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Making Holdfasts

2K views 13 replies 7 participants last post by  gmercer_48083 
#1 ·
I have a bench with 3/4" dog holes, and I presently use the cheap cast hold fasts. The cast hold fasts are not dependable...so I want to make new ones using rod steel. I am going to buy a weed burner type propane torch to heat the steel for bending. The question I have is about the diameter steel to use for the holdfasts. Is 5/8" diameter adequate, or should I use 3/4" diameter? My bench top is 2-3/4" thick oak. I have 5/8" rod already, but wonder if it will just flex and bend in use. Has anyone any experience?
 
#3 ·
What he said ^

I've bent a lot of metal by heating it with an Oxy Acetylene torch, not Propane. A weed heater will heat a large area and it might work, I dunno. As far as the diameter I think 5/8 will work with a gradual arc.
Here's some examples on You Tube;
https://www.youtube.com/results?search_query=make+hold+fasts
 
#6 ·
#5 ·
I used a propane 500,000 BTU weed burner just yesterday to burn
some old vines off of a chain link fence.
I was pretty disappointed that it didn't work to my expectations
as there was too much flame and not enough heat to do the job.
I would suggest you make a small forge with some bricks to contain
the heat - especially if you want to make more than one hold-down.
I agree that heating large steel with the weed burner will be fruitless.
try it and see - you will come to your own conclusions.
experiment with the 3/4 and 5/8" material to see what will work for you.
search YouTube for homemade propane forge examples.

.

.
 
#7 ·
Thanks Woodnthings,
I went to HF yesterday and the weed burners were out of stock. They said they will get a delivery wed, so I have to wait and see if they get one. If I find it does not get the steel hot enough... I will try surrounding the flame with some fire bricks. I am still unsure if using 5/8" rod in a 3/4" bench hole will work. I don't have an anvil, so I am planning on using a 2"x 3"x 4" solid bar as an anvil and a vise to form it.
 
#10 · (Edited)
Check this video out




He uses a simple single burner propane torch, two would have been quicker he says, but it worked. If they still sell MAPP gas, it burns hotter than Propane and fits the same torch head. As far as the hole size, he explains at 3:38 in, why it works:


 
#9 ·
Another in the camp that a weed burner probably won't output the heat needed to bend a 3/4" steel rod, with some blacksmithing experience to back that up. Those weed burners don't put out a ton of heat, they're only meant to scorch leaves after all, and a ton of heat is what you need to get a big honkin piece of metal like that to bend easy. A firebrick enclosure will help, but even then its a big maybe. Personally, short of building a forge burner which is amazingly easy to do, I'd find an oxy-propane torch. If memory serves Home Depot carries a small one for about the same price as a weed burner, and the much higher flame temps would help
 
#12 ·
I have bent many, many 1/2', 5/8" and 3/4" mild steel rods with a simple propane torch. I can't figure why some you think it can't be done. Maybe if you were making a hundred of them I might suggest more heat, but for a few? Go for it with what you have, assuming you have a common plumbers torch. Steel melts at 2750F; a common propane torch will do about 1970F. A yellow cylinder of MAPP will increase that to around2100F. Either gas will do for bending and forming. I would not consider a weed burner since the flame is too spread out and thus not really hot enough (more of an orange/ yellow flame).

It takes a little bit of time to get your rod to cherry red, but it still won't take any longer than five to seven minutes per bend. Have your radius form ready, chuck your rod in a vice (I mark my heat zone with soapstone), fire the torch up to max and keep the flame moving along and around your heat/ bend zone. The hottest part of a torch flame is at the point where dark blue meets light blue flame. All you need is a dull orange/red color, but make sure the color is in the entire heat zone before attempting a bend. Also keep the heat zone away from the vice jaws to minimize heat sinking.

Welding gloves come in handy unless you are bending long rods and can hold the very ends. When finished bending I toss my rods in a bucket of water or throw a soaking rag on the rod to quickly quench it.

Remember to overbend a slight bit as mild steel will open up a bit while cooling.

Easy peasy.
 
#14 ·
Update: I purchased the HF weed burner and assembled a make shift forge. The bricks used for the bottom and sides are 2-1/2 x 4 x 9 for the bottom and sides, and for the top and rear I used 1-1/4 x 4-1/2 x 9. The opening is 4-1/2 square and 9 long, and has a 1" opening at the rear. It was laid onto a baking tin and sets on my workmate. Using the weed burner, I found a sweet spot about 4" away from the opening. I never had to crank it up very high for it to easily heat the 5/8" rod to red hot...about 4 minutes.

I did find a problem with the torch though... after it cooled the 2" tube fell off the burner, so I will have to use set screws to reattach it (no big deal). Overall it was a success, and I would recommend trying it.
 

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