4rest Sk8

4rest sk8

Using an left over part of wood ("Japanese Cypress") which is caused by cutting out squared log from round wood, round wood, I made an "primitive age - style" skate board deck.

But since the wood wasn't strong enough to ride as itself, it is toughened by CNC milling and embedding epoxy and strings.

Step 1: Make Jig

•Make Jig to fix the timber to milling bed of the CNC machine

Cut out U-shape from 2cm thick plywood. It will be used to fix the timber to the CNC milling machine (This time I used "Woodpecker AP1212Y" which is Big CNC machine from China).

Step 2: Milling Pocket for Trucks

•Fix the timber to the Machine

Using the jigs made in Step1, fix the timber to the CNC machine's bed with screws. Put U-shape over both side of the timber so you can fix it without making hole on the timber itself.

•Milling Pocket for trucks

Masure dimension of tracks you want to attached to the board and mill the pocket that tracks fit it. If you choose "VENTURE SUPERLIGHT Hi" you can use same data (named "track_mount.3dm", for Rhino) for milling. In this process, the board will have pocket for trucks and 4 holes for each pockets to

fix trucks in position.

Step 3: Flip and Surfacing

• Flip the board

Unscrew the board from the bed. And then, Flip it and fix it to bet again by insert screw the holes which will be used for attaching trucks to the board in the future. If you have wood plate which is same size as the truck, you can put it to the pocket so you can fix the board horizontally.

•Flatten it by surfacing

Change the bit to surfacing tool and do surfacing to flatten the surface of the board. It's just to flatten board so you don't need to mill deeply. When I was doing it, I did 0.7mm depth surfacing.

note: WATCH OUT !!! the tool path should avoid screw fixing the material. If you want to do surfacing around holes, remove screws first and put it other side of holes of same truck pocket and then do surfacing.

Step 4: Mill Out Honeycomb

Since "Japanese Cypress" is a softwood and can be split apart along fiber direction easily, it need to be more tough so skater can ride it.

•Mill honeycomb

To make the board rugged enough to ride, I decided to embed composite which is the combination of epoxy and strings into the board's surface.

After surfacing the board, Milling honeycomb pattern channels to insert strings and epoxy into the channels.

I used Φ3mm Endmill to make 3mm width honeycomb channel.

and depth of the channels was 15mm but it should be modified depend on the wood you have.

The data for hexa path (named "millingHexa.3dm", for Rhino) can be download below...

•Remove burr

After millng, you probably get a lot of burr at everywhere you machined (if you are super pro, maybe don't). Remove these with a routery tool. Once you removed burr, then sanding surface of board with Sand paper.
I used three numbers of sand paper to make it smooth.

1. #150
2. #240
3. #400

Step 5: Prepare Composit

•Cut strings into the length it should be

When you start mixing epoxy and hardener, epoxy start curing immediately so preparing well in advance is really important.

I've planned routing of strings that each channel has at least one string. You can check my plan of routing of strings at PDF file below. And it's better to print it out so you don't need to scroll your PC with your hands attached epoxy.

And then, Cut strings into each length of the routing and number it to make sure you have all lengths of strings to put into the channels.

Step 6: Masking the Board

To avoid epoxy attach somewhere of the board, Masking the board is needed before applying epoxy.

•Laser cut masking tape

Cover a MDF board (300mm x 600mm) with masking tape (mine was 50mm width) on a MDF board (300mm x 600mm) as 5 lines horizontally. And cut out pattern (the cut sheet is available below, named "masking_parts.pdf") from it with laser cutter.

•Transfer the masking tape

When cutting is done by machine, Using a tweezer, transfer the pieces of masking tape to position so epoxy wont attache unnecessary part. Be patient.

Confirm masking tape stick to its position by pressing it well otherwise epoxy can go between masking tape and wood and finish can be dirty.

•Cover rest of board and table

Put newspapers and tape it around the board and the table to prevent working area get dirty. When you done it, it's time to mix Epoxy.

Step 7: Embed Epoxy + Strings

•Gathering all stuff on the table

Pick up all stuff you need till you finish inserting strings into the board and gather these on the table. For Eample....

• Strings
• Bottles of epoxy and hardner
• sticks and a cup for mixing epoxy
• electronic balance
• something thin so you can push string into channel (I used a flat-head screwdriver)

you should have these.

•Ventilation is crucial

IMPORTANT: Do it in well ventilated place or open window to make your space ventilated.

•Mix epoxy

Mix epoxy and hardener well to start it curing.
According to the data sheet, it just says "Mix epoxy with hardener in a proportion of 10:4". But to make curing speed slower, I mixed these in a proportion of 10:3.

•Insert strings with epoxy

After mix these well, dip first string into epoxy and let it sucks resin into its fiber.

Take a string out from cup and squeeze extra liquid softly. And then insert a string follow the routing plan you printed out. Some channels have to contain 3 or more strings so press the string to make sure it touch the bottom of channel.

Curing time doesn't wait you, get it done swiftly.

Step 8: Remove Masking Tape

•Take the tape off

When you finished inserting strings, take masking tapes off from the board carefully.

And then leave it till epoxy get cured. In my case, it took one night.

Step 9: A Bit of Adjustament

•Make head same hight as surface of the board
To make the head of "hard ware"(The bolts fixing trucks and the board) go into the surface of the board, expand holes' entry just enough the heads fit in with rotary tool.

Step 10: Finish !

•Like normal skateboard...

Attached trucks and wheels

...and actually, the strings works like grip tape so probably you don't need it.

Setting is up to you.

Step 11: Ride !!!

This board is a bit heavy, you can use it for cruising town but not for flip and vert skateboarding.
So it need modification still.

If you do it, please let me know !