Well I bought one! HMD904. Found one on ebay that looked to be in very good condition and included a few annular cutters for $500. I will try it out and see how it works for me. If I don't like it I am sure I can sell it and get my money back.
School me on magnetic drills
- Thread starter bdog
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npalen
Elite Member
I've spent a few hours back in the day running mag base drills building special machine tools. (bomb making machines back in the Vietnam era) My only complaints are that the cutting speed is usually very slow when using small bits for starter or pilot holes and, yes, they can get heavy after a while. The reason we always used starter drills was to get a good location on the center punched hole and pilot drills can drastically reduce the downforce required on the next larger twist drill bit. Reducing downforce translates into better chance of the magnet holding. Another trick is to thin the web on the larger diameter drill bits to reduce downforce required. On the flip side, the slower RPM is a good thing for the larger holes and especially large diameter annular bits. Annular bits were not used as much back in the day but they certainly have advantages. It's heartbreaking however to see one shatter. They have to be resharpened by an experience tool grinder due to several facets that make up each cutting tooth.
I'm finding the cheap step drills to be very useful even in a drillpress. The advantage when using them in hand drills is much less pressure required when drilling larger hole in thin metal. $10 can buy a cheap set of three if you shop around.
step drill - Yahoo Image Search Results
I'm finding the cheap step drills to be very useful even in a drillpress. The advantage when using them in hand drills is much less pressure required when drilling larger hole in thin metal. $10 can buy a cheap set of three if you shop around.
step drill - Yahoo Image Search Results
I bought a Champion RotoBrute AC35 from Amazon in December. The manual warns about weak holding below 1/2 in, etc.. There are cheap annular cutters on line. I saw some threads where guys have made small "drill press" forms in which to securely mount the magnetic drill. Mine came with a safety chain. Some guys have used a 1/2" or thicker plate that clamps or screws or bolts in place. The slightly larger Champion RotoBrutes have a variable speed and reverse so you can use their bit sets wherein on single bit predrills, cuts threads and backs back out of the hole, all in one function. The cheaper AC35 that I bought is just as heavy duty, but no reverse and runs only at about 700 rpm. For me it's a great alternative to the drill press. I'm planning on making a small drill press mount for it thought, to be able to use the chuck for smaller diameter drill bits.
The chuck attachments available are great, but almost touch the base level on a flat surface. That's why some ppl have used heavy plate to make a "stand off" mount so it can be used with the standard chuck for smaller diameter holes.
The standard 3/4" Weldon shank annular drill bits only go down to 1/2" and most kits bottom out at 9/16 ". I got mine to drill the holes in base mounting plates PRIOR to cutting them and welding them in place. Also, working on large farm equipment, it's nice (if there's room) to place precision holes. The AC 35 does well in making frame hitches, etc..
The chuck attachments available are great, but almost touch the base level on a flat surface. That's why some ppl have used heavy plate to make a "stand off" mount so it can be used with the standard chuck for smaller diameter holes.
The standard 3/4" Weldon shank annular drill bits only go down to 1/2" and most kits bottom out at 9/16 ". I got mine to drill the holes in base mounting plates PRIOR to cutting them and welding them in place. Also, working on large farm equipment, it's nice (if there's room) to place precision holes. The AC 35 does well in making frame hitches, etc..
jwmorris
Veteran Member
- Joined
- Oct 3, 2007
- Messages
- 1,084
My mag drill is very heavy, it is great for parts that won't fit in a drill press or mill but I don't use it unless I have to.
Thanks for the info. I saw the cheap annular cutters on ebay. I was scared of them because they had no brand name whatsoever and I could not find any reviews. I opted for this set from Hougen for $187 Hougen 12,000 Series 2" Annular Cutter Kit 12002 - Ohio Power Tool
It includes cutters from 5/8 to 1 1/8 and I bought a 1/2" separately as well as the chuck attachment. This should cover my needs for a long time.
I like the idea of the drill press form. I think I will build one.
It includes cutters from 5/8 to 1 1/8 and I bought a 1/2" separately as well as the chuck attachment. This should cover my needs for a long time.
I like the idea of the drill press form. I think I will build one.
re: the Hougen 12,00 series 2 Annular cutting kit... I bought two cheaper sets, only 1" not the 2". The first cost about $140, but had to pay for shipping. All the bits had porosity. The first set had actual HOLES in the gullet of two bits, over 1mm diameter! They wouldn't replace individual bits so sent that kit back and lost about almost $40 on return shipping. Then bought a more expensive 1" Chinese set ( $170) which arrived full of porosity and only one center pin, but at least no holes in the gullets. So I am out about $60 on top of the $170 and I still have low quality bits...
Shoulda' gone with the Hougen at the outset.
Shoulda' gone with the Hougen at the outset.
