1.
INTRODUCTION
Following a series of prototyping trials carried out at RAL on a variety of test assemblies, these instructions attempt to provide what is considered to be the least complex and most reliable methods and procedures for the construction of the inner thermal enclosure (ITE). These should be considered as recommendations only, based on our experiences and should be understood to be guidelines rather than strict explicit instructions. No attempt was made during the prototyping phases at RAL to produce a complete full scale ITE, but several small models were made to test the viability of the construction method for the full size enclosure. These trials were based on the production of series of short cylinders of Ø300 mm diameter, which being smaller than the ITE would challenge the build methods, due to the increased difficulty of manufacturing smaller cylinders.
A number of construction techniques were applied, but only those that were consistently successful are reported in this document. However, a flexible approach should be taken that best suits the preferences of those involved in producing these components. It should therefore be left to the discretion of the team to decide on the best methods of construction and not necessarily follow to the letter what is reported here.
Before starting manufacture of the endplates, it is strongly recommended to carry out a few small test trials so as to get some confidence in the procedures. It may also be found during these trials that alternative techniques may provide a more successful end result, which may be dependant on the available facilities and tooling at CERN.
2.
MATERIALS AND TOOLING
NOTE: most of the tools and materials are standard stock items and should be readily available. For the vacuum bagging materials, SP Systems supply all the necessary specialised tools, materials and fittings. Their website contains all the information required for both purchasing the materials as well as vacuum bagging methods and procedures. The following link contains all of this information: http://www.spsystems.com/solutions/solutions_pdfs/pdfs_productdatasheets/vacuum_consum ables/vacuum_consumables.pdf
The following materials and tooling are required to complete the ITE:
 AIREX® foam sheet 5mm thickness – spec R82.80 (sheet sizes 2.7m x 1.2m)
 AIREX® foam sheet 8mm thickness – spec R82.60 (sheet sizes 2.8m x 1.35m)
 KAPTON® film 0.025mm thickness – aluminised on one surface only (supplier:
Sheldahl – description: VDM;1.0MIL,*SH*4’x115’)
 Epoxy adhesive – Araldite 2011 (AW106/HV953U, 100/80pbw)
 Aluminium foil (50 micron thickness) to make glue trays.

 Cu-Kapton film (supplied by RAL from GTS)
 Colouring additive: Araldite DW 0137-1-BLACK
 Vacuum bagging consumables (see note above):
 Vacuum bagging film (polythene sheet)
 Sealant tape
 Release film
 Peel ply
 Breather/bleeder fabric
 Vacuum fittings
 Vacuum pump
 Electric hand-held router ( défonceuse) with Ø5mm rectangular slot cutter
 Precision weighing scales for measuring resin and hardener proportions.
 Soft-bristle paintbrushes (40mm wide) and artists brushes ( Ø3-5mm)
 Neoprene rubber gloves
 Cleaning agents: ethanol, isopropyl alcohol.
 PFSR sealant remover (Allchem) for wiping off excess uncured epoxy.
 Rolls of cotton cleaning tissue
 Flat working surface table of sufficient length and width to fully support Airex foam.
 Scalpel blades and scalpel holder
 Scissors
 Masking tape
 G-clamps or carpenters panel clamps
 Linoleum or linoleum like plastic sheets, sufficient to cover working surface
 Long steel rule or builder’s ‘Straight Edge’
 Engineer’s square
 Hand-held vacuum cleaner

3.
PREPARATION
All supplied materials must be stored in a clean, dry environment and should be left in their containers until assembly is about to commence. The Airex® foam is particularly sensitive to moisture penetration and this will require priority care during storage.
The assembly environment must be clean and dry; ideally with climate control to ensure the humidity levels remain relatively low. The working environment temperature will need to be in the region of 20º C to ensure that the epoxy cure times are not excessive. However it would be an advantage to be able to increase the room temperature (to approximately 25º C) to reduce the curing time of the epoxy once the Kapton films have been fixed and clamped
The method used to support the mandrel will be left to the discretion of the production team.
The structure would need to be stable for reasons of safety and be at a location where all-round access to the cylindrical surfaces is possible. It should also be at a height level convenient for working on. The carbon fibre inner cylinder must be unobstructed and be free to rotate about the mandrel.
3.1
Preparation of the Airex® foam sheets
A suitable working surface is required to support the foam sheets during the cutting processes.
The minimum working table dimensions required would be 2.1m x 1.65m and the working surface must be flat and have a smooth, non-porous finish. A covering of a few millimetres thickness of a material like linoleum would be most suitable as a base for the cutting operations.
All working surfaces must be kept as clean as possible and rubber gloves should always be worn when handling foam sheets and films. Generally, gloves should be changed at regular intervals throughout the components’ construction, especially during the bonding phases.
3.1.1
Cutting sheets
The Airex sheets are 1200mm wide and according to drawing TD-1012-432 (sheet 3 of 5), a width of 1623.5 is required to allow sufficient material to completely envelope the outer surface of the carbon fibre cylinder. This width also includes a little extra (approximately 10mm), so that when the vacuum bagging is carried out, the foam goes into circumferential (hoop) compression, to ensure a good bond line is obtained on the opposing edges as they butt together during the gluing.
Initially, a simple test should be done to check that this width is correct by cutting a single strip of Airex (1623.5mm length by ~10mm width) and wrapping it around the outer surface of the carbon fibre cylinder to see that an overlap of approx. 10mm is obtained. Once this is verified, the sheets can be cut and bonded together to form one complete sheet.
Place the linoleum sheet over the working surface. Remove a single sheet of the 5mm Airex®
R82.80 foam and place on top of the linoleum. Position the engineer’s square and the rule on the foam where the material is to be cut. In this case 423.5mm width needs to be removed to make up the correct sheet width of 1623.5mm (1200mm + 423.5mm).

It is important to ensure that sufficient pressure is applied to the rule to stop it slipping. This is best achieved by clamping the assembly to the surface table using G-clamps. Use a scalpel to cut the foam, running the blade along the edge of the rule; this is best carried out with several swipes, progressively cutting deeper and deeper through the foam. The scalpel must be used with some care to ensure that the edge cut remains perpendicular to the plane of the surface of the foam.
Using the hand held vacuum cleaner, remove any traces of Airex dust that will have been produced during the cutting. Go over both sides of the sheet with the vacuum cleaner to remove any other traces of dust and debris. Remember to ensure that the working surface is also clear of any dust and debris.
The epoxy 2011 is made up from 100 grams of A (resin), 80 grams of B (hardener) and 1.0 - 1.5 grams of the black colouring paste (Araldite DW 0137-1-BLACK). Mix the required quantities to these proportions and apply along the full length of both an uncut 1200mm sheet and the
423.5mm sheet cut before. This is best done using a soft bristle paint brush using a stippling or patting action with the flat side of the brush, as shown in FIG. 3.1. The glue should be seen to cover the full 5mm width of the foam sheets and along their full lengths.
FIG. 3.1
Following the illustration in FIG. 3.2, place two straight wooden batons or metal bars on the surface table and clamp into position. Ensure these batons are set parallel and that their

distances apart are less than the desired width of the foam by 2-3mm. This will ensure that the contacting surfaces are in full compression.
FIG. 3.2
Place a piece of release film over the working table at the position of the glue-line and then place the two pieces of foam on top, bringing the two glued edges together in the manner depicted in FIG. 3.2. A piece of masking tape can be put over the joint to keep them together.
FIG. 3.3
Place a second piece of release film along the top of the foam joint and apply a load along this region to force the bottom surfaces in contact with the surface table, as shown in the illustration in FIG. 3.3. A simple baton of wood with a weight on top could be used to maintain pressure as the glue cures. It is possible that a small amount of buckling of the foam may occur between the unconstrained regions, but these can be removed by applying extra loads over these areas if

necessary. Leave the remaining glue in the glue tray close by so that it can be used as a guide to the state of the glue cure at the join line.
After the glue has set, dismantle the assembly and remove the release films and any masking tape. Carefully inspect the joint on both sides checking for any discontinuities and place on the cutting table. Also check that the width of the sheet has not changed significantly from the correct sheet width of 1623.5mm Using the same method as before, cut the foam to its correct length on the drawing. This should be done by removing foam at each end to take out possible misalignments between the two sheets when they were originally brought together. This will ensure a clean cut at each end.
3.1.2
Cutting of slots
To cut the slots, the router will be guided by wooden batons clamped to the table with the foam sandwiched between them, as shown in FIG. 3.4. It is recommended that several test pieces are practised on to ‘get a feel’ for the router and to understand how to set up the baton positions accurately so that the cuts are straight and true and the cutting depths are set correctly.
FIG. 3.4
The hole (detail T on the drawing) could be cut by making a template, in this case a flat sheet of steel with a hole drilled through it. The plate would be clamped in the same way as the wooden batons and the same cutter used to work out the foam material up to the edge of the hole.
Finally, remove the clamps and again remove any foam dust accumulated from both the foam and working surface using the vacuum cleaner.

3.1.3
Kapton lining of slots and fixing of gas inlet insert
The slots are lined with aluminised Kapton to prevent any moisture that may be present in the purged gas entering the foam matrix. It is also used to seal the gas channels and prevent the ingress of loose foam particles from circulating within the system. In all of these slots it should be remembered that it is the Kapton side NOT the aluminised side that is bonded to the foam.
FIG. 3.5 illustrates the method used for shaping the Kapton inside the slot. A film of epoxy is first applied to the walls and base of the slot using a narrow (3-4mm) artist’s brush. Strips of
Kapton are then forced into the slot using the forming tool. The forming tool can be made from any preferred material, but it was found that Airex foam produced satisfactory results. The shoulder on the forming tool is needed to prevent build-up of glue seeping from the slot onto the edges of the top of the slot walls, which otherwise tends to lead to the formation of ridges.
The width of each Kapton strip is not critical and although the drawing specifies a flap extension of approximately 2.5mm on each side, the amount of excess Kapton in the flap is down to the construction team to decide.
FIG. 3.5
The forming tool should run the full length of the slot and be left in place for the duration of the cure. Two adjacent slots could be lined simultaneously, so that the load on the forming tool can be applied with weights placed on a bridging platform spanning the two rows of slots.
After the glue in the slots has cured, the excess flaps can then be bonded to the top surface of the foam in a second gluing operation. To ensure an even contact pressure and maximum bonding strength it was found that a load applied to a rigid plate distributed through a foam rubber cushion was very effective (see FIG. 3.6).
The order in which each slot is lined is for the construction team to determine, however the logical order would be to line the longitudinal cuts first followed by the lateral cross-cuts (refer to FIG. 3.7).

When all of the slots have been lined it is necessary to ensure that all the longitudinal cuts crossfeed into the lateral crosscut. In FIG. 3.7, cut ‘A’ will need to be made to clear the Kapton in the lateral liner so that it ventilates into all of the longitudinal cuts.
The ‘closing films’ are not added until the foam has been cylindrically formed. The final stage before forming the cylinder is to cut and bond the ‘insert liners’ followed by the ‘gas inlet insert’. This is bonded into the hole by applying glue to the surface indicated in FIG. 3.6.
NOTE: It is essential to ensure that the gas feed vents on the outer cylindrical surface of the insert are aligned with the lateral crosscuts. Also, check that there are no traces of glue obstructing any parts of the component. During the curing of the glue, pressure needs to be applied to the region local to the insert against the surface table to ensure that the top and bottom planes of the insert are flush with the external foam surface planes.
FIG. 36.

FIG. 3.7
4.
ASSEMBLY OF FOAM TO CARBON FIBRE CYLINDER
The method used to form and fix the foam cylinder to the carbon fibre cylinder is by vacuum bagging. As mentioned earlier, the Airex sheet is cut slightly oversize. During the vacuum bagging, the atmospheric force causes the foam to compress circumferentially and in so doing radially contract against the outer surface of the carbon fibre cylinder forcing the foam into intimate contact with it.
4.1
Preparation of vacuum bag
Using the information on the following link, purchase the necessary materials and carefully follow their recommendations: http://www.spsystems.com/solutions/solutions_pdfs/pdfs_productdatasheets/vacuum_consu
mables/vacuum_consumables.pdf
The essential elements of the vacuum bagging process is summarised by the illustration in FIG.
4.1. The polythene sheet must first be carefully cut to size, taking account of the extra thickness of the foam when it is ready to be fixed.

FIG. 4.1
The polythene sheet must have sufficient length to extend beyond the foam so that it can be taped to the mandrel outer surface as illustrated in the schematic in FIG. 4.2. Two annular end pieces also need to be cut to surround the end-flange. These pieces are joined together using the sealing tape to form a leak-tight barrier.
A hole is cut in the sheet at a convenient location so that the exit of the vacuum fitting can pass through (an example of these fittings is shown in FIG. 4.3). This fitting is then sealed in, using the same tape.

FIG. 4.2.
FIG. 4.3

4.2
Application of glue
Before any of the gluing operations are carried out, ensure that the inner surface of the ITE carbon fibre cylinder and the outer surface of the mandrel is clean and free from any traces of rust or any other loose material. It is important that the cylinder is free to slide with minimal resistance over the mandrel. This may be assisted by applying a thin dry lubricant such as a
PTFE spray to the mandrel or anything to prevent the cylinder binding on the mandrel .
The foam sheet is placed slot side down on the surface table and a quantity of epoxy plus colorant is prepared. The epoxy is applied using the soft bristle paintbrushes. Due to the large surface area to be coated, this process is time consuming and would require the involvement of
FIG. 4.1 several assistants divided up at various regions to share the task. The glue is applied by patting the wider side of the brush against the foam as shown in FIG. 4.1.
NOTE: Ensure that each of the two joining ends have glue applied to them in the same manner as shown in FIG. 3.1. The effectiveness of this joint is critical in ensuring that the formed cylinder is dimensionally accurate and retains circularity.
The foam is now ready to be positioned around the carbon fibre cylinder. This will require the assistance of several helpers. The mandrel must be positioned so that the cylinder is accessible from both sides. The foam should be passed under the mandrel and wrapped over the cylinder from both sides. The ends of the sheet can then be forced to meet somewhere near the top of the cylinder. Masking tape can be used to temporarily align the ends together to ensure that they butt up rather than overlap.
Before fitting the vacuum bag, inspect the join-line to ensure the ends have not moved out of alignment. The sealing tape needs to be applied carefully so that there are no folds or creases formed in the polythene. Once this is complete, the vacuum line can be connected and the pump switched on. As the air is being removed carefully go round each region and check for

signs of leaking. This can usually be heard, especially if a length of PVC tubing is used, as form of stethoscope. Leaks can be stopped by sticking extra pieces of normal plastic insulating tape onto the sheet in the regions where there is a suspected leak or they can be plugged with bluetack or some other type of putty. The sheet should appear to be tightly gripping the cylinder as seen in FIG. 4.2.
FIG. 4.2.
After the glue has cured, stop the pump and release the vacuum. After removal of the polythene bagging, closely inspect the cylinder for any irregularities, especially at the bond line joining the foam ends.
The open Kapton lined channels in the foam now need to be enclosed by adding the closing films as shown in FIG. 3.7. Aluminised Kapton strips are cut to a suitable width to bridge the channels and are bonded into place by applying a glue layer to the Kapton lining extensions on top of the foam and the surrounding foam. Again the Kapton side of the film should be bonded with the aluminised surface outermost.
4.3
Attaching of Copper-Kapton outer film
During the prototyping trials carried out at RAL, two approaches were tried in trying to attach the Cu-Kapton to the outer surface of the foam. In both cases the glue was applied to the foam in the same way as described earlier, using the brush. The first method involved compressing the outer Cu-Kapton with heavy-duty cargo straps to distribute a uniform radial pressure over

the whole surface. The second method used the same vacuum bagging that was used previously for the forming of the foam sheet.
In both cases the results were disappointing and the surface of the Kapton contained numerous wrinkles and creases as seen in FIG. 4.3. It was clear that the applied pressure was forcing any slack in the Kapton film to ride over itself to form these ridges. Once formed, they were reinforced by the glue underneath and were so numerous that any thoughts of repairing them seemed impractical. The worst examples were produced by the vacuum bagging method, since the resulting pressures were much greater than when using the straps.
FIG. 4.3
The only way to eliminate this problem would have to involve tensioning the film as it is laid down over the foam and maintaining this tension load throughout until cure. For reasons of time schedule no further attempts were made at RAL to develop a satisfactory solution to this problem, but a number of suggestions are made here on how best to proceed.
It would clearly be advantageous to be able to dispense the Cu-Kapton directly from the roll onto the foam, since the film is already difficult to handle when cut from the roll and is easily creased. It is envisaged that a spindle be attached to the mandrel to support the roll and enable

the film to be dispensed directly. Alternatively, a separate freestanding structure can be constructed to support the spindles and tensioning system as shown in the illustration, FIG. 4.4.
FIG. 4.4
In this scheme, the end flange on the cylinder is fitted with a handle, mounted onto it using a few of the available inserts in the flange. These inserts should be carefully inspected to determine that they are strong enough to deliver the required forces. It may be necessary to use a larger number of inserts than those shown in the figure.
In this way the ITE can be rotated about the mandrel. The support structure is fitted with two spindles: a long one for holding the spool to which the Cu-Kapton roll is fixed; and a shorter one for holding the disc/drum of pulley 2. At the end of the spool there is fixed another disc/drum (pulley 1), identical in size to pulley 2.
The pulley cable is routed to a third pulley supporting a block of weights, which applies a tension in the film through pulley 1. As the ITE rotates and the Cu-Kapton unrolls, pulley 2 feeds the cable at a rate equivalent to the cable uptake in pulley 1. A constant torque needs to be applied against the direction of rotation of pulley 2 to maintain the height of the weights as well as to prevent them falling to the ground. This will be manually operated if simplicity is required and will also need to have a locking mechanism to lock the pulley in position when all the Cu-
Kapton has been dispensed to the ITE and left for the glue to cure.

The Cu-Kapton roll width is 1200mm and so two pieces of film will have to be applied to cover the whole ITE, with a circumferential join line lying somewhere midway along the cylinder length. At the flanged end, the full 1200mm width of film can be laid down, however care must be taken to avoid fouling the inserts on the inner surface of the flange, as shown in FIG. 4.5. This means that a small region of foam on the cylinder will not be covered in Cu-Kapton.
NOTE: It is essential that this method be tried and tested on the cardboard cylinder first to be confident it will work on the carbon fibre cylinders.
The laying down of each of the sheets has to be done in two stages. Firstly the end of the sheet needs to be restrained to prevent it from slipping as the tensioning forces are applied. The simplest solution is firstly to bond the end of the sheet to the foam outer surface along a narrow region at the end of the sheet. This will act as an anchor for the film, tightly constraining it to the foam cylinder wall. It is probably recommended to use plenty of glue in this region to ensure a reliable bond. The second stage, after the glue has set, is then to continue laying the rest of the Cu-Kapton film around the cylinder. The glue is first applied to the Airex foam outer surface using the same methods as before. The Cu-Kapton is then wound around the cylinder using the apparatus described in the paragraphs above and as illustrated in FIG. 4.4.
The second Cu-Kapton sheet can then be fitted to the other end of the cylinder in the same way as the first sheet. In this case the second Cu-Kapton overlaps the first by about 10mm (see drawing TD-1012-432 sheet 1/5).
FIG. 4.5
After curing, any excess film from the second sheet that extends beyond the cylinder needs to trimmed flush. The soldering of the circumferential overlap should be left until the remaining components have been added. All soldering instructions are found in Ref. 1.

4.4
Addition of Airex foam to carbon fibre flange
The foam should be cut according to the dimensions on drawing number TD-1012-432 sheet
5/5. The work guidelines used to manufacture the rear thermal pad should apply to this flange since the materials and construction methods are almost identical. A template should be made to accurately cut the inner and outer radii of the annulus and for cutting the holes. The outer
8mm x 10mm rim on the outer circumference of the annulus should be bonded into position first and left to cure according to the drawing.
A sheet of Cu-Kapton should be cut to form an annulus with larger internal and external diameters of the foam (plus rim) outer diameters. The approximate dimensions are shown in
FIG. 4.6.
FIG. 4.6
The Cu-Kapton film is then glued in the usual way to the foam by applying the epoxy to the foam and bonding to the Kapton side of the film.

After the glue has cured, the remaining excess film hanging off the foam should be snipped with scissors or a scalpel, in a radial direction as shown in FIG. 4.6. The interval between each cut should be no larger than ~ 20mm. Also, clear the holes of the Cu-Kapton using a scalpel.
The flange can now be integrated with the cylinder by bonding it to the carbon fibre flange on the cylinder. The tabs on the outer radius of the foam flange need also to be folded over it and glued to the back face as shown in FIG. 4.7. Pressure will need to be applied to the back of the foam to ensure good contact with the carbon fibre flange (FIG. 4.7). It is possible that vacuum bagging may be done to achieve this, using the same bag as was used to compress the Airex cylinder as described in section 4.2
After the glue has set, the soldering operations can now commence. Instructions for the soldering are to be found in the relevant document (ref. 1 at the end of this document). The regions to solder together are the circumferential join midway along the cylinder, the longitudinal join along the length of the cylinder and the tabs from the flange to the cylinder as in FIG. 4.7.
FIG. 4.7

4.5
Preparation of Nitrogen gas purge channels
The orifice discs, which are used to evenly disperse the gas within the thermal enclosure, now need to be integrated with the gas distribution channels. To do this, the enclosed channels must be breached by cutting a slot or hole through the Cu-Kapton outer film and the closing films, as shown in FIG. 4.8.
FIG. 4.8
The copper orifice discs are then glued into position over the slots/holes taking care not to allow any glue to block the small Ø300 micron hole at the centre of the disc. The discs can then be soldered so that a good bond and sealing is ensured.
5.
GENERAL RECOMMENDATIONS
It is recommended that the roll of aluminised Kapton be transferred to a spindle supported at each end by suitable stands at approximately the same level of the working surface. This makes dispensing of the film much easier and contact with the material is therefore minimised. It also ensures the material does not come into physical contact with any objects that may transfer contaminants. The Kapton film when dispensed from the roll is in a satisfactorily clean condition and will not require further treatment. Sometimes it is recommended to prepare the
Kapton surfaces using a solution of NaOH to remove any traces of grease and grime, but experiences at RAL suggest that this is not necessary if it is dispensed straight from the roll.
However it is essential that there should be minimal handling of the Kapton side of the film (i.e. the non-aluminised side) since this is the side that will be bonded to the foam. During any handling procedure the film should be held at the extreme edges so that the areas that are actually glued to the foam are never touched; the handled areas will most likely be the areas to be trimmed off and discarded. Also, ensure that when the Kapton is not being dispensed it is kept covered at all other times to keep it protected from accidental touching etc.

For cutting the foam ensure that sufficient pressure is applied to the straight edge/rule to stop it slipping. G-clamps should be used where practicable to do this. Use a scalpel to cut the foam, running the blade along the edge of the rule; this is best carried out with several swipes, progressively cutting deeper and deeper through the foam. Ensure that the cut is perpendicular to the plane of the template or straight edge.
Using the hand held vacuum cleaner, regularly remove any traces of Airex dust that will have been produced during the cutting. Go over both sides of the sheet with the vacuum cleaner to remove any other traces of dust and debris. Remember to ensure that the working surface is also clear of any dust and debris.
The epoxy should be mixed following the manufacturer’s or supplier’s recommendations for use. The quantities should be accurately measured using precision scales. It has been found that due to the transparency of the epoxy, it is difficult to judge the coverage of the glue when applied to the foam. There are colouring agents available that can be added to the epoxy so that the glue coverage can be seen much more clearly.
Tests so far carried out at RAL on bonding Kapton® to the Airex® foam were always done by applying the epoxy to the foam and not to the Kapton®. Our experiences indicate an average glue layer thickness on the foam of as much as 0.45mm can result if the epoxy is applied with a palette knife or scraper. This tended to deliver a larger quantity of adhesive to the foam compared to the paintbrush or roller. The palette knife is by far the quickest method of applying the epoxy, but it is easy to apply over-copious amounts. It is recommended that the glue be applied using a brush as this limits the quantity of glue applied, although it is a slower process.
If the preferred or only suitable method of application turns out to be the scraper blade, then some effort will be needed to carefully inspect the surfaces for excessive build-up of glue and then removal of the excess. Regular cleaning of the blade after each scraping pass has been found to be a satisfactory way of controlling the glue thickness. Whilst it is important to try to limit the quantity of glue applied to the foam to reduce the overall mass of glue contained within the foam’s outer cavities, it is vital to ensure that there is sufficient coverage to obtain an optimum bond between film and foam.
One should bear in mind that the epoxy will slowly start to cure and its viscosity will gradually increase once the mix has been prepared. Therefore, it is important that the epoxy is applied with minimum of delay. The viscosity of the mix can be reduced if the component parts of the adhesive are kept at around 30º C prior to mixing, and then applied quickly to the parts to be bonded. Also, the cure rate will be reduced if the application to the foam is carried out at a lower room temperature of about 18º C. Another means of extending its workability, is to transfer the epoxy to a flat aluminium tray, so as to spread its volume over a larger surface area.
This is effective because the curing process is exothermic and a wide flat tray acts to dissipate any heat generated within the glue, increasing the cure time.
The quantities of epoxy applied during the manufacture of the ITE should be carefully measured and recorded during the assembly process and brought to the attention of the physicists involved on the project (S. J. Haywood) for their ‘materials used’ records.
The surfaces of the Kapton® film to be glued are always the Kapton NOT the aluminised side.

Any trapped bubbles in the Kapton (particularly those farthest from the edges of the foam) need to be punctured them using a pin, then smoothing the film to drive out the trapped air through the pin-holes formed.
During the glue curing processes the components should be left undisturbed for as long as it takes for the epoxy to set hard. If the room temperature can be increased this will advance the curing time. Leave the tray of remaining epoxy nearby to judge when the epoxy has cured.
6.
REFERENCES
Ref. 1: Investigations into possible Techniques for Joining Copper/Kapton Sheets Previously
Adhered onto Airex Foam Substrate with Araldite 2011 – Martin Gibson (02.06.05).
Ref. 2: Report into the Quantity of Adhesive Required and Various Construction Techniques to Achieve a Successful Copper/ Kapton and Kapton to Foam Interface on the ATLAS
ITE and OTE – P. Ford, M. Gibson (24.05.05).