass that would have variable flex where we wanted it.
How many of those masts did you say you could get your hands on ....?
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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| RattytheSnowRat wrote: |
| There might be a way to re-use them if one could create an 'MDF type' solid sheet composed of mechanically ground up carbon fibre masts which are then added to resin and heated under extreme pressure until the resin is set. This should create a matrix that is strong enough for many purposes but is probably not going to be as strong as the original mast. This sheet might be really good for house building apart from anything else since you could create modular shapes that would be light but stronger than current options. |
I know that you can make boat hulls using this technique.
You'd probably want to go hunt down an appropriate engineer to verify this, but I rather suspect that the tensile strength of fibre composites is quite closely related to the length of the fibres in them. I suspect that this sort of amorphous carbon fibre composite will not have the sort of mechanical properties you'd want in a ski.
| RattytheSnowRat wrote: |
| How many of those masts did you say you could get your hands on ....? |
There's a graveyard of old windsurfing equipment in the kitstore of the local club. I don't know how much carbon might actually be in em, but there were numerous dead masts there last time I looked. I'll have a peek next time I'm in the neighbourhood. Each mast is about 5cm internal diameter at the base and >4m long; there's a lot of material even in a single mast.
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Serriadh,
You may be right but the logic of the composite sheet approach is that the strength/flex after such a process is equal in all directions. I appreciate that it might not be that simple i.e. the process would certainly never give the subtleties of ski manufacture from multiple materials in multiple combinations and orientations BUT it may make a good beginner/intermediate ski for a very accessible price. Anything that gets more people into skiing is OK in my book (as long as they use a different lift queue form me).
Just hooked this off the site I posted above re; RAMP skis:
"The structures are totally new. We are using a new FSC Certified Bamboo core material that is three times as expensive as the industry standard Poplar Cores. They are also three times as hard. The result is the skis feel like rock solid and stable like metal race skis and the greenest possible material as it is very rare for bamboo to have the Forestry Stewardship Certification. We are using domestically made composite materials that are much more expensive and high performance. For example we use a full layer of kevlar. This material is six times more expensive than fiberglass but is eight times better at absorbing vibration. When a ski flexes the bottom layers are being stretched, the top layers are being compressed. We use Kevlar in the bottom of the ski as it is so resistant to stretching-deformation. As a result dramatically better energy and rebound. This is why it is great for bullet proof vests. We use a domestic resin from Entropy called super sap. It is pine byproduct-based vs petrochemical-based so it is the greenest possible material that also provides amazing adhesion and durability. We also invented a new graphic printing application that makes the skis look like hand painted art that goes fast."
"We developed a whole new way to make skis with vacuum molding vs the old traditional presses that have been used since the 60's. This is the method used now to make aerospace products like a modern composite helicopter blade. Vacuum molded skis have a much different feel. In press molding you have four atmospheres of pressure squashing materials straight down against camber plates. The layers are forced into un-natural shapes. As a result the skis get extremely sensitive to very small variations. In vacuum molding we use 1/4th as much pressure and it is equal in every direction. The layers change shape according to their normal thermal expansion characteristics. As a result the line of the ski is perfect and the sweet spot is huge. When you combine this big sweet spot with the rock solid feel of the bamboo core AND the Kevlar benefits the feel on snow is amazing. We were at Mt Hood four times this summer and it was very exciting."
Sadly that excited me quite a bit …..
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Anyway, snowHeads is much more fun if you do.
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| RattytheSnowRat wrote: |
| You may be right but the logic of the composite sheet approach is that the strength/flex after such a process is equal in all directions. |
Indeed, but the forces working on a ski in use are not. Have a quick peek at http://www.on3pskis.com/gallery/construction/ and you'll note that the sheet of carbon fibre they use in their layup is basically unidirectional, because it is there to contribute to lengthwise stiffness and springiness, as lengthwise bending will be the strongest force a ski experiences and the largest displacement, etc. I wonder whether a composite made of short, randomly oriented fibres might have to be laid down in quite thick (and hence heavy and inflexible) layers in order to stand up to the same sort of punishment. Why are there no composites experts lying around when you need one?
The RAMP skis stuff sounds interesting, but they're going a bit overboard with the 'OMG so expensive!' routine, I think  Interesting that they use vacuum bagging vs pressing, but I've no idea how to tell if their list of benefits is just marketing hyperbole or if it is genuine and everyone else has been doing it wrong. I'd be surprised if the end result was a noticably different ski.
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| feef wrote: |
| I'm no expert, but it was covered in my Mech Eng course at uni. |
Care to summarise? 
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chopped fibres are normally shorter and lying in random positions and directions. If you have a requirement for strength in a particular direction, it's better the fibres are orientated in that direction, or woven with other fibres to improve strength in that direction and plane. You might find cases where you've got the warp (the fibre running along the direction) and weft (across) made from different materials. You also get tri-directional weaves where there's one warp and two wefts are 45 degrees rather than perpendicular.
To get the same strength from chop, you'd have to have enough of the stuff that the random placement of fibres guarantees a similar number running in the same direction as in a weave. As you can imagine, that's quite a lot more material.
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| feef wrote: |
| To get the same strength from chop, you'd have to have enough of the stuff that the random placement of fibres guarantees a similar number running in the same direction as in a weave. As you can imagine, that's quite a lot more material. |
Yeah, that was basically my intuition about the matter. Nice to have it confirmed by someone who isn't just guessing
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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I did my dissertation on particle reinforced composites, or well modelling them.
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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actually.. doing some more reading and light research, there seems to be some evidence to suggest that a structure similar to that of F1 safety cells, which are laminate of aluminium honeycomb sandwiched between carbon fibre might be viable, however, while the safety cells are very stiff and don't flex much, the research uses a less stiff laminate and fills the honeycomb code with a PVC foam to introduce elasticity into the structure.
While I'm all for wood and traditional methods, I also like pushing the boundaries 
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You know it makes sense.
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I'm still of the opinion that a carbon fibre composite is viable for a ski IF we do some serious testing on comparative dimensions. What would really get me excited is if we could get away from metal edging and get a carbon fibre edge of sufficient strength to substitute. If we just stick to the ski types that require de-tuned edges front and back, I don’t see why it would not be feasible. It would require a pretty tough mould/former tho' and some serious heat/pressure to get to the required tolerances.
Serriadh, theres no issue with getting the required directional characteristic, you just create slightly thinner cores and lay a reinforcing sheet as carbon fibre weave under the top sheet as they already do over wood cores. That would address the issue you are raising and is already proven tech. TBH I think we could get the same effect by cunning width control and shape (e.g. ridges, voids and vents layed into the carbon fibre 'core' as it is formed)
Still - prob. several steps too far for us (at the moment).
(I’m starting to feel significantly under-informed in the face of my colleague’s educational achievements.)
feef,
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which are laminate of aluminium honeycomb sandwiched between carbon fibre
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I think that's what they do for some of the pricey top end custom skis already - aluminium ally monoque strengthened with carbon fibre.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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Serriadh,
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Interesting that they use vacuum bagging vs pressing, but I've no idea how to tell if their list of benefits is just marketing hyperbole or if it is genuine and everyone else has been doing it wrong. I'd be surprised if the end result was a noticably different ski.
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I think the reason they are keeping it quiet is that they are not actually bagging per se but doing controlled vacuum infusion. The issue with a ski press is that the controlling the epoxy layering is difficult so the tendency is to overdo it. This means that the amount of epoxy used in a press is way more than required and also that it is not always well directed in the layering. The advantage of the infusion process is that less epoxy is used and the penetration into the layered materials is greater meaning even less epoxy is required. This gives the same mechanical strength BUT with less width and weight. I think that's what they are doing and it would have aesthetic, cost, quality and timing benefits. If you combined it with certain parts of the bagging technique it could provide much tidier as well, which also assists timing and quality. The end result would depend on a number of factors but if you used exactly the same core/reinforcement layer/top sheet/base you should get a lighter ski with the same strength for less cost and fuss with vacuum infusion compared toa press – not bad really. Downside is probably the initial capital cost of the equipment - but I understand that’s dropping. The pressures they are talking about are consistent with vaccuum infusion techniques as is the helicopter blade comment.
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Poster: A snowHead
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| RattytheSnowRat wrote: |
Serriadh,
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Interesting that they use vacuum bagging vs pressing, but I've no idea how to tell if their list of benefits is just marketing hyperbole or if it is genuine and everyone else has been doing it wrong. I'd be surprised if the end result was a noticably different ski.
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I think the reason they are keeping it quiet is that they are not actually bagging per se but doing controlled vacuum infusion. The issue with a ski press is that the controlling the epoxy layering is difficult so the tendency is to overdo it. This means that the amount of epoxy used in a press is way more than required and also that it is not always well directed in the layering. The advantage of the infusion process is that less epoxy is used and the penetration into the layered materials is greater meaning even less epoxy is required. This gives the same mechanical strength BUT with less width and weight. I think that's what they are doing and it would have aesthetic, cost, quality and timing benefits. If you combined it with certain parts of the bagging technique it could provide much tidier as well, which also assists timing and quality. The end result would depend on a number of factors but if you used exactly the same core/reinforcement layer/top sheet/base you should get a lighter ski with the same strength for less cost and fuss with vacuum infusion compared toa press – not bad really. Downside is probably the initial capital cost of the equipment - but I understand that’s dropping. The pressures they are talking about are consistent with vaccuum infusion techniques as is the helicopter blade comment. |
Vacuum bagging vs Pneumatic press.
Vacuum holds all our materials together while the epoxy sets, Pneumatic (can) squash all the materials together. If all your parts are exact you can have an equally good ski as you can form pneumatic press. However a press can squash everything into place the way a vacuum bag can't
A vacuum system is very good at getting epoxy into all the nooks and crannies so you end up with a strong ski, in a press you have to wet out all the parts or hope that gravity will get the resin to where its needed.
A pressed ski will be lighter than a vacuumed ski, unless you skimped on the resin which is bad, the press squashes it out.
Vacuum infusion is only necessary when your resin is adversely (badly) affected by being open to the atmosphere, or you are trying to get s=resin into everything. you don't use it to limit resin/cloth ratio.
Helicopter blades and similar stuff is built in an autoclave - a pressure vessel used to increase the pressure from outside to double, tipple or more the pressure when vacuum bagging,
Vacuum bagging is great for making ski prototypes (see davide's build logs on skibuilders), very cheap, very adaptable, no problem to go from 145 twins to 190 powderboards!
Pneumatic Press is about consistency, it's much easier to make 100 pairs exactly the same than with vacuum bagging.
My original setup which we made 10 or more pairs with was nothing more than some plastic sheeting, cardboard, duck tape and an old fridge motor!
Over the 10 skis we did improve things to add a pressure shutoff for the fridge motor, Bluetack like substance for closing the bag and better breather layer in the bag.
Our tips were always pre bent and we pressed against a 6mm sheet of maisonite!
I now have a 50psi (approx 20 tonne) temperature controlled, sliding loading tray pneumatic press
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Thanks for that Idris, nice to see some 'real world' experience of the two methods.
I've also discovered that polyester resin 'boils' when vacuum bagged so is only suitable for pressing. Not that that's a big issue since we're talking about using epoxy, but interesting all the same.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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Cheers Idris - always good to hear from some one who's been there/done it. That set up you describe with the fridge motor is one I am going to try (got the plans) but I'm going to substitute in a vacuum pump from a car as I think they can get higher pressures and are meant to be a bit robust. One tip that I heard for a breather system was a piece of twine placed round the inside rim of the bag with one end taped over to leave it outside the bag. Apparently it's meant to give a very small, regular air pathway into the bag which helps a lot.
I think (???) that the autoclave bit for helicopter blades is where the heat has to be applied at a high pressure (Boyles Law/Charles Law, etc.). I guess it would work for skis but I'm dubious that any substantial benefits would really accrue over standard techniques. There should be some productivity gains from the time benefit but is anyone really churning out skis 24/7 (in any event, I thought that helicopter blades were initially formed by hydraulic pressure anyway?) Helicopter blades need to withstand forces way, way beyond anything a ski would encounter and cost a fortune to ensure that they stay in one piece. I don't see RAMP rushing to autoclave for the run size they do but I could be wrong. I still suspect that it's an infusion/bagging/heating tweak of some kind where they've tweaked the bagging part of the action to 'industrialize it. Electro magnetic edge strips over a standard+ flexible bag would be the thing I would look at. That way you get the speeds of a press with the benefits of bagging. If you could combine that with a very precise method of epoxy application and a heated base for bagging operation, I think you could have the best of both worlds. Apart from anything else, wouldn't an autoclave that could hold a ski cost an arm and a leg?? If they were applying increased localised air pressure under heat rather than a vacuum, what other benefits would accrue for ski formation (other than producing a really HOT ski)?
Still now that I've shelled out for the hose we are def. going to be building a press. Right? .... Right, lads? .... I said ri .... I'm speaking to myself, aren't I?
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| RattytheSnowRat wrote: |
Still now that I've shelled out for the hose we are def. going to be building a press. Right? .... Right, lads? .... I said ri .... I'm speaking to myself, aren't I? |
I think a press is the way forward for us, certainly.
Now that Lola has definitely gone bust, I'm going to keep my eye on local liquidation auctions for anything that could be useful, although I think an autoclave you can fit a car in might be overkill.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| RattytheSnowRat wrote: |
Cheers Idris - always good to hear from some one who's been there/done it. That set up you describe with the fridge motor is one I am going to try (got the plans) but I'm going to substitute in a vacuum pump from a car as I think they can get higher pressures and are meant to be a bit robust. One tip that I heard for a breather system was a piece of twine placed round the inside rim of the bag with one end taped over to leave it outside the bag. Apparently it's meant to give a very small, regular air pathway into the bag which helps a lot.
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A fridge motor will be slower than a vac pump from a car, but it is much stronger and pulls a much much higher vacuum. I have a laboratory pump and while it is intended to run non stop and the fridge motor isn't we only use it as a backup as the fridge motor pulls a deeper vacuum - just slowly.
An average air con type vac pump (does not matter if its domestic or car) pulls about 85% vacuum, The lab pump about 92% and the fridge motor 99.5%
There are lots of tricks and tips with the breather system, but we quickly ended up just using painters boarder paper (like butchers paper) over the ski and a thick layer of cardboard around the hose connection to stop or at least reduce resin getting into the vac hose.
Build yourself a resin trap (can be made form a jam jar) before destroying your first vac pump!
My shutoff valve was a 250cc vets syringe (for feeding lambs) with a big spring and a momentary push button cutoff switch, and a nut/bolt on the spring to adjust pressure - pressed many skis with that rig, stopped the fridge motors form running all the time and overheating (but that normally doesn't happen for a few days at least!
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| Quote: |
Build yourself a resin trap (can be made form a jam jar) before destroying your first vac pump!
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already done (it's an old quality chutney jar with strong glass sides and an adapted reinforced lid)
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My shutoff valve was a 250cc vets syringe (for feeding lambs) with a big spring and a momentary push button cutoff switch, and a nut/bolt on the spring to adjust pressure
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nice - thanks for the tip . I'll probably use an old refurbed bicycle pump as I have one but I suspect I will be moving on to your set up.
The reason why I was going for the car/van pump was that it is used to continuous working whereas yer average fridge unit - as you pointed out - doesn't like to work all the time. Still, I have now been informed and shall change plans accordingly. Thanks.
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I think an autoclave you can fit a car in might be overkill.
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yup - but you now have a van don't you?
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| RattytheSnowRat wrote: |
yup - but you now have a van don't you? |
I have a van which is partially converted into a camper, and a diesel lift pump waiting to be fitted, yes
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Well done, m8! Now it's just the rest of your 834 projects that you have to shelve or shut prior to spring.
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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| RattytheSnowRat wrote: |
| Well done, m8! Now it's just the rest of your 834 projects that you have to shelve or shut prior to spring. |
After being frozen stiff in the tent at the rally the other weekend, I've got the motivation to get the van finished and running again
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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Oh dear. I hope all your bits are now functioning again. Sounds like 'motor-vation' to me!
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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| RattytheSnowRat wrote: |
| Oh dear. I hope all your bits are now functioning again. Sounds like 'motor-vation' to me! |
yup.. also because I could use it for impromptu trips up to the highlands over the winter, drive up, kip in the carpark and be first in line on the lifts in the morning
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Hey,
I have been away with work since I last commented and I have only just had a chance to catch up!
Ratty - I'm definitely keen to muck in with a press. What kit do you have so far and what are the big ticket items you are keeping an eye out for? My old company had a brand new vacuum pump that had never been used - it's part of the kit used for making subsea joints in cables. I stored in somewhere safe in the yard...I'll check with an old colleague to see if it is still where I left it.
I'd better go and swot up on all the information that everyone's been churning out the last couple of days.
Dave
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You know it makes sense.
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yup.. also because I could use it for impromptu trips up to the highlands over the winter, drive up, kip in the carpark and be first in line on the lifts in the morning
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SHOTGUN! - that's where I learned to ski (destination Glenshee, I am assuming)
dalamb84, Dave, m8. Welcome back! I'm def up for the vac pump if it's going for my experiments in bagging (youa re more than welcome to join in if you wish) but the target for the co-op is a press which requires positive pressure. I think feef has an appropriate compressor but I'll let him take that up. Big ticket - steel for the press frame and prob some form of electric sheet heating system. I'd also like to start with a modular ski shape former but the rest of the gang has remained rather quiet on that point. Otherwise it's just all the fiddly bits - clamps for the hose we have sourced, valves and line to connect the hose to the compressor, bolts for the frame. feef has big ideas for the finish of the frame so I'll let him discuss that but I think if we can score some RSJ's that are looking for a new home that would be superb. Otherwise I thought that we might get lucky and source some form of steel frame that was already in the correct dimension (e.g. a box section of a portable crane or the like), Obviously the gold standard score would be to source a 2nd hand 2m x 1m bed variable setting hydraulic press or an actual ski press for a very reasonable price.
Idris, m8 - my brain works better when it's not fully switched on. This occurred to me in the half light between awake and asleep - double bag, exterior super tough, interior bag stretchy, toughish and flexible. You lay out the ski on the former, slide it into a very thin bag with an absorbant pad to catch any runoff , slide that into the double bag and seal the end, pump heated water into the outer bag. The inner bag would form around the ski/thin bag and pressure would be applied from all sides very evenly (the water would self equalize the pressure). If you needed extra external support you could slip the whole package into a large piece of steel pipe with a lid and base (all the flows could be built into the lid that you just clamp down to shut). You control the heat very easily by pumping hot water around under pressure. Air flow/exit to the inner bag via a valve inserted at the closed end of the bag through which you could circulate filtered air. Very controllable 360 degree pressure, very controllable heat and the worst thing that could happen is a puncture. It wouldn't be to autoclave standards but it should solve a host of issues. Best thing is the set up is very light and very portable.
Actually - do we want to score a large piece of pipe instead of a steel frame? We could just insert the hose in between the pipe and the former and exert the pressure that way. Dave, m8 - any 2m long x 3m diameter bits of steel pipe lying around? We could go concrete pipe if it's robust enough.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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| RattytheSnowRat wrote: |
feef has big ideas for the finish of the frame so I'll let him discuss that but I think if we can score some RSJ's that are looking for a new home that would be superb.
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It's nothing QUITE so grand, and it's also something we could probably retrofit with a bit of work. Just trying to make our life easier in terms of handling the press, indeed my hope is that it could become a one man operation, which most of the existing designed are more certainly not.
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Poster: A snowHead
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Black anodised alloy components and polished stainless steel structure.
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I believe was your comment , Mr feef .....
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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| RattytheSnowRat wrote: |
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Black anodised alloy components and polished stainless steel structure.
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I believe was your comment , Mr feef ..... |
heh.. that wasn't to be taken too seriously.. Although it is something I've got plenty of access to
My ideas are more surrounding the mechanism for opening and closing the press
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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I guessed you were not being too serious - for now.
The standard variation on sliding the whole sticky mess sideways into the press seems to be a rising platform. I suppose the other option is some sort of hospital trolley affair where the mold/former is supported from below whlst in the press but you can wheel it in and out on wheels when the press is open - that would speed things up a bit.
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You need to Login to know who's really who.
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RIGHT!
Just been told the muppets that sold me the hose sent it to the wrong address and someone else signed for it. I shall be on a hose hunt tonight (no, wait, that didn't sound right .....). feef as you ahve the comrpressor can we ask you to hunt out the correct valves and hoses to connect up the hose to your compressoe? I'l start working on sourcing the appropriate epoxy to seallt eh hoses (unless someone already has the info?)
What else?
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| RattytheSnowRat wrote: |
RIGHT!
Just been told the muppets that sold me the hose sent it to the wrong address and someone else signed for it. I shall be on a hose hunt tonight (no, wait, that didn't sound right .....). feef as you ahve the comrpressor can we ask you to hunt out the correct valves and hoses to connect up the hose to your compressoe? I'l start working on sourcing the appropriate epoxy to seallt eh hoses (unless someone already has the info?)
What else? |
Look at skibuilders, angle iron on both sides, 4-6 bolts straight through the whole lot, do em up good and tight, should be good for 100psi - if you need to seal use tire cement.
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You'll need to Register first of course.
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| RattytheSnowRat wrote: |
I guessed you were not being too serious - for now.
The standard variation on sliding the whole sticky mess sideways into the press seems to be a rising platform. I suppose the other option is some sort of hospital trolley affair where the mold/former is supported from below whlst in the press but you can wheel it in and out on wheels when the press is open - that would speed things up a bit. |
Don't over complicate, the nicest sliding loading tray I've seen is Leaf skis one - again see skibuilders
Mine is just a pair of large wooden supports that let me slide the lower mold straight out, they are just topped with painted plywood works fine for many tens of pairs of skis so far.
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[quote="RattytheSnowRat"]
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Idris, m8 - my brain works better when it's not fully switched on. This occurred to me in the half light between awake and asleep - double bag, exterior super tough, interior bag stretchy, toughish and flexible. You lay out the ski on the former, slide it into a very thin bag with an absorbant pad to catch any runoff , slide that into the double bag and seal the end, pump heated water into the outer bag. The inner bag would form around the ski/thin bag and pressure would be applied from all sides very evenly (the water would self equalize the pressure). If you needed extra external support you could slip the whole package into a large piece of steel pipe with a lid and base (all the flows could be built into the lid that you just clamp down to shut). You control the heat very easily by pumping hot water around under pressure. Air flow/exit to the inner bag via a valve inserted at the closed end of the bag through which you could circulate filtered air. Very controllable 360 degree pressure, very controllable heat and the worst thing that could happen is a puncture. It wouldn't be to autoclave standards but it should solve a host of issues. Best thing is the set up is very light and very portable.
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Maybe something like that, but not until you are at least 10 pairs into the project.
Plastic sheet larger than your bottom mold + enough to fold over it to create an envelope - lay up your ski on the mold, cover with breather, fold over the other half of the envelope - seal with tape or or sticky putty or whatever - switch on your vacuum system - Done
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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| RattytheSnowRat wrote: |
RIGHT!
Just been told the muppets that sold me the hose sent it to the wrong address and someone else signed for it. I shall be on a hose hunt tonight (no, wait, that didn't sound right .....). feef as you ahve the comrpressor can we ask you to hunt out the correct valves and hoses to connect up the hose to your compressoe? I'l start working on sourcing the appropriate epoxy to seallt eh hoses (unless someone already has the info?)
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no problem.
I've already got a spare compressor hose lying about that we can use.
Fixings : I've got the quick-release fittings for the compressor end. I'll do a bit of digging about to see what would be best for the host end. If it comes to it, I could fabricate something.
For expoxy, have a look at the easycomposites link I posted the other day, they do epoxies in small enough quantities to get us started.
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Idris, thanks for all the good advice, m8. I'm a bit belt and braces so I'll do the clamp and glue with tyre cement just to be sure. feef is hooked on a one man operation for the press, I'm with you on the KISS principle. We talked above about an adaptation of the 'bolt it through' method above and I think we will go with that subject to other opinons being expressed.
I HAVE HOSE!! idiot couriers left it at the wrong address with people to whom that package was not addressed. No bloody wonder so much stuff goes AWOL.
I had a look at and complieda list of a whole host of suppliers who seem primarily foccussed on stuff that floats. If it's good enough to keep your nads out of the water, it's good enough for me. The entropy resins link I psted above is from the RAMP guys who seesm to ahve done a lot of comparative testing before lumping with that. Idris, they reckon it's very eco if that's any use to you. I'm all for saving the planet where I can (as long as I avoid de-lamination, that is). Happy to go with whatever is suggested but the top and bottom sheets have to epoxied with stuff that dries super-clear
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