Economical Hot knife solution

Oct 28, 2013
678
Hunter 20 Lake Monroe
Harbor Freight Hot knife.jpg






I have been busy sewing a pop top tent for our Hunter 20 and was in need of a hot knife to cut the fabric with to keep the edges from unraveling. I don't do enough to justify paying 120 for a official hot knife so after trying a few of the single element soldering iron type knives with disappointing results I decided to make my own.
I started out with a dual element soldering iron from Harbor Freight for 13.88 on sale. I then took the spare tip that was a constant diameter piece of wire and reshaped the end to for a curve about the diameter of a dime. I then took it to the anvil and hammered the curved part of the tip into a flat knife shape. You don't want the edge to be "sharp" as it will cut through the material without transferring enough heat to seal the material. You want a nice smooth rounded edge on the curved part. I filed the new edge smooth and cut the element legs to an equal length and installed the new tip in the gun.
I squeezed the trigger and gave it a try and it worked better than I even hopped it would. It seals the edges perfectly and only takes about 25 seconds to heat up. The built in light is a nice touch as well.
Here is the tip after I formed it. I had been cutting quite a bit before I took this pic and it seems to be holding up well. I think it will serve my needs very well.
Fabric cutter.jpg

Here is a sealed edge of material after cutting.
Sealed edge.jpg

It is common for some of the sealed edge to stick back to the to other side as you are cutting. I thought that was a problem till I watched a few videos and saw that was common even on the expensive hot knives. It cuts easily if it does not separate when you pull the pieces apart.

Here is our top now that it is almost done.
Front view (Large).jpg

door (Large).jpg


The dark area below the screened opening is a overlapping edge inside that I need to trim yet. The light was shining through the windows in the front which made that show up. This project really pushed the limits of not only my sewing ability but also the limits of my old machine. This was the first zipper I had ever put in and the curve turned out to be a real bear. But that paled in comparison to the problems the window material gave me. It was absolutely awful to sew till I figured out that it was sticking to the table and then the bottom of the presser foot of my machine. Once I coated both surfaces with painters tape it went much, much better.
Wish it had turned out better but it will serve the purpose nicely.

Sam
 
Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
Great tips! I love DIY tricks. Nice looking pop-up. What machine are you using?
 
Oct 28, 2013
678
Hunter 20 Lake Monroe
I got my mom's old Kenmore when she passed away. I'm sure she is rolling over in her grave watching me see all the things that I sew with it that I should not be sewing with it. I really want to upgrade to a walking foot machine but hate to spend that much on a sewing machine. Each project I do I think will be my last. I just need to come to terms with the fact that I will always be sewing something and just spend the money.

Sam
 
Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
I am currently borrowing a LSZ-1 Sailrite walking foot machine for all of my extensive projects. After using my wife's home Singer machine, the difference is astounding. Now I do everything on the Sailrite. In addition to repairing and modifying my winter cover, bimini, dodger, etc., I also hem my jeans. Home machines don't much care for hemming jeans because the material is so heavy and with lots of layers. The Sailrite is the way to go. At some point my sailing friend will want his machine back. I can see a machine purchase in my future someday. Actually the resale of the Sailrite machines is pretty close to a new one- at least the asking price is there. I suspect that you could easily sell a Sailrite for a few hundred less than you pay for it.
 
Jan 30, 2012
105
Catalina 36 Bayfield, WI
I've been trying to find a used Sailrite machine too and the one that I did find, the seller would only come down 150.00 from the price of new. Guess I'm going to have to bite the bullet too.

Glad the hear the H/F knife works for cutting canvas. Way cheaper than the one at Sailrite.
 
Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
If you watch the Sailrite sales, they periodically offer a great package for little more than the base machine. They include the hot knife and lots of very useful accessories for the machine. Some of the accessories look like a "so what", but on my projects I have used most of them. Starter packs of thread and needles too are included. Sometimes you don't realize what you need to have in equipment until you start. At least that was the case with me- I am a non-sewer, a hack. And if you don't buy their machine, do watch their video series on how to do most anything. They give the clueless some clues.
 
Oct 28, 2013
678
Hunter 20 Lake Monroe
Oh I watched their videos. But they had the ideal setup with the proper equipment, the right machine, and a large work surface. I had the wrong equipment, the too light of a machine, and a small dining room table. The perfect recipe for disaster.
At one point I was ready to stomp the cover and set it on fire but jn my haste to rip it off the table I managed to knock the candle opera that hangs over the table off the ceiling. I managed to catch it before it hit the table but then had to use one foot to keep the machine on the table. Shortly after putting it all back together and I got started sewing again I ran out of thread with just about 10 inches left to go. It was a great day...

Sam
 
Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
Bobbins always run out with 10 inches to go. Your experience is perfectly normal.
 

51RD55

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Jul 13, 2015
99
Hunter 31 Toronto
Nice job on the cover. I sewed when I was a teenager; my mom was a seamstress. Too bad I don't have her machine. A friend of mine has an industrial machine in her apartment, I'm sure that I could hire her for a decent wage to fix my bimini cover.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
I bought a Montgomery Wards machine back in the 70s. Metal case, as I recall. It would sew the six layers of hems in the corners of my projects. Then in the 2000s, I was in FL helping a friend bring his boat up from Key West. When we stopped in Ft Lauderdale, the Sailrite store had just opened and had a sale going on. I had just received my tax return, and spent it on the Zig-Zag machine. It has been a blessing, as I now never buy anything already made. And, yeah, it is great on jeans! It is like hitting the lottery: you soon will find you have alot more "friends" than you thought. I have 2 or 3 people needing some canvas work done. I plug the machine and a clock through a foot switch. The machine goes on, the clock goes on. Just so I'm not feeling "used", I like 20$ an hour (or something of equal value. A case will do). Now, if I'd just finsh up my own projects!
 
Oct 28, 2013
678
Hunter 20 Lake Monroe
I just need to bite the bullet. I did not know Sailrite had sales. I will have to check that out and catch one.
They are right up the road from us in North central Indiana but they don't allow you to stop and shop or pick anything up according to the website

Sam
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
A decade or so ago, Sailrite opened a store here in Eastport/Annapolis. It was nice to have it so close, but even though it was just a block from the Annapolis Harbor, I guess they just were not financially doable. They often have sales of 10 percent off, but often more for certain items.
 
Oct 28, 2013
678
Hunter 20 Lake Monroe
I just checked out the LS1 zig zag online. To get a usable model with bobbins and such it is 949.00. Ouch!
10% off would help but even at that it is going to be hard to justify that expense no more than I sew.

Sam
 
Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
Just so I'm not feeling "used", I like 20$ an hour (or something of equal value. A case will do).
$20/hr?!! I bill my hours out at eighteen cents per hour to all my friends. And when I figure my labor rate in my own projects, they still cost HUNDREDS of Dollars!
 
Sep 15, 2009
6,243
S2 9.2a Fairhope Al
defender sells a machine you may look at ...don't know anything about it but they sell machines
 
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Apr 26, 2015
661
S2 26 Mid On Trailer
Sign up (email address) on Sailrite's website and they will send you emails 5 days a week with all kind of specials including machines. Free shipping yesterday.

Oh yea, to the OP, nice hot knife I'm going to the garage tomorrow and pound one out before I go sailing. Need to get a few more sailing days in before it gets a 100 °.
 
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Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
[QUOTE="... I just checked out the LS1 zig zag online. To get a usable model with bobbins and such it is 949.00. Ouch! 10% off would help but even at that it is going to be hard to justify that expense no more than I sew. Sam[/QUOTE]

I bought my LS1 ZZ because my tax return check came in one hand and out the other. The cost of the Sailrite is offset by how much I've saved over paying someone else to make whatever. And you'll be surprised how many non-boat things you will sew. BBQ cover, jeans. When I shorten pants, I take the leg cut-off and sew one side to make a little bag. I'm about to make a case for the hatch boards, a sun awning for the side decks( I already made one fo0r the bow), carry bags for the 8 beach umbrellas, etc.
 

Sumner

.
Jan 31, 2009
5,254
Macgregor & Endeavour 26S and 37 Utah's Canyon Country
.... The cost of the Sailrite is offset by how much I've saved over paying someone else to make whatever. ....
Another factor that off-sets the price is the service. If you sew much regardless of the machine used there will be times that it finally needs adjustments or parts or both. Sailrite stocks all of the parts for the machine and has videos and other instructions that clearly show you how to service and maintain the machine.

I have a friend that bought a secondhand commercial machine and he has had to find someone who can service his machine. The other problem he has run into is that the machine sews very fast, which is a good point for someone who sews for a living but not so good for us who are learning and doing complicated projects.

With the Sailrite machine it is easy to control the speed and I made...


http://purplesagetradingpost.com/sumner/macgregor-canvas/canvas-14.html

... a simple foot-control box that even slows it down where you can stitch as slow as you want which is helpful when going around corners and other times.

I've never regretted for a moment spending the money necessary to buy one and Ruth and I have made a number of boat projects using it ....

http://purplesagetradingpost.com/sumner/macgregor-canvas/canvas-index.html

...... and yes I also repaired jeans and recently made a seat cover for one car and....



....... packs for my motorcycle.

I've also got their...



...hot knife with the foot and love it and the speed which you can cut fabric on any surface. I also ....



http://purplesagetradingpost.com/sumner/macgregor-canvas/canvas-21.html

... use a solder gun for some cuts but it is way slower to use than the hot knife for long cuts which I've had to do a lot,

Sumner
==========================================================
1300 miles to The Bahamas and Back in the Mac...
Endeavour 37 Mods...
MacGregor 26-S Mods...
Mac Trips to Utah, Idaho, Canada, Florida, Bahamas
 
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Mar 27, 2016
52
Corsair F-24 denver
I realize this is somewhat off the topic but I'm in the process of making a complete cockpit enclosure for our Albin 25 using this fabric. http://www.ebay.com/itm/18-oz-Vinyl...977829?hash=item35dd97c525:g:JccAAOSw7NNULpg6 It's not for everyone but it offers a number of advantages over Sunbrella and sewing. The fabric is waterproof. It's not woven like Sunbrella so doesn't need to be sealed on the edges. It is easy glued with HH-66 Vinyl Cement so doesn't require sewing. Vinyl windows can be glued directly to the fabric. It's much cheaper than Sunbrella. I've sewed for many years but don't own a Sailrite sewing machine although I do own a standard home sewing machine and an industrial sewing maching. I find gluing this material is faster and easier than sewing. It is definitely an option for those people doubtful of their sewing skills. I first started using this material about 30 years ago when I made a waterproof deck for our whitewater tripping canoe. I sewed the original one using this fabric but glued all subsequent versions once I realized how easy it is to glue. I still will do some sewing on the enclosure. For instance, my design requires a tensioning mechanism using fastex buckles and webbing. I sew the webbing to a triangle of the fabric then glue it to the enclosure. Also I will sew a strip of this fabric to either side of the zippers and then glue the zippers to the fabric. Sewing to small pieces of material is easier for the beginner than sewing something in to a large piece of fabric so only minimal sewing skills are required with this material. Not trying to talk anyone out of sewing their sailing projects but just pointing out there is a viable alternative out there. I've glued up many waterproof bags with this material using a roll down top and fastex buckle to secure the roll.
 
Nov 9, 2012
2,500
Oday 192 Lake Nockamixon
http://www.ebay.com/itm/18-oz-Vinyl...977829?hash=item35dd97c525:g:JccAAOSw7NNULpg6 It's not for everyone but it offers a number of advantages over Sunbrella and sewing. The fabric is waterproof. It's not woven like Sunbrella so doesn't need to be sealed on the edges.
The question is, how well the the vinyl hold up to UV? One of the reasons Sunbrella acrylic fabric, and similar fabric Weathermax 80, is used for sail covers, dodgers, biminis, etc. is because the fabric is very UV stable, and can be left outside all the time.

I don't have experience with vinyl material being in the sun all the time, so I'm asking.