DS450 PC frame?

[44oEX]

Ok well I just got myself a 08 DS450, and i`m looking to make it look nice.

Normaly I do the full powdercoat everthing and it turns out great. But i`ve just looked at the 21 page "pics thread" and there is note 1 picture of a DS450 with a painted or powdercoated frame. Is it that it can`t be done or whats up with that anyway?

[TNT]

I'm looking at a graph where aluminum starts to loose it's ultimate tensile strength(Ftu). At 70 degree F held for 1/2 hour it's about 3-4%, at 200F about 20%, 300F 30%. If you hold it more than 1/2 hour the graphs drops off fast.

Steel is about 3-times as dense as AL and has better heat mechanical properties.

In either case, put it through a heat cycle then under riding load is asking for trouble, moreso on AL.

You decide. ;)

[44oEX]

So how can CAN-AM powder coat the front section of the frame? It`s also aluminum.

Even the hip, it looks like silver PC, it`s not bare Al.

[blaster99]

The hip is just aluminum. I believe the rest of the frame is anodized? It sure isn't paint or power coat.

[44oEX]

Well everyone gets there swingarms PC`ed and they work just fine. A motor is al to and it gets pretty hot.

Anyway i`ll get i`ll have to stick with paint, i`ll probably be the first one.

thanks

[TNT]

I was looking at the wrong graph for staying at elevated temps, I found the right one for room temp after elevating but I left it at work....lol! I'll post it tomorrow so you all can see for yourselves. If I remember right @ 400 F 2024-T3 extruded shapes lost 25% if you kept it there 1/2 hour then cooled it to room temp. Now I think PC is only 10 mins @ 400F which may not be as bad but still 10% is too much in some areas/quads/swings.

I know a guy that keeps busy repairing PC swings.

Anodize BTW is electrical and metal gets around 100F I think, 100F you see a loss of 2-3% on the graph again depending how long in the solution.

Whats effected by the heat cycle is premature aging and fatigue life.

I'll show you the specs soon you decide, I know I won't take the chance but it may hold up fine you never know theory is theory but usually a good guide.

[ThePhantomRider]

I have seen 1 with a PC frame but it was used for product display purposes. It was PC in all black. That was about a month after the quad was announced so I believe it's long gone now. Looked real sharp but IMO alloy looks best either natural or polished.


TPR

[TNT]

Ok here we go PC 101 :)

The first graph I mentioned above is for AL @ elevated temp that stays at that temp like motors we will discuss in a sec...

This graph below is for the effect on elevated temps that are cooled to room temp such as PC. As you can see @ 400F there is about a 30% loss if held for 1/2 hour. You can see it gets worse if we hold it longer by the adjacent graphs. So PC I think is 10 mins @ 400F or so to bake the coating from a special gun and make it flow, but still you can interpolate to at least 10% loss. This graph is for 2024-t3 extruded shapes, different materials and shapes have different graphs...this is ours I beleive, but I am not a BRP engineer don't quote me, we are least close on material type.

http://i280.photobucket.com/albums/kk191/Terrylport/EffectofTempon2024JPEG.jpg

What does this mean? Well as Engineers design and do analysis they use the percentage drop as a "knock down factor"....In other words, if the frame segment is suppose to be .040 thick they will increase it by 30% to compensate for temp. When you PC however the compensation is not designed in and the part will fatigue.

Fatigue is based on cycles over time. You mentioned swing arms, one could capture cycles/time on a track and calculate when it will fail if PC'd vs as designed. Fatigue takes into account dynamic loads and the statics shown in the graph.

You asked about motors, same thing. The elevated temps are designed in as I described above, accounted for.

There is ALOT more that goes into it, I don't want to get too techincal but I think you get the idea, or I hope now. In any case, this is theory that needs to be tested or validated on an actual part and this is not an in depth analysis of DS frame segments. You could try it and see how it goes, you might be fine, if not frame parts have come down in cost over the years. :D

[44oEX]

Yeah I know what your saying. I have powder coated swingarms in the past without any problems, Heck a stock honda swingarm is PC`ed at the factory. But anyway, I can stay away for the PC, but the frame will still get a coat of paint. I have to customize this thing in some way lol.

Thanks

[TNT]

Again the HON swing temps were designed in at the factory there is no comparison. I used a brush on black rhino coating on mine, and the loovers, some frame like the skid, looks cool, holds up with little maintenance.....you could go get it done professionally too, different colors, etc....you could also anodize professionally.

I know some have PC'd the swing I'm think BCS has call them, I dunno if they had probs....I've only seen one brake due to a frozen shock linkage so it's a decent design. It is a weaker casting and the knock down factor larger than the frame.

http://i280.photobucket.com/albums/kk191/Terrylport/IMG_2739.jpg
http://i280.photobucket.com/albums/kk191/Terrylport/IMG_2733.jpg
http://i280.photobucket.com/albums/kk191/Terrylport/IMG_2734.jpg

I don't have the quad here but here looks like PA anodized the nurfs black, BRP PC'd the a-arms.

[44oEX]

Yeah I know.

It’s like I said, I just find the look to boring with the black and gray frame since everyone has it. All my bikes have been painted, until last year when I finally got the money for PC. I was hoping to finally be clear of paint and sanding. But I guess not haha. I’ll just have to get the sand paper and spay gun back out and paint it.

Normally I do pretty much every part. I’ll still get the nerfs and bumper and stuff like that PC`ed to save on the sanding, And just spray the frame and swinger (it will save me the trouble of getting the front bearings out for PC).

From what I’m seeing on the net, I’ll pretty much be one of the first DS to get a colored frame.

I’ll post pictures in December when I’m done. Need to have it ready for when the snow fly’s.

[TNT]

I didn't mean to scare you or anyone else away from PC. One of the criteria Engineers strive for is a "positive margin", meaning over designed, there is a "pad up", thicker than need be in some cases, maybe like the DS swing arm and most frame members. There is a balancing act between positive margins and weight/reliability, the DS is light so the margins(additional weight) may be small.

So every frame segment on any quad has a margin of safety, knock down factors, built into the design. There are some segments on the DS for example that would show a negative margin, like the front frame segments by the arms that we seen fail in 08/09 that are not good candidates for PC/heat cycles. Most of the DS frame segments are strong and would take to some taping into the positive margins by PC. It would boil down to trial and error and be very specific to the part/quad/rider.

That is the reason you see people try PC, heat AL/Steel to high temps and do fine, others don't last because they don't understand the structural margins.

Replacing Al frame segments with permanent fasteners/rivets is not ideal and can lead to other issues. Someone recently gave me a BRP bulletin on this I will thread soon.

[44oEX]

Yeah I know all about the safety factors that are built into...well everything.

I have broken my honda frame before (form a couple years of MX) So I guess why take the chance right, I`ll just spray it like I have done in the past.

Thanks for the info.

[slainwarrior]

you cure pc at around 400F for around 20 mins i personally wouldnt do it

[TNT]

Originally posted by 44oEX
Yeah I know all about the safety factors that are built into...well everything.
Thanks for the info.

Well good then do you know if the margins are based on limit or ultimate load on a quad? Also who determines the margin and what is the min value?

[scotturban]

dont mean to butt in, but I have the kfx450 will aluminum frame and have seen many of them with powdercoated frame, I was going to probably do mine this winter along with some of my brothers DS's frame, Will that screw us over? we race mX and they take some good hits,

[44oEX]

Originally posted by TNT
Well good then do you know if the margins are based on limit or ultimate load on a quad? Also who determines the margin and what is the min value?


No I meant just knowing about safety factors in general, not for this specific frame. The safety factors would depend on the engineer that designed it. And like you said, do you want it strong or light weight, it`s a compremise. Now mather how strong they put them, people will still find ways to break them. Will PC really make the break faster, I really don`t know. it`s hard to say.

But it`s like I said, i`ll probably end up just spraying it, just to be safe.

Should probably do the same on the KFX

[TNT]

So lets see if I can explain structural design without getting too complicated. I don't mean to make a mound out of a mole hill with this PC question, but since we have gone this far lets finish it. This thread is getting some attention, those interested read on……

It starts with coupon testing small samples of the material to see where it "yields" begins to fail or fails to establish "allowables" of the material to design to. Say 2024 T-3 extruded shapes in the DS case, in a test fixture that puts it in tension(pulling apart), FTY(Force Tensile Yield). There is also a compression coupon test of the material or FCY(Force Compression Yield). These two values, tension and compression yeild strengths of material, determine static "limit" loads. "Ultimate" FTU/FCU tension/compression strength is where the part fails and is usually 150% of limit load . Margin of Safety is (allowable divided by yield -1) and must be positive as determined by SAE(Society of Auto Engineers), there stamp of approval is on quads sold in America and Factories must adhere to their regulations.

These loads are in KSI, 1000's of pounds for major structure, and determine the geometry of the design/frame. Major structure is put through bench test after the design that take it to limit load and ultimate failure and validate the analysis/margins, static computer models, etc….

There is also dynamic/cyclic loading, meaning as the result of a MX/XC track, that is completely different than static loads. They are more difficult to model on the computer than static loads. Often factories will use data from previous or simular design to do preliminary anaylsis then later validate by prototype testing. Stress/Strain gages and test on prototype quad(s) determine the loads and validate the static loads/margins.

Even after all is said and done, negative margins can occur over time on certain parts of the quad based on the wrong loads and test data, wear, etc.... As I said above, heat cycles are considered in the design process above and built into the design. Alter it you run the risk of reducing the strength of the original design.

So the thing to do on any quad, DS, kawi, Hon, Suk is know the structure before you put it through a heat cycle. If it's a known failing part may not be a good idea. Casting's like swings are usually not good canidates unless they are large and not failing. Again a good design and strong positive margin can over come a 400F heat cycle for 20 mins that is not designed in.

Good luck!

[jcs003]

heat and AL do not mix in structrual applications. even alloyed it still has a low modulus of elatisity. it will drop into its plastic stage without warning. although, they have some treating methods out there that massivly improve its properties. but, best solution is to keep the heat away.

my suggestion would be to polish the frame members.

[florentino]

now what about anodice or whet ever you call that.

how whould that work.

also heres a pic of my yfz after one year the frame is not pc. its ceramic paint and it works just as good. yes it holds real good even on the bead locks. its all in the prep work. i may do the same to the can am.

[florentino]

one more off the bare frame

[joeyds450x]

i pc'd mine n have had no problems heres some pics..

[joeyds450x]

the swingarm and hubs

[joeyds450x]

side view....