Washer question

[AUPatrick]

My son and I are making a car for the Mid America Pinewood Derby and last week we ordered John's "Mid America" wheels, washers and spacers. We have never run washers before and have a couple of questions?

1) do you cut out some wood so that the washers sit flush in the body of the car? (I saw a video of Spacewalker that did this). Or, is it ok just to glue the washer directly on the side of the car?

2) Do the washers need any additional prep, such as sanding or polishing? If so, what grit sandpaper do you recommend to use?

Thanks for any input you can give.

My son is looking forward to the Mid America race and we decided to make the trip to attend in person. It's a 14.5 hour car ride from Mississippi to Omaha, so we are trying to make the best car that we can and hopefully have a good showing.

 

[5KidsRacing]

1) Washers/spacers are legal so no reason to put them into the body. You don't need to glue them to the body either, but you can.

2) I don't, but if you want to try and polish them with a plastic polish it can't hurt.

 

[speed bump]

5kid I just got back my car from the race and trying to get it ready for the next race on the 26th. Do people sand the washer with 3,000 or just plastic polish work? Also can u put telfon tuff over it ?? Just looking into something that I might not be doing. Trying different wheel prep this time to.

 

[AUPatrick]

Thanks 5kids.

I have never run the wheels reversed and don't want to mess anything up. After I ordered the Nitro "Mid America" tires, I started thinking that it might be safer to get the Cheetah's. But since we are making the long trip I figured we would take the "go big or go home" position and keep my current order

 

[5KidsRacing]

5kid I just got back my car from the race and trying to get it ready for the next race on the 26th. Do people sand the washer with 3,000 or just plastic polish work? Also can u put telfon tuff over it ?? Just looking into something that I might not be doing. Trying different wheel prep this time to.

Sanding the DFW washer can't hurt, like I said I don't... your wheel only rubs on one little spot and I figure after a couple passes that gets polished.

I don't think I would put anything on it, Delrin is already a slippery material... I don't even think anything would adhere to it very well.

 

[speed bump]

Thanks 5 kid. Working on car. I don't know about my front wheel gap. To big of gap and it wobbles when slow rolling it. I need a best track I can see that already.

 

[5KidsRacing]

Thanks 5 kid. Working on car. I don't know about my front wheel gap. To big of gap and it wobbles when slow rolling it. I need a best track I can see that already.

I like to run non-grooved axles on the DFW a lot for that reason, but you shouldn't have a problem with the DD4H axles.... some vendors axles have too wide of a groove.

 

[speed bump]

Thanks again 5 kids. I really appreciate the information. Thanks again.

 

[IAE Racing]

Thanks 5kids.

I have never run the wheels reversed and don't want to mess anything up. After I ordered the Nitro "Mid America" tires, I started thinking that it might be safer to get the Cheetah's. But since we are making the long trip I figured we would take the "go big or go home" position and keep my current order

Atta Boy!/images/boards/smilies/thumb.gif

 

[Guest]

Thanks 5kids.

I have never run the wheels reversed and don't want to mess anything up. After I ordered the Nitro "Mid America" tires, I started thinking that it might be safer to get the Cheetah's. But since we are making the long trip I figured we would take the "go big or go home" position and keep my current order

Atta Boy!/images/boards/smilies/thumb.gif

+1.
Fortune favors the brave

 

[B_Regal Racing]

Is there anyone who does not run washers?

 

[TRE]

i think everybody runs some kind of a friction plate

 

[cycrunner]

I make my own washers/spacers from Teflon rod stock on my lathe. I drill the hole in the washer to slightly press fit on the axel. I radius the side that will ride against the wheel hub and polish it to 12K, then cut it off the stock about 1/32 to 1/16th inch thick or whatever. I have also done this with graphite rod stock. No need to attach to the car body if it stays put on the axel.

 

[KGL]

I have used this product from McMaster Carr in place of washers. It is a adheisve backed Teflon sheet. Just cut it to size, punch your axle holes and stick it on the side of the car. Is it faster than delrin washers, I don't know but the adheisve back teflon is easy to use.

1

8711K91

Sheets Made with Teflon(R) PTFE, Adhesive Ready, .015" Thick, 6" X 6"

 

[HurriCrane Racing]

I ordered the Teflon sheet you mentioned but it does not have an adhesive on it. Needed to glue it on.
If I don't use washers, then I use the Teflon Tuff polish. Don't see much of a speed difference between the three methods.

 

[Mister B Racing]

I have some of that teflon sheet too. Mine does not have adhesive backing either, but the description does say the sheet comes with the adhesive backing. Most likely there is an error in the description on the McMaster Carr web site.

 

[bracketracer]

I have some of that teflon sheet too. Mine does not have adhesive backing either, but the description does say the sheet comes with the adhesive backing. Most likely there is an error in the description on the McMaster Carr web site.

The description I read said it was etched for adhesive, ie: it was ready for adhesive to be applied. One side is etched, one side is slick.

 

[Mister B Racing]

Bracket racer - you are right, my mistake. The question then becomes what is the best adhesive to use to put this on your car? I tried CA on a sample to wood but when the glue dries it seems to be brittle. Touch the teflon just wrong and it would pop right off the body.

 

[GravityX]

Is there anyone who does not run washers?

Most of my cars are washer-less at the rears, unless the wheel requires it, like running reversed wheels and I always run a washer at the DFW regardless.

 

[bracketracer]

Bracket racer - you are right, my mistake. The question then becomes what is the best adhesive to use to put this on your car? I tried CA on a sample to wood but when the glue dries it seems to be brittle. Touch the teflon just wrong and it would pop right off the body.

Man, I have the same problem when I tried gluing the washers to the body, they just pop off. I started using slide tape instead of washers and I inlaid it into the car body so it stays put.