# HDPE with no power tools?



## SlinghotME (Jan 10, 2016)

Hey Guys, looking to build my first slingshot but im wondering, would it be possible to cut HDPE (three fourths of an inch thick) easily with a coping saw? easily meaning can i cut curves and all? im planning to make MJ's mini mojo with hdpe... but i have no power tools. :banghead: anyways thank you all (im new to the forum as you can probably tell). oh and does anyone have a link to a guide for making hdpe board that is three fourths thick? (something easy though). thankyou again.


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## twang (May 10, 2015)

Try on an edge of your board to see if it cuts how you like. then you can tell.


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## SlingshotBill (May 29, 2014)

You can cut out a plastic slingshot easy with a coping saw. But if i were you id find you a piece of scrap wood do you up a practice one before you use your good stuff.

Oh watch out so you dont get the blade all twisted up.


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## SlinghotME (Jan 10, 2016)

Thanks for the info SlingshotBill, I will be looking forward to painfully cutting hdpe :drool: with a coping saw XD. Most of my wood scraps are ply wood that are splitting so much I cant use them and I dont want to buy wood... so wood isnt really a good option in my case (and also because my projects are mostly wood so I decided to twist things up a bit). We also just found HDPE sheet in our storage XD, so no need to melt buckets. Though I will still try to look for good wood scraps. Thank You.


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## leon13 (Oct 4, 2012)

Hi Volpe show'd a video where he made one just with hand tools 
Hope that helps


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## StretchandEat (Nov 11, 2015)

A coping saw cuts hdpe fine.. just make sure to keep your blade square to your material.. I made 1 and after I smoothed things out a bit with sandpaper. . I used I propane torch to make the edges slick


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## lunasling (Apr 5, 2015)

My last 2 opfs were cut with a coping saw 1/4" and 1/2" HDPE, easy just go slow and pay attention 
To how the blade follows the cutting lines keep it square.


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## Chuck Daehler (Mar 17, 2015)

Volp's vid

http://slingshotforum.com/topic/45369-making-a-hdpe-slingshot-with-no-power-tools-for-a-friend/

If you use a coping saw and for half inch or less thickness it's fine, use a course toothed blade for faster cutting.

I tried a coping saw on 1 1/8 inch thick HDPE and gave up, way way way too time consuming..used my band saw. But your sheet is thinner...it'll take time and cut a bit beyond your template line, outside it, you can rasp down the difference. That way if your cut wanders in too close or angles weirdly, if you cut outside the line you won't mess up your final result. Have extra coping blades on hand if you use a coping saw...they break if bound in the plastic.

You might just use a regular hand saw and saw it out as best you can,rough it out so to speak, using a vise of course, then rasp it using an aggressive rasp, then use a finer rasp, then 40 grit, 60, 90, 120, 220, 350 or more. That's what I do on HDPE. Wet sand only, faster, sand paper doesn't clog with plastic dust. Sit down on a chair, have a bucket of water under your work, dip the work and paper often to clean off particles. Use sanding blocks such as dowels, broom handle section, PVC pipe...whatever backings are aptly shaped for the frame.

Sand paper comes "wet" or "dry", you can't use dry sanding sand paper if you dip it in water, the abrasive will come off because the glue that holds it on will dissolve in water. Use only wet paper if you wet sand (and I hope you do).

I covered my HDPE sheet (which I call a billet) entirely with masking tape and templated the cutting line with a ball point pen. Then I cut it.

Template... make a pattern using regular typing paper, folding it in the middle for symmetry then cut it out. Use rubber cement and stick it onto a thicker piece of card stock or plastic sheet. Cut out the template and this must be an exact cut. Place the template on the masked billet and draw the design, and cut the billet. That's if you want to repeat your work someday, you'll have that template.


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## lunasling (Apr 5, 2015)

Yup thats about how i do it masking tape works great when i saw it done by Pablo (Volp)

before i just used stick glue applied it to the paper template then the hdpe stock but it tended

to pull away as you worked the saw , the above post is a great procedure!


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