This question didn't get any takers at rec.running, so I'll post it here in
case anyone is interested.
The running deck on my treadmill broke. Dismantling the unit I see that the
deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks for a 4x8
sheet of the stuff that I'll never use for anything else I could construct a
replacement deck from the copious amounts of 3/8" plywood and 1/2" plywood I
have on hand. I know, the thickness dimension won't be the same, but there
is definitely leeway in that. I can adjust the belt tension to compensate
for the slight increase in height.
My question/s are such. Is MDF much better for this application, a
situation where the deck will encounter someone running on it for an hour or
more every other day. That is, is plywood too flexible (too much flex will
strain the bearings for the motor)? Is MDF stronger than plywood assuming
the dimensions are the same, more durable? What would you do in this
situation, just buy the MDF and figure you'll use the rest for something
else?
This is a 3 year old treadmill, rather expensive model and cost to have the
vendor ship me a replacement board would likely be more than a new 4x8 sheet
of MDF.
I already have a prototype using a single 1/2" plywood sheet, it's
definitely too flexible to use. So now I'm wondering if laminating it with
a 3/8" would stiffen it up enough.
"Eigenvector" wrote:
> That's an interesting question, hadn't thought of it.
>
> the 3/8ths is 3 ply, the 1/2" is 5 ply
>
> Technically I don't think it's 1/2", 9/16th or similar actually.
If you can tolerate the added thickness, two (2) layers of 1/2 glued
together will provide 10 ply which would be worth a shot.
By comparison, 3/4 Birch cabinet grade has 13 plys.
Lew
"Eigenvector" <[email protected]> wrote in message
news:[email protected]...
>
> My question/s are such. Is MDF much better for this application, a
> situation where the deck will encounter someone running on it for an hour
> or more every other day. That is, is plywood too flexible (too much flex
> will strain the bearings for the motor)? Is MDF stronger than plywood
> assuming the dimensions are the same, more durable? What would you do in
> this situation, just buy the MDF and figure you'll use the rest for
> something else?
>
Likely the only reason they used MDF is that it was cheaper than plywood.
IMHO the stuff is pure junk. I'd go ahead and build up the plywood. It has
got to be better than termite puke and rat piss - you know the stuff they
call MDF.
--
-Mike-
[email protected]
Eigenvector took a can of maroon spray paint on February 24, 2008 12:35 pm
and wrote the following:
>
> "Bonehenge (B A R R Y)" <[email protected]> wrote in message
> news:[email protected]...
>> On Sat, 23 Feb 2008 15:27:07 -0800, "Eigenvector"
>> <[email protected]> wrote:
>>
>>>This question didn't get any takers at rec.running, so I'll post it here
>>>in
>>>case anyone is interested.
>>>
>>>The running deck on my treadmill broke.
>>>
>>>My question/s are such. Is MDF much better for this application, a
>>>situation where the deck will encounter someone running on it for an hour
>>>or
>>>more every other day. That is, is plywood too flexible (too much flex
>>>will
>>>strain the bearings for the motor)? Is MDF stronger than plywood
>>>assuming
>>>the dimensions are the same, more durable? What would you do in this
>>>situation, just buy the MDF and figure you'll use the rest for something
>>>else?
>>
>> My wife's Life Fitness 9100 HR uses an oak deck and an automatic
>> waxing system. The deck is similar to hardwood flooring. It has a
>> really nice feel as you walk or run.
>>
>> This is a commercial unit, top of the line when new, designed for
>> continuous use, as opposed to typical retail model. If MDF were the
>> ideal material, I think the 9100's deck would be MDF.
>>
>> I know a local guy who repairs gym equipment in commercial settings,
>> and he hooked us up with the 9100 from a local university remodel.
>
> Kinda sounds like overkill, but I bet you'll never break that deck. I'll
> bet using oak makes it wonderful to run on, very little flex, nice solid
> feel, good sound dampening.
>
> Really I think the benefit of MDF is that fact that it's smooth and CHEAP.
> But if I can pull this off with plywood then so much the better. I'm not
> quite at the point where I'll get oak planks. Smoothing it out will be a
> bear, that is certainly not plywood's strength.
How thick is it, or can it be? MDF or ply, but put some 5/8 oak t&g
flooring over top?
--
Lits Slut #9
Life would be so much easier if we could just look at the source code.
On Sat, 23 Feb 2008 15:27:07 -0800, "Eigenvector"
<[email protected]> wrote:
>This question didn't get any takers at rec.running, so I'll post it here in
>case anyone is interested.
>
>The running deck on my treadmill broke.
>
>My question/s are such. Is MDF much better for this application, a
>situation where the deck will encounter someone running on it for an hour or
>more every other day. That is, is plywood too flexible (too much flex will
>strain the bearings for the motor)? Is MDF stronger than plywood assuming
>the dimensions are the same, more durable? What would you do in this
>situation, just buy the MDF and figure you'll use the rest for something
>else?
My wife's Life Fitness 9100 HR uses an oak deck and an automatic
waxing system. The deck is similar to hardwood flooring. It has a
really nice feel as you walk or run.
This is a commercial unit, top of the line when new, designed for
continuous use, as opposed to typical retail model. If MDF were the
ideal material, I think the 9100's deck would be MDF.
I know a local guy who repairs gym equipment in commercial settings,
and he hooked us up with the 9100 from a local university remodel.
>This is a 3 year old treadmill, rather expensive model and cost to have the
>vendor ship me a replacement board would likely be more than a new 4x8 sheet
>of MDF.
Have you checked with the manufacturer about warranty? Some expensive
treadmill manufacturers warranty their products for 5 years or more.
--
Message posted via CraftKB.com
http://www.craftkb.com/Uwe/Forums.aspx/woodworking/200802/1
"toolman946 via CraftKB.com" <u40139@uwe> wrote in message
news:803183e644a1e@uwe...
> >This is a 3 year old treadmill, rather expensive model and cost to have
> >the
>>vendor ship me a replacement board would likely be more than a new 4x8
>>sheet
>>of MDF.
>
> Have you checked with the manufacturer about warranty? Some expensive
> treadmill manufacturers warranty their products for 5 years or more.
>
> --
Oh I know the vendor will supply me with a replacement, but that takes the
fun out of doing the exercise (pun intended).
"Eigenvector" <[email protected]> wrote in message
news:[email protected]...
>
> "Lee K" <[email protected]> wrote in message
> news:[email protected]...
>>
>> "Eigenvector" <[email protected]> wrote in message
>> news:[email protected]...
>>> This question didn't get any takers at rec.running, so I'll post it here
>>> in case anyone is interested.
>>>
>>> The running deck on my treadmill broke. Dismantling the unit I see that
>>> the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks
>>> for a 4x8 sheet of the stuff that I'll never use for anything else I
>>> could construct a replacement deck from the copious amounts of 3/8"
>>> plywood and 1/2" plywood I have on hand.
>>
>> Why not just glue together a couple of layers of the 3/8" plywood you
>> have so much of?
> That was my question. Indeed, why not?
>
> After thinking about what you said, I see your point, 2 3/8ths sheets is
> 3/4". Still the remaining question is whether that would be as strong
> and/or durable as 3/4 MDF.
>
The plywood has a good chance of being stronger, more durable, and lighter
than MDF. That is assuming that the plywood has had all voids repaired.
The only good attribute about MDF is that ir is very flat.
Jim
In article <[email protected]>, m44
[email protected] says...
>
> After thinking about what you said, I see your point, 2 3/8ths sheets is
> 3/4". Still the remaining question is whether that would be as strong
> and/or durable as 3/4 MDF.
>
No contest. The ply, unless it's totaly crappy quality, is going to be
considerably stronger and more durable than mdf.
-P.
--
=========================================
firstname dot lastname at gmail fullstop com
"Bonehenge (B A R R Y)" <[email protected]> wrote in message
news:[email protected]...
> On Sat, 23 Feb 2008 15:27:07 -0800, "Eigenvector"
> <[email protected]> wrote:
>
>>This question didn't get any takers at rec.running, so I'll post it here
>>in
>>case anyone is interested.
>>
>>The running deck on my treadmill broke.
>>
>>My question/s are such. Is MDF much better for this application, a
>>situation where the deck will encounter someone running on it for an hour
>>or
>>more every other day. That is, is plywood too flexible (too much flex
>>will
>>strain the bearings for the motor)? Is MDF stronger than plywood assuming
>>the dimensions are the same, more durable? What would you do in this
>>situation, just buy the MDF and figure you'll use the rest for something
>>else?
>
> My wife's Life Fitness 9100 HR uses an oak deck and an automatic
> waxing system. The deck is similar to hardwood flooring. It has a
> really nice feel as you walk or run.
>
> This is a commercial unit, top of the line when new, designed for
> continuous use, as opposed to typical retail model. If MDF were the
> ideal material, I think the 9100's deck would be MDF.
>
> I know a local guy who repairs gym equipment in commercial settings,
> and he hooked us up with the 9100 from a local university remodel.
Kinda sounds like overkill, but I bet you'll never break that deck. I'll
bet using oak makes it wonderful to run on, very little flex, nice solid
feel, good sound dampening.
Really I think the benefit of MDF is that fact that it's smooth and CHEAP.
But if I can pull this off with plywood then so much the better. I'm not
quite at the point where I'll get oak planks. Smoothing it out will be a
bear, that is certainly not plywood's strength.
"Lee K" <[email protected]> wrote in message
news:[email protected]...
>
> "Eigenvector" <[email protected]> wrote in message
> news:[email protected]...
>> This question didn't get any takers at rec.running, so I'll post it here
>> in case anyone is interested.
>>
>> The running deck on my treadmill broke. Dismantling the unit I see that
>> the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks
>> for a 4x8 sheet of the stuff that I'll never use for anything else I
>> could construct a replacement deck from the copious amounts of 3/8"
>> plywood and 1/2" plywood I have on hand.
>
> Why not just glue together a couple of layers of the 3/8" plywood you have
> so much of?
That was my question. Indeed, why not?
After thinking about what you said, I see your point, 2 3/8ths sheets is
3/4". Still the remaining question is whether that would be as strong
and/or durable as 3/4 MDF.
"Bonehenge (B A R R Y)" <[email protected]> wrote in message
news:[email protected]...
> On Sun, 24 Feb 2008 09:35:29 -0800, "Eigenvector"
> <[email protected]> wrote:
>
>>Kinda sounds like overkill, but I bet you'll never break that deck. I'll
>>bet using oak makes it wonderful to run on, very little flex, nice solid
>>feel, good sound dampening.
>
> It's got serious flex! The deck is marketed as "Flexdeck". Running
> on concrete is bad! <G>
I would have thought oak would have less flex than MDF. Granted it
undoubtedly has less than plywood of similar thickness, but I just assumed
oak would be nice and solid without noticable flex. Now I'm assuming how
thick the deck is on your treadmill, possibly it doesn't need to be thick
depending on how its designed and sprung.
I think MDF flexes, just that it has far less strength and endurance to it
>
"Eigenvector" <[email protected]> wrote in
news:[email protected]:
>
> "Lew Hodgett" <[email protected]> wrote in message
> news:[email protected]...
>>
>> "Eigenvector" wrote:
>>
>>> That's an interesting question, hadn't thought of it.
>>>
>>> the 3/8ths is 3 ply, the 1/2" is 5 ply
>>>
>>> Technically I don't think it's 1/2", 9/16th or similar actually.
>>
>>
>> If you can tolerate the added thickness, two (2) layers of 1/2 glued
>> together will provide 10 ply which would be worth a shot.
>>
>> By comparison, 3/4 Birch cabinet grade has 13 plys.
>>
>> Lew
>>
>
> I do appreciate yours and everyone's responses.
>
> For some reason I'm thinking that 2 3/8th together would be too
> flexible, but I can potentially cure that by adding an additional
> cross piece to stiffen the entire assembly. Yes I know, I'm turning
> what should be a simple matter of calling the vendor and requesting a
> replacement part into an engineering exercise - but what can I say I
> might as well have some fun figuring this out.
>
*snip*
Got a Home Depot around? They sometimes have cabinet grade 3/4" plywood
for sale for about $25 a sheet. It's usually the same as their $40
birch, but more defects are allowed (and there's many times repairs
made.) Good stuff for what you won't see anyway.
Puckdropper
--
Marching to the beat of a different drum is great... unless you're in
marching band.
To email me directly, send a message to puckdropper (at) fastmail.fm
"Eigenvector" <[email protected]> wrote in message
>
> Oh I know the vendor will supply me with a replacement, but that takes the
> fun out of doing the exercise (pun intended).
But at what price? And shipping won't be cheap. Check out the home store.
Some sell mdf in half sheets so you'd have a lot less waste. OTOH, if you
know any woodworkers in the neighborhood, they maybe jump at a deal on the
excess.
"Lew Hodgett" <[email protected]> wrote in message
news:[email protected]...
>
> "Eigenvector" wrote:
>
>> That's an interesting question, hadn't thought of it.
>>
>> the 3/8ths is 3 ply, the 1/2" is 5 ply
>>
>> Technically I don't think it's 1/2", 9/16th or similar actually.
>
>
> If you can tolerate the added thickness, two (2) layers of 1/2 glued
> together will provide 10 ply which would be worth a shot.
>
> By comparison, 3/4 Birch cabinet grade has 13 plys.
>
> Lew
>
I do appreciate yours and everyone's responses.
For some reason I'm thinking that 2 3/8th together would be too flexible,
but I can potentially cure that by adding an additional cross piece to
stiffen the entire assembly. Yes I know, I'm turning what should be a
simple matter of calling the vendor and requesting a replacement part into
an engineering exercise - but what can I say I might as well have some fun
figuring this out.
I'll try the 2 3/8ths and see what happens when I add 3 additional 2x2 cross
braces, then I'll have to sand and paint the top surface to smooth it out,
as another poster reminded me. If I can get another year out of this
treadmill I'll treat myself to a new one next year around tax time - a good
treadmill is about 1500 dollars, but it's worth every penny if you use them.
Eigenvector wrote:
> "Lee K" <[email protected]> wrote in message
> news:[email protected]...
>> "Eigenvector" <[email protected]> wrote in message
>> news:[email protected]...
>>> This question didn't get any takers at rec.running, so I'll post it here
>>> in case anyone is interested.
>>>
>>> The running deck on my treadmill broke. Dismantling the unit I see that
>>> the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks
>>> for a 4x8 sheet of the stuff that I'll never use for anything else I
>>> could construct a replacement deck from the copious amounts of 3/8"
>>> plywood and 1/2" plywood I have on hand.
>> Why not just glue together a couple of layers of the 3/8" plywood you have
>> so much of?
> That was my question. Indeed, why not?
>
> After thinking about what you said, I see your point, 2 3/8ths sheets is
> 3/4". Still the remaining question is whether that would be as strong
> and/or durable as 3/4 MDF.
>
>
My guess is that two sheets of 3/8"
glued together is much more resilient
than MDF for a lot of reasons.
--
Tanus
http://www.home.mycybernet.net/~waugh/shop/
"Eigenvector" <[email protected]> wrote in message
news:[email protected]...
>
> "Lee K" <[email protected]> wrote in message
> news:[email protected]...
>>
>> "Eigenvector" <[email protected]> wrote in message
>> news:[email protected]...
>>> This question didn't get any takers at rec.running, so I'll post it here
>>> in case anyone is interested.
>>>
>>> The running deck on my treadmill broke. Dismantling the unit I see that
>>> the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks
>>> for a 4x8 sheet of the stuff that I'll never use for anything else I
>>> could construct a replacement deck from the copious amounts of 3/8"
>>> plywood and 1/2" plywood I have on hand.
>>
>> Why not just glue together a couple of layers of the 3/8" plywood you
>> have so much of?
> That was my question. Indeed, why not?
>
> After thinking about what you said, I see your point, 2 3/8ths sheets is
> 3/4". Still the remaining question is whether that would be as strong
> and/or durable as 3/4 MDF.
It would be 3/4", assuming 3/8" ply was actually 3/8". These days, if
you're really lucky, 3/8" plywood is 5/16". And 1/2" ply measures 7/16" on
a good day. My vote would be to laminate a 3/8" and a 1/2" together. They
should add up to just about 3/4".
todd
"Eigenvector" <[email protected]> wrote in message
news:[email protected]...
> This question didn't get any takers at rec.running, so I'll post it here
> in case anyone is interested.
>
> The running deck on my treadmill broke. Dismantling the unit I see that
> the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30 bucks for
> a 4x8 sheet of the stuff that I'll never use for anything else I could
> construct a replacement deck from the copious amounts of 3/8" plywood and
> 1/2" plywood I have on hand.
Why not just glue together a couple of layers of the 3/8" plywood you have
so much of?
Isn't there some sort of laminate on the top under the belt? The top
side of the deck on my treadmill has laminate of some sort. You need
a slick, durable surface for the belt to slip on, otherwise the belt
will wear quickly. I'd be worried that plain MDF or plywood would wear
quickly, and wear the belt quickly too.
You might want to check with www.treadmilldoctor.com. (Click on Doc's
parts link) They will fabricate you a deck. Don't know whether it
will be cheaper than buying from the manufacturer. I bought a
replacement control board for my Spirit from them a few years ago, and
had them replace the bearings in the rear roller when they failed.
Their service was OK. They also sell a deck reinforcement kit you
might want to try to avoid breaking it again.
HTH,
Paul F.
"Tanus" <[email protected]> wrote in message news:[email protected]...
> Eigenvector wrote:
>> "Lee K" <[email protected]> wrote in message
>> news:[email protected]...
>>> "Eigenvector" <[email protected]> wrote in message
>>> news:[email protected]...
>>>> This question didn't get any takers at rec.running, so I'll post it
>>>> here in case anyone is interested.
>>>>
>>>> The running deck on my treadmill broke. Dismantling the unit I see
>>>> that the deck is 3/4" MDF 48" x 27" Thinking that rather than pay 30
>>>> bucks for a 4x8 sheet of the stuff that I'll never use for anything
>>>> else I could construct a replacement deck from the copious amounts of
>>>> 3/8" plywood and 1/2" plywood I have on hand.
>>> Why not just glue together a couple of layers of the 3/8" plywood you
>>> have so much of?
>> That was my question. Indeed, why not?
>>
>> After thinking about what you said, I see your point, 2 3/8ths sheets is
>> 3/4". Still the remaining question is whether that would be as strong
>> and/or durable as 3/4 MDF.
>
> My guess is that two sheets of 3/8" glued together is much more resilient
> than MDF for a lot of reasons.
>
> --
>
> Tanus
>
> http://www.home.mycybernet.net/~waugh/shop/
Not the least of which would be that 2 sheets of 3/8" plywood would be less
than 3/4" .(unless they're very old sheets of 3/8)
Max
"Lew Hodgett" <[email protected]> wrote in message
news:[email protected]...
>
> "Eigenvector" wrote:
>
>> That is, is plywood too flexible (too much flex will strain the bearings
>> for the motor)? Is MDF stronger than plywood assuming the dimensions are
>> the same, more durable?
>
> How many plys do the 3/8 & 1/2 have?
>
> Lew
>
That's an interesting question, hadn't thought of it.
the 3/8ths is 3 ply, the 1/2" is 5 ply
Technically I don't think it's 1/2", 9/16th or similar actually.
On Sun, 24 Feb 2008 09:35:29 -0800, "Eigenvector"
<[email protected]> wrote:
>Kinda sounds like overkill, but I bet you'll never break that deck. I'll
>bet using oak makes it wonderful to run on, very little flex, nice solid
>feel, good sound dampening.
It's got serious flex! The deck is marketed as "Flexdeck". Running
on concrete is bad! <G>
Hardwood floors over wood frame construction usually also flex a bit,
this is referred to as "bounce". If you're in an area that puts wood
over concrete slabs, you might not be aware of it. I always take it
for granted until I spend a week visiting Florida.
Wooden baseball bats, hockey sticks, musical instruments... all rely
on wood's flexibility to some degree.
> Smoothing it out will be a
>bear, that is certainly not plywood's strength.
Think "prefinished flooring"... It's the right thickness, smooth,
etc...