Making Skins #74 - Brisbane Australia

[sailfl]

Ross

Was beer part of the release process?

[Surfcnc]

Hi Michel and Nils

Michel - A soldering iron, very interesting so thanks.

Nils got no one or anything else to blame except me and the hammer.
Next time I will use a locating pin rather than a screw and put a little grease on it.
It should just fall out with a small tap rather than repeated hammering !!

I am out of plywood at present so am working on drawing up a new deck outline and then the form to bend it over.

Regards
Ross

[Spadman]

Ross,

A bit of vaseline on the screws also helps keep the epoxy from bonding them; they should just unscrew afterwards and you can clean the holes out with a drill.

Dean.

[KenC]

I rub stuff with candle wax or spray with silicon grease when I I don't want epoxy to stick on them.

[Gerald D]

I am glad nobody suggested silicon spray on the screws - that stuff should be banned! The overspray droplets travel a long distance and mess up any surface from stuff being stuck there ever again.

[KenC]

Yes, sometimes they are too effective...

[Surfcnc]

For anyone with some CAD training (myself included) 2D drawings come "relatively" easily.
The move to 3D drafting is a bit of a different game however.

The skateboard deck shapes posed some interesting challenges to draw and also put fixing my lack of 3D drafting skills on the to do list.
Needless to say I have been drawing and redrawing, watching instructional videos and actually reading the instructions.
My weapon of choice is Sketchup a Google freebe software app.
Sketchup also accepts many Ruby pluggins that endow the software with some serious additional functionality.

So here is a nice organic shape that the software (finally ) made for me.
Mold Drawing.jpg

Once drawn in 3D the mold is easily produced on the MM.

BoardCAD - for the surfers on the MM Forum.
Me and BoardCAD have not got on very well in the past.
Finally got some gcode out of the software that could in theory shape a surfboard.

Regards
Ross

[Surfcnc]

Hi All

Thought you might like to see the toolpath the BoardCAD software generates.

BoardCAD.jpg

Regards
Ross

[baseball43v3r]

very nice sketchup drawing ross! I've been using sketchup for 4 years now, and I love the program, but its main limitation sometimes is what you were trying to achieve, organic modelling (i wouldn't say its a limitation, more of a time consuming endeavor). congrats on the progress!

2 tips if your going to use sketchup. check out the youtube videos for sketchup (which i think you've already done) and get the sketchup for dummies book. both have been invaluable resources to me over the years. good to see progress on the skateboards.

[smreish]

...I live on and near a beach my entire adult life....and I still can't surf. I need to get on that!
Thanks for sharing Ross.

[shaper]

Originally Posted by Surfcnc

Hi All

Thought you might like to see the toolpath the BoardCAD software generates.

Attachment 12527

Regards
Ross

Ross

In plan that toolpath looks good (have you got the rail cuts turned off? as it looks like it's not cutting full width). I've seen some really weird things going on in longsection at the nose and tail but haven't looked close enough at results from the latest code to know if this still exists.

Hanging to see your results when you run it.

[Surfcnc]

Hi Jed and Others

Surfboard Shaping
The config file shapebot.properties was just run on the defaults.
In this instance it does not cut the stringer hence the missing cutlines in the center but it does cut the rail plus a 20mm allowance below the apex.
The blue line in the previous pic is the blank outline so maybe that's why it appears to have not cut to the rail.

In the 2010 screen set you can see the rails pretty clearly and they "seem" OK. Famous last words.

deck on 2010 screen set.jpg

Skateboards
One of my test pilots has broken his board so luckily I have already sourced some better plywood to use.
Time permitting, tomorrow I will machine a pine vacuum form from some 90 x 35 laminated into a 1200 x 320 x 90 block.
I only have the one so here is hoping it goes smoothly.

Regards
Ross

[Surfcnc]

Roughing with a 12mm end mill.

IMG_2412.jpg
IMG_2413.jpg

The collet came loose on the finishing cut!
IMG_2415.jpg

Recut at 45 degrees and 3mm deeper with a 6mm ball mill.
This was achieved by zeroing the cutter to the table and then manually changing (increasing) the job position Z value in the Mach3 DRO by 3mm.

IMG_2417.jpg

My first ever machined vacuum form so I'm certain there is plenty of room for improvement but it was good to get a result.

Regards
Ross

[KenC]

Nice job! & it don't look like you need any sanding after the cut.

what step over % did you use?

[TechGladiator]

Ross. Very nice!... My son is already bugging me to make him a skate board on my mm and it's not completed yet!!!. In the meantime I am showing him pictures of the stuff you do on yours so he can start drooling..

[Surfcnc]

Hi Ken and Miguel

Ken the stepover was pretty small at .6 mm (10%) on a 6mm ball mill.
It did go on for quite a while though .

Miguel a new skateboard is worth major dad points in any kids eyes.

The 4mm structural ply I was trying to bend over the new vacuum form was just too stiff to conform to the tightest curve.
My serial failures are really all to do with cost as the sheet for a laminated deck with no bends is around 17 AUD.
The 1.5mm bendy ply the experts use is around 90 AUD a sheet and that makes one deck !!!

In the end the structural ply went under the MM gantry and into the vac bag to make a heavy duty replacement for my mates broken deck.
Trying to not waste any materials on my adventure so it was a reasonable compromise.
IMG_2418.jpg

Regards
Ross

[Gerald D]

Your sons only want skateboards? My son wanted 5 MechMates!

[KenC]

LOL!!!! Gerald you are killing me!!!

Ross, did you try steaming the 4mm ply? I haven't try but I'm sure marine ply can handle the heat without de-lamination.

If all else fail, make a female mould & apply brute force should do the job.

[KenC]

##PS, Gerald, is this how you remind your son about your Xmas present? LOL!!!

[ger21]

Originally Posted by Surfcnc

Recut at 45 degrees and 3mm deeper with a 6mm ball mill.
This was achieved by zeroing the cutter to the table and then manually changing (increasing) the job position Z value in the Mach3 DRO by 3mm.

Regards
Ross

You can use the Material Offset option of the 2010 Screenset to do this when zeroing.
It also works great for using the same g-code with materials of varying thickness, as you can zero off the table and have the DRO set to a specific location relative to the table. I use it all the time.

[Surfcnc]

Thanks Ger found it in the Tool Change Tab and will use it when needed.

Finished the replacement heavy duty longboard deck.
Each time I try something different, this time I used an F17 hardwood structural ply and Titebond 3 wood glue in the lamination.
The glass is a 4 x 6oz epoxy layup and that very bright lavender pigment again
Weighs in at 2.2 kg so its no sports model, more a big rig as its job is to carry a big load.

IMG_2419.jpg

IMG_2420.jpg

Regards
Ross

[Surfcnc]

Balance Board

A balance board made from the remaining hardwood ply I had from the skateboard project.

4 x 4mm plys cut on the MM, vacuumed together with Titebond 3 glue.
The rails on the underside to capture the roller were cut on the MM out of Silky Oak to match the hardwood tones.
The project is finished in a satin urethane finish for a bit of grip.

Vacuum Laminating Plys.jpg

IMG_2422.jpg

IMG_2423.jpg

Furniture Component Models

The Osborne Wood Products website has some great 3D models if anyone is interested.
You will need to provide an email address to access the downloads at http://www.osbornewood.com/
They have also contributed 139 table leg models in Google Sketchup format into the 3D warehouse website at...
http://sketchup.google.com/3dwarehou...0568&scoring=m.

I shared the last link with Aus Maddog recently, so thought others like Kobus with an indexer setup might also like it.
Note those of you without a 4th axis can machine two halves and stick them together for a perfectly functional table leg.
Here is a video of someone doing just that http://www.youtube.com/watch?v=WzaGzhH0hWE.

Regards
Ross

[TechGladiator]

Ross.

Very nice!!!. Hopefully I will be asking you for some pointers soon. I should be making dust in a few weeks.

[Kobus_Joubert]

Thank's Ross. I have downloaded LOT's and LOT's already from that site....very nice, just don't have time to cut it all. Maybe sometime I will have 24 hours to 'work' with my MM..

[Surfcnc]

The balance board has been a great hit, it's new owner has mastered the skill and takes great delight in out balancing all takers.

I recently made the mistake of buying a sheet of "ECO PLY" at my local hardware big box store.
Frankly I was amazed at the total lack of quality.
The C face veneer chipped off in a 50 square mm section and the so called structural grade 15mm ply was highly flexible and easily broken with a puny amount of weight upon it.
So that indicates both poor glue quality/distribution and poor internal quality veneers.

I used half of the sheet and a day later the remaining half was severely bowed. This product just failed, then failed, then failed again.
Nothing that ends up in the waste bin because it falls apart and breaks is "ECO".

"ECOPLY" receives my Gold Medal Product Failure Award for 2011 and a special mention in the Green Washing Spin Doctor Marketing Challenge.
It is a great honour I know, but believe me they earnt it.

Regards
Ross

[Surfcnc]

Happy New Year to all the creative people on the Mechmate forum.
Inspire me with another years worth of ideas in 2012 and I'll try to contribute something in return.

My plan for the immediate start of the new year is to run the Mechmate as a surfboard shaping machine.
Time to work on a few design and materials ideas I have kicking around in my head and try to improve my surfing in the process.

Four Point Indexed Jig to position the foam surfboard blank.
The longer post is a tail stop and the shorter posts in the centers are to spike the foam to hold it to the jig.
IMG_2516.jpg

Mock Up of How the Board is Positioned
IMG_2515.jpg

Surfboard shaping machines typically have large Z axis travel.
Using the Mechmate has involved some creative thought to fit the unshaped blanks into the MM work envelope.
After spending some time calculating and working with the software configuration file, a breakthrough came.
I established that the position of the 4 supports may be altered depending upon what side of the surfboard is being cut.
This will give the Mechmate gantry plenty of clearance to cut thicker or more curved (rockered) boards over the more typical fixed support system.

The software to both design the boards and to produce the CNC G code is Boardcad (mentioned in previous posts).
So I have my theories and once the trade stores open after the new year, it will be time to see if my ideas turn out a new surfboard or a bunch of foam pieces !!

Recently my MM has also produced some adapter rings for my dust collector system and some luggage tags.
Got to say it is a versatile tool you designed there Gerald.

Regards
Ross

[revved_up]

A month or so ago I saw some video of you crazy Aussies decked out in neon on the boards and wetsuits doing some night surfing. Looked pretty cool but the only thing I could think about was how my Salmon lures are made to glow in the dark, thinking those big white sharks might be enticed the same way. lol.

[Surfcnc]

Hi Craig

Had a few night surfs on small beach breaks (without lights) over the years and you most definately get the feeling your the bait.
One touch of a jelly fish or some seaweed gets the heat racing.
Without the lights, it is actually hard to see the unbroken swell approaching.

Some of the hell men of surfing these days, both here and in the US have taken things to new levels.
Safe - well make your own call on that one !!

Regards
Ross

[Surfcnc]

Today I mucked around with my measurement and hold down systems again for the surfboard blanks.
Got some low quality EPS blanks to cut on the machine as a test but they did not some with any 3d model files.
Consequently the blanks need to be measured and modeled in the surfboard design software.

Measuring Rocker with the Mechmate.jpg

The Mechmate is a very accurate measurement tool when used correctly.
The machine is advanced along the x axis 100mm or so at a time then the z axis reading is taken off the Mach3 DRO.
A very high tech profiling machine for measuring a surfboard rocker indeed

Thickness Calipers.jpg

Next the machine cut me a set of thickness calipers to check the thickness of the foam at various points.
Together the rocker, thickness and outline (plan shape) all make the 3d model I needed.

Oak Clamps.jpg

Broke my pine clamps so got some nicer timber and recut them with some modifications.

Here is a video of my machine cutting the clamps. The rapids are great but the plunge is still a little slow.
http://www.youtube.com/watch?v=cRvSV...w4mnOZYutXcRNJ.

Never get everything done I want to do in a day but but happy to make some headway none the less.

Regards
Ross

[AuS MaDDoG]

Very nice Ross,

Machine looks to be cutting very nicely, quality chips and dust and no smoke
Making good progress with things compared to me at the moment. But I will get there one day. In the meantime BB MechMate sits there waiting for me

Cheers
Tony.