RF4Burns Build

[nelpd96]

Mate, I totally understand I am sure that everyone here is grateful for your efforts. I am going to start looking at a set of adjustable ones with a roller bearing mount as well for mine.

Cheers
Paul

[Husky]

Thats a great idea for a roller bearing as the steering is quite heavy with a sports steering wheel(small diameter) and wide grippy tyres, It also puts more stress on the steering rack. If you could minimise friction on the struts when turning by fitting a bearing on the strut it would be very helpful.
I would like to do the same on my sa struts, need to find a bearing that will work?

[rf4burns]

Yes a strut top bearing will help; and I would recommend that perhaps it would be wise to use a bearing that is already used in this application on another vehicle this will probably also require modification of the existing mount to allow solid mounting of the bearing.
Anyway back to removing the rubber from the strut top. the easiest way I have found requires some form of heating (Map torch/oxy/propane etc...) place the strut top on something solid (flame proof)

vise

apply heat to the centre (about 60 sec's was enough) The idea is not to try to melt the centre out but make the rubber release from the steel so once you have heated the centre apply pressure to the centre (push on it with another piece of steel) and it will slide out (if it does not apply more heat)

apply heat to centre

the same technique to used to remove the last piece of rubber . If you look at this photo closely you can see the centre slid out as the rubber is very smooth...except for the top a little charred (just heat the outside of the strut top - I never found it necessary to push on this )

apply heat to outside of strut top

out

then it is important the parts (centre and outside bit) where the rubber was are cleaned (sand blast if possible -it is simple to make and cheap to buy a sand blaster/cleaner to do this)

clean

Alright now I can get to refilling the void (have two options here) TBC/to be continued

[rf4burns]

Well this is it having prepared your mould depending on what you used a clamping arrangement will be required. I will be using both the silicon mould and the epoxy mould. For the silicon mould two scrap piece's of timber of suitable size were obtained (ex packing crate) and 3 hole's drilled in both pieces (lay them on top of one another so all holes line up) and one piece has a hole in the centre large enough to allow access to the strut top (think I used 75mm hole saw)

holes

the mold (epoxy one shown but silicon is same as) positioned

position mold

and strut top outer also positioned

position outer strut top

the top piece of timber is then sat in place and secured using threaded rod/bolts/clamps or what ever you have (* note this is not required for the epoxy mould but I will get to that and as not to confuse will only 1st discuss the silicon mould)

add top plate

once secured a hole needs to be drilled in the centre of the mould (ensure it is central and aligned 1st ) to allow retention of the strut centre with a bolt.

secure centre

this will be the completed mould clamp for the silicon so dismantle the clamp to allow prep of parts for pouring.
The epoxy mould does not require a clamp, a hole is drilled in the centre of the mould (to allow retention of the strut centre as same as the silicon mould) and is secured to the timber using a bolt

secure epoxy to timber

IMG01118a.jpg (14.68 KiB) Viewed 23157 times

this is the end of the clamping arrangement for the epoxy mould dismantle to allow prep for pouring /TBC

[rf4burns]

Before beginning the pour IMO it will be worth taking some time to discuss the chemicals to be used. All of these chemicals belong to the the elastomeric urethane family except the solvent (Acetone) these chemicals are high in Toluene and free isocyanide NONE OF THIS STUFF IS GOOD FOR YOU I STRONGLY SUGGEST READING THE MSDS SHEET'S. WORKING OUTSIDE IN A WELL VENTILATED AREA.NO SMOKING.WEAR GLOVES/GLASSES AND DON'T CONSUME FOOD OR BEVERAGE UNTIL YOU HAVE COMPLETED MIXING AND POURING Having said that this is a fairly straight forward process and I have used this many times
I will be using products form ERA polymers http://www.erapol.com.au/64.html if you are in W.A use Kirkside products http://www.kirkside.com.au/L77/polyurethane-elastomers/ . I have chosen CC80A this an 80 duro (hardness) cold castable 2 part epoxy.
How hard

hard scale

This is a fairly hard (when set) rubber compound (be careful with selection of hardness as to hard a material will lead to failure of other components as the rubber will not absorb the shock and will just transmit it to other components (mounts) which will fail.I think CC80M and down to about a 70 duro would work ok.
So required will be a 1.4 Kg kit of CC80A some pigment (yup you can get all different colours im staying black) and some primer (metal)

kit

*Note the primer shown here was not my 1st choice of primers! but works

[rf4burns]

Primer needs to be applied to the areas that you want the rubber to bond to (inside tappered surface and outside of centres

prime

allow to dry and reapply
apply a silicon release to molds and area's that you dont want rubber to adhere to this could be a silicon spray or grease or even a silicon based car polish

release

you now need to reassemble the clamps and on the epoxy mold attach the strut top using a small amount of silicon set the molds/clamps up level

attach top -NO CLAMP REQUIRED

level all directions

measure part A (scales required)and add pigment and mix througly and add part B (scales) and mix -try not to add air but must be mixed totally or rubber could crack

mix

pour into moulds and let harden (some urethanes can achive better hardness by baking and some will fail if baked)

pour1

pour2

[rf4burns]

Well thats it here are the result's

1

2

3

4

5

When I get the time will post a budget method if there is feed back asking for this as the ERA stuff is not that cheap total cost including Acetone/freight approx $120 (but still less than the $200+ for new ones and I can make other mounts etc... this product properly stored will keep approx 12 months) Also the budget method maybe preferred for those with friends in mining/heavy industry as the products are commonly used here .Sorry about the quality of the photo's but was photographer and mixing/pouring. RFburns

[ToranaGuy]

Nice work mate! I hope you find some time to do a few for some members on here, I know I'd probably be up for a reco set. I really should replace mine, altho I like the idea of retro-fitting a bearing, like some struts use.

Cheers

ToranaGuy

[rf4burns]

Thanks for the reply .I dont have a spare set of tops yet and am a little busy with some other projects at the moment. A bearing mod is easily possiable but not something I will be doing in the near future.

[ToranaGuy]

That's fair enough man, I know what you mean with other projects on the go, I've got a list 3 miles long, and a stash of stuff I've hoarded for a lot of them probably a mile long. Slowly getting thru them tho... lol.

Keep at it!

Cheers

ToranaGuy

[rfburns]

O.K been awhile so the Mighty boy has had a few km's on the new motor (some 4hr+ runs at full throttle a few over reving's -down hill full throttle and large tyres ) so thought I would have a look at how the bearings;big ends and mains are going with out removing the motor. So put it up on ramps drained the oil and removed the exhaust 14mm/12mm.

exhaust removal

Removed the bottom nut from the front engine mount 17mm(the one that's easy to get to from the bottom) and placed a jack under the bell housing.
Then removed the bolts from where the front engine mount where it attaches to the block on both sides of the motor 12mm used jack to lift motor as required to make this easy (only have photo of one side -the other side is where the alternator is also attached).

mount to block

also removed the small tin guard on the bottom of the bell housing near where jack is 10mm then removed all sump bolts also 10mm. Now the sump can not be lowered directly out as the distance between the front mount/cross member and bell housing prevents this .But you can rotate the sump nearly 90 degrees by jacking the motor up and rotating the rear of the sump (end near g/box)towards the front of the vehicle (bit where the headlights are ).

rotate

Once you have it rotated it still will not come out (the oil pick up stops this)but you now can get to these two 10mm bolts and remove the oil pick up and the sump will now be able to be easily removed .

remove

Now I was able to remove the bearing caps and check 'em

check

I checked them all and was happy that all was good .

shell

So put it all back together and took it out for a good thrashing

[Trav]

Thanks for the write up, handy to know.

Plus, is there anything a block of wood can't do?

[rfburns]

The only thing better then one block of wood is two and they wont get beer

[rf4burns]

Cure for sticking front brakes
Remove front wheels and place on stands

Lever the brake caliper piston back slightly (NB: if the master cyclinder is very full of brake fluid and you force the piston back you may need to lower the level of fluid in the master cyclinder (suck some out useing something) or it will overflow

Undo the two 14mm caliper mount bolts (top and bottom)

Place the caliper to the side (do not allow to hang by hose)

Rmv caliper Pin Dust Boots

[rf4burns]

Use a 19mm spanner to wiggle the caliper pin's and remove (a small amount of crc or wd40 may assist with the removal as it is uasually the grease on these pins that has gone hard that cause the dragging of the brakes)

Once the pins are removed they should be throughly cleaned (including the holes they go in) and inspected for wear (replace if necessary)

Once this is done apply a suitable high temp lube sparingly and re-assemble

NB: when fitting the caliper ensure the flats on the pins are aligned with the caliper correctly and before driving after reassembly pump the brake pedal (initially there maybe no pedal but after a couple of pumps this should return to normal)