Heat Blanket Side Bending

[folms]

Has anybody had any experience with the plans for the heat blanket bending system that are sold in the classifieds here at the Mandolin Cafe? #Does anybody bend this way? #How much does one of these systems cost to build? Also what form can this system be used with?

[Keith Newell]

I have the plans and most the components for the bending, just havent had time to get it together. I know you can find some cheaper heat blankets on the net...ebay seems a bit expensive. I found a 2" X 18" silicon rubber heat blanket for about $30. I can post a link later when I get to work and can access that computer if you want. I just bent these this afternoon after spraying the hanging mando, fixing a dishwasher, installing a stove and drinkin 5 beers...how'd I do??
Keith Newell
http://www.newellmandolins.com

[Keith Newell]

f STYLE

[Keith Newell]

You can bend most any shape but the logistics of the F style means you need to have some machining or shop experience in my opinian. Fixturing will be alot harder then the A style. It doesnt really take that long to bend an A or F style mando, the only drawback is when you bend a specie like Western big leaf maple and pop the grain or do an almost clean break on the bending. Im not sure how much the heat blanket system will cure that. The best cure I've found is to #1 open a beer, #2 turn on the tape of the KBOO bluegrass show from last week you made and #3 take your time!
Keith Newell

[folms]

Yeah, I bought the plans too,I've also bought a stewmac bending iron,with which I'm not having a great amount of success with. I've managed to bend the long side with scroll with only one crack on the inside which I think I can glue and the easy one on the trebble side. The one over the top seems impossible, I've broken 6 or 7 in a two week period. I might also mention that this is my first mandolin and I picked the quilted maple to use for the wood which probably was a mistake, I should have picked something easier, like a banjo, but I love the mandolin,and thought I could show it a little more respect by building one than I ever could with my horrid playing. I might add that I've been a carpenter for 32 years (custom homes),so with tose kind of fingers you can understand why my wife makes me go to the basement. But anyway, the plans seem kinda vague, I checked out some part #s and it looks to me like it might cost a bit more than the authors estimate? Does it take a special form? I,ve just got the one built from Simonoff's new book, will I have to make another like yours? By the way is that a one piece form? And what material is it made of? Another Question I have about this system is, When you put it in the form do you leave the heat blanket on the sandwich, would'nt you have to make a larger form to make up for the thickness of the sandwich, and shim stock material,and the heating blanket? You'd end up with a slightly smaller mando, would'nt you? It seems to me it might be hard to get it all in the form. I don't know what I'm gonna do with these plans yet, or if I want to spend more money on this new addiction or just keep trying with the stew mac iron. Either way 5 beers ain't gonna do it, Im going to get the whole 12 pack, and than back to the shop, hey its saturday nite What the heck. Thanks for your input and super pics. folms

[Chris Baird]

I find when bending the tight curves with an iron it helps to: thin the stock down especially in the area where it will be glued to the block, secondly if it just won't make the bend with pressure you know will not cause a crack just let it cool down and "rest". When you come back to it 30 mins later it will magically go a little further with medium pressure. I just keep slowly working those tight curves around letting them "rest" and doing other stuff inbetween.

[folms]

Thanks Chris, I just managed to get the hard one bent, I took it down to .065 and it bent fairly well, not as perfect as i would have liked, but it might be acceptable with a little tweaking.
Also I'm having trouble finding the parts that are suggested in the plans for the blanket bending system in the classifieds, any help will be appreciated.

[timeoutlaw59]

Hey mandolinkgm what kind of material are your fixtures made of??

[mandomaniac]

The silicon heat blankets are available from various sources. The folks I recommended in the Parts List/Sources section of the Plans provide high quality blanket AND the thermocouple .....and with long enough leads....for what I feel is a great price. The thermocouple is necessary for the system to do its magic. Set temp at 305-310, follow the Method, and that long F section will bend smoothly and accurately. I use solid male/female forms...but I like Keith's outside mould. Either way, make the mould dimensions accordingly...ie., my solid male form's surface is .100 under the desired final outline. This accounts for the .010 slat,foil,paper, and the .075-.085 side. Closer than horseshoes.....and the system WILL allow this VERY accurate moulding of sides. If Methods are followed, there is virtually no springback either.
As to the cost: A mando sized blanket(4x36)& thermocouple (from rec. source), and all necessary components(if you are a smart eBay shopper) will run you $150 or LESS. Likely less! If you buy off the shelf from supplier....well dig deep! OK....the shimstock (order from MSC)will add some to that if you don't already use it.I have seen new components on eBay for a song....just luck of the draw. Recently bought some to make additional completed systems and did real well. All the components turn up on eBay. Be patient,watch, and price can be lower.
Hope this helps....Tom

[Keith Newell]

Timeoutlaw59, the fixures are 6061 aluminum. Some I have hard anodized and some are nickle plated.
Keith Newell
http://www.newellmandolins.com

[mandomaniac]

Some good news for purely mando builders....I worked out a deal with my blanket supplier to get cheaper price on mando sized blanket /thermocouple (2 x 30). I can do this ONLY if there is enough interest(volume is key) so please contact me. With this deal, the price of the system in my PLANS should run in neighborhood of $100.... #Hard to beat that! #Sometimes small IS better!!! # http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif # # #....Tom

[mandomaniac]

If you have purchased PLANS, but have not yet ordered blanket...contact me! I can save you some $$$. If you haven't purchased PLANS (or a completed system!) .....what's the hold up?
Quit crying over bad sides!!! #http://www.mandolincafe.net/iB_html/non-cgi/emoticons/tounge.gif # Tom

[Keith Newell]

Here is a supplier if you have almost any size to bend of just the silicon rubber heater blankets.
http://www.omega.com/pptst/SRMU_HEATER.html
Keith

[mandomaniac]

Hey Keith, I checked out the link. Thanks. If I read the info correctly, these are blanket ONLY. They do not include thermocouple!! This is VERY important for the system to work to control temp exactly! What prices they show...they look a hair cheaper....$31 and change for 2x30....but they simply won't do the job for this system. For about $15 more you can control the temp to exact degrees! No contest IMHO. And don't get fooled by the 'thermostat' they offer. Nowhere near the ability to control temp, and big jump in cost. Hope this helps......Tom

[mandomaniac]

Hey Again...
Well the digital world is now mine! Just need to learn how to use this high tech bugger. I took some pics of my newest prototype...ArchJazz mando.....and thought I'd post a pic of the cutaway here. Sides were bent with my Bending System. So take a look at those tight curves! I use solid forms ....cheap and easy. BTW here is a pic of F5 scroll done with system. I'm about to bend sides for another prototype, so I will try to take some shots of the process and share as well. Need to pass Photography 101 first!
http://img23.photobucket.com/albums/v69/mandomaniac/pickguardVT.jpg
http://img23.photobucket.com/albums/v69/mandomaniac/bestneck.jpg

[folms]

Just a real beauty, Tom, Maybe someday I'll be talented enough to build one that nice, I can dream can't I ? Talk Later.