Wild Dog Adventure Riding

General => General Bike Related Banter => Topic started by: shanti on May 23, 2015, 11:51:58 am

Title: cast aliminium bash plate
Post by: shanti on May 23, 2015, 11:51:58 am
busy redoing my bashplate for my bike 07 KLR 650 , while I was at it started to look at my old plastic bashplate and was wondering the different in strength between cast aluminium and aluminium plate . I have a small sand casting foundry here in Knysna casting sculptures for artists and looking at the plastic bashplate it would be a doddle to cast one in ali using the original plastic bashplate as my hard form - it is 4.25mm thick with a 6.5mm thick border on the top . My thoughts would be to reinforce some areas by adding sculpting clay then cast . I cast sculptures which arnt subjected to the strains of a bashplate so have no idea if it would hold up - am I heading in the wrong direction here , any opinions would be appreciated
Title: Re: cast aliminium bash plate
Post by: Crab on May 23, 2015, 12:00:41 pm
The plastic plate has a good shape to work from. Nice rounded surfaces which are better than the angular cut and bend plates.
Try bending some of the aluminum that you have cast and see how it feels strength wise. 
It all depends on what is alloyed into the ali you are casting, your stock could be sourced from recycled pots and pans.
Title: Re: cast aliminium bash plate
Post by: RobC on May 23, 2015, 12:01:57 pm
No! Do not diy a cast one... :deal:
Cast aluminuim does not have the tensile strenght plate has.
The metalurgists on the group will explain why. :sip:
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 04:45:34 pm
would love to know why , I find the only brittle areas in the ali sculptures are where they have been tig welded , the KLR bash plate has formed grooves - to make the plastic form stronger , I could fill those and have thicker areas for strength ?
Title: Re: cast aliminium bash plate
Post by: RobC on May 23, 2015, 05:38:10 pm
would love to know why , I find the only brittle areas in the ali sculptures are where they have been tig welded , the KLR bash plate has formed grooves - to make the plastic form stronger , I could fill those and have thicker areas for strength ?
It has to do with the voids in a casting, forged aluminium has no voids and is much stronger than cast. Here is just one of many articles on the subject...
http://www.azom.com/article.aspx?ArticleID=1510 (http://www.azom.com/article.aspx?ArticleID=1510)
 
http://sheldonbrown.com/dp-forging.html (http://sheldonbrown.com/dp-forging.html)
"The strongest result is usually from forging. As metal cools, it forms "grains". The grains are strong, but they don't "stick" to each other perfectly. So castings may well break, and if you look at the break, it will show a bumpy "matte" surface, as it will have separated between individual grains. In metalurgists terms, it shows poor ductility."

BTW a bash plate is there to protect the cast alloy parts of a bike engine. :sip:

You also need to fit it far enough from the castings you need to protect to give the bash plate room to bend and absorb impacts without touching the engine parts in the process.
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:23:32 pm
is this not aluminium ? Casting or pressing , not sure
Title: Re: cast aliminium bash plate
Post by: Gérrard on May 23, 2015, 06:32:04 pm
Will be pressed/shaped/rolled. I had to bend and hit my AT plate back into shape regularly. If it was casted it would have snapped.
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:33:09 pm
with casting I could achieve a more rounded shape - better for deflections possibly , the bash plates I have seen and my previous one are mostly flat planes that take knocks directly - I am all for overkill  :biggrin: you should see my previous bash plate - I figure if I hit something that will break 5-6mm caast ali in a streamlined shape with enough force to break it I am deep shit already , thanks Rob for the heads up - will cast one next week and just check - got some other things to cast next week anyways
Title: Re: cast aliminium bash plate
Post by: Gérrard on May 23, 2015, 06:37:34 pm
Remember, the question is not which is the stronger, bit simply if the casted one is strong enough.

Go for it.  :thumleft:
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:39:15 pm
thanks Jupiter - seems I am going against grain here - I cant help messing with things - started last night to sculpt my angel that will be in the casting - ha ha so much for streamlined shape - her wings will help strengthen the sides - or something  :P
Title: Re: cast aliminium bash plate
Post by: Gérrard on May 23, 2015, 06:42:16 pm
O yes, something else I wanted to mention... lots of big holes to allow flexibility... like toilet paper. Ever noticed it does not break on the holes  :lol8:
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:46:52 pm
my wings will cover the major holes and I will strengthen around the smaller ones - on a more 'normal' version I would add the clay in ribs to strengthen the plate at the back - keep the front as smooth as possible , anyways obviously making it up as I go along - my previous bash plate was so strong all that could potentially happen when I collided something was my entire frame getting bent , I think a bit of built in redundancy is possibly a good thing
Title: Re: cast aliminium bash plate
Post by: SmuGS on May 23, 2015, 06:48:53 pm
Also remember a bash plates duty is to absorb and dissipate the energy from an impact while deforming, rather than transfer it directly to the engine or frame where it will cause damage..
Title: Re: cast aliminium bash plate
Post by: RobC on May 23, 2015, 06:52:37 pm
O yes, something else I wanted to mention... lots of big holes to allow flexibility... like toilet paper. Ever noticed it does not break on the holes  :lol8:
:laughing4:

My KLR's bash plate has taken dings that have loosend tooth fillings and yet hardly has dents, I am convinced that without it I would have lost a motor casing on more than one occasion. Casting will never have absorbed those blows and stayed in one peice. Fit a proper bash plate of 5mm or more plate aluminium and spend the time you would casting one out riding the bike. :sip:
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:56:01 pm
I will give it a shot next week - not holding thumbs - the ali I cast can bend somewhat ( if I de-oxidize heavily with some manganese ) as some of the arms in the sculptures have to get beaten a bit into shape if there has been a problem in the casting , a few of my forms have been around for a while so always need to be tweaked .
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:57:49 pm
O yes, something else I wanted to mention... lots of big holes to allow flexibility... like toilet paper. Ever noticed it does not break on the holes  :lol8:
:laughing4:

My KLR's bash plate has taken dings that have loosend tooth fillings and yet hardly has dents, I am convinced that without it I would have lost a motor casing on more than one occasion. Casting will never have absorbed those blows and stayed in one peice. Fit a proper bash plate of 5mm or more plate aluminium and spend the time you would casting one out riding the bike. :sip:
Rob - you have no idea how the mind of an artist works - its all good , riding and pottering in the workshop - each both essential to keep me happy
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 06:59:26 pm
there must be something to be said for deflection vs brute strength
Title: Re: cast aliminium bash plate
Post by: RobC on May 23, 2015, 07:08:35 pm
there must be something to be said for deflection vs brute strength
The diffrence between deflection and absorbing could be a 100m cliff... :sip:

Your old steel bash plate was a better option than a cast one imho as it was able to deform yet protect, a cast one will just break and probably end up piercing the very casing it was meant to protect. I understand the artistic desire to produce something beautiful... but on a DS bike brawn beats beauty every time. Do some reading on metal ductility, it convinced me.
Title: Re: cast aliminium bash plate
Post by: shanti on May 23, 2015, 07:19:17 pm
Thanks Rob - yeah doing some reading too - seems if I cast with an ali alloy I might get somewhere maybe by getting an ingot of 319.0 or 320.0 - will speak to NFS , my previous bash plate took some knocks - luckily it never brought me to a standstill otherwise i would have been over the bars - I always got knocked up ( if I am lucky  :imaposer:) knocked left or right -
Title: Re: cast aliminium bash plate
Post by: GRIM on May 24, 2015, 09:08:01 am
I say go for it  :thumleft:

If it works that's great, if not just melt it down and try something else
Title: Re: cast aliminium bash plate
Post by: Sláinte Mhaith on May 24, 2015, 09:33:14 am
No! Do not diy a cast one... :deal:
Cast aluminuim does not have the tensile strenght plate has.
The metalurgists on the group will explain why. :sip:

From the little I learned and the less I know now (not a metallurgist either by a long shot)

Casting will have a granular structure while wrought plate will have a long grained structure.
In my mind it is like gluing lots of small balls together vs gluing small sticks together. You can imagine how the sticks will be stronger.
Similar to cast iron vs steel the first will be brittle.

So my guess is a cast bash plate will most likely crack and/or break instead of deforming.

Subscribe
Title: Re: cast aliminium bash plate
Post by: Welsh on May 24, 2015, 12:30:33 pm
Pressed, fabricated or forged, if cast was strong enough you would not need a bash plate as cast cases would be strong enough. It's about elongation before it breaks.
Title: Re: cast aliminium bash plate
Post by: 2StrokeDan on May 24, 2015, 06:08:50 pm
Pressed, fabricated or forged, if cast was strong enough you would not need a bash plate as cast cases would be strong enough. It's about elongation before it breaks.

A lot of alluminium alloy frames has cast joints and steering head pieces in them, of course these are substantial in thickness.
Title: Re: cast aliminium bash plate
Post by: adamktm on May 24, 2015, 07:46:18 pm
Looking forward to seeing how it turns out!!
Title: Re: cast aliminium bash plate
Post by: shanti on May 24, 2015, 09:10:05 pm
will post some pics as it goes , I'm going with the good deflection due to rounded shape and figuring a casting of 5mm is bound to be strong enough + soft enough to absorb/protect from rocks etc , I might be wrong - how the hell do you do a strength check ?  ??? :biggrin:
Title: Re: cast aliminium bash plate
Post by: Gérrard on May 25, 2015, 08:43:08 am
will post some pics as it goes , I'm going with the good deflection due to rounded shape and figuring a casting of 5mm is bound to be strong enough + soft enough to absorb/protect from rocks etc , I might be wrong - how the hell do you do a strength check ?  ??? :biggrin:

Remember Thomas Edison, and how many times he tried, and failed, before he got the light bulb to work. If he did not try and fail we would not have had lights.

Make a rough tester and moer it with a 5pd hammer. Remember, impact that is not absorbed, is transferred somewhere else.
Title: Re: cast aliminium bash plate
Post by: lecap on May 25, 2015, 12:41:40 pm
Pressed, fabricated or forged, if cast was strong enough you would not need a bash plate as cast cases would be strong enough. It's about elongation before it breaks.

In parts like cast frame members or swing arms you have well defined forces below the yield strength of the material.

Most impacts into the sump guard cause forces well in excess of the materials yield strength. You need a material which is ductile on the one side (it absorbs energy by deforming and allows a high amount of elongation before it tears) and has good shear strength on the other side (a rock will not tear a triangle shaped hole).
I found sump guards from 4mm 5083 sheet to work very well and the sheet is readily available and quite corrosion resistant.
The putty soft architectural grade stuff is useless.

A cast bash plate will crack and shatter just like eth engine you are trying to protect.
Title: Re: cast aliminium bash plate
Post by: shanti on May 25, 2015, 01:19:38 pm
day is moving along slowly - against all logic (even my own after doing some reading and reading the replies) decided to give it a go , started my day with some urgent sculpture work ( gotta get paid for messing around ) now busy with the mould should have something cast at the end of the day to beat up with some hammers
Title: Re: cast aliminium bash plate
Post by: the_BOBNOB on May 25, 2015, 01:32:11 pm
looking good  :thumleft:

i'd like to see the end product, i think it will work

you can also add some fibreglass on the inside of the when its done - that should enforce it - in the end if it cracks it did its job - it protect your casing

if something hits it that hard that it can punch through it, through some fibreglass or rubber enforcing and then still break your casing you are screwed anyway  ;D
Title: Re: cast aliminium bash plate
Post by: Titanic on May 25, 2015, 01:38:24 pm
Shanti
Sorry for hi-jack.
When you are done with this project, why don't you have a look at the following? It might be easy for you to make us something similar.
Mirror/choke relocation bracket for the KLR
http://www.eaglemike.com/Choke-and-mirror-relocation-bracket-cmrb.htm (http://www.eaglemike.com/Choke-and-mirror-relocation-bracket-cmrb.htm)
Title: Re: cast aliminium bash plate
Post by: growweblaar on May 25, 2015, 01:47:27 pm
Interesting experiment! Subscribe.

I suspect it will shatter if you hit a rock hard, but perhaps fine otherwise...?

Have a look at this table (http://www.alteams.com/alteams-tech-centre/design-assistance/cast-aluminium-properties.html) comparing different alu alloys, magnesium, zinc & cast iron for casting. Yours would be in the S/SM column, since you're sand casting.

 :thumleft:
Title: Re: cast aliminium bash plate
Post by: shanti on May 25, 2015, 05:52:08 pm
cast the plate - last cast for the day , foundry work is hardest on Mondaze for everyone - will take a look tomorrow better - although I couldnt resist swinging a hammer at it - slight dent but cant trust that as a test for a 50km wack - still figuring deflection is this plates strength - thanks for that table - would be interesting to see what the heattr is ( heat treatment ? ) I will consider casting smaller items Titanic - I am an artist so dont have much in the way of machining in my workshop . I think for the finer items perhaps doing a lost wax casting might be better - i get good results with my bronzes with very small tolerances , can pick up a finger print in the wax if I pay attention  - of course there is always shrinkage to be accounted for - will carry on tomorrow 
Title: Re: cast aliminium bash plate
Post by: shanti on May 25, 2015, 05:55:15 pm
I did modify the original plastic bashguard by removing the lower holes and adding a strengthening to the base , those familiar with the plastic bashguard will notice the difference
Title: Re: cast aliminium bash plate
Post by: Welsh on May 25, 2015, 06:01:19 pm
Impressive... really cool  8)
Title: Re: cast aliminium bash plate
Post by: Sláinte Mhaith on May 25, 2015, 06:40:08 pm
Impressive... really cool  8)

+1
Title: Re: cast aliminium bash plate
Post by: Crab on May 25, 2015, 07:26:05 pm
Looks good so far
Title: Re: cast aliminium bash plate
Post by: Weedkiller - Adie on May 25, 2015, 08:01:50 pm
Bliksem
so leer ons elke dag iets nuut

Adie
Title: Re: cast aliminium bash plate
Post by: zacapa on May 25, 2015, 08:23:01 pm
nice thread with some counter intuitive angles. then again I bought an XR650L which is so high off the ground there is little need for a bashplate in the first place.
Title: Re: cast aliminium bash plate
Post by: capeklr on May 25, 2015, 08:51:32 pm
I like, I see it comes complete with centre stand.  >:D
Title: Re: cast aliminium bash plate
Post by: shanti on May 25, 2015, 08:54:26 pm
havn't you seen the aquaplaning farkle for the KLR yet ?
Title: Re: cast aliminium bash plate
Post by: growweblaar on May 25, 2015, 09:12:22 pm
World's first cast bashplate...?  ;)


PS: I read somewhere that bronze expands slightly just before it sets, which is why it's so good for detail on sculptures; other metals/alloys don't have this characteristic...?
Title: Re: cast aliminium bash plate
Post by: shanti on May 25, 2015, 09:26:51 pm
one of the main reasons bronze is used is because of the vast range of colours that can be patina-ed , also its ability to withstand corrosion combined with its strength , bronze shrinks as it cools (shrinkage ) never heard of it expanding or seen indications of expansion on the sculptures I have cast in bronze but you never know , the detail is picked up by the quality of the mould , ceramic shell moulds are used which have the ability to pick up very fine detail from the wax original , if the pour is good and the metal is at perfect temp with no impurities and oxygen present high detail can be achieved , other things also factor on achieving good castings - runner and riser placement - a good reservoir for the hot metal to draw from while cooling etc   - the bashplate was just cast quick quick with not too much attention paid - need to find out if I am wasting my time - good little exercise though
Title: Re: cast aliminium bash plate
Post by: zacapa on May 25, 2015, 11:16:56 pm
Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.
Title: Re: cast aliminium bash plate
Post by: Welsh on May 26, 2015, 05:49:44 am
Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.

Do the maths it is not going to happen.... 8)
Title: Re: cast aliminium bash plate
Post by: shanti on May 26, 2015, 08:49:33 am
Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.

I am not convinced as yet if this is the way forward - what began as playing around has achieved a result - it will definitely protect your engine but for how many times I am unsure about - I will finish it off and weigh it just for the exercise but I did find that it has been done before . a guy in the states cast a whole run for the TY250 - seems after repeated hits they eventually cracked .
http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/ (http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/)

Possibly this thread should be moved to Jou Ma or just Jou Moer  ;)

Title: Re: cast aliminium bash plate
Post by: Gérrard on May 26, 2015, 09:09:32 am
Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.

I am not convinced as yet if this is the way forward - what began as playing around has achieved a result - it will definitely protect your engine but for how many times I am unsure about - I will finish it off and weigh it just for the exercise but I did find that it has been done before . a guy in the states cast a whole run for the TY250 - seems after repeated hits they eventually cracked .
http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/ (http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/)

Possibly this thread should be moved to Jou Ma or just Jou Moer  ;)



Not at all. No matter what, in the end you gain knowledge  :thumleft: When I start bike build there's a lot of stuff I don't know, and with help I gain knowledge, despite fails along the way.
Title: Re: cast aliminium bash plate
Post by: Titanic on May 26, 2015, 09:39:00 am
Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.

I am not convinced as yet if this is the way forward - what began as playing around has achieved a result - it will definitely protect your engine but for how many times I am unsure about - I will finish it off and weigh it just for the exercise but I did find that it has been done before . a guy in the states cast a whole run for the TY250 - seems after repeated hits they eventually cracked .
http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/ (http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/)

Possibly this thread should be moved to Jou Ma or just Jou Moer  ;)



I'm very impressed with what you tried and achieved. Sure, according to the clever people it won't work and not a good idea etc., but at the end of the day I'll rather fit a cast bash plate than the original plastic (actually think it is more like fibreglass).
Title: Re: cast aliminium bash plate
Post by: Bensien on May 26, 2015, 09:49:05 am
Would it not be possible to anneal the finished product in order to make it less brittle? There are also additives that can be mixed into to molten metal before casting to make it more ductile. Aluminium casting technology has progressed to the extent that it is replacing forged items for critical applications in the automotive industry.
Title: Re: cast aliminium bash plate
Post by: shanti on May 26, 2015, 12:17:40 pm


Make a cast aluminium bash plate sub 0.85 kg for my XR650L that is 5mm thick and I will want your bank details to put money into your account.

I am not convinced as yet if this is the way forward - what began as playing around has achieved a result - it will definitely protect your engine but for how many times I am unsure about - I will finish it off and weigh it just for the exercise but I did find that it has been done before . a guy in the states cast a whole run for the TY250 - seems after repeated hits they eventually cracked .
http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/ (http://www.trialscentral.com/forums/topic/35787-ty-250-cast-aluminum-skid-plate-have-you-ever-saw-one/)

Possibly this thread should be moved to Jou Ma or just Jou Moer  ;)



I'm very impressed with what you tried and achieved. Sure, according to the clever people it won't work and not a good idea etc., but at the end of the day I'll rather fit a cast bash plate than the original plastic (actually think it is more like fibreglass).


thank you - from the experiment I managed to come to a few conclusions - to make an effective casting from the plastic bash plate a hard copy has to be made - this is due to the compression needed in the sand to achieve a good form to cast into - I got my hard copy now and at some point in the week when time allows give it a final grind and check for consistency in the thickness of the cast .
The bash plate appears to very strong as hitting it with a ball pein hammer is just succeeding in denting the plate slightly - its shape doesnt really allow for a flat on hit from a forward direction .

Would it not be possible to anneal the finished product in order to make it less brittle? There are also additives that can be mixed into to molten metal before casting to make it more ductile. Aluminium casting technology has progressed to the extent that it is replacing forged items for critical applications in the automotive industry.

I have been reading up on annealing the metal - it seems that it can be annealed by using a low heat - it realigns the structure and removes stress points in the casting - will pursue that a bit , also adding Magnesium apparently helps with ductile strength - once I have completed my hard copy I might take it the next step and do another casting using some more 'flexible' ali that I have with an additive of magnesium - maybe not so Jou Moer yet
Title: Re: cast aliminium bash plate
Post by: Tiger8 on May 26, 2015, 01:07:34 pm
Very interesting, to think and create outside of the box, even when told the result will be futile or undesireable, is when new discoveries usually get made. I like that you are trying anyway even against conventional wisdom and practice. If we try things for ourselves we tend to learn more than a book can teach. (Even if the book turns out to be right sometimes  ;D )

Watching your creation with interest  :thumleft:
Title: Re: cast aliminium bash plate
Post by: Jughead on May 26, 2015, 01:31:13 pm
O yes, something else I wanted to mention... lots of big holes to allow flexibility... like toilet paper. Ever noticed it does not break on the holes  :lol8:

 :imaposer:

Perforation is a rip-off!
Title: Re: cast aliminium bash plate
Post by: shanti on May 27, 2015, 02:58:54 pm
nearly at the end of this journey - I must admit there is a certain elegance to the bash plate if they can have any . I am looking into softer ali to cast from and possibly annealing it afterwards - not sure how far I am going to take this or if it is worth the journey .
The casting came out quite uniform in thickness 6mm on the flat areas , 8mm on the rim and 16mm on the thicker underside sections .
Strength wise I have hit it with various hammers and put a few dents in - there is slight bending , a more flexible ali might allow for more bending .
Weight wise - the bashplate weighs 1.52kg which is far away from my steel 7.3kg previous one

Improvements :
the top of the bashplate could be extended to make use of the engine mounting bolt points .
the stator side could be built up a bit to provide a bit more protection .
when fitting rubber could be used at the bottom between the bike frame and plate( could add a channel in the casting to accommodate this )

right then - who is for a cast aluminium helmet ?  :imaposer:
Title: Re: cast aliminium bash plate
Post by: Titanic on May 27, 2015, 03:07:00 pm
Damn I like this.
I want one!!
Title: Re: cast aliminium bash plate
Post by: the_BOBNOB on May 27, 2015, 03:08:23 pm
that is absolutely brilliant - great job  :thumleft:
Title: Re: cast aliminium bash plate
Post by: LuckyStriker on May 27, 2015, 03:15:14 pm
nearly at the end of this journey

That's very impressive. I didn't expect it to turn out as well as it did.
Looking forward to hearing how it performs
Title: Re: cast aliminium bash plate
Post by: Tiger8 on May 27, 2015, 03:28:22 pm
Great Job  :thumleft:

5.8kg's weight saving! Now go out and ride so you can tell us how it performs in the real world..............and reward yourself with a bit of helmet therapy  :biggrin:
Title: Re: cast aliminium bash plate
Post by: shanti on May 27, 2015, 03:34:30 pm
so how does one test this - its been whacked a few times with no damage other than small dents to my nicely ground shape , I dont fancy riding hard at the nearest rock to see what happens - its not so much the hard bike but the soft thing attached to it I am concerned about - it might well end up in some helmet therapy  :biggrin:
Title: Re: cast aliminium bash plate
Post by: Titanic on May 27, 2015, 04:52:02 pm
Shanti
How tricky will it be to try and cast a shroud? Those fairings on the side of the tank. They are much thinner, but there is a hell of a demand for them. I've made some from plate, but it requires extra brackets to be made to fit them.
Title: Re: cast aliminium bash plate
Post by: shanti on May 27, 2015, 05:31:17 pm
Shanti
How tricky will it be to try and cast a shroud? Those fairings on the side of the tank. They are much thinner, but there is a hell of a demand for them. I've made some from plate, but it requires extra brackets to be made to fit them.


I think they are too thin to  cast - I saw what you made with bending the ali - well done , that is the way forward - casting has some applications but I wouldnt even go there with the side shrouds - might be worthwhile making up a bending jig specific for the shrouds and having the flats cut out from a CAD drawing if you where looking at production . If you couldn't weld ali or have the equipment I guess you could pop rivet the brackets on (use some sikaflex also ) .
Title: Re: cast aliminium bash plate
Post by: SmuGS on May 27, 2015, 06:43:10 pm
Really impressed.. :thumleft:
Title: Re: cast aliminium bash plate
Post by: Bundu on May 27, 2015, 07:03:00 pm
amazing! really impressed  :thumleft:
Title: Re: cast aliminium bash plate
Post by: katana on May 28, 2015, 05:59:46 am
Very very nice  :thumleft:

From a cost perspective.  Say this bashplate was good for one decent hit and had to get replaced, what would it cost to replace?  Would a welded bashplate be more cost effective?
Title: Re: cast aliminium bash plate
Post by: Sprocketbek on May 28, 2015, 06:26:15 am
so how does one test this - its been whacked a few times with no damage other than small dents to my nicely ground shape , I dont fancy riding hard at the nearest rock to see what happens - its not so much the hard bike but the soft thing attached to it I am concerned about - it might well end up in some helmet therapy  :biggrin:

Sell them for $1000 each & wait for come-backs  :imaposer:

On a serious note, I agree with LS, also amazed at the final first product  :thumleft:
Title: Re: cast aliminium bash plate
Post by: BFG on May 28, 2015, 08:32:18 am
Well done, that's really impressive.
Give a whack with a big hammer and see what happens.
Title: Re: cast aliminium bash plate
Post by: the_BOBNOB on May 28, 2015, 08:40:39 am
Very very nice  :thumleft:

From a cost perspective.  Say this bashplate was good for one decent hit and had to get replaced, what would it cost to replace?  Would a welded bashplate be more cost effective?

what is a "good hit" ???

are we talking rocks and stuff spit up by the front wheels or are you guys doing trails riding with your bikes and actually smashing it on giants rocks and boulders ???
Title: Re: cast aliminium bash plate
Post by: shanti on May 28, 2015, 09:04:58 am
thanks for the positive replies , have been giving it many good whacks and so far its held up , the surface gets dented a bit and there is some movement in the plate - its very strong . Very busy at the moment with some dead lines which will take me till mid next week . I will revisit this project then . I can change the alloy slightly and anneal the aluminium to take it a bit more flexible and I would like  to build up the front to add some attachment points that work on the engine mounting holes .
Trying to work out a costing - here is the breakdown

R75 aluminium - its R39 per kg so having to try factor in the costs of me getting the ali ( I am in Knysna so I courier up my ali from CPT )
R340 labour for my two guys for the day - takes a couple of hours to set up the mould , a few more to pour and release from the mould and a couple more to fettle and drill out the attachment points
R130 in gas for a melt , I pour a few other things with this melt so a bit fuzzy here . I could probably do 4 in a pour accounting for the runners , risers and cup .
R20 gas for annealing
R30 for consumables - grinding , cutting , drilling
R&D no idea but could probably never recover that time cost unless I was producing lots .
R595 base costs
I guess a thumb suck with some tom for me would come out to +/- R1000 per item on the current model
If I manage to get the strength vs bendyness ? right probably a little more depending on the alloy

To be honest havn't thought that far
Title: Re: cast aliminium bash plate
Post by: shanti on May 28, 2015, 09:07:51 am
Very very nice  :thumleft:

From a cost perspective.  Say this bashplate was good for one decent hit and had to get replaced, what would it cost to replace?  Would a welded bashplate be more cost effective?

what is a "good hit" ???

are we talking rocks and stuff spit up by the front wheels or are you guys doing trails riding with your bikes and actually smashing it on giants rocks and boulders ???


Rocks and stuff kicked up from the front wheel - no problem ( have whacked the plate as hard as I can with various hammers ) - smashing into rocks at high speed - I guess there is limits mostlly determined by the survivability of the rider on top as to being able to view the damage afterwards :)
Title: Re: cast aliminium bash plate
Post by: shanti on May 28, 2015, 09:27:36 am
beginnings of version #2
Title: Re: cast aliminium bash plate
Post by: briv on May 28, 2015, 09:31:48 am
Very interesting work  :thumleft: The standard bash plate on KTM 990 is also a cast aluminium job and it stands up quite well to the elements, it has a cross pastern on the inside to strengthen it. The bottom one is the plate type replacement.
  
Title: Re: cast aliminium bash plate
Post by: katana on May 28, 2015, 10:02:34 am
thanks for the positive replies , have been giving it many good whacks and so far its held up , the surface gets dented a bit and there is some movement in the plate - its very strong . Very busy at the moment with some dead lines which will take me till mid next week . I will revisit this project then . I can change the alloy slightly and anneal the aluminium to take it a bit more flexible and I would like  to build up the front to add some attachment points that work on the engine mounting holes .
Trying to work out a costing - here is the breakdown

R75 aluminium - its R39 per kg so having to try factor in the costs of me getting the ali ( I am in Knysna so I courier up my ali from CPT )
R340 labour for my two guys for the day - takes a couple of hours to set up the mould , a few more to pour and release from the mould and a couple more to fettle and drill out the attachment points
R130 in gas for a melt , I pour a few other things with this melt so a bit fuzzy here . I could probably do 4 in a pour accounting for the runners , risers and cup .
R20 gas for annealing
R30 for consumables - grinding , cutting , drilling
R&D no idea but could probably never recover that time cost unless I was producing lots .
R595 base costs
I guess a thumb suck with some tom for me would come out to +/- R1000 per item on the current model
If I manage to get the strength vs bendyness ? right probably a little more depending on the alloy

To be honest havn't thought that far

If it absorbs enough energy to crack, R1000 is not too bad to replace it.  Well done.  A whole new way of thinking about casting.
Title: Re: cast aliminium bash plate
Post by: Warren Ellwood on May 28, 2015, 10:32:55 am
Awesome  :thumleft:.
Title: Re: cast aliminium bash plate
Post by: growweblaar on May 28, 2015, 04:21:47 pm
Bear in mind that if this one does crack after hitting a rock, it might be because you hit it many times previously with a hammer  ;D
Title: Re: cast aliminium bash plate
Post by: Straatkat on May 28, 2015, 07:02:25 pm
Maybe a good thing to try avoid is big hammers when out riding...
Shanti, I was sceptical at first, having done a fair amount of Ally casting in my life, but your bashplate looks great. In my opinion a bash plate like this will stand up to the rigours of riding off road for a very long time. How many bashplates do you see that has taken many big hits to the extent that it will break yours? My guess is not many. Well done.
Title: Re: cast aliminium bash plate
Post by: 2StrokeDan on May 28, 2015, 08:13:42 pm
Shanti, thanks for taking us through this very interesting experiment, and a seemingly very successful one, with you.

I really like what you have done.
Title: Re: cast aliminium bash plate
Post by: shanti on May 29, 2015, 08:33:26 am
a friend came round last night saw what I was doing and wants his plastic bashplate on his xt660z transformed into aluminium after seeing mine . This one is a bit more complex . I will try this with a new alloy and see what kind of result I get - I explained that this is untested and generally going against the grain - we tested mine again for strength and 'bendability ' and were quite happy to go forward .
Mine is on my bike and will stay there - must admit even though I live on farm roads and do lots of forest riding in my area I dont tend to go up many rocky stream beds etc with my 650 - I rather use a smaller bike for going that rough so not sure how much beating my bike will have in its test period .

IF this works and the metal comes out right there are quite a few bikes that could do with aluminiumizing their oem plastic bashplates 
Title: Re: cast aliminium bash plate
Post by: shanti on May 29, 2015, 08:35:48 am
1 - YZ450F
2 - KTM
3 - WR250

etc....
Title: Re: cast aliminium bash plate
Post by: Mr Zog on May 29, 2015, 08:40:08 am
Shanti, your bashplate is brilliant, and I think it will hold up just fine for the type of riding you describe you do.

Just as an aside, if you plan to make copies for other bikes on a commercial basis, just make a few "minor" changes and modifications so you don't run into "issues" about copyright or patent infringement etc...  :thumleft:
Title: Re: cast aliminium bash plate
Post by: shanti on May 29, 2015, 08:47:55 am
thanks Mr Zog - no mind for anything commercial yet . to be honest at the end of the day casting art pieces and aluminium outdoor furniture is much more economically viable , I tend to run away with my play - although I did modify the KLR bashplate even though it was more for strength reasons  it does now look 'different '
Title: Re: cast aliminium bash plate
Post by: alanB on May 29, 2015, 09:43:09 pm
Wow!

That looks great  :thumleft:

I suppose only time and testing will tell if it stands up to the rigours of actual riding.  But to me that looks very neat!

Personally I think of things like bash plates as sacrificial consumables - you want them to break instead of the bike, so there is no point in making them too strong because then they just transmit the forces onto something else that breaks instead.

Also strength usually = weight which is the enemy.

Its the same in the 4x4 world  - guys make these massively strong bumpers and things, but then bolt them directly onto the car's chassis,  So if they hit anything all that force now gets transmitted straight onto the chassis - personally I would prefer a bent bumper to a bent chassis.

My bash plate has lead a hard life.  Its constantly taking quite heavy knocks.  Here's a photo from a year or so ago, its looking a bit worse now  :P

(http://www.abolton.co.za/upload/bashplate_used.JPG)

Its saved the engine from certain damage a few times, but it is starting to develop a few cracks so its probably going to need replacement soon.

Its not pretty but it works  :thumleft:

Yours looks a lot smarter  :thumleft:




Title: Re: cast aliminium bash plate
Post by: alanB on May 30, 2015, 06:11:06 am
thanks for the positive replies , have been giving it many good whacks and so far its held up , the surface gets dented a bit and there is some movement in the plate - its very strong . Very busy at the moment with some dead lines which will take me till mid next week . I will revisit this project then . I can change the alloy slightly and anneal the aluminium to take it a bit more flexible and I would like  to build up the front to add some attachment points that work on the engine mounting holes .
Trying to work out a costing - here is the breakdown

R75 aluminium - its R39 per kg so having to try factor in the costs of me getting the ali ( I am in Knysna so I courier up my ali from CPT )
R340 labour for my two guys for the day - takes a couple of hours to set up the mould , a few more to pour and release from the mould and a couple more to fettle and drill out the attachment points
R130 in gas for a melt , I pour a few other things with this melt so a bit fuzzy here . I could probably do 4 in a pour accounting for the runners , risers and cup .
R20 gas for annealing
R30 for consumables - grinding , cutting , drilling
R&D no idea but could probably never recover that time cost unless I was producing lots .
R595 base costs
I guess a thumb suck with some tom for me would come out to +/- R1000 per item on the current model
If I manage to get the strength vs bendyness ? right probably a little more depending on the alloy

To be honest havn't thought that far

If you plan to distribute these (which I think you should be because this is a very neat product IMO) you need to factor in a retail margin as well - so that the guys selling for you make some money as well, and that must be enough to make it worth their while.  And there must also be enough in there to cover logistics as well.  People dont think of these things, but if you dont factor those costs in then the market price is set too low, your customers think its a good thing but you cant sustain the supply chain on that and the product dies.

Seen this happen over again with promising new products on the market.
Title: Re: cast aliminium bash plate
Post by: shanti on November 16, 2015, 10:07:36 am
plodding along , a friends bashplate was broken by a rock - decided to see if I could cast the more complex shape of the XT660Z - havnt done the fitting yet as sculpture work has poured in with the last minute Christmas rush . Here is the work so far 
Title: Re: cast aliminium bash plate
Post by: fcprinsloo7@gmail.com on November 16, 2015, 12:14:37 pm
Great job! I see a new line of bash plates hitting the market soon!  :dousing:to the naysayers!
Title: Re: cast aliminium bash plate
Post by: wobbler on November 16, 2015, 01:38:03 pm
I like.
A lot!
I'd love a replacement cast job for my 990 (Hint hint..)
Title: Re: cast aliminium bash plate
Post by: The Badger on November 16, 2015, 06:36:00 pm
Stylish  :thumleft: Well done.
Title: Re: cast aliminium bash plate
Post by: shanti on November 25, 2015, 09:30:03 pm
I like.
A lot!
I'd love a replacement cast job for my 990 (Hint hint..)

whats the plastic one like in terms of thickness ? - the KLR and the XT are both great for casting as the overall thickness is about 5mm and they dont have too many reinforcing bits - smooth shape
Title: Re: cast aliminium bash plate
Post by: Rufus115 on December 01, 2015, 11:41:30 am
Shanti

The HDPE KTM ones for smaller bikes are about 3-4mm thick, certainly not 5mm.

I have just read all 5 pages of this thread, and I am so impressed by what you attempt...clearly you are not only an artist in only one area .

Now that I have buttered you up with praise, I would very much like to hijack your thread just a wee bit.

I have attached a pic of a rubber/ali part that I have been contemplating getting cast in ali for a project bike. Its an intake boot off an RZ500...square one end to round other. The challenge is the round side is 26mm, I need 40mm. So what I have been pondering is getting the part drawn up in 3D CAd (which my drawing office would do for me quick quick), stretch the one end of the drawing to 40mm and then getting it 3D printed as a form to be used as in a mould to cast from. My trouble is casting is an area I have no reference in or people that know if this is feasible.....people like you :)

I would greatly value your insight into whether my idea if k@k or not.


Title: Re: cast aliminium bash plate
Post by: shanti on December 01, 2015, 01:24:04 pm
Hey Rufus - thank you , good idea , it would be interesting to see if the 3D print can burn . The logic behind this would be to get the piece printed out and then proceed as you would with a direct casting using ceramic shell . This is a process called lost wax casting - the reason I would be interested in the 'burnability' of the 3D print would be to take the print - sprue it up ( essentially adding runners and risers for the metal to flow and the air to be displaced ) , then cover with a ceramic shell then the big moment - attempt to melt out the 3D print so that you would be left with a void for the metal to run into , I have cast branches directly using this method and it has worked .
If it doesn't work then the next solution would be to make a silicone mould of your print and cast from this mould a wax version , this can be then taken to any art foundry/lost wax foundry  and cast as a normal item - obviously the mould making incurs quite a high expense as does the once off casting for the piece .
At the moment I am casting exclusively in sand but I plan next year to expand my foundry and include lost wax casting which is actually my area of expertise  I did my apprenticeship in Birmingham at an art casting foundry many many moons ago . So depending on your rush ........................
Otherwise I see you are up in JHB - In your neck of the woods these are the guys to go to - they cast a map of the world for me for Anglo American - it was too big for my little foundry - they can cast in stainless steel as well  - http://www.dswartstudio.com/ (http://www.dswartstudio.com/) - they can offer a much quicker service than me as they are a high turn around foundry + the range of metals they can cast in is quite wide .
It will be a good morning out to pop into their workshop .
Attached is an example of a direct cast branch
Title: Re: cast aliminium bash plate
Post by: Rufus115 on December 02, 2015, 08:24:43 am
Hi Shanti

Thanks v much for the extensive information. I did cover some of this in my workshop practices studies moons ago but my engineering career hasn't brought me in working touch with casting so I am a little (a little lot...) out of my comfort zone.

I will get my hands on some printed scrap and try and burn it...step 1.

Cheers for now...will be in touch  :thumleft:
Title: Re: cast aliminium bash plate
Post by: Crab on December 02, 2015, 08:49:28 am
You can do 3D wax prints too, designed for casting. Remember to allow for shrinkage as the metal cools down.
Title: Re: cast aliminium bash plate
Post by: shanti on December 02, 2015, 09:03:36 am
You can do 3D wax prints too, designed for casting. Remember to allow for shrinkage as the metal cools down.

I am so old school and out of this loop when it comes to casting - there you go Rufus - easy peasy - allow about a 1.8% reduction with the shrinkage in ALI - ie make your 3D CAD drawing 1.8% bigger . If you manage to find someone to do the wax print then most lost wax foundries casting in Ali will be able to take that into a final finish . To save money ( if its an issue ) ask to do the final fettling and grinding yourself - its PT but will save a bit

In regards to the shrinkage that has been the problem in my 1:1 copies of existing plastic bashplates - a PITA - will stick to my art castings rather unless someone is prepared to teach me the ins and outs of 3D rendering and wax printing ----------------- nah !
Title: Re: cast aliminium bash plate
Post by: Rufus115 on December 02, 2015, 10:00:05 am
Cool advice thanks

I need to make 4 of these, one for each carb. I understand that its not a cheap process, but its my dream project bike and I want to do it properly.
I don't mind doing the hand fettling myself..in fact prefer it.

Cheers again
Title: Re: cast aliminium bash plate
Post by: Weedkiller - Adie on December 02, 2015, 11:16:08 am
Hi there,
I will reply later as I need to go to a meeting.

BUTTTTT.
1. the shrinkage is not 100% linear at 1.8%  there are much more at stake like 'contractability' etc. etc. etc.
2. the part in question 'must' be heat insulating.  Keep the hot head temp away from the 'cold' carb. etc etc.
3. A 'soft' adapter will 'isolate' engine vibrations that will eat up the needle and seat etc. etc.
4. 90% of the time the alu part must be 'faced' in a machine to ensure flat mating surfaces unless it is pressure cast etc etc.
5. etc etc.

there are lots of 'easy' moulding options that will do the job.

till later

Adie

Title: Re: cast aliminium bash plate
Post by: Rufus115 on December 02, 2015, 12:38:21 pm
@ Weedkiller Adie

Now this gets interesting (I followed some of the stuff you posted under the Garage Projects section)...your points are valid and have concerned me. This has been my thinking.

The original part is a combo of ali and rubber, the ali being the cast inside the rubber on the sqr flange end, then at some point is rubber only where it terminates onto the carb. Underneath this, is the semi rubber reed block, which in my thinking would isolate some of the heat.
My intention is to fuel inject this bike (round slide Khein carbs are somewhat pricey and mucking around with jetting is not what I call fun). I am using intake bodies from an R6 with integral injectors so needle and seat wear is not a huge concern.

But I would prefer rubber, my concern is moulding rubber. I found a product called versimold on the net, a pliable heat (non pressured) curing rubber you can buy but it looks too flimsy.

....I have now turned this into a serious hijack.....new thread?
Title: Re: cast aliminium bash plate
Post by: Weedkiller - Adie on December 02, 2015, 01:57:20 pm
hi

Yes, me thinks a new thread is a must.  I will still follow this thread - not for the bashplates but for the alu casting info.

Maybe you can start with your posts edited and combined for a 'one shot up to speed' post.  >:D

Shanti
we inherited a furnace (oil burner and blower with some other parts) and are looking at some investment casting or whatever you 'foundrymen' call it.  We got/do CAD, 3D printer, moulding 'stuff' etc etc etc but no alu casting yet.  I will look at the finish and quality of clutch levers etc.

Basically we want to produce alu items without CNC milling but same finish.  dunno if it is possible.

Adie