1T Arbor Press - simple punch and stitching chisel mod

[Ingenero]

Hello all!  I'm new here, but have been reading posts for a while and learning a lot, and decided to share a project I'd finished that might help others.

I've seen a few posts on modifying a 1T Harbor Freight Arbor Press to accept punches or stitching chisels, but those involved using a lathe or having someone with access to one machine a slot in to the arbor ram/rack and drill and tap a hole for a set screw.  I managed this entirely with a drill press and a tap, which may be more accessible for people.  This should work with any inexpensive 1T drill press - the design is pretty universal.

A couple of caveats.  I already had the drill press and a really good set of metal drill bits - that made this doable without being super pricy.  If you have general drill bits (the "wood and metal" types), I'd suggest getting a metal specific bit as drilling even mild steel will tear them up pretty quickly.  If you're not going to be doing this often, an inexpensive bit should be fine.  Finally, unless you have a tap for steel already, you'll need to buy one.  Be careful to ensure it's intended for steel - an inexpensive Harbor Freight set will have the caveat that it's intended for use on plastic and soft metals (like copper) but not steel, so be careful.  
 

What I used:

Drill Press - DO NOT try this with a hand drill, you won't be able to drill the hole straight enough and are liable to break your bit.

1/2 inch (12-13 mm) drill bit intended for drilling mild steel

Drilling/cutting/tapping Oil - I used Kroil, but most lubricating oils work well.

Tap and corresponding drill bit (I used a 10-24 tap and 5/32 inch metal drill bit - make sure it corresponds to a machine screw you can buy in the proper length)

machine screw with the threading corresponding to the tap (I used a half-inch screw, I'd suggest one that's 1/2 to 3/4 the length of one of the short sides of the ram)

Tap Wrench

Some details about the Harbor Freight Arbor Press ram/rack (in case someone needs more dimensions - I couldn't find this online)

Dimensions: 9 3/8 x1x1inch

1.5 inches at top and at bottom untoothed

20 teeth, 0.25 inches tall, 3/8 inch spacing

 

Procedure:

I started by chucking the 1/2 inch drill bit in the drill press and positioning the ram on its end (tallest dimension vertical) under the 1/2 inch drill bit with the bit slightly off-center of the ram (see the image of the ram end below).  This made the process of drilling and tapping the set screw hole easier.  Ensure the top of the ram is 90 degrees to the drill bit (a carpenter square works well, so does anything that's definitely square) -  that ensures your hole isn't skewed and your tool will be reasonable straight, plus you won't accidentally drill out the side of the rack.  I would highly suggest clamping the ram in place - it makes the drilling process much easier.  
 

Next, put some cutting oil on the drill bit - it'll help ensure a cleaner hole, keep the operation cooler, and make things easier to clean up.

Now drill - slowly.  You should drill in to the metal a few mm, pull back, and drill in again, repeating until you have a hole about an inch deep.  Stop for a minute when the arbor ram's metal begins to feel warm, add a few drops of cutting oil on the bit, and drill further.  Again, don't push it and try to get this done, that's a good way to break a bit or hurt yourself.

Once the hole is deep enough (around an inch to an inch and a half, or 25 to 40 mm), unclamp the ram and lay it on its side (longest dimension horizontal) with a side other than the one with the rack teeth vertical.  That will make the set screw accessible.  Now unchuck the old, larger drill bit and chuck in the smaller drill bit corresponding to the tap.  Add cutting oil and slowly drill until the bit breaks through in to the original, larger drill hole.  Ensure the hole is clean (run the bit up and down a bit), then unclamp the ram and clean up the metal chips on it.

Next, put the tap into the tap wrench, add a couple of drips of cutting oil, and slowly tap the hole.  Once you're through in to the main hole, unscrew the tap, and clean everything up.  Ensure no metal chips or excess oil remain on the ram to drop on to your leatherwork.  Take your set screw (machine screw) and ensure it properly runs in and out of the set screw hole - and check that it properly holds your tools.  Put your ram back in the press (you'll need to remove the set screw first), and use your new tool!  Now I can work on things without my wife yelling at me at night.

[Ingenero]

If anyone stumbles across this in the future (I hope you have flying cars!), it not only works well, but has made it a lot easier, and far quieter, to get my stitch holes marked and ready for use.  Just make sure to use the right surface underneath the ram (I use a cutting board with some scrap leather on top), and think about how to keep the arbor steady if you're not going to bolt it down (I'd recommend weights).

What it has done is let me make progress while my kiddos are sleeping!  I definitely can't complain about that.

[RabbyTat]

I did something similar, but used a 3/8s hole on one end. This allows me to use sections of plastic plumbing tubing (like from your kitchen faucet sprayer) on several stamping tools for a friction fit. Many tools fit right inside this tubing and they are snug, but can be twisted as desired. I have been stamping with such a set-up. I am also looking to do snaps, rivets and grommets.

I might go with your half inch hole on the other side for other uses. (Anyone know of a good source for good simple letters which might work in such a press?)

I have also used a cutting board under the ram, but made a plywood platform with a metal bolster. Am rigging an alignment guide to keep long repetitive runs lined up for stamping tasks. Sort of like a table saw fence.

 

[Ingenero]

On 10/16/2024 at 2:54 PM, RabbyTat said:

I did something similar, but used a 3/8s hole on one end. This allows me to use sections of plastic plumbing tubing (like from your kitchen faucet sprayer) on several stamping tools for a friction fit. Many tools fit right inside this tubing and they are snug, but can be twisted as desired. I have been stamping with such a set-up. I am also looking to do snaps, rivets and grommets.

I might go with your half inch hole on the other side for other uses. (Anyone know of a good source for good simple letters which might work in such a press?)

I have also used a cutting board under the ram, but made a plywood platform with a metal bolster. Am rigging an alignment guide to keep long repetitive runs lined up for stamping tasks. Sort of like a table saw fence.

 

That's a good idea!  I was thinking some type of tubing might help, hadn't thought of 3/8 tubing.

 

And I've purchased similar letters on AliExpress - probably have what you're looking for, I've purchased some solid letter stamps from them.  Not fancy, but work great and don't cost an arm and a leg.

[RabbyTat]

On 10/27/2024 at 12:58 AM, Ingenero said:

That's a good idea!  I was thinking some type of tubing might help, hadn't thought of 3/8 tubing.

 

And I've purchased similar letters on AliExpress - probably have what you're looking for, I've purchased some solid letter stamps from them.  Not fancy, but work great and don't cost an arm and a leg.

I also drilled and tapped a hole from the side of the ram to insert a small bolt to hold other tools which are of 3/8s diameter. Have not needed it yet, but it is there.