Ok, thanks Warren

http://motoform.blogspot.se

A highly polished aluminium surface is best to release from.  A minimum of 6 layers of EasyLease should do the job.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks for your reply,
My budget for this is quite good, so I will have a aluminium mandrel made to my spec,
would you recommend a polished surface on the mandrel?
I intend to use easy lease, how many applications on aluminium?
The plan is to heat the tool to around 25C, and after completion use the cold outside to "shrink" the mandrel for slightly better release,
would you recommend against that?


(how about split female tool, wet lay and internal pressure bladder, might work?)

/Petter

http://motoform.blogspot.se

Great success can be had with using the shrink tape. It is the method used on many roll wrapped tube constructions. Although the outside diameter will not have the same tolerance as the inside, it could be surface ground to get the tolerance needed. The rest is down to a good quality mandrel.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

HI Warren
Thanks for replying.

I agree that it would be difficult, however I have never tried the shrink tape method, but I guess its quite easy?
The outer diameter is quite critical in this product, but I plan to make the tool longer than needed,
so the desired diameter just be located further along the length, self adjusting.
But the thickness and taper must be very accurate, do I have control over that with the shrink tape method?
Also, undisturbed weave of the top braid is a must, will it twist from the tape?

/Petter

http://motoform.blogspot.se

It should be possible to make such tubes although infusion would be particularly difficult if you wanted to make the outside face the moulded face. This is particularly difficult due to the small size you wish to produce.  In a practical sense it would be very difficult to get all the backing stack into the tube and still insert a bladder or vacuum bag.

A male mould will be much easier to work with.  Again you could infuse but it would not be the easiest to do at that size.  A more practical method is to use a steel or aluminium mandrel, then wet lay the carbon fabric around it to get the desired wall thickness. the shrink tape would be used to consolidate the fibres and give a smooth finish overall. You could quite easily sand off the ribbed finish the tape leaves and then polish to a high gloss finish.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Hi all

I need to make 4 tapered tubes, approx 800mm long with 28mm diam one end and 35mm other end.
I am aiming for carbon braid but might also make another 4 in flax, maybe in UD, so compatibility for that
is good to consider to some degree.

But I can´t seem to make my mind up on what method to use and what type of tool to use,
budget is good, so milled alu is possible, or lathed.

The problem as I see it is the diameter, is it possible to infuse inside a toll with this dimension?
I say no if we talk about dist net and bag, traditional infusion (I have infused tube this way before but with diam 100mm ish)
So is it possible to infuse with a bladder inside the braids?

Or should I not infuse at all? Lathe a Alu core/rod and do traditional wet-lay and shrink tape?

Buying prefabs is totally ok, just haven't found any in my dimensions.

Open for suggestions, Thanks
/Petter

http://motoform.blogspot.se