Cutting grooves in side of car where wheel edge might touch

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john-new-11
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Cutting grooves in side of car where wheel edge might touch

Post by john-new-11 » Mon Feb 25, 2019 4:05 pm

Hi. First post here.

I wanted to ask if anyone does anything like this? This is the front of the car looking down at the top.

Image

I can't decide if it makes sense, or if the edges of the wheels shouldn't be near enough to hit the car body anyway (and if they are, the least of one's worries is making these grooves...).



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whodathunkit
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Re: Cutting grooves in side of car where wheel edge might touch

Post by whodathunkit » Mon Feb 25, 2019 4:28 pm

:welcome: john -new- 11

The only thing I can think about the notches as seen in your pic where the wheel edges might rub.
Would be if you were cutting down the wheel hubs To make what most might call a rail huger
Or if you were going to cut a notch for the hub to set into as well.. to close up the width between the front wheels.

But to truly say .. this kit style.. gives the builder an option for either a right hand or left hand FDW
rail rider set up with that wheel to be inset by one 1/16'' or and 1/8".. by cutting off whats in between the notches.
Stock BSA wheels have a long enough hub to where the wheel edge sets back far enough so they don't rub the car body .
But that's if your running straight axles!





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Last edited by whodathunkit on Mon Feb 25, 2019 6:47 pm, edited 4 times in total.


What type of automobile can be spelled the same forwards & backwards?

Speedster
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Re: Cutting grooves in side of car where wheel edge might touch

Post by Speedster » Mon Feb 25, 2019 5:55 pm

Is there a story behind this particular block? Is this just a picture you have or do you actually have this block? Maybe something is being built for a Design competition.



john-new-11
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Re: Cutting grooves in side of car where wheel edge might touch

Post by john-new-11 » Mon Feb 25, 2019 6:38 pm

Thanks everyone. This is just something I saw a few people online doing, but wasn't seeing the masses do it, so I wanted to see if it was something I should consider or not (in general, not specifically related to anything else).



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whodathunkit
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Re: Cutting grooves in side of car where wheel edge might touch

Post by whodathunkit » Mon Feb 25, 2019 8:29 pm

john-new-11 wrote:
Mon Feb 25, 2019 6:38 pm
This is just something I saw a few people online doing, but wasn't seeing the masses do it,
Like you when on line i'v seen a few people doing this as well to.

One of the very first places where iv seen this notched body for front wheels was by Jobe Consulting LLC.
found on line here: http://www.pinewoodderbyphysics.com/pdf ... e%2014.pdf
#10 notched body front wheels.


What type of automobile can be spelled the same forwards & backwards?

Speedster
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Re: Cutting grooves in side of car where wheel edge might touch

Post by Speedster » Mon Feb 25, 2019 9:29 pm

OK, I understand it now. Wheel gap is normally set with the thickness of a credit car, or around .030. They are closing that gap down to almost nothing so the car can't bounce back and forth as much as if there is a .030 gap on each side of the block. The notches give the inside wheel rims some place to go so they don't drag the guide strip.



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davet
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Re: Cutting grooves in side of car where wheel edge might touch

Post by davet » Sun Jan 03, 2021 7:45 pm

Our last 3 cars all had these grooves like you made.
First, it is most needed when using BSA axles. They are smaller diameter and allow some slop in the hub. If you run a steep angle on DFW and 3 degree angle on rear axles you will get contact between wheel edge and body unless you use washers.
We run a steep angle on the DFW for steer and if that wheel hits a bad seam on the track we didn’t want it to rub the block on from edge.
Also, we run 3 degree cant on rear axles with around .008” gap. The groove ensures the wheel won’t hit the body.



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davet
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Re: Cutting grooves in side of car where wheel edge might touch

Post by davet » Sun Jan 03, 2021 7:51 pm

Our last 3 cars all had these grooves like you made.
First, it is most needed when using BSA axles. They are smaller diameter and allow some slop in the hub. If you run a steep angle on DFW and 3 degree angle on rear axles you will get contact between wheel edge and body unless you use washers.
We run a steep angle (as steep as you can make it and axle still slides smoothly through wheel) on the DFW for steer and if that wheel hits a bad seam on the track we didn’t want it to rub the block on front edge.
Also, we run 3 degree cant on rear axles with around .008” gap. The groove ensures the wheel won’t hit the body.

If you have a block that is thicker than 1/4” and can’t axles it is a MUST to groove body.
If you have a full body car take a scrap wheel and file down the inner hub so it doesn’t protrude beyond wheel edge.
Next take a strip of sandpaper and glue or tape it over the face of the wheel like when making fenders. Allow the sandpaper to extend beyond the inner wheel edge 1/8” and fold the sandpaper down over inner edge of wheel. Install wheel with an old axle and press wheel against body and twist back and forth with pressure. This will give you a nice round clearance groove for the entire top half of the wheel.



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