# Routing for a pinewood derby car



## Advance The Man (Mar 1, 2011)

I currently am routing the underneath of derby cars with a small Proxxon router. My lines are not straight and would like them to be. I am getting into adult league racing and need to be able to make a consistent car. Since I'm a newbie, the site won't let me insert a weblink. If you go to youtube and search "Pinewood Derby weight pocket routing" there is a video showing a guy who has a jig set up for his router for pinewood derby. I'm uncertain if the Proxxon router is too small to set up this way (underneath). The 1/8" (3.2mm) router bit does not extend very high to make the cut through the underneath of the jig board. I typically route approximately 1/4" to 5/16" into the wood piece. One thought I had was to make an 'upside' down jig. Would place the Proxxon router on top. I've never made a jig, so layman terms would be nice. :yes4: Thanks all - there is a wealth of knowledge here. Some posts have giving me ideas of other areas to try. Thank you.


----------



## bobj3 (Jan 17, 2006)

Hi Chris

The jig in the video looks Very unsafe, I would suggest you use a template and the bit below..any time you drop stock on the bit in a floating mode you are asking for it..

Amazon.com: Milescraft 2216 1/2-Inch Bearing Guided Straight Router Bit for Mortising: Home Improvement

you can make a quick template by gluing up some 1/2" thick MDF sticks to make the sq. pocket you need..and use some tape "DSCT" to hold the parts in place.
Note once you have the pocket in place than cut the stock down to size..

YouTube - Pinewood Derby weight pocket routing

Proxxon Micro Router MOF

====



Advance The Man said:


> I currently am routing the underneath of derby cars with a small Proxxon router. My lines are not straight and would like them to be. I am getting into adult league racing and need to be able to make a consistent car. Since I'm a newbie, the site won't let me insert a weblink. If you go to youtube and search "Pinewood Derby weight pocket routing" there is a video showing a guy who has a jig set up for his router for pinewood derby. I'm uncertain if the Proxxon router is too small to set up this way (underneath). The 1/8" (3.2mm) router bit does not extend very high to make the cut through the underneath of the jig board. I typically route approximately 1/4" to 5/16" into the wood piece. One thought I had was to make an 'upside' down jig. Would place the Proxxon router on top. I've never made a jig, so layman terms would be nice. :yes4: Thanks all - there is a wealth of knowledge here. Some posts have giving me ideas of other areas to try. Thank you.


----------



## Ralph Barker (Dec 15, 2008)

There are numerous ways to approach the objective. Like Bob, I don't think I'd suggest the method shown in the video, since it appears his jig is attached to the router, and the router is just sitting on the floor, wobbling back and forth. One slip, and his fingers will be in the bit, and the workpiece will be stained blood-red. 

My preference would be a jig that holds the workpiece firmly in place, and then defines limits for the travel of the router, with the router being on top, so you can see what is being done. The task of defining the horizontal travel of the router could be done with either a template arrangement (with bearing-equipped bits or guide-bushing guides), or via stop blocks against which the router base would ride at the limits of travel. Either approach (template or stop blocks) would work. 

The template approach would add a vertical depth-of-cut issue, particularly if limited to a bearing-equipped bit, since the template would need to be thick enough to provide a surface for the bearing to ride against for the entire depth-of-cut range. 

The design of the jig, of course, depends on how you prefer to approach the cut, and how often you'll be using the jig.


----------



## Advance The Man (Mar 1, 2011)

bobj3 said:


> Hi Chris
> 
> The jig in the video looks Very unsafe, I would suggest you use a template and the bit below..any time you drop stock on the bit in a floating mode you are asking for it..
> 
> ...


The Amazon link is for 1/2", which (I don't think) fits the Proxxon's max of 1/8". What are "thick MDF sticks" and "some tape "DSCT""?

Thank you both for the comment of the youtube video. I'll take that to heart and not go that direction. This is the only use I have right now for the router. With more experience, I'll venture out. But, I'm able to make a jig for this specific use and don't plan on moving it on and off very much or at all. Are there pictures of different jigs for similar purposes? I find a picture is a 1,000 words as they say. 

Oh, and I need to hurry up and get to 10 posts so I can quote your links.


----------



## Advance The Man (Mar 1, 2011)

I'm really a novice, but I promise I learn quick. So the bearing guided router bits will 'glide' along the outside boundaries? Are these made in hobby sized bits? i.e. 1/8" or 3.2 mm?


----------



## bobj3 (Jan 17, 2006)

Hi

You may want to use a mates router for this easy job..
DSCT= Double Sided Carpet Tape
MDF = Man made wood that is very flat and easy to use..
Here's some other templates that the bit is use for..

Amazon.com: Milescraft 1213 Complete Door Mortising Kit: Home Improvement

=========



Advance The Man said:


> The Amazon link is for 1/2", which (I don't think) fits the Proxxon's max of 1/8". What are "thick MDF sticks" and "some tape "DSCT""?
> 
> Thank you both for the comment of the youtube video. I'll take that to heart and not go that direction. This is the only use I have right now for the router. With more experience, I'll venture out. But, I'm able to make a jig for this specific use and don't plan on moving it on and off very much or at all. Are there pictures of different jigs for similar purposes? I find a picture is a 1,000 words as they say.
> 
> Oh, and I need to hurry up and get to 10 posts so I can quote your links.


----------



## Ralph Barker (Dec 15, 2008)

Advance The Man said:


> I'm really a novice, but I promise I learn quick. So the bearing guided router bits will 'glide' along the outside boundaries? Are these made in hobby sized bits? i.e. 1/8" or 3.2 mm?


I've never seen bearings for 1/8"-shaft bits, but they might be out there. 

For your "hobby" router, it looks like you'll be limited to using stop blocks or the edge guide to limit the travel of the router base, and thus the area being cut. As long as you have an even surface for the router's base to ride on, you'll be OK. In some instances, for example, you might need to put a thin sheet of MDF (medium-density fiberboard) or tempered hardboard (Masonite) over the work, with a cut-out for the bit to work within.


----------



## Ralph Barker (Dec 15, 2008)

Here, as an example, is one approach to a jig for routing out your weight cavities with your Proxxon router.

The rabbets on the edges of the boards hold the workpiece down, and the blocks on top limit the travel of the router base, thus defining the dimensions of the cut-out. This approach assumes that the workpieces are going to be of consistent thickness - e.g. the same dimension as the rabbet.


----------



## bobj3 (Jan 17, 2006)

Hi

Yes you can get bearings for a 1/8" router bits from just about any bearing supply outlet..
Some router bits come with them on some round over bits and others they are in place a with Allen screw on the top of the bit...

Note ***if you have a inlay set it will do the job also with a 1/8" shank bit, it that way you don't need any bearings for the bit...but I'm not to sure if your router can take on the brass guides only you know that..  

http://www.routerworkshop.com/inlays112.html
http://www.routerworkshop.com/inlay0802.html

http://www.harborfreight.com/solid-brass-router-inlay-kit-99552.html

Making a template is easy, see below.. 

Bearings
MLCS Woodworking Adaptor Bushings and Ball Bearing Guides

Amazon.com: Dremel 692 6-Piece Router Bit Set: Home Improvement
Amazon.com: 10 pc. Mini Router Bits Set (For Dremel Tools): Home Improvement

1/8" lock collars from ACE Hardware.you will need two of them.

======
=======


----------



## Advance The Man (Mar 1, 2011)

Thank you both for the picture. I'll draw up a plan and try it.


----------



## CharleyL (Feb 28, 2009)

When I helped my son add weight to his pinewood derby car, I had him drill holes in the bottom with a Forstner bit to fit some steel washers, several 7/8" OD washers per hole.
Then I made some thin round wood inserts for him to glue into the holes. He glued the washers in place, then glued in the covers that I made, and then sand them flush. It was easy and safe for him to do and he was able to do most of it himself. When weighed the car was just under the weight limit. He won the race as well as the best of show awards with it.

I don't think a router is the best tool for this. It's so much easier and safer to do it with a drill press.

Charley


----------



## Advance The Man (Mar 1, 2011)

CharleyL said:


> When I helped my son add weight to his pinewood derby car, I had him drill holes in the bottom with a Forstner bit to fit some steel washers, several 7/8" OD washers per hole.
> Then I made some thin round wood inserts for him to glue into the holes. He glued the washers in place, then glued in the covers that I made, and then sand them flush. It was easy and safe for him to do and he was able to do most of it himself. When weighed the car was just under the weight limit. He won the race as well as the best of show awards with it.
> 
> I don't think a router is the best tool for this. It's so much easier and safer to do it with a drill press.
> ...


In the past lead has been used -- now more and more are using tungsten metal for weight. Safer than using lead and 70% more dense giving you 40% more volume based on same weight used. The key to winning is going thin by removing a lot of the wood and having as much weight to the rear of the car. My preferred tungsten is in 1/4" cubes. I have used 1" - 13/8" tungsten cylinders too. This set up I'm trying to come up with is for cubes. The cylinders are easy using a forstner bit.


----------



## MikeMa (Jul 27, 2006)

Having built MANY of these cars over the years, and realizing how small and light the wood block is, I am not sure the router is the best/safest course for this. I am thinking you would do just as well with a drill press and a couple sharp chisels to make the channel for the weights.


----------



## Advance The Man (Mar 1, 2011)

NiceG316 said:


> Having built MANY of these cars over the years, and realizing how small and light the wood block is, I am not sure the router is the best/safest course for this. I am thinking you would do just as well with a drill press and a couple sharp chisels to make the channel for the weights.


I appreciate that. I am using a Proxxon router that is truly hobby sized. It uses 1/8" shanks. What I'm doing now works and is safe and secure. I just know a more efficient way can be done. With the advice given, I plan on making a jig to make it work consistently. I agree, a larger router would be too much for the thin wood used.


----------



## Matt Fonner (Apr 18, 2011)

Advance
Did you get the answer you were looking for? I am not familiar with it, but the pictures I've seen show a square base. I have a small trim router that also has a square base. I made a jig to rout the weight pocket cavity for mine and it was pretty simple. If your interested just let me know. I'd be happy to help. 
By the way, we enjoy another common forum. I frequent PDDR and go by wood butcher. If you wanted to, you could PM me over there as well.


----------



## Slomoe (Feb 14, 2011)

I made two pine wood derby cars 30 years ago for my son’s in the Boy Scouts. It was very low and streamlined, much like a dragster. To get the weight back up to the max limit and at the correct weight, in the lowest point for stability, I machined a slot in the bottom of the car. Inserted a steel bar with holes drilled and tapped 5/16-24 and then used setscrews to get the weight correct and adjustable fore and aft. I used 6 holes if I remember right. Car was to weight at the gram. Won first and second place with the two cars. Use DGF (dry graphite film) on the axles and bake it hard, then polish it with cloth. Build up the axles so you get minimum clearance and no chatter. Turn your wheels to get them round and tapered to the center with a 1/16 flat at the center for the lowest rolling friction.


----------

