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| Author: | Robert Renick [ Wed Feb 24, 2010 10:07 am ] |
| Post subject: | Bending slats question |
Broke my first sides last night, and not sure what is up with my bending slat. I am using a Everett style jig with a blanket from Bluescreek, but the slat is from LMI. I see they only offer this one slat, which is why I thought it would be correct for the procedure. This is 24 gauge stainless. After the first bend it is bent at the waist and curved at the bouts. It became clear that I need a slat under the wood to prevent the cracking, but now this slat will not provide support as a bottom slat since it is bent. In John's and other videos I have watched the slats are all straight and clearly have been used more then once. So after some time in the archives, I have seen the terms, stainless, spring stainless and spring steel, but still don't know which is used for what, and what do I do with the bent slat, will work for a top slat, but can I bend it flat, am I supposed to flatten it after each bend? I would also like to source the correct product on the west coast, thanks to Bluescreek for great prices and service, but I would like to avoid another $20 in shipping and 10 days in transit if I can. Thanks, Rob |
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| Author: | TonyKarol [ Wed Feb 24, 2010 10:16 am ] |
| Post subject: | Re: Bending slats question |
Stainless, no spring is OK, it workls, but as you have found out, it takes the bend and doesnt return flat .. you need thin spring steel .. mine is 10 thou (actually called shim stock), and you need an upper and lower slat ... Unless you have a steel place near you where they sell the stuff, you are ordering ... |
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| Author: | Mark Groza [ Wed Feb 24, 2010 10:54 am ] |
| Post subject: | Re: Bending slats question |
I use 12 thousand stainless without any problems.I do have spring steel as well, but have had too many problems with it's reaction to the acids in the woods (staining) , so i only use those on top of my blanket now. The spring steel slats are also prone to rust,  which isn't very good either.
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| Author: | Robert Renick [ Wed Feb 24, 2010 11:22 am ] |
| Post subject: | Re: Bending slats question |
Mark Groza wrote: I use 12 thousand stainless without any problems.. I looked at an online gauge chart, .012 is 30 gauge, 24 gauge is .022. Not sure how this will effect the metal taking a set, I can see how a bent sheet can still be used on top of a stack, but how can the bent metal offer support on the bottom, which is where my cracks occurred? Rob |
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| Author: | WaddyThomson [ Wed Feb 24, 2010 11:27 am ] |
| Post subject: | Re: Bending slats question |
Check with John. He uses a Stainless alloy that seem to be more resilient than regular stainless. It does bend some, but you can straighten it out by hand. |
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| Author: | evanmelstad [ Wed Feb 24, 2010 11:34 am ] |
| Post subject: | Re: Bending slats question |
I just switched from bending on a pipe to blanket/form. I tried one set of sapele with aluminum flashing for slats and ended up breaking a side on the inside of the waist bend. Tried a sister set with spring steel and had no problems. Sorry I can't help with west coast sourcing, but the support of the spring steel on the inside of the waist bend was clearly the difference between success and failure on this particular set. I haven't tried stainless, but you could always rig it up so that the stainless slat is pulled up tight against the side with an aluminum bar and springs if you are worried about supporting the waist bend. |
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| Author: | Tim L [ Wed Feb 24, 2010 11:51 am ] |
| Post subject: | Re: Bending slats question |
I uses both .010 and .015 spring steel that I bought in rolls that are 6" x 10' long. Can be bought through either MSC or McMaster Carr. They can be reused and I have had no rusting issues. My experience is that spring steel is not that commonly used. Finding it locally would be a challenge especially in an area known for lumber mills. I used stainless slats originally but switched to spring steel due to cracking problems also. The stainless can be straightened easily, and it was thicker, but it seemed to me that the spring steel gives better support. Just my .02 Tim |
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| Author: | Robert Renick [ Wed Feb 24, 2010 12:03 pm ] |
| Post subject: | Re: Bending slats question |
Tim L wrote: Just my .02 Tim, Is that your 2 cents or your 20 thousandths. Either way, thanks. I have a sheet metal buddy in town, and we do get deliveries here from the big city twice a week, but I want to be sure that I am asking for the right stuff. Any preference between the .010 and the .015? Rob |
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| Author: | Mark Groza [ Wed Feb 24, 2010 12:34 pm ] |
| Post subject: | Re: Bending slats question |
comfyfoot wrote: Tim L wrote: Just my .02 Tim, Is that your 2 cents or your 20 thousandths. Either way, thanks. I have a sheet metal buddy in town, and we do get deliveries here from the big city twice a week, but I want to be sure that I am asking for the right stuff. Any preference between the .010 and the .015? Rob My preferance is .012"x6".I've had no problems useing it and it bends back with little effort. |
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| Author: | Pat Hawley [ Wed Feb 24, 2010 12:40 pm ] |
| Post subject: | Re: Bending slats question |
My own personal feeling is that there is value to going with spring steel to get the support under the side during the bend. Especially if you are doing a cutaway. If you look at Taylor's Factory Friday's videos you will see that the side bending machines they created were designed to do just that. Also, I haven't cracked a side since getting the spring steel slats from Blues Creek. They do rust though so I use aluminum foil as a barrier between the slats and the wood along with some dampend kraft paper to provide some moisture. The other challenge to the spring steel slats is, uless you come up with a way of holding the bottom slat in place (which I haven't) you can't use them to bend bindings because they will straighten and break the bindings while you are trying to get them off the form. Pat |
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| Author: | bluescreek [ Wed Feb 24, 2010 12:47 pm ] |
| Post subject: | Re: Bending slats question |
Stainless steel is more involved. There are different alloys and hardness. I use a 302 alloy that is harder than the shim stock you see at MSC . This will take a slight bend but can be flexed out. The key to the slats is support and heat transfer. Sprint steel is a hardened steel and can cause staining issues . It is also high in iron and will rust. I personally use stainless . It works well for me . |
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| Author: | Michael Dale Payne [ Wed Feb 24, 2010 2:32 pm ] |
| Post subject: | Re: Bending slats question |
I will mention here for the benefit of those that may not know. the typical Fox style bender plans and pre-manufactured benders have a spring loaded aluminum bar that goes under the sandwich at the center of the waist. I know many that do not use this bar. I really want to recommend that you do use it. Even if you use a slat below the wood; as the waist bend is pulled down the slats are being pulled into an ever tightening radius. The lower slat wants to pull away from the wood at the apex of the bend if not drawn tight to the wood by some means. This spring loaded bar keeps the sandwich pulled tight to the wood during the waist bend. it is in my opinion essential to helping preventing cracking and faceting in the waist bend. |
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| Author: | Daniel Minard [ Wed Feb 24, 2010 3:54 pm ] |
| Post subject: | Re: Bending slats question |
Rob; You definitely need a slat on both sides of your wood. Pat; I use spring steel & have yet to break a binding... I HAVE ruined a few sides though. You can drill a 1/4" hole in each end of the lower slat & tie a piece of cord to it. Put a cleat on the ends of your bender so you can tie the slat down on both ends, once you have finished sliding the cauls into their final position. The waist will spring up as you raise the waist caul, but as long as you free the bindings as you raise the caul, you shouldn't have any problems. I use spring steel too, & think the extra support helps to prevent cracking. Pity about the rust though... Just don't be tempted (as I was) to paint your slats with high heat paint... I doesn't stand up to heat or wear as well as I hoped. The slats are still rusty, but now they have goopy black paint on them too! Gotta strip the paint off before I use 'em again. Micheal; Thanks for the comment about the cross bar. lately, I have been using mine simply to hold the form in place. I'm going to hook up the springs again & use a couple of pins to hold the form from slipping. |
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| Author: | Robert Renick [ Wed Feb 24, 2010 6:21 pm ] |
| Post subject: | Re: Bending slats question |
Thanks all, I am beginning to get it. Michael, I did not know that about the Fox bender, I am using an Everett jig I made just from the pictures. I am bending the Gibson L-O from the GAL plans, it has a pretty tight waist, I think that the spring steel may help with this. I may jump to the other form that I made which is the Antes parlor, looks easier to bend for a first timer. That is an interesting feature of the Fox bender, I may want to work on that upgrade sooner then later. Rob |
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