Engine Plate Failure

[lyrad]

I've been reading some of the posts about cracking FLM engine plates and thinking "never going to happen to my stock 3mm HPI XL plate". Well performing routine maintenance on my savy, noticed my plate has cracked too!

Any suggestions on an aftermarket plate or just suck it up and spend $14 for an HPI plate since they all eventually crack anyway?

 

[frddyj]

did you have washers on the mount bolts? doesnt look like you did.

 

[lyrad]

did you have washers on the mount bolts? doesnt look like you did.

So from everyone's experience, straight out of the box from HPI, a person should remove the cap screws and add washers to them?

That's a poor design by HPI if this is the case. :crying:

 

[AllanQ]

How long have you had this piece? If you recently purchased it, HPI may warranty it, but no promises. these savages are tough as nails, but like everything else, they are not indestructable. IMO, you do not gain anything with washers under the cap heads but it also doesn't hurt to have them. To crack a motor plate like that, I would guess the you launched your truck a few times, and had some pretty hard landings.. which is the only way to have fun with these things . Stay with the stock plates, I have trashed aftermarket plates as well as the stock plates.

 

[Purenitro]

Someone should make a sticky about adding washers, although my buddy tried it and still cracked plates like they were made of glass.

Engine plates crack due to a downward force either from landing a big air and having the force of the engine constantly impacting the plate OR from landing upside down. Either way the force comes from the top, washers will not help this. Washers are still a good idea so the cap head of the screw doesn't mar the surface of the plate, eventually they will "seat" themselves into the plate so if you decide to change gearing it becomes very difficult to get a good mesh as the screws want to just slide into the original "worn in" spots on the plate.

 

[xll-SavageX-llx]

So from everyone's experience, straight out of the box from HPI, a person should remove the cap screws and add washers to them?

That's a poor design by HPI if this is the case. :crying:

You should check it over either way.
Right out of the box, put blue loctite on motor mount screws. Check over the truck and inspect it.

 

[frddyj]

So from everyone's experience, straight out of the box from HPI, a person should remove the cap screws and add washers to them?

That's a poor design by HPI if this is the case. :crying:

yep. and i always preferred the hellfire conical washers and the bolt that fits right in it. http://http://cgi.ebay.com/HPI-Z845-Cone-Washers-3x10x3-5mm-Purple-6-HELLFIRE-New-/270634625678?pt=Radio_Control_Parts_Accessories&hash=item3f0314aa8e#ht_2023wt_702
the larger surface area that the washer covers is going to distribute the force and less stress on the plate.

gotta remember that an r/c car (even sold as a rtr) is a 'model' and will need maintenance after nearly every run and before you even run it you should go through it as screws can be loose, no loctite, diffs not shimmed, etc.

 

[SwampDawg]

interesting read,
i have 2 Savys both originating from the first S25 models and still haven't cracked//broken the stock plate? wonder if this is a material defect??

 

[frddyj]

interesting read,
i have 2 Savys both originating from the first S25 models and still haven't cracked//broken the stock plate? wonder if this is a material defect??

good question, i never broke a stock or flm either. wondering if the screws coulda loosened and caused some play in there also :dunno:

 

[SwampDawg]

i honestly feel these new plates are of a different grade alloy?

could do some research, maybe even a POLL to see who broke what??

Stock:
s25 plate
x/xl plate
flm
...soforth, id bet the results would come out of the woodwork?

 

[lyrad]

Good thoughts and suggestions here...

yep. and i always preferred the hellfire conical washers and the bolt that fits right in it. http://http://cgi.ebay.com/HPI-Z845-Cone-Washers-3x10x3-5mm-Purple-6-HELLFIRE-New-/270634625678?pt=Radio_Control_Parts_Accessories&hash=item3f0314aa8e#ht_2023wt_702
the larger surface area that the washer covers is going to distribute the force and less stress on the plate.

I would consider these cone washers but my only concern is due to the spread of the contact surface could cause the engine mount to slip. The screws would have to be in a little tighter? I change tires and re-gear accordingly, so engine mount is re-adjusted which definitely seats the cap screws in more than one spot on the plate. You can see the marring in the slot of the plate which makes adjustments difficult. The cone washers would solve this. I'm going to try this.

Engine plates crack due to a downward force either from landing a big air and having the force of the engine constantly impacting the plate OR from landing upside down.

Yup guilty of jumping, but big air, not sure what your definition is of that and I agree that it's the downward force off the engine on the plate. The crack is just off to the edge of the cap screw and on the edge of the engine mount. I think the plate is flexing (folding) at that pressure point after each jump. The cutsie little triangular holes in the middle of the plate shouldn't be there. The more material at that point would possibly provide a more structual sound plate.

How long have you had this piece? If you recently purchased it, HPI may warranty it, but no promises. these savages are tough as nails, but like everything else, they are not indestructable. IMO, you do not gain anything with washers under the cap heads but it also doesn't hurt to have them. To crack a motor plate like that, I would guess the you launched your truck a few times, and had some pretty hard landings.. which is the only way to have fun with these things . Stay with the stock plates, I have trashed aftermarket plates as well as the stock plates.

Good idea, I will call HPI Service on Monday to see what they can do. The truck was bought new in early October last year, so 5 months. I think I might have run 12 jugs of fuel though it? So the run hours aren't huge, I don't think. The jumping was fun, have a look! :wiggle:

http://www.youtube.com/watch?v=6lURATvUJsg

I guess "You gotta pay to play"!

 

[lyrad]

So I talked to HPI on Monday, and they are sending an engine plate. They didn't comment whether the plate has an inherent defect, just to say that they've never heard of this problem before.

Since the LHS's don't have one in stock, and the HPI is going to be a while, I decided to make my own...

I made the plate without lightening holes, and the thickness under the engine mount 4mm over the stock 3mm.

In order to shave some weight, I shamelessly carved the XL logo on the bottom side and thinned out the plating to 2.5mm at the tranny end. The final result is it weighs 59 grams, 14 grams heavier than the stock 3mm plate.

Took Fred's advice, had to go with 4mm x 12mm engine mount cap screws over the stock 4mm x 8mm to compensate for the thicker plate and the cone washers on the bottom side.

We'll see how long this one lasts.

 

[BIGDAN89]

nice plate man maybe you could sell them if theres a market for them anymore lol and maybe the harsh cold condtions of playing in the snow and cold also affected how the plate coulda cracked

 

[JoeGuam]

Just about every engine plate has broke on me, except the new HPI plate.

 

[frddyj]

I would consider these cone washers but my only concern is due to the spread of the contact surface could cause the engine mount to slip. The screws would have to be in a little tighter?

don't worry about slippage; ive found with the washer on there and a good quality hex wrench (not the little 'L' one) the washer allows you to give it a good tight turn.

Since the LHS's don't have one in stock, and the HPI is going to be a while, I decided to make my own...

I just repped you for making this plate, it is awesome & I'm very impressed. with skillz like that you should look into making the alloy battery box mounts for the flux :stickpoke: very high-demand part. there is a cad drawing on here if your interested i could link you up.

nice plate man maybe you could sell them if theres a market for them anymore lol and maybe the harsh cold condtions of playing in the snow and cold also affected how the plate coulda cracked

If i didnt already have the carbon-fiber plate on my flux, i would be pm-ing you right now to buy one of these.

 

[AllanQ]

Great job making your plate and threw some reps your way. Lemme know if you decide to sell any of these, would be interested in a couple of them.

 

[frddyj]

only question i have it the ears that connect to the tranny. on my 4mm c/f plate, i had to shave the top of the ears for fitment & mesh. yours is shaved on the bottom; everything line up and spur & c/b mesh ok?

 

[Shaun]

all i can say is awsome!! i repped you for the craftmanship on the engine plate, should be putting your fabrication skills to work for you and make a bit of money on the side fabricating parts for people,great work!!!!

P.S. And robin i added your info into your first post as asked!! cheers!!!!!!!

 

[Mickey]

that is one awesome looking engine plate. what would one of us have to do to get you to make a few more of them ? + rep

 

[Purenitro]

Thanks Shaun, great looking plate as well, the only potential problem could be less gearing choices due to the engine being raised slightly. I had some plates laser cut a couple years back and ran into this problem, other then that, once again, great job.

 

[lyrad]

Thanks for the reps and comments ppl!

maybe the harsh cold condtions of playing in the snow and cold also affected how the plate coulda cracked

Thought of this too but I don't go out if it's colder than -10°C windchill. Besides, I would think the plastic parts would break first over this plate.

Just about every engine plate has broke on me, except the new HPI plate.

I would agree not having tested one of these myself. I still believe mine cracked because of the lightening holes in the middle. Leave the piece solid.

only question i have it the ears that connect to the tranny. on my 4mm c/f plate, i had to shave the top of the ears for fitment & mesh. yours is shaved on the bottom; everything line up and spur & c/b mesh ok?

the only potential problem could be less gearing choices due to the engine being raised slightly. I had some plates laser cut a couple years back and ran into this problem, other then that, once again, great job.

I can answer both your questions here. Although the main part of the plate under the engine mount is 4mm thick, the crossbars are inset into the plate to keep the top of the plate at the same frame height as the original 3mm plate. Shaving the bottom side of the ears was to reduce overall weight and ensure the stock screws would have the original amount of bite into the tranny plastic.

It took me over 3 evenings to make one of these plates. It looks bling, but the HPI HD plate mentioned above is only $46 at Tower Hobbies and definitely cheaper than I could make and sell it for. I'm sure, as JoaGuam mentioned above, it's solid and heavy duty.

I should run it for a few tanks first and let you know how it holds up first before we can call this a solution.

 

[lyrad]

I thought I would just give an update. There was suggestion that I get in touch with HPI, so I did. Let me just say up front that HPI Service is top notch. These people really stand behind their stuff!

I emailed them about the engine plate to asked the question if this was a common problem with the plate cracking around the mounting holes and their recommendation as a next course of action.

They replied by asking for some pictures of the plate which I then forwarded back to them with my opinion on the possible reason for the cracking.

At the end, they just tossed a new one in the mail to me and I got it yesterday.:rock1:

Thanks HPI, and I'm so glad I own one of the most popular and best supported trucks on the market.

 

[frddyj]

I thought I would just give an update. There was suggestion that I get in touch with HPI, so I did. Let me just say up front that HPI Service is top notch. These people really stand behind their stuff!

I emailed them about the engine plate to asked the question if this was a common problem with the plate cracking around the mounting holes and their recommendation as a next course of action.

They replied by asking for some pictures of the plate which I then forwarded back to them with my opinion on the possible reason for the cracking.

At the end, they just tossed a new one in the mail to me and I got it yesterday.:rock1:

Thanks HPI, and I'm so glad I own one of the most popular and best supported trucks on the market.

glad hpi hooked you up, but they shoulda contracted you to make all the motor plates for the savage line while they had you on the phone.

can you make me a set of alloy battery box mounts for my flux?